Background and objectives: Anesthesia maintenance agents affect the incidence of postoperative shivering (PS) after general anesthesia. This study compared the effects of remimazolam with sevoflurane on PS in patients undergoing laparoscopic gynecologic surgery under general anesthesia. Materials and methods: Seventy-four patients were allocated into one of two groups. In anesthesia maintenance, group S received sevoflurane and remifentanil, and group R received remimazolam and remifentanil. Results: The incidence and severity of postoperative shivering, mean arterial pressure (MAP), heart rate (HR), core body temperature, and the association of PS with hypothermia, MAP, or HR in the post-anesthesia care unit (PACU) were measured. Group R had significantly lower rates of perioperative hypothermia (58.8 vs. 27.8%, p = 0.009) and postoperative shivering (41.2 vs. 19.4%, p = 0.047). The severity of PS was also lower in group R than in group S (p = 0.034). Core body temperature was significantly higher in group R than in group S from 10 min after induction (p = 0.047) to the PACU (p = 0.009). MAP and HR were significantly higher in group R than in group S from 20 min after induction (p = 0.047) to the PACU (p = 0.009). In group S, the correlation between the severity of PS and the incidence of hypothermia (φc = 0.414, p = 0.121) was moderate but not significant. In group R, the correlation between PS severity and hypothermia (φc = 0.418, p = 0.043) was moderate and significant. Conclusions: Remimazolam showed better results than sevoflurane in anesthesia maintenance regarding hypothermia and PS.

Background and Objectives: The effects of midazolam, a benzodiazepine, on pain perception are complex on both spinal and supraspinal levels. It is not yet known whether remimazolam clinically attenuates or worsens pain. The present study investigated the effect of intraoperative remimazolam on opioid-induced hyperalgesia (OIH) in patients undergoing general anesthesia. Materials and Methods: The patients were randomized into three groups: group RHR (6 mg/kg/h initial dose followed by 1 mg/kg/h remimazolam and 0.3 μg /kg/min remifentanil), group DHR (desflurane and 0.3 μg /kg/min remifentanil) or group DLR (desflurane and 0.05 µg/kg /min remifentanil). The primary outcome was a mechanical hyperalgesia threshold, while secondary outcomes included an area of hyperalgesia and clinically relevant pain outcomes. Results: Group RHR had a higher mechanical hyperalgesia threshold, a smaller hyperalgesia postoperative area at 24 h, a longer time to first rescue analgesia (p = 0.04), lower cumulative PCA volume containing morphine postoperatively consumed for 24 h (p < 0.01), and lower pain intensity for 12 h than group DHR (p < 0.001). However, there was no significant difference in OIH between groups RHR and DLR. Conclusions: Group RHR, which received remimazolam, attenuated OIH, including mechanically evoked pain and some clinically relevant pain outcomes caused by a high dose of remifentanil. Further research is essential to determine how clinically meaningful and important the small differences observed between the two groups are.

Background and Objectives: This study aimed to compare the effects of patient-preferred music delivered intraoperatively versus postoperatively on Emergence Delirium (ED) incidence, severity, and duration, while identifying predictors, to evaluate non-pharmacologic interventions for enhanced anesthetic management. Materials and Methods: In a prospective, single-blind, randomized controlled trial, 360 patients aged ≥ 65 years undergoing elective surgery under general anesthesia were randomized to intraoperative music, postoperative music, or control groups. Participants selected genres played via headphones. Primary outcome was ED incidence (Richmond Agitation–Sedation Scale [RASS] score ≥ +1 within 60 min after extubation); secondary outcomes included severity, duration, visual analogue scale pain scores, satisfaction, and adverse events. Results: Intraoperative music reduced ED incidence (13.8% vs. 28.7% in controls, p < 0.001) and severity (mean RASS 1.3 vs. 1.8, p < 0.01). Postoperative music shortened duration (15.2 vs. 22.5 min, p < 0.01) and pain (mean visual analogue scale 3.0 vs. 4.2, p < 0.01). Both improved satisfaction (p < 0.001). Higher preoperative State–Trait Anxiety Inventory scores predicted ED (odds ratio [OR] 1.06, p = 0.01), with music protective (OR 0.45–0.62). Conclusions: Intraoperative music effectively prevents ED, and postoperative music improves recovery. Integrating patient-preferred music and screening for anxiety may enhance peri-anesthesia care in elderly patients.

Background and Objectives: Postoperative delirium (POD) is a common complication in elderly patients undergoing major surgery, associated with systemic inflammation and potentially influenced by anesthetic techniques. This study investigated whether remimazolam-based total intravenous anesthesia (R-TIVA) reduces the level of systemic inflammatory biomarkers and the incidence of POD more compared to inhalational anesthesia (IA) or balanced anesthesia (BA) in patients aged ≥ 65 years undergoing major non-neurosurgical, non-cardiac surgery. Materials and Methods: This retrospective cohort study analyzed the medical records of 340 patients categorized by anesthesia type: R-TIVA (n = 111), IA (n = 117), or BA (n = 112). Propensity score matching (PSM) created POD (n = 104) and No POD (n = 106) cohorts. Systemic inflammatory biomarkers—the systemic immune–inflammation index (SII), the neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio (PLR), and C-reactive protein (CRP)—were measured pre- and postoperatively. POD was identified by clinical symptoms or the postoperative use of antipsychotics/sedatives. Results: The incidence of POD did not significantly differ among the R-TIVA, IA, and BA groups. However, the postoperative SII, NLR, PLR, and CRP levels were significantly lower in the R-TIVA group compared to those in the IA group (p < 0.05). Both the preoperative (r_pb = 0.72, p < 0.01) and postoperative (r_pb = 0.58, p < 0.01) NLRs were strongly correlated with POD. Higher NLR values predicted the incidence of POD, with odds ratios of 1.71 for preoperative and 1.32 for postoperative measurements. Conclusions: While R-TIVA did not significantly reduce the incidence of POD compared to that of IA or BA, it was associated with reduced levels of postoperative inflammatory biomarkers. The preoperative and postoperative NLRs emerged as strong predictors of POD, suggesting their potential utility in guiding prophylactic strategies for older surgical patients. These findings underscore the interplay between anesthesia type, systemic inflammation, and delirium risk.

Background and Objectives: The analgesia/nociception index (ANI) potentially monitors nociceptive status during anesthesia, but its link to preoperative pain sensitivity is unclear. We investigated the relationship between pre-anesthetic ANI scores and propofol injection pain (PIP) in patients receiving remifentanil. Materials and Methods: This study included 124 male patients aged 19–60 undergoing general anesthesia (ASA class I or II). Patients were randomized to group R (n = 62, remifentanil 4 ng/mL) or group C (n = 62, saline). The primary outcome was the association between PIP and ANI. Secondary outcomes included the incidence and severity of PIP or rocuronium-induced withdrawal movement (RIWM) and their association with ANI. Results: PIP and RIWM incidence and severity were lower in group R than in group C. A weak negative correlation between PIP and ANI at pre-induction (r_pb = −0.21, p = 0.02, r_pb = −0.37, p < 0.01) and a moderate negative correlation during propofol injection (r_pb = −0.48, p = 0.02) were observed. A significant negative correlation was found between RIWM and ANI during rocuronium injection (τb = −0.61, p < 0.01). AUC, cut-off value, specificity, and sensitivity in ANI at pre-induction for predicting PIP were 0.67 (p = 0.02), 59, 76%, and 55%, respectively. AUC, cut-off value, specificity, and sensitivity in ANI during propofol injection for PIP were 0.77 (p < 0.01), 65, 81%, and 67%, respectively. Conclusions: ANI scores demonstrated significant differences between groups, suggesting potential predictive value for PIP despite the low pre-induction AUC value. This study highlights the potential of using ANI scores to predict and manage PIP in patients receiving remifentanil.