Non-invasive method for preventing intradialytic hypotension: A pilot study.

Intradialytic hypotension (IDH) is a life-threatening condition. We evaluated the feasibility of blood volume monitoring (BVM) and blood temperature monitoring (BTM) in preventing IDH in patients prone to the same. Fourteen hemodynamically unstable end-stage renal disease patients who were prone to IDH and unable to achieve dry weight were given BVM treatment twice weekly for two weeks. Forty patients who were not on BVM treatment served as controls. Patients were anemic, had low serum albumin (3.4 ± 0.43 g/dL) and fluid overload and were edematous. Of the 40 patients in the control group, 18 patients experienced IDH and dialysis had to be terminated. The incidence of IDH was 5% in the control group. In the BVM group, the total volume of fluid removed during hemodialysis was between 2.0 and 4.5 L (mean 3.2 L). By the end of dialysis, the hemo-concentration increased by 34.8%. With use of BVM and BTM, the blood pressure did not drop below 120/80 mm Hg, the dialysis sessions were uneventful and none of the patients suffered symptoms of hypotension. There was a difference of 3 kg between weight achieved and dry weight of the patient, although there was a 14.2% reduction in extracellular water (ECW), 14.5% in plasma fluid and 14.5% decrease in interstitial fluid. Blood volume significantly correlated with post-dialysis intracellular water (ICW) (r = 0.722, P = 0.008) and ECW/ICW ratio (r = 0.698, P = 0.012). There was a significant correlation between systolic blood pressure and ECW (r = 0.615, P = 0.033). Diastolic blood pressure significantly correlated with post-dialysis ECW (r = 0.690, P = 0.008), plasma fluid post-dialysis (r = 0.632, P = 0.027) and interstitial fluid (r = 0.604, P = 0.038). The ECW/ICW ratio was high (1.13 ± 0.48; control 0.74), implying overhydration and expanded extracellular fluid. BVM should be included in the dialysis protocol where patient compliance to maintenance hemodialysis is poor and patients are constantly in volume overload.