ABSTRACT
PURPOSE: Determination of accurate body fluid is essential for treating hypertension in end stage renal disease patients undergoing dialysis. However, the determination of dry body weight based on clinical assessment has low sensitivity and specificity. This study was done in order to examine the usefulness of bioimpedance analysis in determining the volume of CAPD patients. METHODS: Twenty-four hours ambulatory blood pressure and plasma concentrations of atrial natriuretic peptide (ANP) were measured and peritoneal equilibration test (PET) were obtained from 32 stable CAPD patients. Patients were divided into three groups; patients with normal blood pressure (group A, 11 people), and patients who have hypertension but controlled (under 130/80mmHg) with anti-hypertension medication (group B, 9 people), patients who have high blood pressure (over 130/80 mmHg) with 2 more anti-hypertension medication (group C, 12 people). We measured normalized extracellular fluid (nECF), extracelluar fluid/intracellular fluid ratio (ECF/ICF) and extracellular fluid/total body water (ECF/ TBW) of each group by using bioimpedance analysis (BIA) and compared the results of each group. We also compared the values of nECF, ECF/ICF, ECF/TBW indices from patients with those from normal renal function people. RESULT: Thirteen men and nineteen women participated in this test. Their mean age was 53+/-12 years and mean duration of CAPD was 49+/-38 months. Among three groups, plasma ANP level in group C (53.1+/-13.6 pg/mL) was significantly higher than the level in group A (10.3+/-7.2 pg/mL) and B (13.7+/-8.1 pg/mL) (p<0.05). The values of nECF, ECF/ICF, ECF/TBW that measured by BIA in group C was significant higher than the values in group A and B, but the values in group A and B were not significant different. The values of nECF, ECF/ICF, ECF/TBW from patients with normal kidney function were not different from those of group A and B, but the values were significantly lower than the values in group C (p<0.05). Plasma ANP level was correlated with nECF, ECF/ICF, ECF/TBW (p<0.05) value. Plasma ANP and nECF, ECF/ICF, ECF/TBW was not influenced different PET result. CONCLUSION: BIA is considered as a useful standard to predict the volume status in CAPD patients. In the future, prospective studies are demanded for clinical application.