SEARCH

SEARCH BY CITATION

Long-term outcomes following extended intensive care stay after cardiac surgery

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

I. Moideen, M. Columb, N. O’Keeffe and M. Forrest

Manchester Royal Infirmary and Wythenshawe Hospital, Manchester, UK

While significant data exist regarding outcomes following cardiac surgery, there is a paucity of data regarding outcomes in the subgroup of patients who require prolonged intensive care following cardiac surgery. ACTA is currently benchmarking cardiac intensive care. We examined outcomes on our ICU to identify 2-year survival, trends over time and potential risk factors for adverse outcome.

Methods

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

Using our cardiac surgery database, we identified patients who had stayed in ICU for ≥ 5 days between April 1997 and March 2008. Data were collected for age, procedure, length of stay, pre-operative ejection fraction and Euroscore. All survival data were described in completed months. Survival data were analysed using 2-year mortality for all years. Trends in mortality were analysed using chi-squared and Armitage tests for trends in proportions. Trends in Euroscore and age over the same period were analysed using non-parametric linear regression. Multiple logistic regression was used to identify independent predictors of mortality in the first 2 years following discharge alive from ICU. Significance was defined at p < 0.05 (two-sided).

Results

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

The number of patients staying ≥ 5 days on ICU after surgery was 648, representing 5.6% of the total cases. Mortality (2-year) in these patients, averaged over the period, was 42% (range 32–70%). Data for each year are shown in Fig. 1. There was a significant reduction in mortality over the period studied. Omitting the outlying year (1997) reduces this trend, but there remains a small decrease with a reduced variance in mortality. There was a significant increase in Euroscore over the same time period (p = 0.03) and a small but non-significant rise in age. Age (OR 1.45, 95% CI 1.15–1.75 per year), fair (OR 1.95, 1.10–3.44) or poor left ventricular ejection fraction (OR 4.43, 2.03–9.63) and length of ICU stay (OR 1.03, 1.01–1.04 per day) were all identified as significant independent predictors of 2-year mortality.

image

Figure 1.  Two-year mortality 1997–2008.

Download figure to PowerPoint

Discussion

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

Patients who required extended ICU care following cardiac surgery had a 2-year mortality of 42%. Age, left ventricular function and length of stay were all predictors of death. While these data cannot be used to direct clinical decision making for individual patients, they may be of use in benchmarking cardiac ICU care and estimating the probability of 2-year survival.

Pre-operative anaemia has been shown to be a risk factor for adverse outcomes after cardiac surgery [1, 2]. In 2007, we started to treat anaemia in patients referred for elective surgery. Early success in a few patients led to the gradual creation of a new service, provided by the anaesthetists, the impact of which has not been evaluated.

Methods

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

No ethical approval was required to analyse the data. Pre-operative anaemia was defined by WHO criteria as Hb < 13 g.dl−1 in men or < 12 g.dl−1 in women. Ferritin < 100 ng.l−1 or transferrin saturation < 20% was a prerequisite for treatment. Intravenous iron (Cosmofer® (Vitaline Pharma, Oxon, UK) or Ferinject® (Syner-Med, Surrey, UK)) and darbepoetin (Amgen, CA, USA) were given to patients at least 1 week before surgery. All cardiac surgery patients who received intravenous iron were identified by the hospital pharmacy. We extracted the subset of patients who were treated pre-operatively before elective surgery. This list was checked against data collected prospectively by the surgeons. Difference in Hb was calculated from the last Hb value measured before surgery and Hb before treatment.

Results

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

Between April 2007 and April 2010, a total of 1874 patients underwent cardiac surgery at the unit; 1397 (74%) of these were elective procedures. Two hundred and twenty-one (15%) of these elective patients were anaemic on admission for surgery, including 32 patients who had been treated for anaemia, but remained anaemic. Although the majority of patients referred to us fulfilled criteria for treatment, no data were collected for patients who were investigated further but not treated. In total, 75 elective patients (49 men and 27 women) were treated for a median (IQR) of 47.5 (25.3–66.3) days before surgery. Mean (SD) difference in Hb was 1.5 (1.1) g.dl−1. An increase in Hb of at least 0.5 g.dl−1 was seen in 80% of the patients, resulting in 43 patients (57%) who were no longer anaemic by the time they were admitted for surgery.

Discussion

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

Treatment of pre-operative anaemia using intravenous iron and darbepoetin was effective. A significant rise in Hb was seen overall and the condition was completely corrected in 57% of patients. However, two thirds of elective patients who were anaemic at the time of surgery were either unsuitable or not referred for treatment. To develop the service further, we need to find out why these patients were missed. Potentially, pre-operative anaemia could be avoided in more than half of elective patients.

Anaemia is increasingly common in the ageing population in the UK. The Health Service Circular 2007/001 (Better Blood Transfusion – Safe and Appropriate Use of Blood) recommends that anaemia should be diagnosed and corrected in advance of surgery. The definition of anaemia varies widely.

Results

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

Of 2688 patients studied (Table 1), the overall transfusion rate was 38.1% (1025/2688). Cost comparison for blood transfusion alone was £417 722 in anaemic patients (n = 1717), compared with £276 528 in non-anaemic patients (n = 971). The overall mortality rate was 2.2% (58/2688).

Table 1.   Comparison of anaemic and non-anaemic patients. Values are number (proportion) or mean.
 Total patientsPatients transfusedDeathsICU stay; daysTransfusion cost; £
Anaemic1717 (63.9%)384 (22.4%)21 (1.2%)1.94155.81
Non-anaemic971 (36.1%)641 (66.0%)37 (3.8%)2.86430.20
p value < 0.001< 0.001< 0.01< 0.001

Discussion

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

Pre-operative anaemia is a common condition in cardiac surgical patients, and is associated with higher red cell transfusion requirement, mortality rate, financial cost and longer postoperative ICU stay. The aetiology of anaemia in this setting remains unclear. Correcting pre-operative anaemia by treating the underlying causes may lead to a reduction in transfusion and improved outcome. This is yet to be tested prospectively, including a detailed analysis of the cost implications of such a measure.

A national study was undertaken; the aim was to establish whether current thoracic training is achieving the proficiency and confidence required in this speciality as per the curriculum [1].

Results

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

Seven hundred and ninety-one trainees from 20 UK deaneries responded; 633 (80%) undertook thoracic training as part of a cardiothoracic module; 399 (50%) were ‘signed off’ as competent and were included for subsequent analysis of competence and confidence (Fig. 2).

image

Figure 2.  Trainee confidence to perform thoracic anaesthesia skills. DLT, double lumen tube; BB, bronchial blocker; OLV, one-lung ventilation.

Download figure to PowerPoint

Seventy-six per cent of respondents scored themselves as confident (≥ 8/10) to proceed with classic anaesthetic emergencies compared with 40% for common thoracic cases; 46% of all trainees, and 30% of final year trainees, did not feel proficient to CCT level [1] despite having been ‘signed off’ for their module of training. Eighty-six per cent felt that a skills and simulation course would be useful to their thoracics training.

Discussion

  1. Top of page
  2. Long-term outcomes following extended intensive care stay after cardiac surgery
  3. Methods
  4. Results
  5. Discussion
  6. Treatment of pre-operative anaemia in patients undergoing cardiac surgery
  7. Methods
  8. Results
  9. Discussion
  10. References
  11. The prevalence and significance of pre-operative anaemia in elective cardiac surgical patients
  12. Methods
  13. Results
  14. Discussion
  15. Reference
  16. Thoracic anaesthesia training: the national ‘One Lung’ survey
  17. Methods
  18. Results
  19. Discussion
  20. References

This is the largest survey of trainees’ perception of current thoracic training. Cardiac/thoracic anaesthesia is one of the six ‘key units of training’ yet only a slim majority of anaesthetic trainees feel proficient at the level required for CCT. Training opportunities are limited by European Working Time Regulations, centralisation of tertiary services and service commitments. Simulation/manikin-based learning is a well-validated training adjunct [2]. We have designed and implemented nationally the thoracic anaesthesia training course ‘One Lung’ to try to address these issues.