Frequency and importance of barotrauma in 100 patients with acute lung injury

Abstract

Objectives: To determine the occurrence rate of barotrauma in acute lung injury patients, whether barotrauma is an independent risk factor for mortality, and the role of barotrauma in the outcome of those patients who died.

Design: Prospective, cohort study.

Setting: Intensive care units at a university hospital.

Patients: Consecutive adult patients (n = 100) meeting the usual criteria for a diagnosis of acute lung injury requiring mechanical ventilation.

Measurements and main results: Barotrauma occurred in 13 (13%) of 100 patients. Mortality rates were not different in patients with (76%) and without (64%) barotrauma. Using univariate analysis, barotrauma was not associated with increased mortality (odds ratio 1.85; confidence interval 0.42 to 9.20; p = .53). However, when barotrauma was incorporated into a logistic regression model, along with other potential predictors of mortality, barotrauma was associated with increased mortality (odds ratio 6.15; confidence interval 1.11 to 33.9; p = .017). The presence of nonpulmonary organ dysfunction and sepsis was strongly associated with mortality. In the setting of barotrauma, the mortality rate was 100% if associated with two or more nonpulmonary organ dysfunctions compared with a mortality rate of 40% with one or no nonpulmonary organ failure. Barotrauma contributed directly to the cause of death in only one patient.

Conclusions: Barotrauma occurred in only 13% of patients with acute lung injury. Barotrauma was an independent marker of mortality when adjusted for other predictors of mortality. However, barotrauma directly contributed to < 2% of all deaths. We hypothesize that barotrauma is an indication of severity of acute lung injury rather than a major cause of increased mortality.