Highlights from

AAN 2019

American Academy of Neurology annual meeting

Philadelphia, USA 4-10 May 2019

Preoperative intravenous Ig to prevent myasthenic crisis in myasthenia gravis unjustified

Results of a prospective, randomised, double-blind, single-centre study seem to suggest that preoperative intravenous immunoglobulin (IVIg) to prevent myasthenic crisis in myasthenia gravis (MG) patients is unjustified under certain conditions. The preoperative functional status has to be good, and the responsible multidisciplinary unit has to be experienced in MG care.

Study results were presented by Dr Josep Gamez (Vall d’Hebron University Hospital Barcelona, Spain). He said myasthenic crisis is a serious and potentially life-threatening complication of MG that will occur in 15–20% of patients during their lifetime. This is the first prospective study ever conducted to evaluate IVIg as protection against postoperative myasthenic crisis in MG patients undergoing surgical procedures. The 47 participants were randomised to treatment with IVIg at 0.4 mg/kg/day preoperatively for 5 consecutive days (n=25), or saline solution under the same conditions (n=22). The two groups were matched in age, functional status, and MGFA class. The mean forced vital capacity (FVC) was 84.4%, the mean QMG sum score 6.3. Five patients in each arm had a history of myasthenic crisis; 16 patients underwent thymectomy.

Primary outcome was the occurrence of myasthenic crisis. Only 1 patient, who received placebo, presented with myasthenic crisis requiring non-invasive ventilation (but not reintubation) for 6 days. There were no differences between groups in the univariate analysis, nor risk factors for myasthenic crisis in the multivariate analysis. “In our series, no myasthenic crisis may be expected if preoperative QMG score <8 and preoperative FVC >70%”, Dr Gamez observed. He concluded: “IVIg need not be administered to patients before thymectomy and other surgical procedures if there is a good preoperative functional status; and in multidisciplinary MG/NMD units with neurologists, anaesthetists, and surgeons experienced in MG patient care.”

Gamez J, et al. AAN 2019, Plen02.003.

The content and interpretation of these conference highlights are the views and comments of the speakers/authors.