The possibilities of video-electroencephalographic monitoring in diagnostics of chronic post-anoxic myoclonus in children: a pilot study

Background. Most publications aimed at analyzing brain bioelectrical activity in post-anoxic conditions focus primarily on disturbances in the acute phase of post-anoxic encephalopathy (PAE). The dynamic changes in bioelectrogenesis mechanisms during subsequent disease progression are described in few publications reporting contradictory results. Motor phenomena recorded during PAE in children can be present simultaneously or alternate, creating difficulties in their interpretation and selection of pharmacotherapy. Therefore, a retrospective pilot study was needed to assess clinical significance of videoelectroencephalographic monitoring (VEEM) and the impact of its results on therapeutic strategy and prognosis for recovery in patients with chronic post-anoxic myoclonus (PAM).

Objective: Тo assess extent of VEEM sufficient to determine the level of myoclonus generation in children with PAE.

Material and methods. The retrospective study included 10 children with post-anoxic conditions of different genesis (freshwater drowning, mechanical asphyxia, cardiopulmonary resuscitation during septic shock) who underwent rehabilitation treatment at the Research Institute of Emergency Pediatric Surgery and Trauma – Dr. Roshal’s Clinic in the years 2020–2023. Nine of the examined subjects underwent VEEM according to a standardized protocol; 1 child received VEEM in another medical institution.

Results. Chronic PAM was present in 2 children examined. In one case, there was a myoclonus of different levels of generation combined with epileptiform seizures and generalized dystonia, in the other case – myoclonus recorded along with generalized dystonia. In both cases, the use of clonazepam improved PAM clinical manifestations.

Conclusion. Patients with history of PAM are required to receive an extended VEEM added with myographic channels for conducting differential diagnostics with motor phenomena, to clarify generation level for chronic postanoxic myoclonus, if any, and select pharmacotherapy strategy.

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