Plasmapheresis before thymectomy in myasthenia gravis: routine versus selective protocols.

Objective: The value of thymectomy in management of myasthenia gravis (MG) is well recognized. Plasmapheresis (PMP) before thymectomy appears to improve the postoperative outcome. As PMP has its own complications, selective use of PMP preoperatively for patients at risk of post-thymectomy complications would improve the postoperative outcome, and decreases the PMP-related complications. The aim of this study is to evaluate the effectiveness and safety of routine versus selective use of PMP before thymectomy.
Material and Methods: We performed a retrospective analysis of two different protocols in two institutions comparing the routine (group I) versus selective use (group II) of prethymectomy PMP. The computerized database and the medical records of 164 patients diagnosed with MG who underwent thymectomy between 1998 and 2007, were reviewed.
Results: In group I, 74 patients were treated with PMP before thymectomy. In group II (90 patients), 35 patients were identified as high-risk and were treated with PMP before thymectomy, and in 55 patients, thymectomy was performed without preoperative PMP. There was significant difference in the recorded PMP-related complications between group I and group II; 25.7% (19 patients) versus 8.9% (8 patients), respectively. There was no difference between the two groups as regards the duration of postoperative mechanical ventilation, intensive care unit (ICU) stay and hospital stay.
Conclusion: This study demonstrated that selective use of PMP before thymectomy may reduce the incidence of PMP-related complications without affecting the overall outcome.