Comparison of the effects of intraoperative remifentanil and sufentanil infusion on postoperative pain management in robotic gynecological surgery: a retrospective cohort study.

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.

The Effect of Neuromuscular Blockade Reversal Agents on Postoperative Pulmonary Complications in Patients undergoing Femur Fracture Repair Surgery: A Retrospective Observational Study.

BACKGROUND: Femoral fracture repair surgery under general anesthesia is associated with postoperative pulmonary complications (PPCs). However, information on PPCs caused by residual neuromuscular blockade following perioperative use of neuromuscular blockers is limited. This study aimed to identify the differences in the incidence of PPCs according to the type of neuromuscular blockade reversal agent used in femoral fracture repair surgery, as well as the risk factors for PPCs. METHODS: We retrospectively analyzed the electronic medical records of 604 patients aged >18 years who underwent general anesthesia for femoral fracture repair surgery at a single university hospital between March 2017 and March 2022. Patients in whom sugammadex or anticholinesterase was used to reverse the neuromuscular block were subjected to propensity score matching. Multivariate logistic regression analysis was performed to identify risk factors for PPCs. RESULTS: Among the 604 patients, 108 were matched in each group. The incidence rates of PPCs overall and in the anticholinesterase and sugammadex groups were 7.0%, 8.3%, and 5.6%, respectively, with no significant differences between the groups. Older age, higher ASA (American Society of Anesthesiologists) physical status, and lower preoperative oxygen saturation were risk factors, whereas emergency surgery was a preventive factor. CONCLUSIONS: Our results demonstrated that the incidence of PPC did not differ significantly between sugammadex and anticholinesterase in patients undergoing femur fracture repair under general anesthesia. Identifying the risk factors and confirming complete recovery from neuromuscular blockade might be more important.

Cor triatriatum sinister diagnosed in a patient with postoperative cerebral infarction after beach chair position: A case report.

Cor triatriatum sinister is a rare congenital heart disease in which the left atrium is divided into two compartments by a fibromuscular membrane. In most cases, its symptoms appear in childhood, and it is rarely diagnosed in adulthood. Patients with cor triatriatum sinister are more prone to neurological diseases, such as cerebral infarction. Herein, we report the case of a patient whose cor triatriatum sinister went undiagnosed in the preoperative evaluation, but was diagnosed whilst investigating a cerebral infarction that occurred following a surgery in the beach chair position. It highlights the potential complications in otherwise healthy asymptomatic patients undergoing surgery in the beach chair position. Additionally, in high-risk patients, the provision of clear communication, in advance, regarding potential complications and their management, may reduce the patient's morbidity.

Clinical efficacy of short-term prewarming in elderly and adult patients: A prospective observational study.

Background: Short-term prewarming effectively reduces intraoperative hypothermia in adult patients. However, few data exist regarding its efficacy in elderly patients. Elderly people have a reduced ability to regulate their body temperature, which affects the efficacy of prewarming. This study aimed to compare the clinical efficacy of short-term pre-warming in elderly patients with that in adult patients. Methods: We enrolled 25 adult (20-50 years) and 25 elderly (> 65 years) patients scheduled for ureteroscopic stone surgery under general anaesthesia. All patients received preanaesthetic forced-air warming for 20 min. The core temperature was measured using an infrared tympanic thermometer during awakening and nasopharyngeal thermistors during anaesthesia. Incidence and severity of intraoperative hypothermia (< 36°C) was compared. Postoperative shivering and number of patients requiring active warming in the post-anaesthesia care unit were also assessed. Results: Intraoperative hypothermia was more frequent in elderly than in adult patients (58.3% vs. 12.0%; relative risk 2.6; 95% confidence interval 1.5 to 4.6; effect size h = 1.010; p = 0.001). The severity of intraoperative hypothermia showed a significant intergroup difference (p = 0.002). Postoperative shivering was more frequent in elderly than in adult patients (33.3% vs. 8.0%, p = 0.037). A greater number of elderly patients in the post-anaesthesia care unit required active warming (33.3% vs. 8.0%, p = 0.037). Conclusions: The effects of short-term prewarming on the prevention of hypothermia and maintenance of perioperative normothermia are not the same in the elderly and adult patients.

Comparison of the effects of dexmedetomidine and propofol on hypothermia in patients under spinal anesthesia: a prospective, randomized, and controlled trial.

Background: Redistribution hypothermia caused by vasodilation during anesthesia is the primary cause of perioperative hypothermia. Propofol exerts a dose-dependent vasodilatory effect, whereas dexmedetomidine induces peripheral vasoconstriction at high plasma concentrations. This study compared the effects of dexmedetomidine and propofol on core temperature in patients undergoing surgery under spinal anesthesia. Methods: This prospective study included 40 patients (aged 19-70 years) with American Society of Anesthesiologists Physical Status class I-III who underwent elective orthopedic lower-limb surgery under spinal anesthesia. Patients were randomly allocated to a dexmedetomidine or propofol group (n = 20 per group). After induction of spinal anesthesia, patients received dexmedetomidine (loading dose: 1 µg/kg over 10 min; maintenance dose: 0.2-0.7 µg/kg/h) or propofol (loading dose: 75 µg/kg over 10 min; maintenance dose: 12.5-75 µg/kg/min). The doses of sedatives were titrated to maintain moderate sedation. During the perioperative period, tympanic temperatures, thermal comfort score, and shivering grade were recorded. Results: Core temperature at the end of surgery did not differ significantly between the groups (36.4 ± 0.4 and 36.1 ± 0.7°C in the dexmedetomidine and propofol groups, respectively; P = 0.118). The lowest perioperative temperature, incidence and severity of perioperative hypothermia, thermal comfort score, and shivering grade did not differ significantly between the groups (all P > 0.05). Conclusions: In patients undergoing spinal anesthesia with moderate sedation, the effect of dexmedetomidine on patients' core temperature was similar to that of propofol.

Prewarming for Prevention of Hypothermia in Older Patients Undergoing Hand Surgery Under Brachial Plexus Block.

BACKGROUND: Older patients are more vulnerable to inadvertent perioperative hypothermia. Prewarming contributes to the prevention of inadvertent perioperative hypothermia in patients under general or neuraxial anesthesia. However, the effects of brachial plexus block (BPB) on thermoregulation and the efficacy of prewarming in the prevention of hypothermia in older patients undergoing surgery with BPB remain unclear. This study evaluated the effects of BPB on thermoregulation and the efficacy of prewarming during BPB in older patients. METHODS: Patients aged ≥65 years were randomly allocated to receive either standard preoperative insulation (control group, n=20) or preanesthetic forced-air warming for 20 minutes before BPB (prewarming group, n=20). During the perioperative period, tympanic temperatures were measured. Thermal comfort scores and shivering grades were also obtained. RESULTS: The tympanic temperatures at the end of surgery did not differ between the groups (36.9°C±0.5°C and 37.0°C±0.4°C in the control and prewarming groups, respectively; p=0.252). The maximum temperature change was significantly lower in the prewarming group compared to the control group (0.36°C±0.4°C and 0.65°C±0.3°C, respectively; p=0.013). The hypothermia incidence and severity, thermal comfort scores, and shivering grades did not differ between the groups. CONCLUSION: Regardless of the application of prewarming, BPB did not cause a clinically significant impairment of thermoregulation. Moreover, the efficacy of prewarming appeared to be low; thus, it may not be routinely required in patients undergoing orthopedic hand surgery under BPB.

Postoperative Analgesic Effectiveness of Peripheral Nerve Blocks in Cesarean Delivery: A Systematic Review and Network Meta-Analysis.

The purpose of this systematic review and network meta-analysis was to determine the analgesic effectiveness of peripheral nerve blocks (PNBs), including each anatomical approach, with or without intrathecal morphine (ITMP) in cesarean delivery (CD). All relevant randomized controlled trials comparing the analgesic effectiveness of PNBs with or without ITMP after CD until July 2021. The two co-primary outcomes were designated as (1) pain at rest 6 h after surgery and (2) postoperative cumulative 24-h morphine equivalent consumption. Secondary outcomes were the time to first analgesic request, pain at rest 24 h, and dynamic pain 6 and 24 h after surgery. Seventy-six studies (6278 women) were analyzed. The combined ilioinguinal nerve and anterior transversus abdominis plane (II-aTAP) block in conjunction with ITMP had the highest SUCRA (surface under the cumulative ranking curve) values for postoperative rest pain at 6 h (88.4%) and 24-h morphine consumption (99.4%). Additionally, ITMP, ilioinguinal-iliohypogastric nerve block in conjunction with ITMP, lateral TAP block, and wound infiltration (WI) or continuous infusion (WC) below the fascia also showed a significant reduction in two co-primary outcomes. Only the II-aTAP block had a statistically significant additional analgesic effect compared to ITMP alone on rest pain at 6 h after surgery (-7.60 (-12.49, -2.70)). In conclusion, combined II-aTAP block in conjunction with ITMP is the most effective post-cesarean analgesic strategy with lower rest pain at 6 h and cumulative 24-h morphine consumption. Using the six described analgesic strategies for postoperative pain management after CD is considered reasonable. Lateral TAP block, WI, and WC below the fascia may be useful alternatives in patients with a history of sensitivity or severe adverse effects to opioids or when the CD is conducted under general anesthesia.

Effects of dexamethasone on catheter-related bladder discomfort and emergence agitation: a prospective, randomized, controlled trial.

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.

Effects of chlorpheniramine on emergence agitation after general anesthesia for ureteroscopic stone surgery: a retrospective cohort study.

BACKGROUND: The presence of a urinary catheter, postoperative pain, and postoperative nausea and vomiting are risk factors for emergence agitation (EA). Antimuscarinic agents are primary agents used in the prevention and treatment of urinary catheter-related bladder discomfort. Chlorpheniramine has antimuscarinic, antinociceptive, and antiemetic effects. This retrospective study investigated the role of chlorpheniramine in EA prevention following ureteroscopic stone surgery. METHODS: Of 110 adult patients who underwent ureteroscopic stone surgery under general anesthesia between January and December 2019, the medical records of 93 patients were analyzed retrospectively. The patients were divided into control (n = 52) and chlorpheniramine (n = 41) groups according to the receipt of intravenous chlorpheniramine before the induction of anesthesia. The incidence and severity of EA were compared between the groups as primary and secondary endpoints, respectively. The effects of chlorpheniramine on the requirement for inhalation anesthetic (desflurane) during surgery, changes in mean blood pressure and heart rate during emergence, and adverse events were also compared. RESULTS: The incidence (21.2% in the control group, 24.4% in the chlorpheniramine group) and severity of EA did not differ between groups. The intraoperative requirement for desflurane, changes in mean blood pressure and heart rate during emergence, and adverse events were also similar between groups. CONCLUSIONS: Chlorpheniramine was not associated with a decrease in EA incidence or severity in patients who underwent ureteroscopic stone surgery.

Effects of neuromuscular blocking agents on the clinical performance of i-gel® and surgical condition in elderly patients undergoing hand surgery: a prospective randomized controlled trial.

Background: The effects of neuromuscular blocking agents on the clinical performance of supraglottic airway devices and surgical condition in elderly patients undergoing hand surgery have not been established. We evaluated the effects of rocuronium on the clinical performance of an i-gel® supraglottic device and surgical condition in elderly patients undergoing orthopedic hand surgery. Methods: Patients aged 65-85 years were randomized to receive either rocuronium (rocuronium group) or saline (control group). We compared the rates of successful insertion of the i-gel on the first attempt as a primary outcome and also assessed the adequacy of i-gel maintenance during controlled ventilation, anesthetic requirement, surgical condition, and recovery time. Results: The rates of successful insertion of the i-gel on a first attempt were 93.1% in the rocuronium group versus 82.1% in the control group (P = 0.423). Peak inspiratory pressure (PIP) was lower in the rocuronium group than in the control group (15.2 vs. 17.9 cmH2O, respectively, P = 0.028). Spontaneous breathing was less common in the rocuronium group (24.1% vs. 57.1%, respectively, P = 0.011). The requirement of additional fentanyl to suppress spontaneous breathing or patient movement was less in the rocuronium group than in the control group (24.1% vs. 50.0%, respectively, P = 0.043). Surgical condition did not differ between the two groups. Recovery time was shorter in the rocuronium group than in the control group (8.4 vs. 9.9 min, respectively, P = 0.030). Conclusions: Rocuronium did not enhance the success rate of inserting the i-gel® or the surgical condition in elderly patients. However, using rocuronium reduced PIP, the frequency of spontaneous breathing, the requirement for additional fentanyl and patients' recovery time.

Incidence of postoperative hypothermia and its risk factors in adults undergoing orthopedic surgery under brachial plexus block: A retrospective cohort study.

Postoperative hypothermia increases patient mortality and morbidity. However, the incidence of, and risk factors for, postoperative hypothermia in patients undergoing surgery under brachial plexus block (BPB) as the primary method of anesthesia remain unclear. This study aimed to determine the incidence of, and risk factors for, postoperative hypothermia in patients undergoing surgery under BPB. We retrospectively analyzed 660 patients aged ≥ 19 years who underwent orthopedic surgery under BPB in our hospital between October 2014 and October 2019. Postoperative hypothermia was defined as a tympanic membrane temperature < 36 °C when the patient arrived in the post-anesthesia care unit. Multivariate logistic regression analysis was performed to identify the independent risk factors for postoperative hypothermia. Postoperative hypothermia was observed in 40.6% (268/660) of patients. Independent risk factors for postoperative hypothermia were lower baseline core temperature before anesthesia (odds ratio [OR] 0.355; 95% confidence interval [CI] 0.185-0.682), alcohol abuse (OR 2.658; 95% CI 1.105-6.398), arthroscopic shoulder surgery (OR 2.007; 95% CI 1.428-2.820), use of fentanyl (OR 1.486; 95% CI 1.059-2.087), combined use of midazolam and dexmedetomidine (OR 1.816; 95% CI 1.268-2.599), a larger volume of intravenous fluid (OR 1.001; 95% CI 1.000-1.002), and longer duration of surgery (OR 1.010; 95% CI 1.004-1.017). Postoperative hypothermia is common in adult patients undergoing orthopedic surgery under BPB. The risk factors identified in this study should be considered to avoid postoperative hypothermia in these patients.

Comparison of the effect of general and spinal anesthesia for elective cesarean section on maternal and fetal outcomes: a retrospective cohort study.

BACKGROUND: Anesthesia is needed to ensure both maternal and fetal safety during cesarean sections. This retrospective cohort study compared maternal and fetal outcomes between general and spinal anesthesia for cesarean section based on perioperative hemodynamic parameters (pre- and postoperative systolic blood pressure, heart rate), mean difference of hematocrit and estimated blood loss, and neonatal Apgar scores at 1 and 5 min. METHODS: Data from electronic medical records of 331 singleton pregnancies between January 2016 and December 2018 were analyzed retrospectively; 44 cases were excluded, and 287 cases were assigned to the general group (n = 141) or spinal group (n = 146). RESULTS: Postoperative hemodynamic parameters were significantly higher in the general group than the spinal group (systolic blood pressure: 136.8 ± 16.7 vs. 119.3 ± 12.7 mmHg, heart rate: 93.2 ± 16.8 vs. 71.0 ± 12.7 beats/min, respectively, P < 0.001). The mean difference between the pre- and postoperative hematocrit was also significantly greater in the general than spinal group (4.8 ± 3.4% vs. 2.3 ± 3.9%, respectively, P < 0.001). The estimated blood loss was significantly lower in the spinal than general group (819.9 ± 81.9 vs. 856.7 ± 117.9 ml, P < 0.001). There was a significantly larger proportion of newborns with 5-min Apgar scores < 7 in the general than spinal group (6/141 [4.3%] vs. 0/146 [0%], respectively, P = 0.012). CONCLUSIONS: General group is associated with more maternal blood loss and a larger proportion of newborns with 5-min Apgar scores < 7 than spinal group during cesarean sections.

Effects of Chlorpheniramine Maleate on Catheter-Related Bladder Discomfort in Patients Undergoing Ureteroscopic Stone Removal: A Randomized Double-Blind Study.

Catheter-related bladder discomfort (CRBD) associated with intraoperative urinary catheterization is a distressing symptom during recovery from anesthesia. Anticholinergics have been used to manage CRBD. Chlorpheniramine maleate (CPM) is a first-generation antihistamine, which also has anticholinergic effects. This study was undertaken to evaluate the efficacy of CPM in preventing CRBD. Seventy-six adults (19-65 years old) with American Society of Anesthesiologists physical status I, II, or III of either sex, undergoing elective ureteroscopic stone removal under general anesthesia were randomized into one of two groups (each n = 38). Group C (control) received a placebo, and group CPM received 8 mg of intravenous CPM before the induction of anesthesia. CRBD was assessed upon arrival in the post-anesthetic care unit at 0, 1, 2, and 6 h. The severity of CRBD was graded as none, mild, moderate, and severe. Tramadol was administered when the severity of CRBD was more than moderate. The incidence rate and overall severity of CRBD did not differ between the groups at any of the time points (р > 0.05). The incidence of moderate CRBD was higher in group C than in group CPM only at 0 h (26.3% vs. 5.3%, р = 0.025). However, fewer patients in the CPM group required rescue tramadol to relieve CRBD after surgery (31.6% vs. 60.5%, р = 0.011). CPM administration before the induction of anesthesia had little effect on the incidence and severity of CRBD after surgery, but it reduced the administration of tramadol required to control CRBD postoperatively.

Comparison of emergence agitation between succinylcholine and rocuronium-sugammadex in adults following closed reduction of a nasal bone fracture: a prospective randomized controlled trial.

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; each n = 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 number KCT0002673. Initial registration date was 31 January 2018 (Retrospectively registered).

Comparative Analysis of Anesthetic Legal Disputes between Older and Younger Patients Referred to the Korean Society of Anesthesiologists in 2009-2018.

BACKGROUND: Although the average age of patients undergoing surgical procedures or anesthesia is increasing, differences in anesthesia-related injuries among different age groups have been not reported. This study compared older and younger patients on the basis of disputes regarding anesthesia-related injuries referred to the Korean Society of Anesthesiologists (KSA). METHODS: We retrospectively analyzed disputes regarding anesthesia-related injuries referred to the KSA between 2009 and 2018. After excluding duplicates, incomplete data, local anesthesia cases, and patients aged ≤18 or 55-64 years, the subjects were divided into older (≥65 years) and younger (19-54 years) age groups. The parameters included in the KSA database were compared between these two groups. RESULTS: The 115 cases included in the study included 28 and 87 cases from the older and younger groups, respectively. The proportions of preventable cases of anesthesia-related adverse events differed significantly between the older (25%) and younger groups (48.3%). The most common medical disputes in the older group were related to general anesthesia, orthopedic surgery, local hospitals, and anesthesiologist, whereas those in the younger group were related to sedation, plastic surgery, local clinics, and non-anesthesiologists. CONCLUSION: In addition to understanding the differences in anesthesia characteristics according to age group, it is also necessary to develop means for reducing preventable anesthesia-related adverse events. Furthermore, we must continue to register anesthesia-related disputes, and a voluntary reporting system should be established to prevent anesthesia-related accidents.

Trends in medical disputes involving anesthesia during July 2009-June 2018: an analysis of the Korean Society of Anesthesiologists database.

BACKGROUND: To identify trends in injuries and substandard care associated with anesthesia, we analyzed the Korean Society of Anesthesiologists database for anesthesia-related case files from July 2009 to June 2018. METHODS: Case characteristics, injuries, and outcomes were compared between the first part (July 2009-June 2014, n = 105) and the second part (July 2014-June 2018, n = 92) of the analyzed time period. RESULTS: Overall, 132 cases resulted in death. The proportion of fatal cases for sedation was similar to general anesthesia (66.2% vs. 76.3%). The proportion of cases with permanent injury or death decreased significantly in the second part of the period compared with the first part (76.1% vs. 93.3%, P = 0.002). With a growing trend in the proportion of sedation cases, a similar number of sedation and general anesthesia cases were referred during the overall period (77 and 76 cases, respectively). Propofol-based regimens remained the dominant sedation method (89.7% in the first part vs. 78.9% in the second part). The most common adverse event in cases of permanent injury or death was identified as being respiratory in origin (98/182, 53.8%). Permanent injuries or deaths were related to local anesthetic systemic toxicity (LAST) and beach-chair positioning for shoulder surgery, in 8 and 5 cases, respectively. CONCLUSIONS: Despite the decreasing trend in injury severity with time, several characteristic injury profiles were identified: lack of vigilance in propofol-based sedation, neurological injuries related to the beach-chair position, and LAST occurring during tumescent anesthesia or brachial plexus block.

Comparison of the clinical performance of airway management with the i-gel® and laryngeal mask airway SupremeTM in geriatric patients: a prospective and randomized study.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

The effect of magnesium sulfate concentration on the effective concentration of rocuronium, and sugammadex-mediated reversal, in isolated left phrenic nerve hemi-diaphragm preparations from the rat.

BACKGROUND: Perioperative magnesium sulfate (MgSO4) is used for analgesic, anti-arrhythmic, and obstetric purposes. The effects of MgSO4 on the neuromuscular blockade (NMB) induced by rocuronium, and the sugammadex reversal thereof, have not been clearly quantified. We investigated the effect of various MgSO4 concentrations on the NMB by rocuronium, and sugammadex reversal, in isolated left phrenic nerve hemi-diaphragm (PNHD) preparations from the rat. METHODS: Rat PNHD preparations were randomly allocated to one of four groups varying in terms of MgSO4 concentration (1, 2, 3, and 4 mM, each n = 10, in Krebs solution). The train-of-four (TOF) and twitch height responses were recorded mechanomyographically. The preparations were treated with incrementally increasing doses of rocuronium and each group's effective concentration (EC)50, EC90, and EC95 of rocuronium were calculated via nonlinear regression. Then, sugammadex was administered in doses equimolar to rocuronium. The recovery index, time to T1 height > 95% of control, and the time to a TOF ratio > 0.9 after sugammadex administration were measured. RESULTS: The EC50, EC90, and EC95 of rocuronium fell significantly as the magnesium level increased. The EC50, EC90, and EC95 of rocuronium did not differ between the 3 and 4 mM groups. The recovery index, time to T1 height > 95% of control, and time to a TOF ratio > 0.9 after sugammadex administration did not differ among the four groups. CONCLUSIONS: Increases in the magnesium concentration in rat PNHD preparations proportionally enhanced the NMB induced by rocuronium but did not affect reversal by equimolar amounts of sugammadex.

Optimal propofol dosage for i-gel® insertion in healthy paralyzed patients.

BACKGROUND: Propofol is used for supraglottic airway device insertion, often with the i-gel. However, the propofol requirement for i-gel insertion has not been explored in paralyzed patients. This study was performed to explore hemodynamic changes and sedation level with different propofol doses in healthy paralyzed patients when the i-gel was inserted. METHODS: A total of 141 patients undergoing a urologic operation were randomly allocated to three groups depending on the propofol dose (1.5, 2, and 2.5 mg/kg; Groups P1.5, P2, and P2.5, respectively). After patients had been administered each propofol dose and rocuronium, the i-gel was inserted and changes in hemodynamic parameters and bispectral index were evaluated. RESULTS: Group P2 showed a lower incidence of complications (17%) such as hemodynamic instability and inadequate sedation than Group P1.5 (55.3%, P < 0.001) or Group P2.5 (40.4%, P = 0.012). The incidence and dose of additional propofol increased in Group P1.5 (51%, median [range]; 20 [0-50]) compared with those in the other groups (0%, 0 [0-0] in Group P2 and 8.5%, 0 [0-50] in Group P2.5, all P < 0.001), and the incidence and dose of additional ephedrine were significantly higher in Group P2.5 (31.9%; 0 [0-20]) than in Group P1.5 (10.6%, P = 0.012; 0 [0-5], P = 0.007, respectively). CONCLUSIONS: For the stable maintenance of hemodynamic parameters and proper sedation level during i-gel insertion, 2 mg/kg propofol has an advantage over 1.5 mg/kg or 2.5 mg/kg propofol in healthy paralyzed patients.

Effects of magnesium chloride on rocuronium-induced neuromuscular blockade and sugammadex reversal in an isolated rat phrenic nerve-hemidiaphragm preparation: An in-vitro study.

BACKGROUND: Magnesium potentiates the effects of nondepolarising muscle relaxants. However, few studies have used magnesium chloride (MgCl2). Sugammadex reverses neuromuscular block by steroidal nondepolarising muscle relaxants. OBJECTIVES: To assess the effects of MgCl2 on rocuronium-induced neuromuscular blockade and its reversal by sugammadex. DESIGN: In-vitro experimental study. SETTING: Animal laboratory, Asan Medical Center, Seoul, South Korea, from 20 March 2016 to 3 April 2016. ANIMALS: Forty male Sprague Dawley rats. INTERVENTION: Left phrenic nerve-hemidiaphragms from 40 Sprague Dawley rats were allocated randomly to four groups (1, 2, 3 and 4 mmol l MgCl2 group, n = 10 each). Rocuronium was administered cumulatively until the first twitch of train-of-four (TOF) disappeared completely. Then, equimolar sugammadex was administered. MAIN OUTCOME MEASURES: The effective concentration (EC) of rocuronium was obtained in each group. After administering sugammadex, recovery of the first twitch height and the TOF ratio were measured for 30 min. RESULTS: EC50, EC90 and EC95 significantly decreased as the concentration of MgCl2 increased (all P ≤ 0.001), except the comparison between the 3 and 4 mmol l MgCl2 groups. After administration of sugammadex, the maximal TOF ratio (%) was lower in the 4 mmol l MgCl2 group than the 1 mmol l MgCl2 group [median 91.7 interquartile range (83.4 to 95.8) vs. 98.3 interquartile range (92.2 to 103.4), P = 0.049]. The mean time (s) from sugammadex injection to achieving maximal first twitch was significantly prolonged in the 4 mmol l MgCl2 group vs. the 1 mmol l MgCl2 and 2 mmol l MgCl2 groups [1483.9 (±â€Š237.0) vs. 1039.0 (±â€Š351.8) and 926.0 (±â€Š278.1), P = 0.022 and 0.002, respectively]. CONCLUSION: Increases in MgCl2 concentration reduce the ECs of rocuronium. In addition, administering sugammadex equimolar to the administered rocuronium shows limited efficacy as MgCl2 concentration is increased. TRIAL REGISTRATION: The in-vitro study was not registered in a database.