Pneumatic compression devices during hemodialysis: a randomized crossover trial.

BACKGROUND Maintenance of central blood volume (CBV) is essential for hemodynamic stability during hemodialysis (HD), though preservation of CBV is poorly understood. Pneumatic compression devices (PCDs) during HD may help maintain CBV. METHODS We performed a randomized, crossover trial to determine the effect of PCDs on CBV during HD. Patients underwent two consecutive mid-week HD sessions, randomized to begin the first session either with or without PCDs [stratified by intradialytic hypotension (IDH)-prone status]. The primary outcome was change in CBV during HD. The secondary outcomes were change in other hemodynamic and volume status parameters. RESULTS Fifty-one patients (median age 65 years, 75% male, 22% IDH-prone) were randomized; forty-six completed the study. During HD, the median change in CBV for PCD and control sessions was -0.08 versus -0.05 L (P = 0.62). There was no difference in the change in cardiac output (CO) (-0.63 versus -0.49 L/min, P = 0.78) or systemic vascular resistance (SVR) (+1.30 versus +1.55 mmHg/L/min, P = 0.67) for PCDs versus control. Based on the bioimpedance measurements, patients were not volume overloaded pre-dialysis. There was a greater reduction in total body water (TBW) (-2.6 versus -2.3 L, P = 0.05) and intracellular fluid (ICF) volume (-1.3 versus -1.1 L, P = 0.03), and no difference in change in the extracellular fluid (ECF) volume (1.3 versus 1.2 L, P = 0.09) with PCDs versus control. Similar results were observed in IDH-prone patients. CONCLUSIONS Compared with standard of care, PCDs have no effect on intradialytic hemodynamic parameters, including CBV, although they may allow greater capacity for fluid removal. Further studies are required to better understand physiological and hemodynamic changes in patients during HD.