Anaesthesia for hip fracture surgery in adults

  • Review
  • Intervention

Authors


Abstract

Background

The majority of hip fracture patients are treated surgically, requiring anaesthesia.

Objectives

To compare different types of anaesthesia for surgical repair of hip fractures (proximal femoral fractures) in adults.

Search strategy

We searched the Cochrane Musculoskeletal Injuries Group specialised register (December 2000), MEDLINE (1996 to December Week 4 2000) and reference lists of relevant articles.

Selection criteria

Randomised and quasi-randomised trials comparing different methods of anaesthesia for hip fracture surgery in skeletally mature persons. The primary focus of this review was the comparison of regional (spinal or epidural) anaesthesia versus general anaesthesia; this has been expanded to include other comparisons. The use of nerve blocks pre-operatively or in conjunction with general anaesthesia is evaluated in another review. The primary outcome was mortality.

Data collection and analysis

Two reviewers independently assessed trial quality, using a nine item scale, and extracted data. Results were pooled wherever appropriate and possible.

Main results

Seventeen trials, involving 2305 patients, comparing regional anaesthesia with general anaesthesia were included. All trials had methodological flaws. Pooled results from eight trials showed regional anaesthesia to be associated with a decreased mortality at one month (53/781(6.8%) versus 78/826(9.4%)); this was of borderline statistical significance (relative risk (RR) 0.72, 95% confidence interval (CI) 0.51 to 1.00). The results from six trials for three month mortality were not statistically significant, although the confidence interval does not exclude the possibility of a clinically relevant reduction (86/726 (11.8%) versus 98/765 (12.8%), RR 0.92, 95% CI 0.71 to 1.21). The reduced numbers of patients at one year, coming exclusively from two studies, preclude any useful conclusions for long term mortality (80/354 (22.6%) versus 78/372 (21.0%), RR 1.07, 95% CI 0.82 to 1.41).

Regional anaesthesia was associated with a tendency to a longer operation (weighted mean difference 4.8 minutes, 95% CI 1.1 to 8.6 minutes), and a reduced risk of deep venous thrombosis (39/129 (30%) versus 61/130 (47%); RR 0.64, 95% CI 0.48 to 0.86), although this conclusion is insecure due to possible selection bias in the subgroups in whom this outcome was measured. No other statistically significant differences in outcome were identified.

There was insufficient evidence to draw any conclusions from a further four included trials, involving a total of 179 patients, which compared other methods of anaesthesia (a 'light' general with spinal anaesthesia; intravenous ketamine; nerve blocks).

Reviewers' conclusions

Regional anaesthesia and general anaesthesia appear to produce comparable results for most of the outcomes studied. Regional anaesthesia may reduce short-term mortality but no conclusions can be drawn for longer term mortality.

Plain language summary

Synopsis

Regional anaesthesia may reduce the number of early deaths after hip fracture surgery but more evidence is needed to establish if it is better than general anaesthesia

The majority of people with hip fracture are treated surgically. Anaesthesia is used to prevent pain during the operation. There are a number of different types of anaesthesia and the most common are 'general' and 'spinal'. General anaesthesia, which usually involves a loss of consciousness, typically includes inhalation of gases. Spinal (regional) anaesthesia involves an injection into the space around the spinal cord, to prevent pain in the involved limb. Although there were fewer early deaths (within one month) in people given spinal anaesthesia, there was not enough clear evidence to tell if regional anaesthesia was superior to general anaesthesia. The effectiveness of other methods of anaesthesia could not be determined.

Background

The scope of this review, originally published in Issue 4, 1999, has been expanded in this update, published in Issue 4, 2001, to cover other methods of anaesthesia. However, the main focus remains the comparison of regional versus general anaesthesia.

The term proximal femoral fracture, or 'hip fracture', refers to a fracture of the femur in the area of bone immediately distal to the articular cartilage of the hip, to a level of about five centimetres below the lower border of the lesser trochanter. The majority of these fractures occur in an elderly population with an average age of around 80 years. Females predominate over males by about four to one (Parker 1993) and the injury is usually the result of a simple fall. Whilst the hip fracture is usually the only injury, the patients frequently have many other medical problems associated with aging.

An estimated 1.7 million hip fractures occurred worldwide in the year 1990 (WHO study group 1994). The number of hip fracture patients continues to rise, due to a combination of an increasingly elderly population and an increase in the age specific incidence. A prediction for global numbers of 6.26 million hip fractures by the year 2050 has been made (Melton 1993). The majority of these fractures are treated surgically; thus hip fracture surgery represents one of the most common emergency orthopaedic procedures. Surgical treatment may be either fixation of the fracture or replacement of the femoral head with an arthroplasty. Internal fixation involves using screws or pins, either alone or in combination with a side plate applied to the femur, or by the use of an intramedullary nail with a cross screw inserted into the femoral head. Arthroplasty involves excision of the fractured area of bone and replacement with a partial or total hip replacement, which may be cemented in place.

General anaesthesia refers to the use of a variety of intravenous and or inhalation drugs to render the patient unconscious. The patient may breathe spontaneously or require mechanical ventilation following the administration of neuromuscular blocking agents. Potential complications of general anaesthesia include adverse reactions to the drugs used, difficulty in maintaining or establishing an airway, intra-operative hypotension, aspiration of gastric contents, post-operative nausea, respiratory depression and damage to the teeth or upper airways.

Regional (also termed spinal) anaesthesia for hip fracture surgery refers to the injection of a local anaesthetic into the epidural or subarachnoid space at the lumbar spine. In some cases the patient also receives sedatives whilst the block is inserted and possibly during the surgery itself. The main complication of a regional technique is intra-operative hypotension, which may lead to cerebrovascular or myocardial ischaemia or infarction. Other problems may be an inadequate regional block, the rare complications of damage to local structures and headache secondary to leakage of cerebrospinal fluid from the dural puncture site. Specific advantages of regional anaesthesia may be a reduction in the incidence of thrombotic episodes and a reduced operative blood loss. These may be a consequence of an increased peripheral limb blood flow in combination with reduced venous tone. Alternatively they may arise from an alteration of blood viscosity and coagulability, as a result of changes in the metabolic and neurohumoral responses to surgery (Modig 1983).

Other forms of anaesthesia used for hip fracture surgery are the insertion of local nerve blocks around the hip. These may be supplemented with sedatives, analgesics or other parental drugs. A lumber plexus block refers to injection of a local anaesthetic agent into the area of the lumbar plexus close to the transverse process of the forth lumbar vertebrae (Winnie 1974). Only the plexus on the side of the fracture needs to be blocked, which may reduce the incidence of complications such as operative hypotension. A sacral plexus block refers to the injection of a local anaesthetic agent in the area around the sacral nerves (Mansour 1993). The use of nerve blocks pre-operatively or in conjunction with general anaesthesia is considered in another Cochrane review (Parker 2001).

An alternative type of anaesthetic involves the use of intravenous ketamine on its own. Ketamine renders the patient unconscious, thereby acting as a general anaesthetic, and has analgesic effects.

No consensus exists as to which is the best method of anaesthesia. Currently the choice of anaesthesia used for hip fracture surgery is determined by the personal preference of the anaesthetist concerned, following assessment of the patient's medical state. A general review of anaesthesia for hip fracture surgery (Covert 1989) summarised the possible advantages of different anaesthetic methods using information from eight of the randomised trials on this subject. In a meta-analysis, using Bayesian methods, of 11 randomised trials of regional versus general anaesthesia for surgical repair of hip fractures, Sorensen 1992 concluded that the superiority of one method over the other was unproven. Not all currently available randomised trials were included and, moreover, some trial data from two studies were duplicated in the analysis. A more recent meta-analysis of randomised trials for all types of surgery has demonstrated a reduction of early post-operative mortality and morbidity with epidural or spinal anaesthesia (Rodgers 2000).

Objectives

To determine the optimum anaesthetic technique for hip fracture surgery. Different types of anaesthesia, namely regional (either spinal or epidural), inhalation general anaesthesia, local nerve blocks and intravenous ketamine anaesthesia were compared. Variations in anaesthetic drug dosage and delivery or supplementary regional blocks were not considered within this review.

The following null hypotheses were tested within the trials included so far in this review:

1. There is no difference in outcome between regional anaesthesia (spinal or epidural) and general anaesthesia.

2. There is no difference in outcome between regional anaesthesia (spinal or epidural) supplemented with a 'light' general anaesthetic and general anaesthesia alone.

3. There is no difference in outcome between regional anaesthesia (spinal or epidural) and regional nerve blocks alone.

4. There is no difference in outcome between anaesthesia using ketamine (with or without a benzodiazepine) and inhalation general anaesthesia.

Criteria for considering studies for this review

Types of studies

All randomised controlled trials comparing different methods of anaesthesia were included. Quasi-randomised trials (for example, alternation), and trials in which the treatment allocation was inadequately concealed, were considered for inclusion.

Types of participants

Skeletally mature patients undergoing hip fracture surgery.

Types of intervention

1. Regional anaesthesia (if necessary supplemented by sedatives) achieved by injection of local anaesthetic into the epidural or subarachnoid spaces. This type of anaesthesia is also referred to as 'spinal' or 'epidural'.

2. General anaesthesia using intravenous or inhalation agents to render the patient unconscious. Unless otherwise stated, general anaesthesia refers to general anaesthesia using inhalation agents in this review.

3. Intravenous ketamine.

4. Local nerve blocks (if necessary supplemented by sedatives) when used as the primary method of anaesthesia.

Trials testing other methods of anaesthesia as the primary method of anaesthesia were considered for inclusion. Trials comparing the use of local nerve blocks in conjunction with general anaesthesia and the use of nerve blocks pre-operatively, are evaluated in another Cochrane review (Parker 2001). Also not considered in this review were trials comparing different types of drugs or techniques of individual methods of anaesthesia.

Types of outcome measures

The primary outcome measure was mortality (at 1 month, 3 months, 6 months and 1 year). In addition, data were sought from each study for outcomes in the following categories.

a) Peri-operative outcomes:
- length of operation (in minutes)
- hypotension (intra-operative or immediately post-operative)
- operative blood loss (in millilitres)
- transfusion requirements/fall in haemoglobin
- need for supplementary drugs to complete anaesthetic (new in second update)
- changes in body temperature
- pre and post-operative arterial blood gases
- changes in catecholamines and other stress response chemicals during and after surgery
- intra-operative cardiac arrhythmias
- time to mobilisation
- length of hospital stay (in days)

b) Complications specific to the method of treatment:
- aspiration pneumonia
- post-dural puncture headache
- damage to the upper airways or mouth from general anaesthesia
- secondary intervention required for anaesthetic complications
- any other adverse effects as detailed in each study (new in second update)

c) General post-operative complications:
(unless otherwise specified, the definition for these complications will be as detailed in each study, or by post-mortem)
- pneumonia
- myocardial infarction
- cerebrovascular accident
- congestive cardiac failure
- renal failure
- cardiac arrhythmias
- acute confusional state
- urine retention (requiring catheterisation)
- post-operative nausea and /or vomiting
- deep vein thrombosis (diagnosis confirmed by post-mortem, venography, isotope scanning, ultrasound or phlethysmography, whether this was performed routinely or only as clinically indicated)
- pulmonary embolism (diagnosed by isotope scanning, angiography or post-mortem)

d) Final outcome measures:
- mortality (primary outcome)
- change in mental function
- functional status
- return of patient to their pre-fracture place of residence

Search strategy for identification of studies

See: Unavailable search strategy

We searched the Cochrane Musculoskeletal Injuries Group specialised register (December 2000), MEDLINE (1996 to December Week 4 2000) and reference lists of relevant articles. In MEDLINE (OVID WEB) the following search strategy was combined with the first two levels of the optimal trial search strategy (Clarke 2000).

1. exp Hip Fractures/
2.((hip$ or femur$ or femoral$ or trochant$ or pertrochant$ or intertrochant$ or subtrochant$ or intracapsular$ or extracapsular$) adj4 fracture$).tw.
3. or/1-3
4. exp Anesthesia/
5. ((an?esthet$ or an?esthesia) adj4 (regional$ or local$ or general or spinal or epidural)).tw.
6. or/4-5
7. and/3,6

Articles of all languages were considered and translated if necessary.

Methods of the review

Data for the outcome measures listed above were independently extracted by two reviewers, and checked by at least one of the other two reviewers. In addition each trial was assessed without masking for its quality of methodology. Any differences were resolved by discussion between the reviewers.

The main assessment was by the quality of concealment of allocation which was scored either A, B or C according to the criteria in the Cochrane Reviewers' Handbook (Clarke 2000), or 3, 2, 1 or 0 as described below (item 1). A further eight aspects of methodology were used, giving a maximum score for each study of 11.

1. Trials with clear concealment of allocation (e.g. numbered sealed opaque envelopes drawn consecutively) were coded as A and scored 3. Those in which there was a possible chance of disclosure of assignment were coded as B and scored 2. Those in which allocation concealment was not stated, or unclear, were coded as B and scored 1. Those where allocation concealment was clearly not concealed, such as trials using quasi-randomisation (e.g. even or odd date of birth), were coded as C and scored 0.

2. Were the inclusion and exclusion criteria clearly defined? Score 1 if text states type of patients included and those excluded; otherwise score 0.

3. Were the outcomes of patients who withdrew or were excluded after allocation described and included in an intention to treat analysis? This particularly applies to patients allocated to regional anaesthesia where it was not achieved due to technical difficulties. Score 1 if these patients were either detailed separately or included in the analysis group to which they were allocated, or if text states that no withdrawals occurred; otherwise score 0.

4. Were the treatment and control groups adequately described at entry? Score 1 if a minimum of four admission details were given (e.g. age, sex, mobility, fracture type, function score, ASA grade, mental test score); otherwise score 0.

5. Were the care programmes other than trial options identical? Score 1 if text states they were; otherwise score 0.

6. Were the outcome measures clearly defined in the text? Score 1 if yes; otherwise score 0.

7. Were the outcome assessors blind to treatment group? Score 1 if yes; otherwise score 0.

8. Was the timing of outcome measures appropriate? This was considered to be a minimum of three months follow-up for all surviving patients. Score 1 if yes; otherwise score 0.

9. Was loss to follow-up reported and if so were less than five per cent of patients lost to follow-up? Score 1 if yes; otherwise score 0.

Heterogeneity between comparable trials was tested using a standard chi-squared test. In accordance with the revised statistical policy of the Cochrane Musculoskeletal Injuries Group, announced in March 2000, relative risks and 95 per cent confidence limits have been calculated instead of Peto odds ratios and 95 per cent confidence limits for dichotomous outcomes. Mean differences and 95 per cent confidence limits have been calculated for continuous outcomes. Results of comparable groups of trials were pooled using fixed and random effects models and 95 per cent confidence limits. Both Peto odds ratio and relative risk plots were viewed and a note was taken of where there was statistically significant heterogeneity (P< 0.1) using either method. The results for the random effects model are presented when there is significant heterogeneity in the results of individual trials. Any tests of interaction, calculated to determine if the results for subgroups were significantly different, are based on odds ratio results.

Description of studies

Three new studies (de Visme 2000; Eyrolle 1998; Ungemach 1993) were included in this second update. In the first update, the study of Juelsgaard 1998 was included.

In all, 37 studies were identified of which 21 trials were included in this review, 15 were excluded and one remains in Studies Awaiting Assessment. Of the 15 excluded studies, two were not randomised trials; eight involved comparisons outside the scope of this review; two (Tonczar 1981; Wickstrom 1982) involved neuroleptic general anaesthesia which was considered to be no longer appropriate for hip fracture surgery; one (Darling 1994) only reported one outcome, the rate of clearance of injected indocyanine green, which was considered not to have direct clinical relevance; one (El-Zahaar 1995) involving a mixed population of orthopaedic patients did not provide separate data for hip fracture patients; and one (Dyson 1988) with a factorial design which focused on a comparison outside the review scope, did not provide any results for the spinal versus general anaesthesia comparison. Further details of these are given in the Characteristics of Excluded Studies table. The one trial (Wajima 1995) in Studies Awaiting Assessment awaits translation from Japanese. A request has been sent to the contact author for further details of the study.

The 21 included trials involved a total of 2484 predominantly female and elderly hip fracture patients. Translations were obtained for three trial reports in French and one in German. Seventeen trials were published as full reports in peer-reviewed journals; the four exceptions (Brichant 1995; Eyrolle 1998; Tasker 1983; Ungemach 1993) being only available as conference abstracts. Two trial reports were available for Davis 1981, one of which focused on a sub-group of patients monitored for deep vein thrombosis. Four references, one again which focused on a sub-group of patients monitored for deep vein thrombosis, were available for McKenzie 1984. Though these at first appeared to be reports of separate trials, further details supplied by another trialist indicated that all the references applied to one study.

Seventeen included trials involving 2305 patients compared spinal or epidural anaesthesia with general anaesthesia. One study (White 1980) of 40 patients, which compared a 'light' general anaesthetic in conjunction with spinal anaesthesia versus general anaesthesia, is considered separately. A further group of 20 patients in this study were allocated to receive a psoas nerve block in conjunction with general anaesthesia, which is outside the scope of this review but included in another Cochrane review on localised nerve blocks (Parker 2001). Two newly included studies compared spinal anaesthesia with nerve blocks (de Visme 2000; Eyrolle 1998). The remaining trial (Spreadbury 1980) compared ketamine anaesthesia with inhalation general anaesthesia in 60 patients.

Further details of the individual trials are given in the Characteristics of Included Studies table.

Additional information on trial methodology and results would be welcomed from the authors of any of the studies, or from authors of trials which have not been identified.

Methodological quality

Treatment allocation was considered to be definitely concealed (Cochrane code A) in only one study (McKenzie 1984), which used sealed envelopes and random numbers. Allocation concealment was possible (Cochrane code B) in a further five studies (Brown 1994; Couderc 1977; de Visme 2000; Maurette 1988; Racle 1986) which gave incomplete details of their methods of randomisation, as well as the 14 studies which did not provide any details. Allocation was not concealed in the only overtly quasi-randomised trial (Adams 1990) which allocated treatment by the date of operation.

The methodology scores using the scoring system described earlier were:

REGIONAL VERSUS GENERAL ANAESTHESIA
1 2 3 4 5 6 7 8 9 Total (maximum 11)
-------------------------------------
0 0 0 1 0 0 0 0 1 2 Adams 1990
1 1 0 1 1 1 1 1 0 8 Berggren 1987
1 1 0 1 1 1 1 1 0 7 Bigler 1985
1 1 0 1 1 1 0 0 1 6 Bredahl 1991
1 1 0 0 0 1 1 0 0 4 Brichant 1995
2 1 0 1 0 1 0 0 1 6 Brown 1994
1 1 0 1 1 1 0 0 1 6 Davis 1981
2 1 0 1 0 1 0 1 0 6 Davis 1987
1 1 0 1 1 1 1 0 0 6 Juelsgaard 1998
2 1 0 1 0 1 0 0 1 6 Maurette 1988
1 0 0 1 0 1 0 0 1 4 McLaren 1978
3 0 0 0 0 1 0 1 1 6 McKenzie 1984
2 1 0 0 1 1 0 1 1 7 Racle 1986
1 0 0 0 0 1 0 0 0 2 Tasker 1983
1 0 0 0 0 0 0 0 0 1 Ungemach 1993
1 1 0 1 0 1 1 1 1 7 Valentin 1986

'LIGHT' GENERAL ANAESTHESIA COMBINED WITH SPINAL ANAESTHESIA VERSUS GENERAL ANAESTHESIA
1 2 3 4 5 6 7 8 9 Total
-------------------------------------
1 1 0 1 0 1 0 0 0 4 White 1980

REGIONAL (SPINAL) ANAESTHESIA VERSUS LOCAL NERVE BLOCKS
1 2 3 4 5 6 7 8 9 Total
-------------------------------------
2 1 0 1 1 1 0 0 1 7 de Visme 2000
1 0 0 0 0 0 0 0 1 2 Eyrolle 1998

KETAMINE VERSUS GENERAL ANAESTHESIA
1 2 3 4 5 6 7 8 9 Total
-------------------------------------
1 1 0 1 1 0 0 0 1 5 Spreadbury 1980

Two items meriting specific comment are items 3 (intention to treat) and 7 (assessor blinding). No trial satisfied the criteria for the first item, either because no information was available for patients withdrawn from the study or because those who had been withdrawn or excluded were not included in the baseline or outcome analyses, or because an intention to treat analysis was not done. The extent of assessor blinding was usually limited to select outcomes in most of the trials scoring on this item.

Results

The outcome measures listed earlier were extracted for each study and, where appropriate data were available, summarised in the analysis tables. The results are presented using the fixed effects model except where there is statistically significant heterogeneity between study results (P < 0.1) where the random effects model is applied. Since the primary outcome for this review, as stated in the protocol, is mortality, this is considered first. Other outcomes are presented in the categories listed under Types of outcome measures; these include surrogate or intermediate outcomes, such as peri-operative hypotension, body temperature and arterial blood gases. Although such outcomes may be predictive of important clinical outcomes, the relationship is usually not an exact one and some conditions, such as operative hypotension, may be remedied to reduce the risk of a serious clinical event occurring. Thus the results of such outcomes are not accurate guides of 'hard' clinical outcomes and may be misleading.

REGIONAL VERSUS GENERAL ANAESTHESIA

Mortality

Mortality was reported in most studies, except for four short-term studies (Bredahl 1991; Brichant 1995; Brown 1994; Maurette 1988), whose primary foci were body temperature, deep vein thrombosis, oxygen saturation and psychological evaluation respectively. Where possible, data for mortality up to one, three, six and twelve months were deduced or extracted from study reports, and pooled, for these four pre-specified time periods. Data for three months and beyond were extracted from graphs for two studies (Davis 1987; Valentin 1986). Additional mortality data were obtained for McKenzie 1984 from another trialist. Mortality data for undefined follow-up periods, or for under one month were provided by four studies (Adams 1990; Bigler 1985; Tasker 1983; Ungemach 1987). The data for the first two studies, which were for early deaths during hospital stay, and those for Ungemach 1987, which were at two weeks, were pooled with those for one month in an extra analysis. Tasker 1983 reported, without providing denominators, that the difference in mortality was not statistically different between the two groups (4 versus 6).

Results for all these studies are shown in the analyses tables. The reduced mortality for regional anaesthesia at one month (53/781 (6.8%) versus 78/826 (9.4%)) was of borderline statistical significance when evaluated using the fixed effects method (relative risk (RR) 0.72, 95% confidence interval (CI) 0.51 to 1.00), but not statistically significant when using the random effects model (RR 0.73, 95% CI 0.47 to 1.12). There was a similar pattern when the results from the three studies (Adams 1990; Bigler 1985; Ungemach 1987), which provided data on deaths during hospital stay or under one month, were pooled with the data for one month mortality (see analysis). The difference in mortality between the two groups was smaller and not statistically significant at subsequent follow-up times. The number of trials and associated data for pooling shrank at each time interval, with only the two largest trials (McKenzie 1984; Valentin 1986) contributing to the 12 month analysis. Mortality at three months appeared marginally less in the regional anaesthesia group (86/726 (11.8%) versus 98/765 (12.8%), RR 0.92, 95% CI 0.71 to 1.21), but slightly greater at six months (103/613 (16.8%) versus 115/651 (16.1%), RR 1.04, 95% CI 0.81 to 1.33) and 12 months (80/354 (22.6%) versus 78/372 (21.0%), RR 1.07, 95% CI 0.82 to 1.41).

Other outcomes:

a) Peri-operative outcomes

Length of operation
Most studies that recorded this outcome reported a statistically non-significant increase in the time taken to complete the operation for regional anaesthesia (Adams 1990; Berggren 1987; Bigler 1985; Maurette 1988; McKenzie 1984; Racle 1986). One study had a non-significant increase for general anaesthesia (Bredahl 1991) and three studies found no difference between the two groups (Davis 1981; Juelsgaard 1998; White 1980). Pooling of data from six studies showed a statistically significant increase of around five minutes for regional anaesthesia (weighted mean difference 4.8 minutes, 95% CI 1.1 to 8.6 minutes).

Hypotension
The definition of hypotension, when stated, was a greater than: 30 per cent reduction in systolic blood pressure (Berggren 1987), 33 per cent fall (Juelsgaard 1998), 40mmHg fall (Couderc 1977), and 20 per cent fall from the baseline in three studies (Davis 1987; Maurette 1988; Racle 1986).

Two studies (Adams 1990; Davis 1981) stated, without data for pooling, that the drop in systolic blood pressure was significantly greater in the regional anaesthesia group. Bigler 1985 reported no significant difference in the maximum drop of systolic blood pressure (48 versus 51mmHg). Pooling of data from eight studies (Berggren 1987; Brown 1994; Couderc 1977; Davis 1987; Juelsgaard 1998; Maurette 1988; McLaren 1978; Racle 1986) showed hypotension to be more common after regional anaesthesia. This difference was statistically significant when viewed using the Peto fixed effects method (158/441 (35.8%) versus 125/461 (27.1%), RR 1.31, 95% CI 1.09 to 1.58), but not when adopting the random effects model (RR 1.18, 95% CI 0.87 to 1.60) which is more probably more appropriate given the significant heterogeneity of trial results (chi-square = 11.28, P = 0.08). An exploration of the effect of removing each of the trials in turn from the analysis revealed that the removal of the data from Couderc 1977 produced the most homogeneous result (chi-square = 0.32). Although this may reflect the different definition of hypotension in this trial, there are too many other reasons to be certain that this is the case.

Operative blood loss
Pooled data for three studies (Bredahl 1991; Davis 1981; McKenzie 1984) show a statistically non-significant increase in operative blood loss for general anaesthesia (weighted mean difference 81ml, 95% CI -53 to 216ml). Five other studies contained insufficient data to enable pooling. Adams 1990 and Juelsgaard 1998 reported a non-significant increase in blood loss for regional anaesthesia; McLaren 1978 reported no significant difference; Ungemach 1987 reported no difference; and Valentin 1986 reported a significantly increased blood loss in the general anaesthesia group.

Transfusion requirements
Seven studies gave data for blood transfusion, which are presented as either the numbers of patients who were transfused in three studies (Adams 1990; Bigler 1985; Davis 1981), or the mean volume of blood transfused (transfusion requirement) (Couderc 1977; Juelsgaard 1998; Maurette 1988; Racle 1986). Similar proportions of patients received transfusion in each group in the first three studies (63/108 (58.3%) versus 68/120 (56.6%)). In contrast the transfusion requirements were greater in the regional anaesthesia group but there was significant heterogeneity (chi square = 12.63, P < 0.01) in the trial results and the pooled result was not statistically significant (weighted mean difference 141ml, 95% CI -40 to 322ml). Juelsgaard 1998 reported statistically non-significantly lower mean values of blood volume transfused over the operative and peri-operative period for the regional anaesthesia group (237ml versus 257ml). Bigler 1985 reported the mean falls in haemoglobin to be greater in the regional anaesthesia group (22% versus 19%, not significant).

Pre- and post-operative arterial blood gases
The reports of six studies (Berggren 1987; Brown 1994; Couderc 1977; Davis 1981; McLaren 1978; McKenzie 1984) contained data for blood gases taken either pre-operatively, operatively or post-operatively. Berggren 1987 reported numbers of patients with post-operative arterial oxygen tension of less than 60mmHg and these are presented in an analysis table (10/28 (36%) versus 14/29 (48%), RR 0.74, 95% CI 0.40 to 1.38). Brown 1994, in a study of post-operative oxygen saturation in 20 patients, found significantly lower oxygen saturation for the group who received general anaesthesia. Davis 1981 reported that the general anaesthesia group showed a post-operative fall in oxygen saturation in the early post-operative period, which was not seen after regional anaesthesia. By the first post-operative day there was no significant difference between the two groups. McKenzie 1984 reported a significant decrease in the oxygen saturation at one hour post-operatively in those who received general anaesthesia compared with those who received regional anaesthesia. In contrast, two studies (Couderc 1977; McLaren 1978) reported no difference in the mean arterial oxygen or carbon dioxide tensions for the two types of anaesthesia.

Length of hospital stay
Most studies reporting this found no difference in the length of hospital stay. Juelsgaard 1998 observed that the results for hospital stay were affected by a lack of rehabilitation facilities. Adams 1990 reported 21 days for regional versus 20 days for general anaesthesia. Berggren 1987 stated there was no difference in length of hospital stay between the two groups. Davis 1987 reported an average of 16 days for both groups, and Racle 1986, 20 days for both groups. Valentin 1986 reported a median stay of 10 days for regional anaesthesia and 11 days for general anaesthesia. Finally, McKenzie 1984 recorded a mean of 38 days for regional anaesthesia against 43 days for general anaesthesia. Summation of the two studies which quoted standard deviations (McKenzie 1984; Racle 1986), shown in the analysis tables, demonstrated no difference in the length of hospital stay between groups (weighted mean difference -0.2 days, 95% CI -5.2 to 4.8 days).

Other peri-operative outcomes
Other peri-operative outcomes recorded were changes in body temperature (Bredahl 1991), serum catecholamine and endocrine levels (Adams 1990; Tasker 1983), ECG changes (Juelsgaard 1998) and time to ambulation (Bigler 1985; Valentin 1986). Ungemach 1993 used a scoring system which included level of consciousness, respiration, circulation, blood loss and laboratory tests.

Bredahl 1991, who recorded body temperatures of 30 patients, concluded that temperature changes during the peri-operative period were unrelated to the type of anaesthesia.

Adams 1990 reported raised serum adrenaline and noradrenaline levels at the end of the operation for a sub-group of 32 patients, the rise in levels being greater in those patients who received a general anaesthetic. Tasker 1983, in a study of 100 patients, reported a significantly greater increase in plasma noradrenaline and cortisol levels after general anaesthesia in comparison with regional anaesthesia. There was no report of intra-operative cardiac arrhythmias.

Juelsgaard 1998 reported a significant increase in the overall number of ST segment depressions for those in the spinal anaesthesia group (125 versus 16 events).

Bigler 1985 reported a significant reduction in the mean time from surgery to ambulation of 3.3 days after regional anaesthesia versus 5.1 days after general anaesthesia. Valentin 1986 however reported no difference in the time to ambulation for patients in the two groups.

Post-operative scores in Ungemach 1993 were reported as 'better' in the spinal group, but it was not clear by how much and how this was manifested.

b) Complications specific to the method of treatment

Davis 1981 was the only study to report on aspiration pneumonia, with two cases in the general anaesthesia group. These have been included under the complication of pneumonia. A persistent headache, lasting three days, in one person in the spinal anaesthesia group was noted in Bigler 1985. McLaren 1978 reported that there were no post-anaesthetic headaches. There was no mention within the included studies of other complications such as damage to the upper airways or mouth from general anaesthesia.

Failure of spinal anaesthesia, usually resulting in the secondary use of general anaesthesia, was reported in both studies conducted by Davis et al (Davis 1981; Davis 1987). Spinal anaesthesia, often performed by junior staff, was unsuccessful in eight out of 72 patients (11.1%) in Davis 1981 and in 30 out of 259 patients (11.6%) in Davis 1987. Davis 1987 also referred to a 10% failure rate in the study of Valentin 1986. The treatment of these spinal anaesthesia failures in the analyses presented by these three trials has further implications regarding intention to treat analysis. For instance, it may be that the excluded patients had different characteristics and outcomes than those patients in which spinal anaesthesia was successful. The eight patients in Davis 1981 were incorrectly analysed in the general anaesthesia group, whereas the 30 patients in Davis 1987 were analysed in the spinal anaesthesia group, and lastly, Valentin 1986 chose to exclude them from the analysis.

c) General post-operative complications

Data for most of the life threatening complications such as pneumonia, myocardial infarction, cerebral vascular accident, congestive cardiac failure and pulmonary embolism were only available as causes for deaths in many of the trial reports. To reflect this, the data from fatal events have been sub-grouped separately from those listed as complications, or not wholly associated with deaths, in trial reports.

Pneumonia
Pneumonia or 'chest infection' was reported in nine studies (Adams 1990; Berggren 1987; Bigler 1985; Davis 1981; Davis 1987; Juelsgaard 1998; McKenzie 1984; McLaren 1978; Racle 1986). Pooling of the results indicates no clear difference between the two anaesthetic methods (29/554 (5.2%) versus 31/581 (5.3%), RR 0.99, 95% CI 0.62 to 1.59).

Myocardial infarction
This complication was reported in six studies (Couderc 1977; Davis 1981; Davis 1987; Juelsgaard 1998; McKenzie 1984; Racle 1986). Summation of the results from five trials showed a non statistically significant reduction in myocardial infarction in the regional anaesthesia group (5/446 (1.1%) versus 8/471 (1.7%), RR 0.70, 95% CI 0.26 to 1.85).

Cerebrovascular accident
This complication was reported in seven studies (Berggren 1987; Bigler 1985; Couderc 1977; Davis 1981; Davis 1987; McKenzie 1984; Racle 1986). Pooling of results demonstrated a tendency to a lower risk with general anaesthesia but the difference was not statistically significant (10/529 (1.9%) versus 6/556 (1.1%), RR 1.51, 95% CI 0.64 to 3.57).

Congestive cardiac failure
This complication was reported in seven studies (Adams 1990; Berggren 1987; Bigler 1985; Davis 1981; Davis 1987; Juelsgaard 1998; Racle 1986). Pooling of data gave similar results for both groups (12/454 (2.6%) versus 12/477 (2.5%), RR 1.05, 95% CI 0.49 to 2.23).

Renal failure
Renal failure was reported in four studies (Adams 1990; Davis 1981, Davis 1987; Racle 1986). Summation of results in the analysis table demonstrated no difference between anaesthetic techniques (2/382 (0.5%) versus 3/414 (0.7%), RR 0.86, 95% CI 0.22 to 3.41).

Post operative cardiac arrhythmia
More abnormal cardiac rhythms were detected in the general anaesthesia group in Couderc 1977. However, Couderc 1977 reported that there was no difference in the overall electrocardiographic results; these included results for other peri-operative changes in the cardiogram.

Acute confusional state
This complication was reported in three small studies (Berggren 1987; Bigler 1985; Racle 1986). Summation of the limited results showed a non statistically significant reduction in the regional anaesthesia group (10/83 (12.0%) versus 19/84 (22.6%), RR 0.53, 95% CI 0.27 to 1.07).

Urine retention
Pooling of the data from the two studies (Berggren 1987; Bigler 1985) reporting this complication showed similar results for the two anaesthetic techniques (10/48 (20.8%) versus 10/49 (20.4%), RR 1.02, 95% CI 0.47 to 2.23).

Post-operative vomiting
Pooling of the data from the two studies (Bigler 1985; McLaren 1978) reporting this complication again showed similar results for the two anaesthetic techniques (2/46 (4.3%) versus 3/49 (6.1%), RR 0.70, 95% CI 0.12 to 3.94).

Deep vein thrombosis
Deep vein thrombosis was the primary outcome for one study (Brichant 1995), and for two subgroups of patients from a further two studies (Davis 1981; McKenzie 1984). Awareness of the risk of deep vein thrombosis was evident in several other studies who did not report this outcome, with various prophylactic interventions being deployed: Dextran 70 (Berggren 1987); early mobilisation (Bigler 1985); anti-vitamin K and early mobilisation (Couderc 1977); heparin and active movement (Racle 1986) and anti-embolic stockings (Valentin 1986). Patients in Brichant 1995 also received thromboembolic prophylaxis with low molecular weight heparin and anti-embolism stockings. Venography screening was used to detect deep vein thrombosis in two studies (Brichant 1995; McKenzie 1984) and fibrinogen scanning in Davis 1987. Pooled data, grouped by method of diagnosis, include two deaths whose underlying cause was deep vein thrombosis from McLaren 1978. Significantly fewer thromboses were detected in patients in the regional anaesthesia group (39/129 (30%) versus 61/130(47%); RR 0.64, 95% CI 0.48 to 0.86). Though the difference in incidence rates was consistent between trials, whether measured by venography, fibrinogen update or at post-mortem, these results have to be viewed with caution since these were the results of subgroups of patients for whom data from venography or fibrinogen were available. In turn, the patients specially monitored for deep vein thrombosis were also subgroups of the trial populations in two studies (Davis 1981; McKenzie 1984).

Pulmonary embolism
Pulmonary embolism was reported in ten studies (Adams 1990; Berggren 1987; Bigler 1985; Brichant 1995; Couderc 1977; Davis 1981; Davis 1987; McKenzie 1984; McLaren 1978; Racle 1986) but mostly as a reason for death rather than through active monitoring for non-fatal pulmonary embolism. Pooling the results from nine studies using Peto odds ratios showed statistically significant heterogeneity (chi-square = 14.85, P = 0.06). Summation of results from nine studies using the random effects model to allow for this heterogeneity showed little difference in overall incidence of pulmonary embolism in the two groups (8/575 (1.4%) versus 10/609 (1.6%), RR 0.98, 95% CI 0.37 to 2.64). The source of heterogeneity resides mainly in the significantly different results in trials presenting solely results for fatal pulmonary embolism, and those presenting results for non-fatal pulmonary embolism. A second analysis, which presents these grouped by fatal and non-fatal pulmonary embolism, shows a contrasting and unexplained picture for these two outcomes (test for interaction, based on Peto odds ratio results: P = 0.004), where there is less fatal but more non-fatal pulmonary embolism in the regional anaesthesia group.

Composite outcome
Ungemach 1993 used a scoring system which included complications such as heart failure, thrombosis and apoplexy, as well as cardiopulmonary evaluation and laboratory tests. No difference between the two groups was found in the scores at two weeks.

d) Final outcome measures

Mortality has already been considered above.

Changes in mental function
Two studies (Bigler 1985; Maurette 1988) reported on long term changes in mental function. Bigler 1985 reported that there was no persistent impairment in mental function, and no significant differences between the two groups in the mental scores achieved at three months. Maurette 1988 performed psychological evaluations on 33 patients and found no significant difference relating to the type of anaesthesia.

Functional outcome
No study reported on the difference in functional outcomes between groups. Only McKenzie 1984 provided limited data on the location of patients at 12 months, but not for the return of patients to their previous residence.

'LIGHT' GENERAL ANAESTHESIA COMBINED WITH SPINAL ANAESTHESIA VERSUS GENERAL ANAESTHESIA

The only study (White 1980) in this category involved only 20 patients in each group. No patients died within the one month follow-up period of the study. The mean length of operation was 58 minutes in both groups. There was no significant difference in the mean post-operative blood oxygen or carbon dioxide levels between the two groups. Complications reported were pneumonia (4 versus 5 cases), confusional states (3 in each group), deep vein thrombosis (1 in the general anaesthesia group) and post-operative vomiting (1 in each group). Results for most of these outcomes are presented in the analysis tables.

REGIONAL (SPINAL) ANAESTHESIA VERSUS LOCAL NERVE BLOCKS

Two studies, involving 79 patients, were included. One study (Eyrolle 1998) compared spinal anaesthesia with a lumbar plexus block in 50 patients; supplementary intravenous propofol sedation was performed when necessary. The other study (de Visme 2000) compared spinal anaesthesia with a lumbar plexus block in conjunction with a sacral plexus block and iliac crest block (for lateral cutaneous nerve of the thigh). Intravenous alfentanil or sedatives were also used if necessary. Both studies only reported on outcome during the peri-operative period and did not report on post-operative complications or mortality. Results where available and appropriate are given in the analysis tables.

In Eyrolle 1998, the need for propofol supplementation, of dosage greater than 1mg/kg/hr, was significantly less common in the spinal group (5/25 versus 19/25). No cases of incomplete or unsatisfactory anaesthesia in the spinal group were reported in de Visme 2000 as opposed to four cases of incomplete anaesthesia and one case, requiring repeated sedation that was judged as unsatisfactory, in the nerve block group (0/14 versus 5/15). Overall, the need for supplementary sedation was significantly less in the spinal group (5/39 versus 24/40; RR 0.23, 95% CI 0.10 to 0.50).

A fall in mean arterial blood pressure of more than 20 per cent occurred in significantly more patients in the spinal group (18/25 versus 3/25; RR 6.0, 95% CI 2.02 to 17.83) in Eyrolle 1998. The mean fall in arterial blood pressure was also significantly greater in the spinal group in de Visme 2000 (mean difference 16mmHg, 95% CI -1.3 to 30.7mmHg). In both trials, significantly higher doses of ephedrine were used to stabilise blood pressure in the spinal group (weighted mean difference 5.96mg, 95% CI 4.46 to 7.45mg).

Pain as measured by the visual analogue scale (VAS) was stated as showing no difference between groups in Eyrolle 1998. Eleven patients failed to complete VAS in de Visme 2000, who considered that VAS rating for pain was unsatisfactory when there were cases of "sensorial" deficiency.

Insertion difficulty was significantly more common in the spinal group in Eyrolle 1998 (10/25 cases versus 3/25). In contrast, the mean time to administer the spinal was reported as being statistically significantly lower in the spinal group in de Visme 2000 (12 versus 18 minutes; reported p = 0.013).

Adverse effects, including five cases of urinary retention, were more common in the spinal group in Eyrolle 1998 (6/25 versus 1/25; RR 6.00, 95% CI 0.78 to 46.29). No adverse effects of the techniques were reported by de Visme 2000.

Post-operatively, similar numbers of patients had impaired cognitive function in de Visme 2000 (5/14 versus 6/15); this was reflected in the comparable mini-mental test scores (mean 15.5 versus 14.5).

KETAMINE VERSUS GENERAL ANAESTHESIA

The only study included in this category (Spreadbury 1980) involved 60 female patients. The limited results available are summarised in the analysis tables. Data were presented for early deaths (within 14 days) and late deaths (time unspecified, in hospital). These showed no difference in the overall mortality during hospital stay (9/30 (30%) versus 9/30 (30%)). Data presented for the complications of myocardial infarction (1 case), congestive cardiac failure (2 cases) and pulmonary embolism (3 cases) were all derived from causes of death for the seven early deaths.

The mean length of hospital stay for the 39 patients who returned home was 36 days for the ketamine group against 24 days for the general anaesthesia group. This difference is statistically significant and is related to the higher incidence of unsatisfactory surgical results in the ketamine group (see below). Although the general anaesthesia group mobilised more quickly than the ketamine group, Spreadbury 1980 reported that the differences were not statistically significant. The proportions of patients who returned home were similar (19/30 versus 20/30).

Spreadbury 1980 also reported that the numbers of patients who experienced dreams and hallucinations were similar for the two groups (4 versus 5 patients). They stated however that the dreams were more likely to be unpleasant after general anaesthesia. Spreadbury 1980 also reported the incidence of unsatisfactory surgical results, either due to later dislocation of the prosthesis or an unstable fixation, which subsequently required bed rest or traction. There were 7/30 (23%) such cases for the ketamine group against 3/30 (10%) for general anaesthesia.

Discussion

REGIONAL VERSUS GENERAL ANAESTHESIA

Many of the studies within this review involved small numbers of patients and reported only a few outcome measures. The trial reports of all studies indicated a poor level of methodological rigour, in particular regarding concealment of allocation, assessor blinding and intention to treat analysis. Despite these limitations, there is a reasonable agreement between trials for many of the outcome measures reported, particularly for mortality. It remains possible that some of the differences in outcome within the studies could be related to the differences in the experience, and competence, of the anaesthetists. Inexperience with the anaesthetic techniques could be inferred in some studies. For example, there was a high failure rate of spinal anaesthesia, often performed by junior staff, of over 11 per cent in both Davis 1981 and Davis 1987. However, there was no evidence that the seniority of the anaesthetists applying the different methods of anaesthesia differed in any given trial.

Hip fractures occur predominantly in the frail elderly who have multiple other medical conditions. The high mortality within this group of patients often results from these other medical conditions rather than being a direct consequence of the hip fracture and its treatment. Regional anaesthesia may reduce short-term mortality, yet this finding is borderline in that it is statistically significant when using the fixed effects model but not with the random effects model. The three month mortality results retain a potential for a reduction in mortality in the regional anaesthesia group; these are consistent with up to a 30 per cent reduction (95% CI 0.71 to 1.21). There is no evidence of substantial differences between regional and general anaesthesia in terms of long-term mortality, although the small numbers of patients with long-term follow-up, available from two trials of poor methodology, means that we cannot exclude clinically relevant differences. It would not be unexpected that changing one aspect of hip fracture treatment (the type of anaesthesia) did not substantially affect long-term mortality. Potentially, regional anaesthesia could enable the group of very frail elderly to survive the initial surgery, only for death to ensue later from other medical complications.

Because of the low incidence of many of the complications following surgery, no individual study had numbers large enough to determine if any difference exists. As much of the data for many of these complications was for fatal complications, these results are far from complete. Some possible, although unconfirmed, trends for regional anaesthesia were for less myocardial infarction, more cerebrovascular accidents and less fatal pulmonary embolism but more non-fatal pulmonary embolism. Although there were fewer cases of acute confusion when regional anaesthesia was used, more evidence is required to draw valid conclusions.

Pooled results for deep vein thrombosis showed a statistically significant reduction in the incidence of deep vein thrombosis in the regional anaesthesia group. This should not be considered conclusive as the data were from subgroups of patients who had been 'selected' by their compliance with a method of diagnosis, and thus the effect, and certainly the effect size, may have been distorted. The effects of thromboembolic prophylaxis may also affect the incidence of thromboembolic complications. The routine use of thromboembolic prophylaxis was mentioned in six studies (Berggren 1987; Bigler 1985; Brichant 1995; Couderc 1977; Racle 1986; Valentin 1986). It is also possible that thromboembolic prophylaxis may have been withheld in those receiving regional anaesthesia in some studies. The results do suggest a trend towards a reduced risk of thromboembolic complications with regional anaesthesia but, because of the small number of trials that reported this outcome and the heterogeneity of results, firm conclusions cannot be made for this outcome.

As would be expected from clinical practice, operations with regional anaesthesia were found to take approximately 5 to 10 minutes longer than general anaesthesia. This may be due to the time taken to administer the regional anaesthesia and then the time taken for the analgesic effect to occur. Regional anaesthesia results in vasodilatation of the lower limbs and this results in an increased tendency to operative hypotension, as demonstrated by the results. In addition, the increased blood flow to the lower limbs with alterations in coagulability and viscosity of the blood, may be the reason for the reduced incidence of venous thrombosis. It is possible that the benefits of the reduced thromboembolic complications may be negated if thromboembolic prophylaxis is used.

There was a tendency for more hypotension with regional anaesthesia. This may result in a predisposition to an increased incidence of cerebrovascular complications as hypotension is one of the aetiological factors for this complication. However, there are insufficient data to confirm this in this review and the care that needs to be taken in the interpretation of surrogate outcomes, such as hypotension, has already been mentioned (see start of Results).

Juelsgaard 1998 specifically targeted patients with known coronary artery disease. Whilst appropriate, the numbers of patients in the trial were too small to determine which type of anaesthesia is best for this specific patient population.

No attempt was made at a cost evaluation within any of the trials. Regional anaesthesia is cheaper with respect to drug costs incurred during the administration of the anaesthetic, but the time taken for a regional anaesthesia is slightly longer.

In their comprehensive review of regional anaesthesia, Rodgers et at (Rodgers 2000) found that post-operative mortality up to 30 days was significantly reduced for all types of surgery (general, orthopaedic, urological and vascular) and concluded that their findings supported a "more widespread use of neuraxial blockade [spinal / epidural anaesthesia]". It was notable that over half the trials with at least 10 deaths per trial involved patients with hip fracture; thus enhancing the contribution of the findings of these trials to the overall result. Rodgers 2000 considered that a lack of statistical power in individual trials and meta-analyses could be the principal reason for a conclusion that "neuraxial blockade had no important effect on mortality". In fact, our conclusions are phrased in a more tentative way than Rodgers et al imply and, although there is a lack of statistical power in our review, we also consider that there is an important lack of longer term outcome data. Like Rodgers 2000 we consider further research is warranted.

'LIGHT' GENERAL ANAESTHESIA COMBINED WITH SPINAL ANAESTHESIA VERSUS GENERAL ANAESTHESIA

The sole study to address this question (White 1980) involved only 20 patients in each group. There was no difference between techniques for any of the outcome measures reported. Because of the small numbers of patients involved, no conclusions about the lack of difference between the two techniques can be made.

REGIONAL (SPINAL) ANAESTHESIA VERSUS LOCAL NERVE BLOCKS

The two included trials (de Visme 2000; Eyrolle 1998) involved only 79 patients in total. In addition there was incomplete reporting of outcomes and no follow-up of patients. The limited results available suggest that the local nerve blocks are associated with a reduced risk of operative hypotension but have a greater risk of incomplete or unsatisfactory analgesia. Because of the limited information, no conclusions can be made on the use of nerve blocks compared with spinal anaesthesia.

KETAMINE VERSUS GENERAL ANAESTHESIA

The sole trial (Spreadbury 1980) comparing ketamine with general anaesthesia involved only 60 patients. The only key difference was a reduction in the 14-day mortality for ketamine, which related to a reduction in the risk of early fatal thromboembolic complications. However, this difference in mortality did not persist, and the mortality during hospital stay was equal in both groups. The numbers of patients were too small to show if the increase in 'unsatisfactory surgical results' in the ketamine group was a significant factor of ketamine use.

Reviewers' conclusions

Implications for practice

Both regional and general anaesthesia produce comparable results and therefore the anaesthetists should choose which technique is most appropriate for each individual patient. Regional anaesthesia may be preferable for those patients at high risk for thromboembolic complications.

Due to the limited data available, it is not possible to determine the roles of nerve blocks, ketamine or spinal anaesthesia with 'light' general anaesthesia for hip fracture anaesthesia.

Implications for research

Well designed randomised trials, with active follow-up of at least six months, of regional versus general anaesthesia involving large numbers of patients and which record, at minimum, the primary clinical outcomes of death, post-operative complications, and long term outcomes, would help clarify the relative merits of regional and general anaesthesia. Large trials with sub-group analysis may be able to determine if patients with specific medical conditions (such as cardiac disease, previous stroke) are better managed with one of these two forms of anaesthesia.

Potential conflict of interest

None known.

Acknowledgements

We would like to thank the following for useful comments from editorial review of the original review: Gordon Drummond (Department of Anaesthetics, University of Edinburgh), William Gillespie, Rajan Madhok, Gordon Murray, Tom Pedersen (Department of Anaesthesiology, Copenhagen University Hospital) and Marc Swiontkowski. We thank William Gillespie, Leeann Morton and Lesley Gillespie for their help with the first update. For this update, we are indebted to Lesley Gillespie, William Gillespie, Peter Herbison, Leeann Morton, Tom Pedersen, Janet Wale and Tony Wildsmith for their assistance and helpful feedback at editorial review.

Notes

This review and first update was published under the title: "General versus spinal/epidural anaesthesia for surgery for hip fractures in adults". The title was changed in the second update to reflect an expansion in the scope of the review to include comparisons of all forms of anaesthesia.

This review was first updated in Issue 4, 2000. The trial search was updated to August 1999 and one small trial (Juelsgaard 1999) was included. A consumer synopsis was added and relative risks instead of Peto odds ratios were presented for dichotomous outcomes. There were no significant changes to the conclusions of the review.

The second update appeared in Issue 4, 2001. This included one trial (Ungemach 1993) comparing general versus spinal anaesthesia, and two trials (Eyrolle 1998; de Visme 2000) which compared spinal anaesthesia with lumbar plexus blocks. There were no significant changes to the conclusions of the review.

Characteristics of included studies

Study Adams 1990
MethodsQuasi-randomised trial: by the date of operation
Methodological score: 2
ParticipantsOrthopaedic hospital in Gieben, Germany
56 patients with a proximal femoral fracture.
Mean age 79/81 years (range 63-91).
Male: 18%
Number lost to follow-up: not stated
InterventionsSpinal anaesthesia using 0.5% bupivacaine and 4% mepivacaine
versus
General anaesthesia using thiopentone, halothane, nitrous oxide/oxygen, vencuronium, succinycholine, atropine
OutcomesLength of follow-up: period of hospital stay
Mortality - during hospital stay
Length of operation
Hypotension
Operative blood loss
Transfusion requirements
Length of hospital stay
Blood levels of catecholamines, ADH and adrenalin (see notes)
Pneumonia (f)
Congestive cardiac failure (f)
Renal failure
Pulmonary embolism (f)
NotesPublished in German
Abstract and diagrams are contradictory for endocrine (ADH, adrenalin) results
Allocation concealmentC
Study Berggren 1987
MethodsRandomised trial: method not stated
Methodological score: 8
ParticipantsOrthopaedic hospital in Umea, Sweden.
57 patients with a femoral neck fracture
Mean age 77/78 years (range 65-92 years).
Male: 19%
Number lost to follow-up: 4 (7%)
InterventionsBoth groups premedicated with pethidine 25-50mg.
Spinal anaesthesia with 2% prilocaine in the epidural space, mean volume used 12.5ml
versus
General anaesthesia with thipopentone 3-4mg/kg, atropine 0.25-0.5mg iv, suxemethonium, ventilated with nitrous oxide and oxygen and halothane and suxamethonium infusion.
OutcomesLength of follow-up: 12 months
Mortality - 1 year (see notes)
Length of operation
Operative hypotension
Intraoperative blood loss (not split by treatment groups)
Hypoxaemia
Length of hospital stay
Pneumonia
Cerebrovascular accident
Congestive cardiac failure
Confusional state
Urine rention
Urinary tract infection
Pulmonary embolism
Total medical complications
Notes4 died by 1 year, 1 in the epidural group on 1st post-op day, the other 3 (group not given) by 5 months.
Patients were interviewed at 6 and 12 months regarding living conditions and walking ability - data not presented.
Allocation concealmentB
Study Bigler 1985
MethodsRandomised trial: method not stated
Methodological score: 7
ParticipantsPlace and country of study not stated
40 patients with a proximal femoral fracture
Mean age 79 years.
Male: 17.5%
Loss to follow-up: not known
InterventionsSpinal anaesthesia with 3ml of 0.75% bupivacaine
versus
General anaesthesia using atropine, thoiopentane, fentanyl, pancuronium, nitrous oxide/oxygen
OutcomesLength of follow-up: 3 months
Mortality - early
Length of operation
Hypotension (maximum drop in systolic blood pressure)
Transfusion requirements
Fall in haemaglobin
Pneumonia
Cerebrovascular accident
Congestive cardiac failure
Confusional state
Urine rention
Post-operative vomiting
Pulmonary embolism
Time till ambulation
Mental function
Headache
Notes 
Allocation concealmentB
Study Bredahl 1991
MethodsRandomised trial: method not stated
Methodological score: 6
ParticipantsOrthopaedic hospital Aalborg, Denmark
30 female patients with a proximal femoral fracture
Mean age 79 years (range 60-90).
Male: 0%
Loss to follow-up: not stated, but 2 excluded due to incomplete data.
InterventionsSpinal anaesthesia with 2.5-3ml of 0.5% bupivacaine
versus
General anaesthesia using thoiopentane, pethidine, pancuronium, nitrous oxide/oxygen, IPPV
OutcomesLength of follow-up: 3 days
Length of operation
Operative blood loss
Change in body temperature (up to 3 hours)
Notes 
Allocation concealmentB
Study Brichant 1995
MethodsRandomised trial: method not stated
Methodological score: 4
ParticipantsOrthopaedic hospital in Brussels, Belgium
106 patients with proximal femoral fracture
Age: not stated.
Male: % not stated
Number lost to follow-up: not stated
InterventionsSpinal (subarachroid or epidural) anaesthesia with bupivacaine
versus
General anaesthesia administered according to 'local practice'
OutcomesLength of follow-up: 10 days
Deep vein thrombosis (venography)
Pulmonary embolism
Haemorrhagic complications
Thrombocytopenia
NotesConference abstract only
All patients had subcutaneous nadroparin for DVT prophylaxis
Allocation concealmentB
Study Brown 1994
MethodsRandomised trial: use of random numbers table
Methodological score: 6
ParticipantsOrthopaedic hospital in Hong Kong
20 patients with a proximal femoral fracture
Mean age 77 years (range 66-91).
Male: 50%
Number lost to follow-up: not stated
InterventionsSpinal (subarachnoid) anaesthesia with 0.2mg/kg 0.5% bupivacaine
versus
General anaesthesia using thiopentone or propofol, isoflurane or enflurane and pre-medication with pethidine or temazepam
OutcomesLength of follow-up: 2 days (up to 44 hours)
Hypotension
Oxygen saturation
Notes 
Allocation concealmentB
Study Couderc 1977
MethodsRandomised study: by 'drawing of lots'
Methodogical score: 4
ParticipantsOrthopaedic hospital in Paris, France
100 patients with a proximal femoral fracture
Mean age 86 years. (Inclusion criterion: 80+ years; range not stated).
Male: 14%
Number lost to follow-up: not stated
InterventionsSpinal anaesthesia with 0.5% bupivacaine and adrenaline
versus
General anaesthesia with thiopentone, pancuronium, dextromoramide or methoxyflurane, nitrous oxide/oxygen
OutcomesLength of follow-up: 3 months
Mortality - 11 days, 3 months
Hypotension
Transfusion requirements
Oxygenation and carbon dioxide levels
Myocardial infarction (f)
Cerebrovascular accident (f)
Pulmonary embolism (f)
NotesIn French
Complete data for fatal myocardial infarction, congestive heart failure and pulmonary embolism not provided.
Allocation concealmentB
Study Davis 1981
MethodsRandomised trial: method not stated
Methodological score: 6
ParticipantsOrthopaedic hospital Christchurch, New Zealand
132 patients with a proximal femoral fracture
Mean age 81/78 years (Inclusion criterion: 50+, range not given).
Male: 15%
Number lost to follow-up: 0
InterventionsSpinal anaesthesia using tetracaine 0.5% in 51 patients and 0.5% cinchocaine in 13 patients. Ketamine also used for sedation in 8 patients and diazapam (mean dose 9mg).
versus
General anaesthesia with diazapam (2.5-30mg) mean dose 9.5mg. Fentanyl 1-3mcg/kg, nitrous oxide and oxygen, IPPV, pancuronium mean dose 6mg.
OutcomesLength of follow-up : 1 month
Mortality - 1 month
Duration of anaesthesia (Length of operation)
Postoperative blood gases
Hypotension
Operative blood loss
Fall in haematocrit
Pneumonia (f)
Aspiration pneumonia (f)
Myocardial infarction (f)
Cerebrovascular accident
Congestive cardiac failure
Renal failure
Cardiac arrthymias
Deep vein thrombosis (fibrinogen)
Pulmonary embolism (f)
Notes8 failed spinals who had a general anaesthesia were placed in the general anaesthesia group.
Results for DVT were available for 76 out of a sub-group of 90 patients who were monitored using I125 fibrogen scanning
Allocation concealmentB
Study Davis 1987
MethodsRandomised trial: method not stated
Methodological score: 5
ParticipantsOrthopaedic hospitals in New Zealand - multicentre study
549 patients with a proximal femoral fracture
Mean age 79.5 years (range not stated).
Male: 22%
Number lost to follow-up: 0, but 11 excluded
InterventionsSpinal anaesthesia with sedation with diazapam. Tetracaine, nupercaine or bupivacaine for spinal
versus
General anaesthesia with pre-oxygenation, iv induction with thiopentone, IPPV maintained with nitrous oxide/oxygen, non-depolarizing neuromuscular blocker, fentanyl
OutcomesLength of follow-up: 3 to 30 months
Mortality - 1 month, 3 & 6 months (estimated from graph)
Hypotension
Length of hospital stay
Pneumonia (f)
Myocardial infarction (f)
Cerebrovascular accident (f)
Congestive cardiac failure (f)
Renal failure (f)
Pulmonary embolism (f)
Notes11.3% of patients originally allocated to spinal anaesthesia were given general anaesthesia due to failed spinals. These were retained in the spinal group for analysis purposes.
There was 1 non fatal anaphylactoid reaction at induction of general anaesthesia
Allocation concealmentB
Study Eyrolle 1998
MethodsRandomised trial: method not stated
Methodological score: 2
ParticipantsOrthopaedic hospital in Paris, France
50 patients with a proximal femoral fracture
Mean age 82 years (range not stated)
Male: % not stated
Number lost to follow-up: none probably
InterventionsSpinal anaesthesia with 0.5% bupivacaine
versus
lumber plexus block using 2% lidocaine, 0.5% bupivacaine with 1:200,000 epinephrine.
A light sedation with propofol intravenously, as required.
OutcomesLength of follow-up: not stated
Ease of insertion
Hypotension
Use of propofol during surgery (associated with discomfort)
Use of epinephrine during surgery
Post-operative cognitive function
Pain levels post-operatively Adverse effects (including urinary retention)
NotesConference abstract only
Allocation concealmentB
Study Juelsgaard 1998
MethodsRandomised trial: method not stated
Methodological score: 6
ParticipantsOrthopaedic hospital in Aarhus, Denmark
29 followed-up out of 54 patients with proximal femoral fracture and known coronary artery disease
For 29 patients included in this review:
Age: mean 80.9 years (range 65-99)
Male: 13%
Number lost to follow-up: 0, but 11 excluded from original trial population
InterventionsSpinal anaesthesia with 2.5ml of 0.5% bupivacaine in the subarachnoid space
versus
General anaesthesia with fentanyl 1-2mcg/kg, 1-4mg/kg thiopentone, 0.5mg/kg atracurium, nitrous oxide and oxygen, enflurane.
OutcomesLength of follow-up: 1 month
Mortality - 1 month
Length of operation
Hypotension (33% reduction from baseline)
Peri and post operative blood loss
Transfusion requirements
Pneumonia (f)
Congestive cardiac failure (f)
Myocardial infarction
ECG analysis
Length of hospital stay
NotesThe study also included 14 patients allocated to incremental spinal anaesthesia. These patients have not been included in this review
Allocation concealmentB
Study Maurette 1988
MethodsRandomised trial: by 'random draw'
Methodological score: 6
ParticipantsOrthopaedic hospital Bordeaux, France
35 patients with a proximal femoral fracture
Mean age 83 years (range not stated).
Male: % not stated
Number lost to follow-up: not stated, but 2 excluded as they failed to participate in post-op tests
InterventionsSpinal anaesthesia with 1.5mg/kg prilocaine
versus
General anaesthesia using thiopentone, spontaneous ventilation, nitrous oxide/oxygen, enflurane, dextromoramide
OutcomesLength of follow-up: 3 days
Length of operation
Hypotension
Transfusion requirements
Psychological evaluation
NotesIn French
Allocation concealmentB
Study McKenzie 1984
MethodsRandomised trial: use of envelopes containing random numbers Methodological score: 6
ParticipantsOrthopaedic hospital in Glasgow, Scotland
150 patients with fractured neck of femur.
Mean age 75 years (range not stated).
Male: % not stated
Number lost to follow-up: 0, but 2 excluded due to postponement of operation
InterventionsSpinal anaesthesia with 0.5% hyperbaric cinchocaine 1.3-1.5ml. Supplemented by small doses of diazapam if required
versus
General anaesthesia induced with althesin 1-3ml, suxamethonium 50mg, nitrous oxide and oxygen, halothane and spontaneous respiration.
OutcomesLength of follow-up: 12 months
Mortality - at 1, 3, 6 and 12 months
Length of operation
Operative blood loss
Length of hospital stay
Pneumonia (f)
Myocardial infarction (f)
Cerebrovascular accident (f)
Deep vein thrombosis (venography)
Pulmonary embolism (f)
Location at 12 months
NotesAdditional information supplied by Dr McLaren indicated that all the references refered to one study. Additional data on mortality supplied.
The venography study for DVT detection involved a subgroup of 40 patients
Allocation concealmentA
Study McLaren 1978
MethodsRandomised trial: method not stated
Methodological score: 4
ParticipantsOrthopaedic hospital in Glasgow, Scotland
55 patients with fractured neck of femur
Mean age 76 years.
Male: % not stated.
Number lost to follow-up: 0
InterventionsNo premedicaton
Spinal anaesthesia with 0.5ml hyperbaric cinchocaine 0.5%. Patients sedated with 10% Althesin in 5% dextrose during operation.
versus
General anaesthesia with Althesin 50mcg/kg, Pancuronium bromide 0.1 mg/kg, IPPV, nitrous oxide, oxygen and Fentanyl 0.05mg as needed.
OutcomesLength of follow-up: 1 month minimum
Mortality - 1 month
Length of operation
Hypotension
Post-operative oxygenation
Blood loss
Pneumonia (respiratory infections)
Vomiting
Deep vein thrombosis (f)
Pulmonary embolism (f)
Headache (none)
NotesAddendum in paper indicated that data for a further 20 patients were available - there were 2 more deaths in the general anaesthesia group
Allocation concealmentB
Study Racle 1986
MethodsRandomised study: use of random numbers table
Methodological score: 6
ParticipantsOrthopaedic hospital in Cedex, France.
70 female patients with a proximal femoral fracture
Mean age: 82 years (Inclusion criterion: 75+, range not given).
Male: 0%
Number lost to follow-up: not stated
InterventionsSpinal anaesthesia with 3ml 0.5% Bupivacaine + adrenaline
versus
General anaesthesia using thiopentone, vecuronium, fentanyl, nitrous oxide/oxygen, enflurane
OutcomesLength of follow-up: 3 months
Mortality - 1, 3 months
Length of operation
Hypotension
Transfusion requirements
Length of hospital stay
Pneumonia
Myocardial infarction
Cerebrovascular accident (f)
Congestive cardiac failure
Renal failure (f)
Confused state
Pulmonary embolism
NotesIn French
Allocation concealmentB
Study Spreadbury 1980
MethodsRandomised: method not stated
Methodological score: 6
ParticipantsOrthopaedic hospital in Warwick, England
60 female patients with a proximal femoral fracture
Mean age 84 years (range not stated).
Male: % not stated
Number lost to follow-up: none
InterventionsKetamine anaesthesia using atropine pre-medication, ketamine 2mg/kg at induction then ketamine 1mg/kg as required
versus
General anaesthesia using premedication of atropine 0.6mg then a general anaesthetic using drugs and method chosen by the anaesthetist
OutcomesLength of follow-up: not stated
Mortality - 14 days, during hospital stay
Myocardial infarction (f)
Congestive cardiac failure (f)
Pulmonary embolism (f)
Time to mobilisation
Length of hospital stay
Return of patients back home
Occurrence of dreams or hallucinations after operation
Unsatisfactory surgical results
Notes 
Allocation concealmentB
Study Tasker 1983
MethodsRandomised trial: method not stated
Methodological score: 2
ParticipantsOrthopaedic hospital in Leicester, England
100 patients with a proximal femoral fracture.
Mean age not stated.
Male: % not stated
Number lost to follow-up: not stated
InterventionsSpinal versus general anaesthesia
Exact method of anaesthesia not stated
OutcomesLength of follow-up: not stated
Mortality
Plasma catecholamines, cortisol
NotesConference abstract only
Allocation concealmentB
Study Ungemach 1993
MethodsRandomised trial: method not stated, mention of pairs
Methodological score: 1
ParticipantsOrthopaedic hospital in Mannheim, Germany
114 patients with a proximal femoral fracture.
Mean age 79 years (range not stated).
Male: 16%
Number lost to follow-up: not stated
InterventionsSpinal anaesthesia with 3-4ml of 0.5% hyperbaric bupivacaine
versus
General anaesthesia with isoflurane, fentanyl, nitrous oxide/oxygen
OutcomesLength of follow-up: 2 weeks
Mortality - 2 weeks
Score based on conscious level, respiration, circulation, blood lost and laboratory tests taken at 2 hours.
Score based on lab tests, cardiopulmonary situation and complications (e.g. heart failure, thrombosis and apoplexy) at 2 weeks post-operatively
NotesConference abstract only
Allocation concealmentB
Study Valentin 1986
MethodsRandomised trial: method not stated
Methodological score: 7
ParticipantsOrthopaedic hospital in Hellerup, Denmark
662 patients with a proximal femoral fracture
Mean age 79 years (range 50 - 100).
Male: 20%
Number lost to follow-up: 2 (0.3%), 84 patients excluded
InterventionsSpinal anaesthesia with 3-4ml isotonic Bupivacaine and sedation with Fentanyl 0.05-0.1mg IV
versus
General anaesthesia with enflurane and nitrous oxide/oxygen with or without thiopentone at induction or neurolept anaesthesia with droperidol, fentanyl and nitrous oxide/oxygen
OutcomesLength of follow-up: 24 months
Mortality - 1 month, 3, 6 and 12 months (read from graphs)
Length of operation
Operative blood loss
Time to ambulation
Length of hospital stay
Notes 
Allocation concealmentB
Study White 1980
MethodsRandomised trial: method not stated
Methodological score: 4
ParticipantsOrthopaedic hospital in Cape Town, South Africa
40 of 60 patients in trial with a proximal femoral fracture.
Mean age 79 years (range not stated).
Male: 8%
Number lost to follow-up: 0
InterventionsSpinal anaesthesia with 0.6-0.8ml hyperbaric cinchocaine and 'light' general anaesthesia with althesin, fentanyl, nitrous oxide/oxygen
versus
General anaesthesia with thiopentone, suxamethonium, nitrous oxide/oxygen, halothane, fentanyl
versus
Psoas nerve block with 30ml 2% mepivacaine and 'light' general anaesthesia with fentanyl and althesin (not included in review)
OutcomesLength of follow-up: minimum 4 weeks
Mortality - 1 month
Length of operation
Post operative blood gases (oxygen and carbon dioxide)
Pneumonia
Confusional state
Deep vein thrombosis
Vomiting
NotesThe 20 Psoas nerve block group patients were not included in this review
Allocation concealmentB
Study de Visme 2000
MethodsRandomised trial: method by 'hospital pharmacy before transfer to the operating theatre'
Methodological score: 7
ParticipantsOrthopaedic hospital in Brest, France
29 patients with a proximal femoral fracture
Mean age 85 years (range 68-97).
Male: 17%
Number lost to follow-up: none
InterventionsSpinal anaesthesia with sedation using alfentanil and 3ml 0.5% plain bupivacaine for the spinal
versus
lumber plexus, sacral plexus and iliac crest block first with sedation using alfentanil. 30ml and 10ml of 1.33% lidocaine and epinephrine were used for the lumbar and sacral blocks and 5ml 1% lidocaine for the iliac crest block (for lateral cutaneous nerve).
OutcomesLength of follow-up: not stated but probably 5 days
Length of operation
Time to perform the anaesthetic
Hypotension
Use of epinephrine during surgery
Post-operative cognitive function
Pain levels in the recovery room
Need for supplemention of analgesia
Notes 
Allocation concealmentB

(f) = fatal: outcome such as pneumonia only appears as a reason for death

Characteristics of excluded studies

StudyReason for exclusion
Barna 1981Translation of the article from Hungarian revealed it is a comparative study of 100 spinal anaesthetics and 100 general anaesthetics for hip fracture patients. The study was excluded as there was no randomisation of patients.
Coleman 1988A randomised trial of 152 patients comparing general anaesthesia with spontaneous respiration with general anaesthesia with controlled ventilation. The study was excluded as it involved a change in the types of drugs used only, not a change in the method of anaesthesia.
Critchley 1995A randomised trial of 30 hip fracture patients comparing spinal anaesthesia with ephedrine alone or with ephedrine and colloid. The trial was excluded as it was not a trial of different types of anaesthesia but a comparison of different drugs within one form of anaesthesia.
Darling 1994A randomised trial of 10 patients with spinal anaesthetic and 10 with general anaesthesia to assess the rate of clearance of a bolus dose of Indocyanine green between the two anaesthetic techniques. There was no difference in the rate of disappearance of the indocyanine green between the two techniques and no other outcomes were reported. The study was excluded as it was not felt relevant to this review as no clinical outcomes were reported.
Dyson 1988A randomised trial of 60 patients which tested the use of postoperative oxygen in two groups that had already been divided into those receiving general anaesthesia and those receiving spinal anaesthesia. No results were provided for the anaesthetic comparison save the general statement that there was no statistical difference in mean oxygen tensions between the two anaesthesia groups. The trial was excluded due to the lack of outcome data for the anaesthesia comparison.
El-Zahaar 1995This study was a randomised comparison of general versus epidural anaesthesia in 214 patients undergoing either hip or femoral surgery (117 patients), or tibial surgery (97 patients). This trial was excluded because separate results for patients having surgery for a hip fracture were not presented.
Favarel 1996A randomised trial of 60 hip fracture patients comparing the haemodynamic effects of a single dose of spinal bupivacaine versus a continuous titrated dose. Outcome measures were the onset of anaesthesia and haemodynamic variables. The trial was excluded as it was not considered a comparison of different forms of anaesthesia, only of a modification of anaesthetic technique.
Maurette 1993A randomised trial of 34 hip fracture patients comparing continous spinal anaesthesia with lidocanine alone versus lidocaine with meperidine. The trial was excluded as it was a trial of different drugs with the same anaesthetic technique, not a comparision of different types of anaesthesia.
Owen 1982A randomised trial of a single dose of doxapram on the post-operative arterial oxygen tension in hip fracture patients. The trial was excluded as it was not a comparison of anaesthetic techniques.
Sinclair 1997A randomised trial of 40 patients with a hip fracture surgically treated under general anaesthesia. Patients were randomised to have either conventional intra-operative fluid management or colloid fluid challenges. The study was excluded as it was not a comparison of different types of anaesthesia.
Sutcliffe 1994A comparative study of 1333 patients with general versus spinal anaesthesia. The study was excluded as there was no randomisation of patients.
Tonczar 1981A randomised trial of 14 patients comparing neuroleptic anaesthesia with spinal anaesthesia. The study was excluded as it involved a neuroleptic anaesthesia and the only outcome measures were plasma catecholamines, cortisol, blood pressure and changes in heart rate.
Ungemach 1987A randomised trial of 50 hip fracture patients using either enflurane or enflurane and fentanyl. The trial was excluded as it was a comparison of different drugs within one type of anaesthesia (general anaesthesia) and not a comparison of different anaesthetic techniques.
Van Gessel 1989A randomised trial of 30 hip fracture patients comparing spinal anaesthesia with either hypobaric tetracaine or hypobaric bupivacaine. The trial was excluded as it was a not a trial of different types of anaesthesia but a comparison of different drugs within one form of anaesthesia.
Wickstrom 1982This was a report of two quasi-randomised trials (based on dates of birth) with a month in-between, reported as one study. The first study compared epidural versus ketamine intravenous infusion versus neurolept general anaesthesia in 129 hip fracture patients. The second study compared enflurane general anaesthesia versus halothane general anaesthesia in 40 hip fracture patients. The first study was excluded as it was considered that neuroleptic anaesthesia was no longer applicable or relevant for hip fracture surgery. A comparison of non-concurrent treatment groups was also not considered appropriate. The second study was excluded as it was a comparison of different drugs within one type of anaesthesia (general anaesthesia) and not a comparison of different anaesthetic techniques.

Graphs

Comparison 01. Regional (spinal or epidural) versus general anaesthesia
Outcome titleNo. of studiesNo. of participantsStatistical methodEffect size
01 Mortality - 1 month81607Relative Risk (Fixed) 95% CI0.72 [0.51, 1.00]
02 Mortality - 1 month (random effects model)81607Relative Risk (Random) 95% CI0.73 [0.47, 1.12]
03 Mortality - 3 months61491Relative Risk (Fixed) 95% CI0.92 [0.71, 1.21]
04 Mortality - 6 months31264Relative Risk (Fixed) 95% CI1.04 [0.81, 1.33]
05 Mortality - 12 months2726Relative Risk (Fixed) 95% CI1.07 [0.82, 1.41]
06 Mortality - early and up to 1 month111817Relative Risk (Fixed) 95% CI0.76 [0.56, 1.04]
07 Length of operation (mins)6376Weighted Mean Difference (Fixed) 95% CI4.82 [1.08, 8.56]
08 Operative hypotension8902Relative Risk (Fixed) 95% CI1.31 [1.09, 1.58]
09 Operative hypotension (random effects model)8902Relative Risk (Random) 95% CI1.18 [0.87, 1.60]
10 Operative blood loss (mls)3308Weighted Mean Difference (Random) 95% CI-81.24 [-216.01, 53.54]
11 Patients receiving blood transfusion3228Relative Risk (Fixed) 95% CI1.01 [0.82, 1.24]
12 Transfusion requirements (mls)3203Weighted Mean Difference (Random) 95% CI140.69 [-40.33, 321.71]
13 Post-operative hypoxia157Relative Risk (Fixed) 95% CI0.74 [0.40, 1.38]
14 Length of hospital stay2218Weighted Mean Difference (Fixed) 95% CI-0.21 [-5.21, 4.78]
15 Pneumonia91125Relative Risk (Fixed) 95% CI0.99 [0.62, 1.59]
16 Myocardial infarction5917Relative Risk (Fixed) 95% CI0.70 [0.26, 1.85]
17 Cerebrovascular accident71085Relative Risk (Fixed) 95% CI1.51 [0.64, 3.57]
18 Congestive cardiac failure7931Relative Risk (Fixed) 95% CI1.05 [0.49, 2.23]
19 Renal failure4796Relative Risk (Fixed) 95% CI0.86 [0.22, 3.41]
20 Acute confusional state3167Relative Risk (Fixed) 95% CI0.53 [0.27, 1.07]
21 Urine retention297Relative Risk (Fixed) 95% CI1.02 [0.47, 2.23]
22 Vomiting295Relative Risk (Fixed) 95% CI0.70 [0.12, 3.94]
23 Deep vein thrombosis4259Relative Risk (Fixed) 95% CI0.64 [0.48, 0.86]
24 Pulmonary embolism91184Relative Risk (Fixed) 95% CI0.90 [0.42, 1.94]
25 Pulmonary embolism (random effects model)91184Relative Risk (Random) 95% CI0.98 [0.37, 2.64]
26 Pulmonary embolism (fatal and non fatal)  Relative Risk (Fixed) 95% CISubtotals only
Figure 1.

01 Mortality - 1 month

Figure 2.

02 Mortality - 1 month (random effects model)

Figure 3.

03 Mortality - 3 months

Figure 4.

04 Mortality - 6 months

Figure 5.

05 Mortality - 12 months

Figure 6.

06 Mortality - early and up to 1 month

Figure 7.

07 Length of operation (mins)

Figure 8.

08 Operative hypotension

Figure 9.

09 Operative hypotension (random effects model)

Figure 10.

10 Operative blood loss (mls)

Figure 11.

11 Patients receiving blood transfusion

Figure 12.

12 Transfusion requirements (mls)

Figure 13.

13 Post-operative hypoxia

Figure 14.

14 Length of hospital stay

Figure 15.

15 Pneumonia

Figure 16.

16 Myocardial infarction

Figure 17.

17 Cerebrovascular accident

Figure 18.

18 Congestive cardiac failure

Figure 19.

19 Renal failure

Figure 20.

20 Acute confusional state

Figure 21.

21 Urine retention

Figure 22.

22 Vomiting

Figure 23.

23 Deep vein thrombosis

Figure 24.

24 Pulmonary embolism

Figure 25.

25 Pulmonary embolism (random effects model)

Figure 26.

26 Pulmonary embolism (fatal and non fatal)

Comparison 02. Spinal and 'light' general anaesthetic versus general anaesthetic
Outcome titleNo. of studiesNo. of participantsStatistical methodEffect size
01 Mortality - 1 month140Relative Risk (Fixed) 95% CINot estimable
02 Length of operation140Weighted Mean Difference (Fixed) 95% CI0.00 [-14.89, 14.89]
03 Pneumonia140Relative Risk (Fixed) 95% CI0.80 [0.25, 2.55]
04 Confusional state140Relative Risk (Fixed) 95% CI1.00 [0.23, 4.37]
05 Deep vein thrombosis140Relative Risk (Fixed) 95% CI0.33 [0.01, 7.72]
Figure 27.

01 Mortality - 1 month

Figure 28.

02 Length of operation

Figure 29.

03 Pneumonia

Figure 30.

04 Confusional state

Figure 31.

05 Deep vein thrombosis

Comparison 03. Regional (spinal or epidural) versus lumbar plexus nerve blocks
Outcome titleNo. of studiesNo. of participantsStatistical methodEffect size
01 Incomplete or unsatisfactory analgesia279Relative Risk (Fixed) 95% CI0.23 [0.10, 0.50]
02 Operative hypotension150Relative Risk (Fixed) 95% CI6.00 [2.02, 17.83]
03 Mean fall in arterial blood pressure (mmHg)129Weighted Mean Difference (Fixed) 95% CI16.00 [1.31, 30.69]
04 Mean dose of ephedrine used (mg)279Weighted Mean Difference (Fixed) 95% CI5.96 [4.46, 7.45]
05 Adverse effects279Relative Risk (Fixed) 95% CI6.00 [0.78, 46.29]
06 Post-operative confusion129Relative Risk (Fixed) 95% CI0.89 [0.35, 2.28]
Figure 32.

01 Incomplete or unsatisfactory analgesia

Figure 33.

02 Operative hypotension

Figure 34.

03 Mean fall in arterial blood pressure (mmHg)

Figure 35.

04 Mean dose of ephedrine used (mg)

Figure 36.

05 Adverse effects

Figure 37.

06 Post-operative confusion

Comparison 04. Intravenous ketamine versus general anaesthesia
Outcome titleNo. of studiesNo. of participantsStatistical methodEffect size
01 Mortality - during hospital stay160Relative Risk (Fixed) 95% CI1.00 [0.46, 2.17]
02 Myocardial infarction160Relative Risk (Fixed) 95% CI0.33 [0.01, 7.87]
03 Congestive cardiac failure160Relative Risk (Fixed) 95% CI0.20 [0.01, 4.00]
04 Pulmonary embolism160Relative Risk (Fixed) 95% CI0.14 [0.01, 2.65]
05 Length of hospital stay (discharge home)139Weighted Mean Difference (Fixed) 95% CI12.00 [5.57, 18.43]
Figure 38.

01 Mortality - during hospital stay

Figure 39.

02 Myocardial infarction

Figure 40.

03 Congestive cardiac failure

Figure 41.

04 Pulmonary embolism

Figure 42.

05 Length of hospital stay (discharge home)

Sources of support

External sources of support

  • Chief Scientist Office, Department of Health, The Scottish Office UK

Internal sources of support

  • No sources of support supplied

Ancillary