In patients undergoing colonoscopy procedures (CPs), inadequate dosing of hypnotic drugs (HD) and opioid analgesics (OA) during intravenous sedoanalgesia (ISA) may lead to intraprocedural awareness with recall (IAwR), intraprocedural (IPP) and postprocedural pain (PPP), as well as postoperative nausea and vomiting (PONV). The aim of this study was to evaluate whether the titration of HD and OA based on the observance of changing values of state entropy (SE) and surgical pleth index (SPI) (adequacy of anesthesia—AoA), state entropy alone, or standard practice may reduce the number of adverse events. One hundred and fifty-eight patients were included in the final analysis. The rate of IAwR and IPP was statistically more frequent in patients from the C group in comparison with the AoA and SE groups (p < 0.01 and p < 0.05, respectively). In turn, the rate of PPP, PONV, and patients’ and operators’ satisfaction with ISA between groups was not statistically significant (p > 0.05). Changes in hemodynamic parameters, demand for HD, and OA were statistically significant, but of no clinical value. In patients undergoing CPs under ISA using propofol and FNT, as compared to standard practice, intraprocedural SE monitoring reduced the rate of IAwR and IPP, with no influence on the rate of PPP, PONV, or patients’ and endoscopists’ satisfaction. AoA guidance on propofol and FNT titration, as compared to SE monitoring only, did not reduce the occurrence of the aforementioned studied parameters, imposing an unnecessary extra cost.

Despite the possibility of postoperative pain occurrence, in some patients, vitreoretinal surgeries (VRSs) require performance of general anesthesia (GA). The administration of intraoperative intravenous rescue opioid analgesics (IROA) during GA constitutes a risk of perioperative adverse events. The Adequacy of Anesthesia (AoA) concept consists of an entropy electroencephalogram to guide the depth of GA and surgical pleth index (SPI) to optimize the titration of IROA. Preemptive analgesia (PA) using cyclooxygenase-3 (COX-3) inhibitors is added to GA to minimize the demand for IROA and reduce postoperative pain. The current analysis evaluated the advantage of PA using COX-3 inhibitors added to GA with AoA-guided administration of IROA on the rate of postoperative pain and hemodynamic stability in patients undergoing VRS. A total of 165 patients undergoing VRS were randomly allocated to receive either GA with AoA-guided IROA administration with intravenous paracetamol/metamizole or with preemptive paracetamol or metamizole. Preemptive paracetamol resulted in a reduction in the IROA requirement; both preemptive metamizole/paracetamol resulted in a reduced rate of postoperative pain as compared to metamizole alone. We recommend using intraoperative AOA-guided IROA administration during VRS to ensure hemodynamic stability alongside PA using both paracetamol/metamizole to reduce postoperative pain.

Background/Objectives: Some patients undergoing vitreoretinal surgery (VRS) require general anesthesia (GA), despite the possibility of developing intolerable postoperative pain perception (IPPP). Intraoperative rescue opioid analgesia (IROA) administration during GA poses a risk of perioperative nausea and vomiting (PONV), which may result in suprachoroidal hemorrhage with permanent visual impairment. Adequacy of Anesthesia (AoA) optimizes intraoperative IROA titration. Intravenous preemptive analgesia (IPA) with cyclooxygenase-3 (COX-3) inhibitors is added to GA to reduce the IROA dose. In this additional analysis, we assessed the impact of preemptive analgesia with COX-3 inhibitors, administered alongside GA with AoA-guided IROA, on the incidence of PONV, oculocardiac reflex (OCR), and oculoemetic reflex (OER) in patients undergoing VRS as secondary outcomes. Methods: A total of 165 patients scheduled for VRS were randomly assigned to receive AoA-guided GA combined with IPA at a single dose of 1 g of paracetamol (acetaminophen) or 2.5 g of metamizole or both. A total of nine patients were excluded due to technical problems with the intraoperative surgical pleth index (SPI) measurement, inability to report postoperative pain, and postoperative arousal resulting in a loss of follow-up in Stage 5. Results: Regardless of the group assignment, AoA guidance of GA resulted in PONV in 4%, OCR in 10%, and OER in 0% of the 153 analyzed patients undergoing VRS. No significant differences were observed between the groups regarding the type of IPA. PONV was observed in 2.11% (3/142) of patients with zero, one, or two risk factors of PONV, as compared to 27% (3/11) of patients with at least three PONV risk factors, assessed using the Apfel score. Conclusions: IPA with both paracetamol and metamizole did not demonstrate a benefit in reducing the analyzed adverse events compared with their single use in patients undergoing VRS under AoA guidance during GA. Surprisingly, PONV was hardly observed in patients with zero, one, or two PONV risk factors assessed by the Apfel score who underwent AoA-guided VRS during GA with IPA using one or two COX-3 inhibitors.

Background/Objectives: Intolerable postoperative pain perception (IPPP) may occur in patients undergoing vitreoretinal surgery (VRS), while general anesthesia (GA) is often preferred over regional techniques due to multiple contraindications. Intraoperative administration of intravenous rescue opioid analgesics (IROA) during GA increases the risk of perioperative adverse events; however, this requirement can be reduced through preventive analgesia. The Adequacy of Anesthesia (AoA) concept, based on entropy EEG and the Surgical Pleth Index (SPI), allows real-time titration of IROA to maintain optimal nociception/anti-nociception balance and create comparable intraoperative conditions across patients. This study aimed to identify risk factors for IPPP after VRS performed under AoA-guided GA combined with intravenous preventive analgesia using COX-3 inhibitors. Methods: A total of 165 patients scheduled for VRS were randomized to receive AoA-guided GA combined with intravenous preventive analgesia using either paracetamol plus metamizole, paracetamol alone, or metamizole alone. Results: Data from 153 patients were analyzed. Neither age, body mass index, smoking status, arterial hypertension, diabetes mellitus, intraoperative noxious maneuvers, demand for IROA, nor length of surgery correlated with the incidence of IPPP under AoA-guided GA. The combination of paracetamol and metamizole resulted in the lowest rate of IPPP among all groups. Conclusions: AoA-guided GA combined with COX-3 inhibitors appears to standardize intraoperative nociception/anti-nociception balance in patients undergoing VRS, effectively mitigating most known risk factors for IPPP, with female sex independently associated with its occurrence. We recommend the optimization of perioperative pharmacotherapy through individualized AoA-guided GA with intravenous COX-3 inhibitors to minimize IPPP incidence.