The impact of erector spinae plane (ESP) block on neurophysiological monitoring in patients undergoing scoliosis repair

Background
Preventive analgesia is designed to ensure perioperative pain control. The erector spinae plane (ESP) block may abolish the neuroendocrine stress response and augments controlled hypotensive anesthesia. But to what extent does it interfere with spinal cord function.
Methods
The patient’s population is divided into Group N (control) and Group E (ESP Group). A baseline for the amplitude and/or latency of either somatosensory evoked potentials (SSEPs) or motor evoked potentials (MEPs) were collected (30 min after induction of anesthesia and after full reverse of muscle relaxant before performing ESP block) in group E, the change from the baseline was recorded as a percent decrease. The total dose of anesthetics, the adjuvant analgesics and the postoperative complications were recorded.
Results
The change in the latency and the amplitude of SSEPs and MEPs among the two groups showed a non-significant change from the baseline. The intra-operative fentanyl consumption was significantly lower in group E than in C. The mean was 21.5 ± 25 vs 178.2 ± 46 mg respectively. The total doses of propofol and dexmedetomidine were lower in group E than in C. 18% of the patients in group E requested a rescue analgesic at a median of 70 (65) min postoperatively vs 55% of those in group C that requested analgesics earlier at a median 16(6) min.
Conclusion
The ESP block can be safely used without interfering with the monitoring of the somatosensory and MEPs during complex spinal surgery.