Anesthetic Regimens for Intraoperative Bulbocavernosus Reflex Monitoring in Pediatric Tethered Cord Surgery, Experiences from the University Hospital

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Sunisa Sangtongjaraskul
Lawan Tuchinda
Surunchana Lerdsirisopon
Vorrachai Sae-phua
Kornkamon Yuwapattanawong
Jiraphorn Amornfa


Background: Anesthetic management for intraoperative bulbocavernosus reflex (BCR) monitoring is challenging, particularly in pediatric patients. Objective: The aim of this study was to demonstrate anesthetic regimens for successful intraoperative BCR monitoring in pediatric patients. Methods: This retrospective descriptive study was done in pediatric patients who underwent untethered cord surgery with intraoperative BCR monitoring. The data collections were preoperative urinary and anal sphincter function, anesthetic technique, monitorable of BCR, significant change of BCR signal, duration of surgery and anesthesia. The outcomes collected were from postoperative urinary and anal sphincter dysfunction, length of ICU and hospital stay. Results: Seventeen patients obtained intraoperative BCR monitoring during untethered cord surgery for a 3-years period. Intraoperative BCR signal could be recorded in all patients during anesthetic maintenance with total intravenous anesthesia (TIVA) consisting of propofol and fentanyl infusion without muscle relaxant. Mean doses of propofol and fentanyl during BCR monitoring were 170.77±29.84 mcg/kg/min and 1.87±0.91 mcg/kg/hr, respectively. After finishing BCR monitoring, anesthesia was switched to inhalation anesthetics in 16 patients (94.12%). All patients were extubated in the operating room without postoperative ICU admission. Significant BCR signal changes were recorded in three patients. One of these patients had postoperative urinary dysfunction. All of them were discharged without complications. Conclusions: Intraoperative BCR was monitorable during anesthetic maintenance with TIVA using propofol and fentanyl without muscle relaxant in conjunction with maintenance of hemodynamic stability. This anesthetic regimen may contribute to a good neurological outcome as BCR signal was preserved and facilitate extubation.

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