Long-term survival after surgical critical illness: the impact of prolonged preceding organ support therapy.

OBJECTIVE: To identify the prognostic importance of preceding invasive ventilation, renal replacement therapy, and catecholamine therapy for long-term survivors after surgical critical illness. SUMMARY BACKGROUND DATA: Nothing is known about the effect of preceding intensive care unit (ICU)-related therapies on long-term outcome. METHODS: We performed a retrospective analysis of prospectively collected data of an ICU patient cohort linked to a local database. Adult patients (n = 1462) admitted to a 12-bed ICU between 1993 and 2005, who had an ICU length of stay of more than 4 days, were followed up until the end of the second year after ICU admission. Hazard function was explored by Weibull modeling and likelihood ratio tests. Cox-type structured hazard regression models were used to analyze linear, nonlinear, or time-varying associations of therapeutic variables with 2-year survival time of a patient subgroup, which had survived the period of high hazard. RESULTS: Hazard rate declined exponentially up to day 195 after ICU admission, and became constant thereafter. A total of 808 patients reached this stable stage of their disease forming the study population. Of these patients, 648 (80.2%) were still alive at the end of the second year after ICU admission. Underlying diseases were major determinants for long-term outcome. Long-term mortality was significantly associated with the acute extent of physiological derangement during ICU stay (maximum Apache II score), but was independent from the duration of preceding invasive organ support. CONCLUSION: In surgical patients with a prolonged ICU length of stay, an exorbitant mortality exists for about half a year after ICU admission. Later on, life expectancy of surviving patients is largely determined by the underlying disease and, to a minor degree, by the acute extent of homeostatic disturbance during ICU stay. The duration of preceding invasive therapies does not limit long-term survival.