Features of intraoperative neurophysiological monitoring during neurosurgical interventions in pregnant women: A clinical case and literature review

Introduction. Conducting intraoperative neurophysiological monitoring in pregnant patients presents a complex challenge, as planning its protocol and choosing the anesthetic management requires consideration not only of the impact on the stability and reproducibility of the recorded neurophysiological parameters but also the specifi cs of pregnancy physiology and potential risks to the fetus. However, information regarding its use and safety is extremely scarce and requires further study.
Case description. This article presents a clinical case of a 29-year-old patient who underwent surgery at the Neurosurgery Department of the Irkutsk Order of the Badge of Honor Regional Clinical Hospital at 29 weeks of gestation for an intradural tumor of the cauda equina nerve roots (ependymoma G2) at the L2–L3 vertebral level, with the use of intraoperative neurophysiological monitoring (IONM). Anesthetic management included combined endotracheal anesthesia in conjunction with an erector spinae plane block. The IONM protocol included recording of somatosensory evoked potentials from the lower extremities, free-run electromyography, and stimulated electromyography. During direct stimulation of the nerve root intimately adhered to the tumor, M-responses were obtained from the left lower leg muscles; the nerve root was preserved, and the tumor was mobilized and removed en bloc. No new neurological defi cit was observed in the early postoperative period; at the time of discharge, the condition of both the mother and the fetus was satisfactory.
Conclusion. Thus, the use of IONM in pregnant patients with neurosurgical pathology improves the neurological outcome of the disease and is safe for both the mother and the fetus.

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