Emergence agitation (EA), also referred to as emergence delirium, can have clinically significant consequences. The mechanism of EA remains unclear. The proposed risk factors of EA include age, male sex, type of surgery, emergency operation, use of inhalational anesthetics with low blood–gas partition coefficients, long duration of surgery, anticholinergics, premedication with benzodiazepines, voiding urgency, postoperative pain, and the presence of invasive devices. If preoperative or intraoperative objective monitoring could predict the occurrence of agitation during emergence, this would help to reduce its adverse consequences. Several tools are available for assessing EA.However, there are no standardized clinical research practice guidelines and its incidence varies considerably with the assessment tool or definition used. Total intravenous anesthesia, propofol, μ-opioid agonists, N-methyl-D-aspartate receptor antagonists, nefopam, α2-adrenoreceptor agonists, regional analgesia, multimodal analgesia, parent-present induction, and preoperative education for surgery may help in preventing of EA. However, it is difficult to identify patients at high risk and apply preventive measures in various clinical situations.The risk factors and outcomes of preventive strategies vary with the methodologies of studies and patients assessed.This review discusses important outcomes of research on EA and directions for future research.

Background: Catheter-related bladder discomfort (CRBD) is common in patients with a urinary catheter and is a risk factor for emergence agitation (EA). The mainstay of CRBD management is anticholinergics. Dexamethasone inhibits acetylcholine release. This study aimed to evaluate the effects of dexamethasone on postoperative CRBD and EA.Methods: In this prospective study, 90 patients undergoing urological surgery requiring urinary catheterization were allocated randomly to one of two groups (each n = 45). Before induction of anesthesia, the dexamethasone group received 10 mg (2 ml) of dexamethasone intravenously, while the control group received 2 ml of saline in the same manner. The incidence and severity of CRBD were assessed 0, 1, 2, and 6 h after the patient arrived in the post-anesthesia care unit (PACU) as the primary outcomes. The incidence and severity of EA were also compared during emergence and recovery from anesthesia as secondary outcomes.Results: The incidences of CRBD in the control group and dexamethasone group at 0, 1, 2, and 6 h postoperatively were 28.9% and 15.6%, 55.6% and 55.6%, 57.8% and 46.7%, and 53.3% and 51.1%, respectively. The incidence and severity of CRBD assessed at 0, 1, 2, and 6 h postoperatively did not show intergroup differences. The incidence and severity of EA in the operating room and PACU also showed no difference between the groups.Conclusions: Dexamethasone (10 mg) administered before induction of anesthesia did not further reduce the incidence or severity of CRBD or EA in patients undergoing urological surgery.

Geriatric patients are susceptible to respiratory and hemodynamic adverse events during endotracheal intubation and extubation due to anatomic and physiological changes with aging. Supraglottic airway devices (SADs) provide reduced airway morbidity and increased hemodynamic stability in adults. However, studies that have compared the clinical performance of SADs in geriatric patients are limited. Therefore, we evaluated the clinical performance of airway management with i-gel® and laryngeal mask airway Supreme (LMA SupremeTM) in geriatric patients. The subjects were American Society of Anesthesiologists physical status classification I-III geriatric (65-85 years) patients who underwent elective surgery with general anesthesia and were randomly allocated into the i-gel® group and the LMA SupremeTM group. We compared the time for successful insertion on a first attempt as a primary outcome, and the secondary outcomes were success rate, ease of insertion, maneuver for successful ventilation, oropharyngeal leak pressure, gastric insufflation, fiberoptic view grades, ventilator problems, and adverse events. Insertion time was significantly shorter for the i-gel® than the LMA SupremeTM (21.4 ± 6.8 vs. 29.3 ± 9.9 s; P = 0.011). The i-gel® was also easier to insert than the LMA SupremeTM (P = 0.014). Gastric insufflation was less frequent with the i-gel® than the LMA SupremeTM (0% vs. 31.3%; P = 0.013). Other measurements were comparable between groups. Both devices can be safely applied to geriatric patients with similar success rates and oropharyngeal leak pressures. However, inserting the i-gel® was faster and easier compared to the LMA SupremeTM in geriatric patients.

Background: Sugammadex allows rapid recovery from rocuronium-induced neuromuscular blockade. Succinylcholine is often used for brief surgeries but is associated with myalgia, headache, histamine release, and increased lactate levels. Thus, we hypothesized that succinylcholine may affect emergence agitation (EA) and compared the effects of succinylcholine and rocuronium-sugammadex on EA in patients undergoing closed reduction of a nasal bone fracture under general anesthesia.Methods: Forty-two patients were prospectively enrolled and allocated randomly to the succinylcholine group (group SC) or the rocuronium-sugammadex group (group RS; eachn = 21). Neuromuscular block and its reversal were achieved with succinylcholine and normal saline in group SC, whereas rocuronium and sugammadex were administered in group RS. After surgery, the incidence of EA as a primary outcome, the incidence of dangerous EA, and duration of EA as secondary outcomes were compared.Results: The incidence of EA was higher in group SC than in group RS (90.5% vs. 47.6%, respectively; relative risk [RR] 4.3; 95% confidence interval [CI] 1.2 to 15.7;P = .006). The incidence of dangerous EA increased in group SC compared to group RS (33.3% vs. 4.8%, respectively; RR 2.1; 95% CI 1.3 to 3.4;P = .045). The duration of agitation was longer in group SC than in group RS [106.5 (65.1) vs. 40.4 (26.0) sec; mean difference 66.1 s; 95% CI 31.0 to 101.1; effect size 1.3;P = .001).Conclusion: Succinylcholine increases the incidence, severity, and duration of EA compared to rocuronium-sugammadex in patients undergoing closed reduction of a nasal bone fracture.Trial registration: CRiS Registration numberKCT0002673. Initial registration date was 31 January 2018 (Retrospectively registered).

Background: Remifentanil and sufentanil are potent short-acting synthetic opioid analgesics. The administration of remifentanil has been associated with the incidence of opioid-induced hyperalgesia. Opioid-induced hyperalgesia may be alleviated when opioids, such as morphine, are switched to sufentanil. Therefore, this retrospective observational study aimed to compare the effects of remifentanil and sufentanil on postoperative pain in patients undergoing robotic gynecological surgery. Methods: We retrospectively analyzed the electronic medical records of patients who underwent elective robotic gynecological surgery between January 2016 and February 2021. The patients were classified into sufentanil (n = 159) or remifentanil (n = 359) groups according to the opioids administered continuously during anesthesia. The primary outcome assessed in this study was the postoperative pain score measured using the numeric rating scale (NRS). The secondary outcomes assessed included the recovery time (from discontinuation of opioid infusion to extubation) and frequency of rescue analgesic administration in the post-anesthesia care unit (PACU). Results: The recovery time did not differ significantly between the two groups. The NRS score for pain (median [1Q, 3Q]) in the PACU was significantly lower in the sufentanil group than in the remifentanil group (2 [2, 3] vs. 4 [3, 7], P < 0.001). The frequency of rescue analgesic administration in the PACU was 6.3% and 35.4% in the sufentanil and remifentanil groups, respectively (P < 0.001). Conclusions: Sufentanil, as an adjunct to sevoflurane anesthesia is more advantageous than remifentanil in terms of postoperative pain control during robotic gynecological surgery.