Plasmapheresis-related hypotension

Hypotension is an uncommon complication of procedures involving extracorpor eal circulation, including plasmapheresis. From November 1993 to March 1999 , we treated 139 patients who underwent a total of 1,137 sessions of double filtration plasmapheresis (DFP). Hypotension was defined as a systolic blo od pressure (BP) < 80 mm Hg or any decrease of systolic BP with systemic re actions. A total of 17 (1.5%) episodes of hypotension were documented in 15 patients during the study period. Hypotensive episodes occurred in 2.3% of patients with inflammatory neuropathy, 1.2% of patients with myasthenia gr avis, and 1.2% of patients with all other medical diseases. Involvement of the autonomic nerve system (ANS) and a low baseline BP were associated with the occurrence of hypotension. Eight (47%) of 17 episodes were symptomatic and 2 were complicated with seizure. Patients with symptomatic hypotension had a higher level of systolic BP prior to DFP and a larger drop of systol ic BP and pulse rate during hypotensive attacks compared to asymptomatic pa tients. Most hypotensive episodes were resolved briefly after intravenous i nfusion of saline within 30 min. Eight (47%) of the hypotensive episodes oc curred during the first session of DFP treatment. Twelve (71%) of 17 episod es occurred during the last half period of treatment; 6 of them were noted during the terminating stage of DFP. In conclusion, in this series plasmaph eresis-related hypotension occurred in 1.5% of DFP sessions and had a highe r prevalence in patients with ANS instability and low BP. Extra caution in monitoring Bf during DFP therapy is warranted in these vulnerable patients, especially during the termination phase of the first DFP session.