Background: Catabolic illness is associated with fluid retention and extracellular space expansion. To determine the effect of human growth hormone (GH) on body water compartments, critically ill surgical patients were studied for a 2-week period during which they either continued to receive standard intensive care unit support, or in addition, received GH, 10 mg/day.
Methods: Body water compartments were measured at the beginning and end of the period by the indicator dilution technique with sodium bromide and heavy water used as the indicators of extracellular (ECW) and total body water (TBW), respectively; intracellular water (ICW) was calculated by subtraction.
Results: Neither group lost significant amounts of weight or TBW. A marked ECW expansion and disturbance of the ECW/TBW ratio occurred in the patients receiving standard care, which was associated with a dramatic reduction in ICW, a critical component of the body cell mass (BCM). In contrast, GH-treated patients maintained ECW and ICW, indicating a preservation of BCM, and their ECW/TBW ratio normalized.
Conclusions: GH administration prevents ECW retention and stabilizes or normalizes fluid distribution during critical illness. Taken together with its known anabolic effects under these conditions, the maintenance of ICW demonstrates that GH can be used to preserve BCM in complex surgical patients.