BLOOD PRESSURE CONTROL IN HEMODIALYSIS PATIENTS: CONTRIBUTION OF BIO -IMPEDANCEMETRY

Abstract

Objective: Arterial hypertension is common in hemodialysis patients of which physiopathology is multifactorial. Moreover, it is associated with an increased risk of cardiovascular disease and a higher mortality. Fluid overload is the main contributing factor. Few studies have assessed the interpretation of parameters obtained through bioelectrical impedance (BIA) for the management of these patients. Design and method: we conducted a cross-sectional study at the Hemodialysis Center of Hedi Chaker in Sfax, Tunisia. Multifrequency bioimpedance analysis (BIA) was used to assess the hydration status which is performed at the end of the dialysis session. Results: Our study included 29 patients, with a mean age of 46.8 years (21-78 years) and an average dialysis vintage of 92.4 months. Male predominance was noted with a sex ratio of 1.06. Forty-eight percent of patients were hypertensive. Twenty-three percent of patients were on triple antihypertensive therapy, 13.3% were on dual therapy, and 16.7% were on monotherapy. Hypertension was essential in 64.2% of cases, renin-dependent in 14.2%, and volume-dependent in 21.6% of cases. Twenty-point seven percent (20.7%) of patients were in fluid overload, with an average overhydration of 0.9 liters. The impedance measurements were consistent with the data from cardiac ultrasound. The diameter of the inferior vena cava was significantly correlated with overload (p=0.01). However, there is no correlation between pulmonary arterial hypertension (HTAP) and the hyperhydration (p=0.4). Conclusions: Bio-impedancemetry is a valuable and simple tool at the patient's bedside for the dry weight estimation and the proper management of volume status in chronic hemodialysis patients, and consequently, blood pressure control.