Ming-Tso Yan1, Chih-Jen Cheng2, Hsiu-Yuan Wang3, Chwei-Shiun Yang4, Sheng-Jeng Peng4, Shih-Hua Lin5. 1. Division of Nephrology, Department of Medicine, Cathay General Hospital, School of Medicine, Fu-Jen Catholic University, Taipei, Taiwan National Defense Medical Center, Taipei, Taiwan. 2. Division of Nephrology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan. 3. Department of Nutrition, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan. 4. Division of Nephrology, Department of Medicine, Cathay General Hospital, School of Medicine, Fu-Jen Catholic University, Taipei, Taiwan. 5. Division of Nephrology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan l521116@ndmctsgh.edu.tw.
Abstract
UNLABELLED: ♦ BACKGROUND: An approach to hyponatremia in uremic patients on peritoneal dialysis (PD) necessitates the assessment of intracellular fluid volume (ICV) and extracellular volume (ECV). The aim of the study was to evaluate the association of plasma sodium (Na(+)) concentration and body fluid composition and identify the causes of hyponatremia in non-diabetic PD patients. ♦ METHODS: Sixty non-diabetic uremic patients on PD were enrolled. Baseline body fluid composition, biochemistry, hand-grip test, peritoneal membrane characteristics, dialysis adequacy, Na(+) and water balance, and residual renal function (RRF) were measured. These parameters were reevaluated for those who developed hyponatremia, defined as serum Na(+) concentration < 132 mmol/L and a decline in serum Na(+) > 7 mmol/L, during monthly visits for 1 year. Body fluid composition was determined by multi-frequency bioelectrical impedance (BIA). ♦ RESULTS: There was no significant correlation between serum Na(+) concentrations and any other parameters except a negative correction with overnight ultrafiltration (UF) amount (p = 0.02). The ICV/ECV ratio was positively correlated with serum albumin (p < 0.005) and hand grip strength (p < 0.05). Over 1 year, 9 patients (M:F = 3:6, aged 35 - 77) with 4 different etiologies of hyponatremia were identified. Hyponatremic patients with a body weight (BW) loss had either an increased ICV/ECV ratio associated with primarily a negative Na(+) balance (n = 2) or a reduced ratio of ICV/ECV associated with malnutrition (n = 2). In contrast, hyponatremic patients with a BW gain had either a reduced ICV/ECV ratio associated with a rapid loss of RRF and a higher peritoneal permeability (n = 2) or a normal to increased ICV/ECV ratio associated with high water intake (n = 3). ♦ CONCLUSION: Besides BW change and ultrafiltration rate, the assessment of ICV/ECV ratio is valuable in identifying the etiologies of hyponatremia in PD and provides a guide for optimal therapy.
UNLABELLED: ♦ BACKGROUND: An approach to hyponatremia in uremicpatients on peritoneal dialysis (PD) necessitates the assessment of intracellular fluid volume (ICV) and extracellular volume (ECV). The aim of the study was to evaluate the association of plasma sodium (Na(+)) concentration and body fluid composition and identify the causes of hyponatremia in non-diabeticPDpatients. ♦ METHODS: Sixty non-diabetic uremicpatients on PD were enrolled. Baseline body fluid composition, biochemistry, hand-grip test, peritoneal membrane characteristics, dialysis adequacy, Na(+) and water balance, and residual renal function (RRF) were measured. These parameters were reevaluated for those who developed hyponatremia, defined as serum Na(+) concentration < 132 mmol/L and a decline in serum Na(+) > 7 mmol/L, during monthly visits for 1 year. Body fluid composition was determined by multi-frequency bioelectrical impedance (BIA). ♦ RESULTS: There was no significant correlation between serum Na(+) concentrations and any other parameters except a negative correction with overnight ultrafiltration (UF) amount (p = 0.02). The ICV/ECV ratio was positively correlated with serum albumin (p < 0.005) and hand grip strength (p < 0.05). Over 1 year, 9 patients (M:F = 3:6, aged 35 - 77) with 4 different etiologies of hyponatremia were identified. Hyponatremic patients with a body weight (BW) loss had either an increased ICV/ECV ratio associated with primarily a negative Na(+) balance (n = 2) or a reduced ratio of ICV/ECV associated with malnutrition (n = 2). In contrast, hyponatremic patients with a BW gain had either a reduced ICV/ECV ratio associated with a rapid loss of RRF and a higher peritoneal permeability (n = 2) or a normal to increased ICV/ECV ratio associated with high water intake (n = 3). ♦ CONCLUSION: Besides BW change and ultrafiltration rate, the assessment of ICV/ECV ratio is valuable in identifying the etiologies of hyponatremia in PD and provides a guide for optimal therapy.