Intraoperative Neuromonitoring of Motor-Evoked Potentials in Infants Undergoing Surgery of the Spine and Spinal Cord.

Purpose: The aim of this single-center prospective cohort study is to record reliable transcranial motor-evoked potentials (TcMEPs) and to determine their thresholds under inhalational anesthesia in infants undergoing spine and spinal cord surgery.

Methods: A total of 15 infants (age <12 months) with mean (SD) months: 5.82 ± 3.45 were included. The entry criteria were that the child should be no older than 1 year of age and undergoing a surgical procedure at the conus-cauda region. The patients were monitored with motor-evoked potentials (TcMEPs) and bulbocavernosus reflex.

Results: Transcranial motor-evoked potentials were recorded in all the patients in both upper and lower extremities in one muscle at least. All patients were monitored with a mean TcMEP threshold of 488.46 ± 99.76 V (range 310-740 V). The lowest threshold of TcMEPs was used to record the musculus abductor pollicis brevis mean of 315.15 ± 126.95 V (range 140-690 V) and the highest for musculus sphincter ani mean of 444.17 ± 138.54 V (range 206-700 V).

Conclusions: Intraoperative neuromonitoring for spine and spinal cord procedures of the infant population requires higher TcMEP thresholds and train count. Most patients aged older than 6 months require significantly lower TcMEPs.