Hypotension in patients on chronic peritoneal dialysis: etiology, management, and outcome

We retrospectively evaluated the phenomenon of arterial hypotension in peritoneal dialysis (PD) in a large cohort of 633 PD patients from two centers (Toronto Western Hospital, Toronto, Canada, and Division of Nephrology, Democritus University of Thrace, Greece), thus extending our previously reported experience for an additional 6 years (1995-2000). Together, the units had 81 hypotensive patients (12.8%), whose mean age was 63.8 +/- 14.2 years and whose mean duration of peritoneal dialysis was 49.3 +/- 30 months. Based on the underlying pathophysiology, the hypotensive PD patients were divided into four groups: (A) hypovolemia, 32 patients (39.5%); (B) congestive heart failure (CHF), 15 patients (18.5%); (C) receiving antihypertensive medications, 11 patients (13.6%); and (D) "unknown" etiology, 23 patients (28.4%). All patients in the hypovolemic and antihypertensive groups responded well to treatment (volume expansion and discontinuation of antihypertensive medication, respectively), but in the CHF and "unknown" groups, only 40% improved with the appropriate intervention. Patients in the latter two groups showed the poorest prognosis, with an approximate death rate of 65%. The hypovolemic group had better outcomes, which might reflect prompt response to fluid replacement in that group. We conclude that, in PD patients, careful use of antihypertensive medication, the right evaluation of target weight (especially in patients with cardiac failure), and judicious use of hypertonic exchanges may prevent the severe complication of arterial hypotension.