Needle gauge and tip designs for preventing post-dural puncture headache (PDPH)

  • Protocol
  • Intervention


  • Ingrid Arevalo-Rodriguez,

    Corresponding author
    1. Fundación Universitaria de Ciencias de la Salud, Hospital de San José/Hospital Infantil de San José, Division of Research, Bogotá D.C., Colombia
    • Ingrid Arevalo-Rodriguez, Division of Research, Fundación Universitaria de Ciencias de la Salud, Hospital de San José/Hospital Infantil de San José, Bogotá D.C., 11001, Colombia.

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  • Luis Muñoz,

    1. Hospital de San José, Fundación Universitaria de Ciencias de la Salud, Department of Anaesthesia, Bogotá D.C., Colombia
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  • Jimmy J Arevalo,

    1. VU University Medical Center, Department of Anesthesiology, Amsterdam, Noord Holland, Netherlands
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  • Agustín Ciapponi,

    1. Southern American Branch of the Iberoamerican Cochrane Centre, Argentine Cochrane Centre IECS, Institute for Clinical Effectiveness and Health Policy, Buenos Aires, Capital Federal, Argentina
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  • Marta Roqué i Figuls

    1. CIBER Epidemiología y Salud Pública (CIBERESP), Iberoamerican Cochrane Centre, Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Catalunya, Spain
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This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

To assess the effects of needle tip design and diameter (gauge) on prevention of post-dural puncture headache (PDPH) in patients who have undergone dural puncture for diagnostic or therapeutic causes.


Description of the condition

Post-dural (post-lumbar or post-spinal) puncture headache (PDPH) is one of the most common complications of diagnostic, therapeutic or inadvertent lumbar punctures (Bezov 2010; Davignon 2002; Raskin 1990; Sadashivaiah 2009). PDPH is defined as any headache after a lumbar puncture that worsens within 15 minutes of sitting or standing and is relieved within 15 minutes of the patient's lying down (González-Martínez 2005; Headache Classification Subcommittee IHS 2004). Most PDPHs occur within three days of the procedure, and more than 50% start within the first 48 hours (Turnbull 2003).

The pathophysiology of PDPH has not been fully established. It is well known that puncture of the dura allows cerebrospinal fluid (CSF) to leak from the subarachnoid space, which results in decreased CSF volume and pressure (Grande 2005). This CSF volume loss may cause a downward pull on pain-sensitive structures that can explain the occurrence of PDPH (Ahmed 2006; Baumgarten 1987; Davignon 2002; Denny 1987; Harrington 2004). In addition, loss of CSF may cause an increase in blood flow, leading to arterial and venous vasodilatation that can result in PDPH. A third PDPH mechanism may involve the role of substance P (neurotransmitter/neuromodulator involved in pain perception) and the regulation of neurokinin 1 receptors (NK1Rs) (Clark 1996). Defects in manufactured needles have also been described as a possible source of PDPH. Laboratory studies have shown significant alteration of the tips of cutting needles when their mandrels protrude through the inner hole of the needle. These altered tips can produce holes in the dura mater of increased diameter, which may require longer healing times and consequently increase the time allowed for leakage of CSF (Bezov 2010; Calthorpe 2004; Parker 1997).

Studies about the incidence of PDPH have reported a wide range of estimates, depending on target populations, types of needles and lumbar puncture techniques (Alstadhaug 2012). For example, during anaesthetic procedures such as epidural anaesthesia, PDPH is most commonly caused by an unintentional dural puncture (Thew 2008; Turnbull 2003). However, in diagnostic or therapeutic lumbar punctures, the need for adequate CSF flow requires an intentional lesion that may trigger the PDPH phenomenon (Kuczkowski 2006). Estimated frequencies of this event vary from less than 10% after spinal anaesthesia (Vallejo 2000) to 36% after diagnostic lumbar puncture (Lavi 2006; Vallejo 2000), and up to 81% in obstetrical patients with inadvertent dural puncture during active labour (Berger 1998; Choi 2003).

The characteristics of PDPH are often variable. It may be accompanied by neck stiffness, tinnitus, hearing loss, photophobia and nausea, among others. Other characteristics such as the location and duration of the headache are also unpredictable (Grande 2005). Although PDPH is not a life-threatening condition, physical activity is often restricted. Patients are usually required to stay in bed the entire day, and length of hospital stay and use of medical services are increased (Angle 2005). The variability in symptom profiles makes PDPH a diagnosis of exclusion. Alternative diagnoses (e.g. viral meningitis, sinus headache, intracranial haemorrhage) should be ruled out first (Turnbull 2003).

Once PDPH is diagnosed, initial treatment involves conservative measures such as bed rest and analgesics. If PDPH continues for longer than 72 hours, more specific treatment is indicated (Ahmed 2006). Severe PDPH may respond to some therapeutic drugs and to an epidural blood patch (Boonmak 2010; Lavi 2006).

Description of the intervention

Many interventions have been suggested for the prevention of PDPH (e.g. body postures and fluid intake after lumbar puncture). One of the most relevant strategies involves the features of needles (Arendt 2009). Although the choice of the needle depends mostly on the purpose of the lumbar puncture, several experts have remarked that facets such as the tip and the gauge could be modified to decrease the incidence of PDPH (American Society of Anesthesiologist 2007; Armon 2005).

According to tip design, needles can be divided into traumatic and atraumatic types. Atraumatic needles include Whitacre, Atraucan, Sprotte, Cappe and Deutsch, among others. Traumatic needles include Quincke, Greene, Hingson Ferguson, Lutz, Brace and Rovenstine, among others. Traumatic needles are characterized by a bevelled tip that cuts the dura mater. In contrast, modern atraumatic needles have a pencil-point design. It has been stated that noncutting or atraumatic needles produce a separation of the tissue fibres that heals easily after removal of the needle. Cutting or traumatic needles favour loss of tissue and trigger a large inflammatory reaction that requires a long time to heal (Calthorpe 2004; Lynch 1992; Wu 1991).

The external diameter of the needle is another factor that may be involved in the mechanisms of PDPH. Although all needles in a set can have the same internal diameter, which determines the amount of liquid that may be contained in the internal channel of the needle, they do not always have the same external size. The external diameter is determined by the cross-sectional area of the needle; larger diameters are expected to produce larger orifices in the dura mater, thereby allowing increased CSF leakage. Large gauges are represented by smaller numbers (e.g. 16-gauge, 17-gauge), and small gauges are represented by larger numbers (e.g. 29-gauge, 32-gauge) (Calthorpe 2004).

How the intervention might work

Studies that have compared needle internal diameters have found that needles of larger diameter produce larger holes in the dura mater, and this could lead to greater risk of post-dural puncture headache. However, evidence also suggests that the use of thinner needles increases the difficulty of the procedure and hence the number of bone punctures, causing needle tip deformities (Angle 2003). Some authors advocate the use of needles with cutting/traumatic tips based on the theory that these needles can cause larger lesions than are produced by pencil-point/atraumatic needles. Pencil-point needles were thought to penetrate and then separate dura mater fibres, resulting in less trauma and subsequently less loss of CSF and a lower incidence of PDPH (Arendt 2009). A large inflammatory reaction caused by larger lesions can lead to faster closing of the injury through rapid migration of the cells involved in scar formation. Microscopic analyses of corpses have revealed that injuries produced by pencil-point needles are more complex than those produced by cutting needles (Arendt 2009).

Why it is important to do this review

Lumbar puncture is part of everyday clinical practice and is associated with potential adverse effects (Evans 2009; Grande 2005). Prevention strategies should be preferred to treatment of adverse effects (Turnbull 2003). Morbidities associated with CSF loss, besides PDPH, include peripartum seizures, cranial subdural haematomas and subdural fluid collections (Arendt 2009; Janssens 2003). Even though most cases of PDPH are resolved within a few days, a significant number of patients experience at least one week of disability, and others require prolonged or recurrent hospitalizations (van Kooten 2008). Prevention strategies, such as the use of a prophylactic epidural blood patch, caffeine or different postures after lumbar puncture, have not proved effective for the prevention of PDPH in several Cochrane reviews (Arevalo-Rodriguez 2013; Basurto 2013; Boonmak 2010). It is advisable to assess additional prevention strategies regarding quality, safety and clinical benefits of related clinical trials, with the purpose of generating useful recommendations for clinical practice.


To assess the effects of needle tip design and diameter (gauge) on prevention of post-dural puncture headache (PDPH) in patients who have undergone dural puncture for diagnostic or therapeutic causes.


Criteria for considering studies for this review

Types of studies

We will include randomized controlled trials (RCTs) conducted in any clinical/research setting where dural puncture has been used.

Types of participants

We will include participants of all ages and both genders who have undergone lumbar puncture for medical reasons.

Types of interventions

Studies on participants undergoing lumbar puncture should assess one of the following interventions.

  • A needle tip design/bevel used for lumbar puncture (i.e. traumatic or atraumatic) versus another needle tip design/bevel.

  • A specified needle gauge (i.e. from 16-gauge to 32-gauge) versus another needle gauge.

  • Any combination of the above.

Types of outcome measures

Primary outcomes
  • Onset of PDPH, defined as each headache that worsens within 15 minutes of sitting or standing and is relieved within 15 minutes of lying down after a lumbar puncture. We will use the valid PDPH diagnostic criteria specified by the International Headache Society (Headache Classification Subcommittee IHS 2004).

  • Adverse events related to lumbar puncture: total adverse events and total serious adverse events. We will define an adverse event as “any untoward medical occurrence that may present during treatment with a pharmaceutical product but that does not necessarily have a causal relationship with this treatment."

Secondary outcomes
  • Severe PDPH, according to the definition used in each study, which could be based on specific features (e.g. duration of PDPH), the visual analogue scale (VAS) or other criteria such as the need for specialized treatments to manage the episode of headache (e.g. epidural blood patch).

  • Any headache subsequent to a lumbar puncture, to incorporate any possible data that had not been catalogued as PDPH, according to the definition used in each study.

Search methods for identification of studies

Electronic searches

We will search the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, current issue), PubMed, MEDLINE (1966 to date), EMBASE via Ovid SP (1982 to date) and LILACS (1982 to date). We will adopt the MEDLINE search strategy in searching the other databases. The search terms are a combination of thesaurus-based and free-text terms for both the intervention (lumbar puncture in neurological, anaesthesia or myelography settings) and the headache. See Appendix 2 for details of the MEDLINE search strategy. We will not impose a language restriction.

Searching other resources

We will search trial registries via the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal. In addition, we will search the reference lists from retrieved studies, information from clinical trial registration websites and conference proceedings.

Data collection and analysis

Selection of studies

Two review authors (IA-R and LM) will independently select studies for eligibility using Early Review Organizing Software (EROS) (Ciapponi 2011; Ciapponi 2011a; Glujovsky 2010). We will review titles and abstracts of all identified studies to determine whether they have fulfilled the inclusion criteria. We will assess the full texts of selected studies to confirm their relevance for inclusion. We will resolve any disagreement by consulting with a third review author (AC). We will not be blinded to the authors’ names and institutions, the journal of publication or the study results at any stage of the review.

Data extraction and management

Two review authors (JJA and LM) will independently use predesigned data forms to extract information from the original study reports about participants, methods of randomization, blinding, comparisons of interest, numbers of participants originally randomly assigned by arm, follow-up losses and outcomes (double data entry) (Appendix 3). We will record the reasons for exclusion of potential studies in the 'Characteristics of excluded studies' table. We will resolve any disagreement by discussion with a third review author (IA-R). We will enter extracted data into Review Manager 5 (RevMan 5.2) for the analyses.

Assessment of risk of bias in included studies

Two review authors (JJA and IA-R) will independently assess the risk of bias of included studies using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011). We will consider six domains (random sequence generation, allocation concealment, blinding of outcome assessment, incomplete outcome data, selective reporting and other bias). We will not consider blinding of participation and personnel because of the nature of the intervention (lumbar puncture). We will resolve any disagreement by discussion with a third review author (MRF).

Measures of treatment effect

We will present results as summary risk ratios (RRs) for incidence of PDPH, adverse events, severe PDPH and any headache along with 95% confidence intervals (CIs) and numbers needed to treat for an additional harmful outcome to damage (NNTH) as absolute measure of harm. We will calculate NNTH as the reciprocal of risk differences (RDs) (McQuay 1998).

Unit of analysis issues

We do not expect to encounter any unit of analysis issues, as we do not expect to find cross-over studies or cluster-randomized trials.

Dealing with missing data

We will retrieve levels of attrition if data are available. By performing sensitivity analyses, we will explore the impact of including trials with high levels of missing data in the overall assessment of treatment effect. For all outcomes, we will carry out analyses, as far as possible, on an intention-to-treat (ITT) basis (i.e. we will attempt to include in the analyses all participants randomly assigned to each group). We will assume that any participant lost to follow-up had experienced the outcome under consideration, but we will contact trialists for additional data on those lost to follow-up.

Assessment of heterogeneity

We will assess statistical heterogeneity of effect sizes by means of the I2 statistic. The I2 statistic describes the percentage of total variation across trials that is due to heterogeneity rather than to sampling error (Higgins 2003; Higgins 2011). If we identify at least moderate heterogeneity (i.e. I2 > 30%), we will explore it by performing prespecified subgroup analyses. If we identify substantial heterogeneity (I2 > 80%), we will not present the pooled result.

Assessment of reporting biases

We will assess reporting bias through careful attention to assessment of quality, particularly the quality of study methodology. A thorough search for unpublished studies performed by contacting known experts in the field will also assist in reducing the risk of publication bias. We will use funnel plot analysis to examine publication bias if at least 10 studies are included in the review.

Data synthesis

If the available data allow, we will summarize the findings using random-effects models with the DerSimonian-Laird method. We will carry out statistical analyses using Review Manager 5 (RevMan 5.2). If we identify substantial heterogeneity (I2 > 80%), we will not present a pooled result. If no statistical synthesis is possible, we will summarize the results qualitatively and will present them in tables.

Subgroup analysis and investigation of heterogeneity

For the primary outcomes, we will consider subgroup analyses for the following factors, as appropriate.

  • Participants undergoing dural puncture for anaesthesia only, diagnosis only or myelography only.

  • Pregnant women only.

  • Subgroup analysis for gender.

  • Subgroup analysis for age (younger than 18 years of age, older than 65 years of age and 18 to 65 years of age).

  • Subgroup analysis for posture during the lumbar puncture (e.g. lateral, sitting).

Sensitivity analysis

If sufficient trials are identified, we plan to conduct a sensitivity analysis to compare the results by using those RCTs classified as having a 'low risk of bias' (Higgins 2011) in three core domains: allocation concealment, incomplete outcome data and blinding of outcome assessment.

Summary of findings tables

We will use the principles of the GRADE system (Guyatt 2008) to assess the quality of the body of evidence associated with all main outcomes (onset of PDPH and adverse events), and we will construct a 'Summary of findings' (SoF) table using the GRADE profiler software. The GRADE approach appraises the quality of a body of evidence based on the extent to which one can be confident that an estimate of effect or association reflects the item being assessed. Evaluation of the quality of a body of evidence considers within-study risk of bias, directness of the evidence, heterogeneity of the data, precision of effect estimates and risk of publication bias (Balshem 2011; Guyatt 2011; Guyatt 2011a; Guyatt 2011b; Guyatt 2011c; Guyatt 2011d; Guyatt 2011e; Guyatt 2011f; Guyatt 2011g).


We would like to thank Mathew Zacharias (content editor), Marialena Trivella (statistical editor) and Andrew Moore, Stephen Halpern and Polpun Boonmak (peer reviewers) for their help and editorial advice during the preparation of this protocol for the systematic review. The review authors would also like to thank Arturo Marti-Carvajal for his support and assistance in the design of this review's search strategies and for giving feedback on this protocol.


Appendix 1. Glossary of terms

Term Definition Source
 Analgesia, epiduralRelief of pain without loss of consciousness through the introduction of an analgesic agent into the epidural space of the vertebral canal.
Analgesia, obstetricalElimination of pain, without loss of consciousness, during obstetrical labour; obstetrical delivery; or the postpartum period, usually through the administration of analgesics.
Blood patch, epidural Injection of autologous blood into the epidural space either as a prophylactic treatment immediately after an epidural puncture or for treatment of headache resulting from an epidural puncture.
Cerebrospinal fluid pressure Manometric pressure of the cerebrospinal fluid as measured by lumbar, cerebroventricular or cisternal puncture. Within the cranial cavity, it is called intracranial pressure.
Dura mater The outermost of the three meninges, a fibrous membrane of connective tissue that covers the brain and the spinal cord.
MyelographyX-ray visualization of the spinal cord after injection of contrast medium into the spinal arachnoid space.
NeedleSharp instruments used for puncturing or suturing.
Primary preventionSpecific practices for the prevention of disease or mental disorders in susceptible individuals or populations. These include health promotion, including mental health; protective procedures, such as communicable disease control; and monitoring and regulation of environmental pollutants.
Post-dural puncture headacheA secondary headache disorder attributed to low cerebrospinal fluid pressure caused by spinal puncture, usually after dural or lumbar puncture.
Spinal punctureTapping fluid from the subarachnoid space in the lumbar region, usually between the third and fourth lumbar vertebrae.

Appendix 2. MEDLINE (PubMed) search strategy

(Post-Dural Puncture Headache[Mesh] OR PDPH[tiab] OR PLPH[tiab] OR PPH[tiab] OR Post dural[tiab] OR Postdural[tiab] OR Headache[Mesh] OR Headach*[tiab] OR cephalea*[tiab] OR cephalalgi*[tiab]) AND (Anesthesia, Epidural[Mesh] OR Anesthesia, Spinal[Mesh] OR Injections, Spinal[Mesh] OR Myelography[Mesh] OR Spinal Puncture[Mesh] OR ((spinal[tiab] OR intraspinal[tiab] OR dural[tiab] OR intradural[tiab] OR epidural[tiab] OR lumbar*[tiab] OR thecal*[tiab] OR intrathecal[tiab] OR subarachnoid*[tiab] OR sub arachnoid*[tiab]) AND (Spinal Puncture[Mesh] OR puncture*[tiab] OR inject*[tiab] OR anesth*[tiab] OR anaesth*[tiab] OR needle*[tiab] OR Tap[tiab]))) AND (caliber[tiab] OR Needle Gauge*[tiab] OR Needle Tip*[tiab] OR Needle size*[tiab] OR Traumatic Tap*[tiab] OR Traumatic Needle*[tiab] OR Atraumatic Needle*[tiab] OR Pencil Point*[tiab] OR Diamond Tip*[tiab] OR Spinal Needle*[tiab] OR ((Quincke[tiab] OR Greene[tiab] OR Hingson[tiab] OR Lutz[tiab] OR Brace[tiab] OR Rovenstine[tiab] OR Lemmon[tiab] OR Whitacre[tiab] OR Atraucan[tiab] OR Sprotte[tiab] OR Cappe[tiab] OR Gertie Marx[tiab] OR Deutsch[tiab]) AND (Needle*[tiab])))

Appendix 3. Study eligibility screening and data extraction form

Needle Gauge and Tip designs for Preventing PDPHIntervention Cochrane Review

Study Selection, Quality Assessment & Data Extraction Form

First AuthorJournal/Conference proceedings, etcYear


1.      Study Eligibility

 RCT/CCTRelevant participantsRelevant interventionsRelevant outcomes*

aIssues related to selective reporting when authors may have taken measurements for particular outcomes but did not report these within the paper(s). Review authors should contact trialists for information on possible non-reported outcomes and reasons for exclusion from publication. Study should be listed in “Studies awaiting assessment” until clarified. If no clarification is received after three attempts, study should then be excluded.


Do not proceed if any of the above answers is “No”.

2.      References to Trial

Check other references identified in searches. If further references to this trial are identified, link the papers and list below. All references to a trial should be linked under one Study ID in RevMan.

AuthorJournal/Conference proceedings, etcYear

3.      Participant and Trial Characteristics

 Further details
Age, years (mean, median, range, etc.) 
Gender of participants 
Reason for puncture (dx, anaesthesia, radiology) 
Surgical procedure (obstetrical, orthopaedic, etc.) 
Type of anaesthesia used 
Trial design (parallel, etc.) 
Single centre/multi-centre 
Eligibility criteria 
Exclusion criteria 
Follow-up, years (mean, median, range, etc.) 
Time points reported in the study 

4.      Intervention Characteristics

 Further details
Needle tip 
Needle gauge 
Number of attempts 

5.      Number of Participants

 Enrolled participantsRandomly assigned participantsParticipants included in analysisLost to follow-upReasons
At beginning     
A Group     
B Group     
C Group     
D Group     

6.      Methodological Quality

 Low risk of biasUnclear risk of biasHigh risk of biasDetails
Random sequence generation    
Allocation concealment    
Blinding of participants and personnel    
Blinding of outcome assessment    
Selective reporting bias    
Incomplete outcome data    
Other bias    
Other (describe)    

7.      Results

 A Group (define) B Group (define) 
 # Participants with outcome# Participants analysed# Participants with outcome# Participants analysed

Severe PDPH


Any headache after spinal anaesthesia    
Other (define)     



Contributions of authors

Ingrid Arevalo-Rodriguez: (IA-R), Luis Muñoz (LM), Jimmy J Arevalo (JJA), Agustín Ciapponi (AC), Marta Roqué i Figul (MRF)

Conceiving the review: IA-R, LM

Designing the review: IA-R, LM, JJA, AC, MRF

Co-ordinating the review: IA-R

Undertaking manual searches: IA-R, LM, JJA

Screening search results: IA-R, LM, JJA

Organizing retrieval of papers: LM

Screening retrieved papers against inclusion criteria: IA-R, LM, JJA, AC, MRF

Appraising quality of papers: IA-R, LM, JJA, AC, MRF

Abstracting data from papers: LM, JJA

Writing to authors of papers for additional information: JJA

Providing additional data about papers: IA-R, AC

Obtaining and screening data on unpublished studies: IA-R, LM

Providing data management for the review: RM

Entering data into Review Manager (RevMan 5.2): IA-R, LM, JJA

Managing RevMan statistical data: MRF

Performing other statistical analyses not using RevMan: MRF

Ensuring double entry of data (data entered by person one: MRF; data entered by person two: IA-R)

Interpreting data: IA-R, LM, JJA, AC, MRF

Making statistical inferences: IA-R, LM, JJA, AC, MRF

Writing the review: IA-R, LM, JJA, AC, MRF

Providing guidance on the review: AC, MRF

Securing funding for the review: IA-R

Performing previous work that served as the foundation of the present study: IA-R, LM, AC, MRF

Serving as guarantor for the review (one author): IA-R

Taking responsibility for reading and checking the review before submission: IA-R, LM, JJA, AC, MRF

Declarations of interest

Ingrid Arevalo-Rodriguez: none known.

Luis Muñoz: none known.

Jimmy J Arevalo: none known.

Agustín Ciapponi: none known.

Marta Roqué i Figuls: none known.

Sources of support

Internal sources

  • Fundación Universitaria de Ciencias de la Salud, Bogotá D.C., Colombia.

  • Institute for Clinical Effectiveness and Health Policy IECS, Buenos Aires, Argentina.

  • Iberoamerican Cochrane Centre, Barcelona, Spain.

  • Universidad El Bosque, Bogotá, Colombia.

    Luis Muñoz is a Master of Science degree student at the Department of Clinical Epidemiology of El Bosque University, Bogotá, Colombia.

External sources

  • Agencia de Calidad del Sistema Nacional de Salud, Ministry of Health, Spain.