PROLONGED OVEREXPANSION OF EXTRACELLULAR WATER IN ELDERLY PATIENTS WITH SEPSIS

Objective: To compare the sequential changes in extracellular water (E CW) expansion in elderly patients receiving intensive care for severe sepsis with those in a similar group of younger patients. Design: Ince ption cohort study. Setting: Critical Care Unit and University Departm ent of Surgery in a single tertiary care center. Patients: A consecuti ve series of 14 patients older than 60 years (n = 8) or younger than 4 0 years (n = 6) with severe sepsis who completed sequential measuremen ts of body composition during a 21-day period. Main Outcome Measure: S equential measurements of body composition including ECW by bromide di lution, total body water by tritium dilution, and fat-free body mass b y dual-energy x-ray absorptiometry were performed during 21 days after resuscitation. Excess ECW was estimated from the difference between m easured ECW and ECW predicted from fat-free body mass corrected to nor mal hydration. Results: On the first study day, ECW was overexpanded b y 9.05 +/- 1.87 L (mean +/- SEM) and 10.33 +/- 1.79 L in the young and elderly groups, respectively (P = .66). Whereas the young group excre ted most of this excess ECW by day 5 (P = .008), the elderly group rem ained overexpanded until day 10 before mobilization of ECW occurred (P = .003). The changes over time of ECW excess were significantly diffe rent (P = .02 for group X time interaction). The elderly group require d more prolonged inotropic (P = .009) and ventilatory (P = .004) suppo rt and remained in intensive care longer (P= .008) than the young grou p. Conclusions: The period of ECW expansion is more prolonged in elder ly patients with sepsis and contributes to a poorer outcome from criti cal illness. This new finding is of fundamental importance to the trea tment of elderly patients recovering from severe sepsis.