Effect of topical or peribulbar analgesia on the incidence of oculocardiac reflex, postoperative pain and postoperative nausea and vomiting following vitreoretinal surgery under surgical pleth index-guided general anaesthesia.

Abstract

Background: Despite of the risk of postoperative intolerable pain perception (PIPP), vitreoretinal surgery (VRS) requires general anaesthesia (GA) in selected patients. Intraoperative use of opioid analgesics (OA) during GA carries the risk of postoperative nausea and vomiting (PONV). The surgical pleth index (SPI) optimises the intraoperative titration of OA. Regional anaesthesia techniques are combined with GA to minimize the intraoperative use of OA. We evaluated the benefit of preventive analgesia techniques combined with GA using SPI-guided fentanyl (FNT) administration on the incidence of PONV, oculocardiac reflex (OCR) and PIPP in patients undergoing VRS. Methods: One hundred and five patients undergoing VRS were randomly allocated to receive either GA with SPI-guided fentanyl (FNT) administration alone (GA group) or with preventive topical 2% proparacaine (topical anaesthesia (TA) group) or preoperative peribulbar block (PBB) using 0.5% bupivacaine with 2% lidocaine (PBB group). Fifteen patients were excluded due to problems with postoperative SPI measurement. Results: Preventive PBB resulted in intraoperative reduction in FNT requirement, with no influence on perioperative outcomes. Intraoperative SPI-guided FNT administration during GA resulted in OCR in 7.78%, PONV in 10% and PIPP in 13.5% of patients undergoing VRS. Intraoperative SPI-guided FNT administration blunted the perioperative effect of preventive PBB and TA in terms of the presence of PONV, OCR and PIPP.Conclusions: The utility of SPI-guided FNT administration during GA eliminated benefits of preventive analgesia with PBB and TA following VRS. We recommend using intraoperative SPI-guided FNT administration during GA to reduce the presence of OCR, PONV and PIPP following VRS. Trial registration: The trial was approved and registered by The Ethical Committee of Medical University of Silesia on 29th of September 2015, as well as the project was registered in the Clinical Trial Registry (SilesianMUKOAiIT2, NCT02973581)Key words: vitreoretineal surgery, general anaesthesia, peribulbar block, topical anaesthesia, surgical pleth index.