A comparison of total body water analyses: Bioelectric impedance analysis versus the tritiated water method

Bioelectric impedance analysis (BIA) is used to measure the body compositio n and total body water of normal subjects. The purpose of this study was to determine if the hydration of patients with burns could be assessed by BIA . Assessments of total body water as determined by BIA and the tritiated wa ter method were prospectively compared. The 2 analyses were performed 48 ho urs after admission for 5 patients with acute burns to determine the correl ation of the 2 methods. The patients had a mean age of 36.4 +/- 14.7 years (range, 20-56 years), a mean burn size of 39.4% +/- 15.9% of the body surfa ce area (range, 23%-65%), and a mean full-thickness burn size of 27.7% of t he body surface area. The total body water was measured on admission and ag ain at 48 hours postburn. There is an excellent relationship between BIA an d tritiated-water-method determinations of the total body water of patients with severe burns (r = 0.958). This correlation suggests that BLA. provide s an accurate measure of total body water, and so it is a reliable means of monitoring fluid resuscitation in patients with burns.