Orthostatic hypotension in kidney pancreas transplant patients and its relation to preexisting autonomic neuropathy.

Objectives: Orthostatic hypotension is a known complication of pancreas transplant. This retrospective study of 25 kidney-pancreas transplant patients at our center was done to determine the incidence and course of postoperative orthostatic hypotension.

Materials And Methods: A chart review was done for all patients who received a kidney-pancreas transplant between January 1997 and December 2005. Patients with orthostatic hypotension after surgery were selected and compared with patients without orthostatic hypotension for preexisting autonomic and peripheral neuropathy status. The kidney-pancreas transplant group was then compared with a group of diabetic kidney-only transplant recipients to assess the contribution of the renal transplant in this process.

Results: Seven kidney-pancreas transplant patients (28%) developed orthostatic hypotension after the transplant. It occurred with much higher frequency in kidney-pancreas transplant patients than it did in kidney transplant patients (P = .002). The onset of orthostatic hypotension was between 8 and 20 days after transplant. Six patients required midodrine for symptomatic relief. Orthostasis resolved completely within 3 weeks to 9 months in all but 1 patient. There was no correlation between postoperative orthostasis and preoperative history of orthostatic hypotension, gastroparesis, or peripheral neuropathy. Orthostasis was related to posttransplant polyuria in only 1 patient. In the remaining patients, orthostasis seemed to be related to the presence of the pancreas transplant. The exact pathogenesis of orthostasis is unclear but may be related to hyperinsulinemia after transplant or neuropeptides involved in the regenerative process.

Conclusions: Orthostatic hypotension is common after kidney-pancreas transplant. It is unrelated to preexisting autonomic neuropathy or posttransplant polyuria in most patients. This complication requires further study.