Intraoperative Monitoring of Anorectal Sphincter Complex during a Surgery in Children with Anorectal Malformations

Summary

Diagnostic perioperative electromyostimulation of the sphincter complex muscles with bipolar Pena stimulator is used for anorectal reconstruction in children with congenital anorectal malformations (ARM). The objective of this study was to develop an accurate technique for perioperative measurement of electromyographic parameters in children with ARM and, consequently, to determine the most suitable method of general anesthesia. A KeyPoint EMG v3.22 (Medtronic) was used. The tissue of the sphincter complex was stimulated with a bipolar electrode and a DCN 25 thin concentric needle electrode was used for recording. Intensity of the stimulation was 14 mA administered over 0.2 ms. The method was used in 17 patients repeatedly during a surgery for anorectal malformation. The examinations were performed at various stages of anesthesia: after induction and during epidural blockade or after administration of a muscle relaxant. The results were compared to scarce data in the lite­rature and confirmed their validity. Through evaluation of the results, the described method was found to be sufficiently accurate. A combination of inhalation anesthesia, opioids and epidural block, with an exclusion of non-depolarizing muscle relaxants, was determined to be the most useful method of anesthesia.

Key words:
perioperative electromyostimulation – anorectal malformation – anorectal sphincter complex – caudal epidural anesthesia