Worldwide, more than 310 million surgical procedures are undertaken each year with an in-hospital mortality rate between 1.5% and 1.9% in developed countries. 1-3 High-risk patients represent a smaller proportion of the surgical population but accounts for more than 80% of the post-operative deaths. 2 A large database study reported a post-operative mortality of 0.42% in the standard surgical population and 12.3% in the high-risk population. 2 Post-operative complications seems to be the most important cause for poor surgical outcomes, admission to the intensive care unit (ICU) and shortand long-term post-operative mortality. 4-6 Patients undergoing major non-cardiac surgery make out a considerable proportion of the admissions to the ICU and utilise large amounts of resources. 7 While large population-based studies have characterised the high-risk surgical population in general, 2,3 few studies have specifically identified and characterised the high-risk surgical population admitted to the ICU following surgery. By exploring factors associated with morbidity and mortality on the short and long term for this patient group, it might be possible to identify clinically modifiable factors leading to better outcomes. The aim of this study was to characterize patients admitted to the ICU following non-cardiac surgery and identify risk factors associated with 30-days, 90-days and 1-year mortality after ICU admission. Background: The aim of this register-based cohort study was to characterize patients admitted to the intensive care unit (ICU) following non-cardiac surgery and identify risk factors associated with 30-days, 90-days and 1-year mortality after ICU admission. Methods: Patients aged 18+ years admitted to the intensive care unit within 30-days of non-cardiac surgery at four Capital Region hospitals in Denmark between January 2005 and December 2014 were included. Patients were identified through the Danish National Patient Register. The outcomes were 30-days, 90-days and 1-year mortality after ICU admission. Unadjusted and multivariate logistic regression analyses were performed to identify independent risk factors of mortality.
Results:The study included 3311 ICU patients. Gastrointestinal surgery accounted for 71.3%, orthopaedic surgery for 18.4% and urologic surgery for 10.2% of the population. For the total population, the median length of stay in hospital was 18 days (9-36, 25th-75th percentile) and 2 days (1-4, 25th-75th percentile) in the ICU. Thirtydays, 90-days and 1-year mortality were 37.8%, 44.5% and 51.2% respectively.Mortality within the ICU was 22.3% while the post-ICU in-hospital mortality was 19.4%. Higher age, comorbidity, delayed ICU admission, acute surgery, and gastrointestinal and orthopaedic surgery increased 30-days, 90-days and 1-year mortality.Conclusions: Short-and long-term mortality in non-cardiac surgical patients admitted to the ICU is very high, especially among the elderly comorbid patients undergoing acute surgery. Future research should focus on targeting clinically modifiable r...