Microcirculation of the fingernail fold in CAPD patients: preliminary observations.

ABSTRACT

OBJECTIVE: To study changes in the peritoneal microcirculation during continuous ambulatory peritoneal dialysis (CAPD) by studying change in the microcirculation of the fingernails of CAPD patients. SETTING: A university department. DESIGN: A cross-sectional study of 10 nondiabetic patients on CAPD. INTERVENTION Hemorrheological tests of fingernail microcirculation using equipment built at our university. MAIN OUTCOME MEASURES: Microcirculation was characterized by estimation of capillary density, red blood cell (RBC) column diameter, torque index, and RBC flow velocity semiquantitatively using videocapillaroscopy at the fingernail fold and plasma viscosimetry. Findings were correlated with treatment duration, peritoneal clearance, state of capillary morphology and hemodynamics, and lipid and fibrinogen levels. RESULTS: Treatment duration was significantly correlated (p < or = 0.05) with low-density lipoprotein (LDL) (r = 0.776) and clearances of urea (r = -0.583), uric acid (r = -0.666), and potassium (r = -0.764). Changes in capillary morphology were correlated to clearances of urea (r = 0.643) and uric acid (r = 0.701). The fibrinogen concentration increases plasma viscosity (r = 0.799) and deteriorates the capillary state (r = -0.706). In addition, plasma viscosity correlates to cholesterol (r = 0.620, NS) and LDL (r = 0.781), but not to high-density lipoprotein and triglycerides. CONCLUSION: CAPD treatment results in lipid abnormalities and high fibrinogen levels that may cause microvascular damage and poor perfusion. These interactions may explain the deterioration of peritoneal transport in some CAPD patients.