A Cochrane review [Abstract] 1 included two studies with a total of 47 subjects. One crossover trial including 18 participants showed 2 (95% CI 0.8 to 3.0) points more improvement after four weeks in an 11-point disability scale with plasma exchange (10 exchanges over four weeks) than with sham exchange. Rapid deterioration after plasma exchange occurred in eight of 12 who had improved. When these results were combined with another study with 29 participants treated in a parallel group design trial, there were 31 points (95% CI 16 to 45) more improvement in an impairment scale after plasma exchange (six exchanges over three weeks) than after sham exchange. There were significant improvements in both trials in the proximally evoked compound muscle action potential after three or four weeks. Non-randomised evidence indicates that plasma exchange induces potentially serious adverse events in 3% to 17% of procedures.
Comment: The quality of evidence is downgraded by limitations in study quality (inadequate follow up) and by imprecise results (limited study size for each comparison).
Primary/Secondary Keywords