Regional variation in critical care provision and outcome after high-risk surgery

Purpose Evidence of variation in mortality after surgery may indicate preventable postoperative death. We sought to determine if regional differences in outcome were present in surgical patients admitted to critical care in the UK. Methods We extracted data on admission characteristics, case mix and outcome of all patients admitted to UK critical care units following surgery for the calendar year of 2009. We also used publicly held data on regional population, volume of surgery and bed provision. Multilevel regression analysis was used to adjust for the effects of case mix and regional critical care bed provision on acute hospital mortality. Results A total of 16,147 patients admitted to critical care following surgery were included in this analysis. Median odds ratio (MOR) was used to describe regional-level variance in acute hospital mortality. Significant variation was identified (MOR 1.14; 95 % CI 1.07, 1.28) and persisted following adjustment for case mix (MOR 1.10; 95 % CI 1.04, 1.25) and regional critical care bed provision (MOR 1.09; 95 % CI 1.04, 1.24). Critical care bed utilisation (surgical critical care admissions per 100,000 surgical procedures) seemed to better explain this observation (MOR 1.03; 95 % CI 1.00, 29.26) and was associated with statistically significant reduction in mortality (OR 0.91; 95 % CI 0.85, 0.97; p = 0.01). Conclusion Significant regional variation in hospital mortality for patients admitted to critical care following surgery was observed. Critical care bed utilisation seemed to better explain this observation and was associated with improved outcome.