[Causes and mechanisms of death in abdominal surgery]

To describe the causes and mechanisms of postoperative mortality in abdominal surgery.

The primary endpoints were mechanism and cause of death within 30 days after surgery. Mortality-associated factors were examined in Cox proportional hazards model with mixed effects.

Analysis included 550 patients (335 (60.9%) men and 215 (39.1%) women) who underwent abdominal surgery in level II hospitals; 59 (10.7%) out of 550 patients died within 30 days after surgery. Mean age of patients was 53 years. In respiratory diseases, acute respiratory failure associated with damage to lung parenchyma should be noted. Among cardiovascular diseases, the following mechanisms should be distinguished: distributive (e.g., intestinal ischemia, anastomotic insufficiency, sepsis), hypovolemic (blood loss), obstructive (PE), cardiogenic (acute heart failure, arrhythmia, myocardial infarction). The most common causes of death were gastrointestinal perforations (7 patients), upper gastrointestinal bleeding (2 patients), PE (3 patients), and intestinal gangrene (2 patients). Among 59 patients, 6 (10.2%) died within 24 hours, 21 (35.6%) - within the period from 24 hours to 7 days, 12 (20.3%) - within 8-14 days, 20 (33.9%) - later than 14 days after surgery. Forty-seven (79.7%) out of 59 patients died in hospital and 12 (20.3%) patients died outside the hospital.

Circulatory failure accounts for majority of deaths after abdominal surgery. Differences in time to death highlight the risk of death throughout perioperative period and after discharge. We propose to stratify the causes of death to primary and secondary ones (due to the main disease independent on postoperative outcomes and due to postoperative complication).