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The COVID-19 pandemic is ongoing as of September 2022. Since January 2020 when the first case was reported in Japan, the medical community faced a variety of problems both domestically and internationally. It is meaningful to review the impact of COVID-19 from an anesthesiologist's perspective to clarify our policy for future infectious disease outbreaks. In this year's Journal of Anesthesia (JA) symposium, five experts who were deeply involved in the COVID-19 response reviewed the past 2.5 years and made recommendations for potential future pandemics. Anesthesiologists are specialists in airway management and their role in intubating patients with COVID-19 has received much attention. However, they have also played an important backup role in intensive care as critical care physicians and must be more involved in critical care in regular (non-pandemic) times to properly fulfill this role. It is especially important for the Japan Society of Anesthesiologists and JA to quickly disseminate accurate information on unknown infectious diseases to the medical community and wider society. Therefore, it is important to promptly publish papers that are quality-assured through peer review., (© 2022. The Author(s) under exclusive licence to Japanese Society of Anesthesiologists.)

PHACE syndrome is a neurocutaneous syndrome characterized by the association of large cutaneous hemangiomas and the cardiac and cerebral vascular anomalies. We report a 6-year-old female with PHACE syndrome presented with left facial hemangiomas, cystic lesion in the cerebral posterior fossa, coarctation of the aorta, aplasia of the left vertebral artery and stenosis of the left internal carotid artery. Surgical repair of the aorta with left heart bypass under beating heart was scheduled. We monitored regional cerebral oxygen saturation (rSO2) with infrared spectroscopy in order to detect cerebral hypoperfusion. A decrease of rSO2 ipsilateral to the cerebrovascular anomalies occurred during anastomosis of the aorta, which was treated by reducing the flow rate of left heart bypass and by increasing the inhalational oxygen concentration. As children with PHACE syndrome are frequently accompanied with cerebrovascular anomalies and at a risk of cerebral hypoperfusion, prevention of cerebral hypoperfusion is crucially important during general anesthesia.

Pena-Shokeir syndrome is a rare, early lethal disease. It is characterized by fetal growth restriction; craniofacial deformities, for example micrognathia and microcephaly; multiple ankyloses; and pulmonary hypoplasia. For patients with this syndrome, maintenance of airway and control of perioperative respiratory complications are important for anesthetic management. We report 3 pediatric cases of Pena-Shokeir syndrome undergoing tracheostomy and arthrolysis under general anesthesia using sevoflurane, nitrous oxide, fentanyl, and vecuronium bromide. Anesthetic procedures including mask ventilation, tracheal intubation, and extubation were successfully performed without complications during and after surgery. In patients with Pena-Shokeir syndrome, inhalational anesthetics can be safely used for induction and maintenance of anesthesia, although it is important to assume that difficult airway management might be encountered.

Author(s): Yutaka Oda [sup.1] Author Affiliations: (1) Department of Anesthesiology, Osaka City Juso Hospital, , 2-12-27, Nonaka-kita, Yodogawa-ku, 533-0034, Osaka, Japan Sugammadex is extensively used since its introduction to our [...]

Primary tracheal tumors are rare in adults, and careful airway management is required during anesthesia for affected patients. We report the case of a patient with tracheal hemangiomas undergoing nontracheal operation. A 61-year-old woman was scheduled for a lung operation. During preoperative examination, hemangiomas were detected on the tracheal mucosa. As she was asymptomatic and the degree of airway stenosis was small, treatment was not required for the hemangiomas, and left upper lobectomy for lung cancer was scheduled. After induction of general anesthesia, a regular tracheal tube was inserted under fiberoptic bronchoscopy, with care taken to prevent damage to the hemangiomas. An endobronchial blocker was inserted for one-lung ventilation. The operation was performed uneventfully, and the tracheal tube was replaced postoperatively with a laryngeal mask airway while the patient was under deep anesthesia and neuromuscular blockade. The mask was removed after confirming lack of bleeding from the hemangiomas. No hypoxia or other complications occurred during or after the operation. Keywords Tracheal tumor * Hemangioma * One-lung ventilation * Endobronchial blocker, Introduction Primary tumors of the trachea are rare, and affected individuals are often asymptomatic despite the high level of malignancy [1]. These tumors are commonly discovered during a health checkup [...]

Purpose To examine the relationships between effect-site concentrations and electroencephalographic parameters after the induction of general anesthesia with midazolam. Methods Twenty-four patients with American Society of Anesthesiologists status I or II were randomly allocated to receive either an intravenous (i.v.) bolus of midazolam 0.2 mg [kg.sup.-1] (small-dose group, n = 12) or 0.3 mg [kg.sup.-1] (large-dose group, n = 12) for induction of general anesthesia in a double-blind experimental design. The bispectral index (BIS), 95% spectral edge frequency (SEF95), spectral power density, and plasma concentrations of midazolam were measured for 60 min following the induction of general anesthesia. Results Plasma and simulated effect-site concentrations of midazolam were significantly higher in the large-dose group than in the small-dose group (P = 0.005 and Conclusion Following the induction of general anesthesia with i.v. midazolam 0.2 or 0.3 mg [kg.sup.-1], the BIS was positively correlated with the relative beta ratio. Despite a rapid decrease in the plasma and effect-site concentrations of midazolam, the average BIS remained >60 for 60 min after induction, reflecting an increased power of the electroencephalographic high-frequency band. Keywords Bispectral index * Electroencephalogram * Midazolam * Relative beta ratio * Spectral edge frequency, Introduction Midazolam is used for sedation and general anesthesia [1]. During anesthesia, monitoring of the depth of anesthesia is required in order to maintain an adequate level of anesthesia and [...]

Purpose We examined the hypothesis that remifentanil decreases the bispectral index (BIS) as well as blunts cardiovascular responses to tracheal intubation during anesthesia with midazolam. Methods Sixty patients were randomly allocated to three groups according to the dose of remifentanil-0.1 (S), 0.2 (M), or 0.5 (L) [micro]g [kg.sup.-1] [min.sup.-1], respectively. Infusion of remifentanil was started 5 min before the induction of general anesthesia with midazolam 0.2 mg/kg in all groups. Following the administration of vecuronium 0.1 mg/kg, the trachea was intubated 5 min after induction, and the infusion rate of remifentanil was then reduced to 0.05 [micro]g [kg.sup.-1] [min.sup.-1] in all groups. Mean arterial blood pressure (MAP), heart rate (HR), BIS, and 95% spectral edge frequency (SEF95) were measured until 10 min after tracheal intubation. Results Infusion of remifentanil alone before the induction of anesthesia did not affect the hemodynamic or electroencephalographic parameters. MAP was significantly decreased after induction in all groups of patients (P < 0.01), with no differences among the three groups, while it was significantly increased after tracheal intubation in the patients of groups S and M, but not in those of group L. The HR did not change after induction in any of the groups, but it was also significantly increased after tracheal intubation of group S and M patients, although not in those of group L. The BIS decreased after induction, and both the BIS and SEF95 were significantly lower in group L patients than in those of group S (P < 0.01). All patients were unconscious after induction, and none complained of intraoperative awareness. Conclusion In our patient cohort, remifentanil 0.5 [micro]g [kg.sup.-1] [min.sup.-1] effectively decreased the BIS after the induction of general anesthesia with midazolam 0.2 mg/kg and suppressed the increase of MAP and HR in response to subsequent laryngoscopy and tracheal intubation. Keywords Bispectral index * Electroencephalogram * Midazolam * Remifentanil * Spectral edge frequency, Introduction Remifentanil is a short-acting opioid commonly used in combination with intravenous and volatile anesthetics for the induction and maintenance of general anesthesia. It is known to be effective in [...]

Lipid emulsion infusion is a first-line therapy against the toxicity of local anesthetics and is a potential treatment for other drug overdoses, especially for highly lipophilic drugs. Considering the lipophilic property of volatile anesthetics, we hypothesized that lipid emulsion could reverse general anesthesia. Using adult rats, we tested the effect of lipid emulsion infusion on time to emergence after discontinuation of sevoflurane and isoflurane, and further evaluated restoration of righting reflex under continuous sevoflurane anesthesia. Electroencephalogram during lipid emulsion infusion was also investigated under continuous sevoflurane inhalation. The effect of lipid emulsion on sevoflurane-induced respiratory and hemodynamic depressions was evaluated by measuring respiratory rate, PaCO2 (arterial partial pressure of CO2), blood pressure, and heart rate. The binding property of lipid emulsion on sevoflurane and isoflurane was assessed using in vitro setting with a conical flask. Lipid emulsion infusion significantly decreased time to emergence from sevoflurane anesthesia (131 ± 53 vs. 237 ± 69 s) and restored righting reflex during continuous sevoflurane inhalation, by comparing normal saline infusion. Consistent with the behavioral findings, the electroencephalogram under continuous sevoflurane showed decreased power of the δ bands at 5 min after the initiation of lipid emulsion infusion. In addition to reversing hypnosis, lipid emulsion recovered respiratory as well as hemodynamic depressions induced by sevoflurane. Decreased time to emergence was observed also in isoflurane anesthesia (203 ± 111 vs. 314 ± 154 s). To investigate the binding mechanism of lipid emulsion infusion, in vitro experiments revealed significantly decreased anesthetic concentrations of sevoflurane and isoflurane by mixing with lipid emulsion. Lipid emulsion facilitated reversal from volatile anesthetics, as shown by several parameters. As lipid emulsion could bind to volatile anesthetics and simply decrease their effects, our findings suggest that lipid emulsion is a potentially useful agent to reverse general anesthesia. [ABSTRACT FROM AUTHOR]

Purpose: We examined the hypothesis that 1 minimum alveolar concentration (MAC) of desflurane and sevoflurane provides different depth of anesthesia. Methods: One hundred and twenty young (20-30 years), middle-aged (31-65 years), and elderly (66-80 years) patients were randomly allocated to receive either desflurane or sevoflurane ( n = 20, each group). General anesthesia was induced with propofol 2 mg/kg bolus and remifentanil 0.25 µg/kg/min, which was stopped after tracheal intubation. Maintenance of anesthesia was started with an end-tidal concentration of desflurane or sevoflurane at age-adjusted 1 MAC and maintained for 10 min, followed by 1-min assessment of bispectral index (BIS), 95% spectral edge frequency (SEF95), and amplitude of the electroencephalogram taken at 10-s intervals. Results: BIS and SEF95 in patients receiving 1 MAC desflurane were significantly lower than those receiving 1 MAC sevoflurane including all age groups [35 (29, 39) vs. 41 (38, 49); 12.53 (10.99, 13.95) Hz vs. 14.42 (12.99, 17.17) Hz median (25, 75 percentile), respectively, P < 0.001 for both]. Both BIS and SEF95 in young patients were lower than in middle-aged and elderly patients receiving either desflurane or sevoflurane ( P < 0.001 for both). There were no differences in amplitude between patients receiving desflurane and sevoflurane. Conclusions: BIS as well as SEF95 were lower in patients receiving 1 MAC desflurane than those receiving 1 MAC sevoflurane, suggesting that desflurane provides higher depth of anesthesia than sevoflurane at 1 MAC. [ABSTRACT FROM AUTHOR]

The author comments on the impact of the use of long-acting local anesthetics for both neuraxial and peripheral nerve block in children. Long-acting local anesthetics such as bupivacaine, levobupivacaine and ropivacaine have higher toxic potency than lidocaine. Research on toxicity and pharmacokinetics in children would help avoid adverse effects and improve the quality of anesthesia practice.

24-year-old man underwent surgery for a fractured left clavicle and received an interscalene brachial plexus block for intraoperative and postoperative analgesia. After injection of 40 ml 0.5% ropivacaine and confirmation of analgesia, general anesthesia was induced and maintained with propofol. Although the operation was completed uneventfully, the patient was restless and there was limb twitching during emergence from anesthesia. Ropivacaine-induced toxicity was suspected, and a dose of 100 ml 20% lipid emulsion was infused intravenously. The symptoms of toxicity disappeared, and there was full recovery of consciousness within 5 min. Plasma concentrations of total and protein-unbound ropivacaine measured 2 h 20 min after local injection were 1.99 and 0.13 μg/ml, respectively. After infusion of lipid emulsion, the ropivacaine concentrations decreased to 1.72 and 0.05 μg/ml, respectively. The patient had no pain, and neurological examination revealed sensory loss around the clavicle. The patient was discharged without any complications. [ABSTRACT FROM AUTHOR]