Intravenous Immunoglobulin to prevent Myasthenic Crisis after Thymectomy and other Surgical Procedures can be omitted: A Randomized, Controlled, Double-Blind Trial. (Plen02.003)

Objective: To test the hypothesis that preoperative intravenous immunoglobulin (IVIg) is effective for preventing myasthenic crisis (MC) in myasthenia gravis (MG) patients scheduled for surgery under general anesthesia, including thymectomy.

Background: Myasthenic crisis (MC) is a serious and potentially life-threatening complication of myasthenia gravis (MG) occurring in 15–20% of patients during their lifetime. Precipitating factors for MC include respiratory infection, aspiration, sepsis, exposure to drugs increasing myasthenic weakness, pregnancy, and surgical procedures, particularly thymectomy.

Design/Methods: A prospective, randomized, double-blind, single-center study (EudraCT 2012-001544-21) was conducted over four years. The treatment group received IVIg at 0.4 mg/kg/day preoperatively for 5 consecutive days and the placebo group received saline solution under the same conditions. The two groups were age-matched, with similar functional status, and MGFA class. MC was the primary outcome. Postoperative intubation, longer recovery room stays, postoperative complications, and longer hospitalization times were secondary outcomes.

Results: 47 patients were randomized, 25 to the IVIg group and 22 to placebo. There were 19 men and 28 women, with a mean age of 58.6 years, mean BMI of 27.8 kg/m2, and mean anti-AChR antibodies of 12.9 nmol/L. The mean forced vital capacity (FVC) was 84.4%. The mean QMG sum score was 6.3. Ten patients (5 in each arm) had a history of MC. 16 patients underwent thymectomy. Only one placebo patient presented with MC requiring noninvasive ventilation (but no reintubation) for 6 days. Neither differences between groups in the univariate analysis nor risk factors for MC in the multivariate analysis were found.

Conclusions: Preoperative IVIg to prevent MC appears to be unjustified in well-controlled MG patients.

Disclosure: Dr. Gamez has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Minoryx, Italfarmaco, Octapharma AG, and CSL Behring. Dr. Salvado has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Italfarmaco and CSL Behring.. Dr. Carmona has nothing to disclose. Dr. de Nadal has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Baxter, Edwards, Ferrer, and Reig Jofre. Dr. Ruiz has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Grünenthal. Dr. Martinez has nothing to disclose. Dr. Deu has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Medtronic. Dr. Suñe has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Spanish Hospital Pharmacy Society and Biotest.. Dr. Romero has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Spanish Lung Cancer Association, Roche and Medtronic. Dr. Jáuregui has nothing to disclose. Dr. Pérez has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Medtronic, Ethicon and Baxter.