Background: As the global population ages, medical professionals are also aging. This study investigates the status of Korean anesthesiologists over the age of 60. Methods: Anesthesiologists aged 60 and older, residing and working in Korea, were invited to participate in this study via e-mail from February to March 2021 and by mail from June to August 2021. The survey consisted of 40 questions covering 10 topics, including health status, residence, work style, and economic status. Depending on the type of question, answers were ranked on a scale of 1, 2, and 3, with the most preferred response being selected. Results: A total of 63 responses were received, resulting in a response rate of 26.5%. Among the respondents, 56 were currently practicing as anesthesiologists and reported satisfaction with their clinical practice and life status. On average, they treated 24 patients per day without experiencing significant discomfort or inconvenience in their roles as senior physicians. Twenty-four respondents acknowledged physical discomfort related to aging, and nine expressed cautions regarding age-related changes. Fifty-two respondents indicated that reeducation for advanced medical practice as anesthesiologists was necessary. Conclusions Senior anesthesiologists in Korea are primarily working in secondary and tertiary hospitals and are satisfied with their current life status. A comprehensive evaluation of reeducation programs for advanced clinical practice and retirement strategies for senior anesthesiologists is needed to address the growing number of aging physicians in the workforce.

A booster dose can result in a similar reaction to the initial dose. Neuromuscular blocking agents (NMBAs) can produce a comparable reaction in the absence of specific pathophysiologic alterations. Case: An initial dose of rocuronium 40 mg was given to a male patient (50 years old, height 168 cm, weight 54 kg, body mass index 19.13 kg/m2 ) for anesthesia. The onset was usual, but the duration was brief. Two booster doses were administered at 20 min intervals, but recovery came quickly. So, acute tolerance was suspected. Muscle function was restored to greater than train-of-four ratio 0.75 while spontaneous aided breathing was maintained without the need of further NMBAs. Following the operation, sugammadex (1.85 mg/kg) was provided to prevent residual neuromuscular inhibition. Conclusions: Anesthetists must be able to suspect acute tolerance to NMBAs in patients with no unique medical history and have a plan to resolve it.

A booster dose can result in a similar reaction to the initial dose. Neuromuscular blocking agents (NMBAs) can produce a comparable reaction in the absence of specific pathophysiologic alterations. Case: An initial dose of rocuronium 40 mg was given to a male patient (50 years old, height 168 cm, weight 54 kg, body mass index 19.13 kg/m2 ) for anesthesia. The onset was usual, but the duration was brief. Two booster doses were administered at 20 min intervals, but recovery came quickly. So, acute tolerance was suspected. Muscle function was restored to greater than train-of-four ratio 0.75 while spontaneous aided breathing was maintained without the need of further NMBAs. Following the operation, sugammadex (1.85 mg/kg) was provided to prevent residual neuromuscular inhibition. Conclusions: Anesthetists must be able to suspect acute tolerance to NMBAs in patients with no unique medical history and have a plan to resolve it.

A booster dose can result in a similar reaction to the initial dose. Neuromuscular blocking agents (NMBAs) can produce a comparable reaction in the absence of specific pathophysiologic alterations. Case: An initial dose of rocuronium 40 mg was given to a male patient (50 years old, height 168 cm, weight 54 kg, body mass index 19.13 kg/m2 ) for anesthesia. The onset was usual, but the duration was brief. Two booster doses were administered at 20 min intervals, but recovery came quickly. So, acute tolerance was suspected. Muscle function was restored to greater than train-of-four ratio 0.75 while spontaneous aided breathing was maintained without the need of further NMBAs. Following the operation, sugammadex (1.85 mg/kg) was provided to prevent residual neuromuscular inhibition. Conclusions: Anesthetists must be able to suspect acute tolerance to NMBAs in patients with no unique medical history and have a plan to resolve it.

A booster dose can result in a similar reaction to the initial dose. Neuromuscular blocking agents (NMBAs) can produce a comparable reaction in the absence of specific pathophysiologic alterations. Case: An initial dose of rocuronium 40 mg was given to a male patient (50 years old, height 168 cm, weight 54 kg, body mass index 19.13 kg/m2 ) for anesthesia. The onset was usual, but the duration was brief. Two booster doses were administered at 20 min intervals, but recovery came quickly. So, acute tolerance was suspected. Muscle function was restored to greater than train-of-four ratio 0.75 while spontaneous aided breathing was maintained without the need of further NMBAs. Following the operation, sugammadex (1.85 mg/kg) was provided to prevent residual neuromuscular inhibition. Conclusions: Anesthetists must be able to suspect acute tolerance to NMBAs in patients with no unique medical history and have a plan to resolve it.

A booster dose can result in a similar reaction to the initial dose. Neuromuscular blocking agents (NMBAs) can produce a comparable reaction in the absence of specific pathophysiologic alterations. Case: An initial dose of rocuronium 40 mg was given to a male patient (50 years old, height 168 cm, weight 54 kg, body mass index 19.13 kg/m2 ) for anesthesia. The onset was usual, but the duration was brief. Two booster doses were administered at 20 min intervals, but recovery came quickly. So, acute tolerance was suspected. Muscle function was restored to greater than train-of-four ratio 0.75 while spontaneous aided breathing was maintained without the need of further NMBAs. Following the operation, sugammadex (1.85 mg/kg) was provided to prevent residual neuromuscular inhibition. Conclusions: Anesthetists must be able to suspect acute tolerance to NMBAs in patients with no unique medical history and have a plan to resolve it.

Background: The Omicron variant has become the most prevalent SARS-CoV-2 variant. Omicron is known to induce milder lesions compared to the original Wuhan strain. Fatal infection of the Wuhan strain into the brain has been well documented in COVID-19 mouse models and human COVID-19 cases, but apparent infections into the brain by Omicron have not been reported in human adult cases or animal models. In this study, we investigated whether Omicron could spread to the brain using K18-hACE2 mice susceptible to SARS-CoV-2 infection. Results: K18-hACE2 mice were intranasally infected with 1 × 105 PFU of the original Wuhan strain and the Omicron variant of SARS-CoV-2. A follow-up was conducted 7 days post infection. All Wuhan-infected mice showed > 20% body weight loss, defined as the lethal condition, whereas two out of five Omicron-infected mice (40%) lost > 20% body weight. Histopathological analysis based on H&E staining revealed inflammatory responses in the brains of these two Omicron-infected mice. Immunostaining analysis of viral nucleocapsid protein revealed severe infection of neuron cells in the brains of these two Omicron-infected mice. Lymphoid depletion and apoptosis were observed in the spleen of Omicron-infected mice with brain infection. Conclusion Lethal conditions, such as severe body weight loss and encephalopathy, can occur in Omicron-infected K18-hACE2 mice. Our study reports, for the first time, that Omicron can induce brain infection with lymphoid depletion in the mouse COVID-19 model.