The attributable mortality and length of intensive care unit stay of clinically important gastrointestinal bleeding in critically ill patients

Objective To estimate the mortality and length of stay in the intensive car e unit (ICU) attributable to clinically important gastrointestinal bleeding in mechanically ventilated critically ill patients. Design Three strategies were used to estimate the mortality attributable to bleeding in two multicentre databases. The first method matched patients w ho bled with those who did not (matched cohort), using duration of ICU stay prior to the bleed, each of six domains of the Multiple Organ Dysfunction Score (MODS) measured 3 days prior to the bleed, APACHE II score, age, admi tting diagnosis, and duration of mechanical ventilation. The second approac h employed Cox proportional hazards regression to match bleeding and non-bl eeding patients (model-based matched cohort). The third method, instead of matching, derived estimates based on regression modelling using the entire population (regression method). Three parallel analyses were conducted for the length of ICU stay attributable to clinically important bleeding. Setting Sixteen Canadian university-affiliated ICUs. Patients A total of 1666 critically ill patients receiving mechanical venti lation for at least 48 hours. Measurements We prospectively collected data on patient demographics, APACH E II score, admitting diagnosis, daily MODS, clinically important bleeding, length of ICU stay, and mortality. Independent adjudicators determined the occurrence of clinically important gastrointestinal bleeding, defined as o vert bleeding in association with haemodynamic compromise or blood transfus ion. Results Of 1666 patients, 59 developed clinically important gastrointestina l bleeding. The mean APACHE II score was 22.9 +/- 8.6 among bleeding patien ts and 23.3 +/- 7.7 among non-bleeding patients. The risk of death was incr eased in patients with bleeding using all three analytic approaches (matche d cohort method: relative risk [RR] = 2.9, 95% confidence interval (CI) = 1 .6-5.5; model-based matched cohort method: RR = 1.8, 95% CI = 1.1-2.9; and the regression method: RR = 4.1, 95% CI = 2.6-6.5). However, this was not s ignificant for the adjusted regression method (RR = 1.0, 95% CI = 0.6-1.7). The median length of ICU stay attributable to clinically important bleedin g for these three methods, respectively, was 3.8 days (95% CI = -0.01 to 7. 6 days), 6.7 days (95% CI = 2.7-10.7 days), and 7.9 days (95% CI = 1.4-14.4 days). Conclusions Clinically important upper gastrointestinal bleeding has an imp ortant attributable morbidity and mortality, associated with a RR of death of 1-4 and an excess length of ICU stay of approximately 4-8 days.