Neuraxial analgesia is not associated with an increased risk of post-partum relapses in MS

Background:

Obstetrical analgesia remains a matter of controversy because of the fear of neurotoxicity of local anesthetics on demyelinated fibers or their potential relationship with subsequent relapses.

Objective:

To assess the impact of neuraxial analgesia on the risk of relapse during the first 3 months post-partum, with a focus on women who experienced relapses during pregnancy.

Methods:

We analyzed data of women followed-up prospectively during their pregnancies and at least 3 months post-partum, collected in the Pregnancy in Multiple Sclerosis (PRIMS) and Prevention of Post-Partum Relapses with Progestin and Estradiol in Multiple Sclerosis (POPARTMUS) studies between 1992–1995 and 2005–2012, respectively. The association of neuraxial analgesia with the occurrence of a post-partum relapse was estimated by logistic regression analysis.

Results:

A total of 389 women were included, 215 from PRIMS and 174 from POPARTMUS. In total, 156 women (40%) had neuraxial analgesia. Overall, 24% experienced a relapse during pregnancy and 25% in the 3 months post-partum. Women with a pregnancy relapse were more likely to have a post-partum relapse (odds ratio (OR) = 1.83, p = 0.02), independently of the use of neuraxial analgesia. There was no association between neuraxial analgesia and post-partum relapse (OR = 1.08, p = 0.78).

Conclusion:

Neuraxial analgesia was not associated with an increased risk of post-partum relapses, whatever multiple sclerosis (MS) activity during pregnancy.

[Significance of abnormally high somatosensory evoked potentials (SEV)]

Data found in the literature and our own observations prompted us to consider the possibility that abnormally enlarged Somatosensory Evoked Potentials (SEPs) may have a diagnostic and physiopathological significance, particularly in a group of diseases which include common clinical features of encephalopathy with stimuli-sensitive myoclonus and epilepsy, whatever their etiology may be (degenerative or storage disease, metabolic, toxic or post-hypoxic encephalopathy...). We discuss the amplitude, morphology, diagnostic and therapeutic contribution of these 'giant' SEPs and pathogenic assumptions with reference to 'cortical reflex myoclonus'. Studies of back-averaged encephalogram, SEPs and long-loop reflexes allow some illustration of a functional hyperreactivity of the sensori-motor cortex, but no conclusive demonstration of its origin.