Purpose: To describe the factors related to outcome in patients admitted to the intensive care unit (ICU) after major surgery at a national level (in Austria).
Methods: Analysis of a prospectively collected database of ICU admissions over an 11-year period. Factors associated with mortality and how this changed with time were explored using logistic multilevel modelling.
Results: A total of 88,504 surgical patients had a mean ICU length of stay of 6.5 days and total hospital stay of 31.3 days. They had an ICU mortality of 7.6% and a hospital mortality of 11.8%. Factors associated with hospital mortality included age (odds ratio (OR) 1.42 per 10 years of age), urgency of operation (2.02 for emergency when compared to elective), SAPS II score (OR 1.09), reason for admission being a medical cause and the specific nature of the surgery itself: thoracic (OR 1.81), cardiovascular (OR 1.25), trauma (OR 1.22) or gastrointestinal surgery (OR 1.71). In addition patients who had pre-existing chronic renal (OR 1.40), respiratory (OR 1.20) or cardiac failure (OR 1.29), cirrhosis (OR 2.50), alcoholism (OR 1.42), acute kidney injury (OR 1.88) and/or non-metastatic cancer (OR 1.20) were associated with higher hospital mortality than patients without this co-morbidity. There was a reduction in the OR for death over the whole 11-year period. This improved outcome remained valid even after adjusting for the identified risk factors for mortality (OR per year 0.96).
Conclusions: This study has shown the high level of demand for critical care for this patient group and an improving rate of survival.