Prognosis of critical surgical patients depending on the duration of stay in the ICU

OBJECTIVE: To analyze the epidemiological and prognostic differences between critical surgical patients admitted to intensive care unit (ICU) according to length of stay in the ICU. MATERIALS AND METHODS: Retrospective observational study on patients with surgical pathology admitted to ICU of a tertiary hospital, during 7 years, with a stay ≥ 5 days. The variables analyzed were age, sex, Acute Physiology and Chronic Health Evaluation II (APACHE II), duration of stay, hospital and ICU mortality, original service, reason for admission, geographical place of residence, and the use of invasive techniques such as mechanical ventilation (MV), tracheotomy, and techniques of continuous renal replacement (CRR). Two groups were defined; one with intermediate stay, the one that exceeds the average of our population (> 5 days) and another with long stay patients (> 14 days). Readmissions were excluded. Firstly, the analysis of differential characteristics of patients was performed, this was according to the duration of their stay using either a contrast equal averages when the variable contrast between the two groups was quantitative or the Chi-square test when the variable analyzed was qualitative. For both tests, the existence of significant differences between groups was considered when the significance level was less than 5%. And, secondly, a model forecast ICU survival of these patients, regardless of length of stay in ICU, using a binary logistic regression analysis was performed. RESULTS: Among the 540 patients analyzed, no significant differences were observed, depending on the length of stay in the ICU, except the need for invasive techniques such as MV or tracheotomy in those of longer stay (P = 0.000). However, ICU mortality was significantly higher for patients with intermediate stay (30 vs 17: 5%; P = 0.000), without observing differences in hospital mortality. ICU survival was influenced by age, APACHE II levels, admission to the ICU in a coma state, and the application of the three invasive techniques discussed. CONCLUSION: Surgical patients who survive in the ICU, regardless of the length of their stay in it, have the same odds of hospital survival. Found as predictors of mortality in ICU APACHE II, age, admission in a coma state, and application of invasive techniques.