[Mortality-associated factors in major surgery: retrospective analysis in a referral center]

There are very few studies that analyze surgical morbidity and mortality in the general population and the factors associated with those events.

To determine factors associated to mortality in surgical procedures performed in a tertiary referral center in Mexico City.

We retrospectively analyze surgical mortality in 4,157 consecutive surgical procedures performed in a one-year period from 1/1/2000 through 12/31/2000. Categorical variables were analyzed with the chi-square test and continuous variables with the t-Student test. Significance was defined as p < 0.05.

During the study period there were 76 postoperative deaths, representing a mortality rate of 1.82%. Mean patient's age in the entire cohort was 48.7 +/- 17.6 years and for the patients who died in the postoperative period 57.8 +/- 17.8 years (p < 0.05). Sixty-six percent of deaths were attributed to the primary or surgical disease. In 33.8% of postoperative deaths an adverse event was identified as responsible for the outcome. In 23% of cases there was a potentially preventable event, representing 0.3% of surgical procedures. Most patients (96.9%) had at least one comorbid condition and 61.5% had two or more. Almost 80% of surgical deaths occurred in patients with ASA score III of IV and albumin levels below 3.5 g/dL. Most common cause of death was sepsis, reported in 35% of patients who died in the postoperative period.

Surgical mortality in our series is low. In 0.3% of procedures it was detected a potentially preventable event. Postoperative deaths occurred in older patients with low albumin levels.