COVID-19 Endemic Plan: Impact of Vaccination and Non-pharmaceutical Interventions with Viral Variants and Waning Immunity Using an Agent-Based Simulation

BackgroundsDespite the widespread distribution of SARS-CoV-2 vaccines, the COVID-19 pandemic continues with highly contagious variants and waning immunity. Low disease severity of the Omicron variant gives society hope that the COVID-19 pandemic could end. MethodsWe develop an agent-based simulation to explore the impact of COVID-19 vaccine willingness, booster vaccination schedule, vaccine effectiveness, and non-pharmaceutical interventions (NPIs) on reducing COVID-19 deaths while considering immunity duration and disease severity against the Omicron variant. The model is calibrated to the greater Seattle in year 2020 by observing local epidemic data. The simulation is run to the end of year 2024 to observe long-term effects. ResultsResults show that an NPI policy that maintains low levels of NPIs can reduce mortality by 35.1% compared to fully opening the society. A threshold NPI policy is especially helpful when the disease severity of the Omicron variant is high, or booster vaccines are not scheduled. A periodic booster schedule is needed to achieve the goal of lowering the number of deaths from COVID-19 to the level of influenza and pneumonia. Except for one scenario, 80% or more vaccine willingness is also needed to achieve this goal. ConclusionsWe find that a periodic booster vaccination schedule and mild disease severity of the Omicron variant play a crucial role in reducing deaths by the end of year 2024. If a booster schedule is not planned and the Omicron variant is not mild, NPI policies that limit society from fully opening are required to control the outbreak.

COVID-19 Pandemic Response Simulation: Impact of Non-pharmaceutical Interventions on Ending Lockdowns

As many federal and state governments are starting to ease restrictions on non-pharmaceutical interventions (NPIs) used to flatten the curve, we developed an agent-based simulation to model the incidence of COVID-19 in King County, WA under several scenarios. While NPIs were effective in flattening the curve, any relaxation of social distancing strategies yielded a second wave. Even if daily confirmed cases dropped to one digit, daily incidence can peak again to 874 cases without import cases. Therefore, policy makers should be very cautious in reopening society.

The implication of using dominant hand to perform laryngoscopy: an analysis of the laryngoscopic view and blade-tooth distance

BACKGROUND: Existing laryngoscopes are designed to be handled by the left hand, whereas most healthcare professionals are right-handed. However, controlling the laryngoscope device requires considerable strength and refinement to control the blade. We examined the usefulness of a right-handed laryngoscope to validate its clinical applicability. METHODS: One hundred sixty-four patients for general anesthesia were involved. Laryngoscopy was performed twice for each patient, once using a conventional left-handed Macintosh No. 3 laryngoscope and once using a right-handed one, by 25 right-handed and 18 left-handed laryngoscopists. The perpendicular distance from the tip of the maxillary incisor to the flange of each blade was measured when the maximum visibility of the glottis was obtained. We compared the distances, chances of directly contacting the tooth, laryngoscopic views and subjective feeling of difficulty in handling device between the two laryngoscopes. RESULTS: For the right-handed laryngoscopists, distance varied significantly between the two laryngoscopes (5.0 ± 3.5 and 5.7 ± 3.7 mm [mean ± standard deviation] for the conventional and right-handed laryngoscopes, respectively [P < 0.001]). The right-handed laryngoscope was associated with a decreased chance of directly contacting the teeth (P = 0.001). Additionally, the right-handed laryngoscope provided a better view than the conventional one (P = 0.005). Conversely, most of the left-handed laryngoscopists felt that the procedure using a conventional laryngoscope was easier than with a right-handed one. CONCLUSIONS: When a right-handed laryngoscopist uses a right-handed laryngoscope, a better laryngoscopic view and a reduced chance of blade contact with the teeth can be achieved.

Intraoperative predictors of early tracheal extubation after living-donor liver transplantation / 대한마취과학회지

BACKGROUND: Prolonged mechanical ventilation after liver transplantation has been associated with deleterious clinical outcomes, so early tracheal extubation posttransplant is now increasing. However, there is no universal clinical criterion for predicting early extubation in living-donor liver transplantation (LDLT). We investigated specific predictors of early extubation after LDLT. METHODS: Perioperative data of adult patients undergoing LDLT were reviewed. "Early" extubation was defined as tracheal extubation in the operating room or intensive care unit (ICU) within 1 h posttransplant, and we divided patients into early extubation (EX) and non-EX groups. Potentially significant (P < 0.10) perioperative variables from univariate analyses were entered into multivariate logistic regression analyses. Individual cut-offs of the predictors were calculated by area under the receiver operating characteristic curve (AUC) analysis. RESULTS: Of 107 patients, 66 (61.7%) were extubated early after LDLT. Patients in the EX group showed shorter stays in the hospital and ICU and lower incidences of reoperation, infection, and vascular thrombosis. Preoperatively, model for end-stage liver disease score, lung disease, hepatic encephalopathy, ascites, and intraoperatively, surgical time, transfusion of packed red blood cell (PRBC), urine output, vasopressors, and last measured serum lactate were associated with early extubation (P < 0.05). After multivariate analysis, only PRBC transfusion of < or = 7.0 units and last serum lactate of < or = 8.2 mmol/L were selected as predictors of early extubation after LDLT (AUC 0.865). CONCLUSIONS: Intraoperative serum lactate and blood transfusion were predictors of posttransplant early extubation. Aggressive efforts to ameliorate intraoperative circulatory issues would facilitate successful early extubation after LDLT.

Butyrylcholinesterase deficiency identified by preoperative patient interview / 대한마취과학회지

No abstract available.

Perioperative risk factors for prolonged mechanical ventilation after liver transplantation due to acute liver failure / 대한마취과학회지

BACKGROUND: Acute liver failure (ALF) is a rapidly progressing and fatal disease for which liver transplantation (LT) is the only treatment. Posttransplant mechanical ventilation tends to be more prolonged in patients with ALF than in other LT patients. The present study examined the clinical effects of prolonged posttransplant mechanical ventilation (PMV), and identified risk factors for PMV following LT for ALF. METHODS: We reviewed data of patients undergoing LT for ALF between January 2005 and June 2011. After grouping patients according to administration of PMV (> or = 24 h), donor and recipient perioperative variables were compared between the groups with and without PMV. Potentially significant factors (P or = grade III), intraoperative blood pressure fluctuation, and oliguria (< 0.5 ml/kg/h) were independent risk factors for PMV. CONCLUSIONS: PMV was associated with deleterious outcomes. Besides care for known risk factors including hepatic encephalopathy, meticulous attention to managing intraoperative hemodynamic circulatory status is required to avoid PMV and improve the posttransplant prognosis in ALF patients.

Resolution of atrial fibrillation with induction of general anesthesia: A case report

Atrial fibrillation is one of the most common arrhythmias in everyday life, and it is responsible for substantial mortality and morbidity in the general population.When atrial fibrillation is first noticed and it persists for a long time, it will be more difficulty to control and it will recur more often.A 58-year old female patient was scheduled for surgery due to the increased size of an intracranial arteriovenous malformation.During the preparation of anesthesia, we noticed the presence of atrial fibrillation.After about 2 hours of sedation and consultation, we decide to proceed with the surgery. With the induction of anesthesia by using thiopental sodium, we observed the rapid conversion of atrial fibrillation to sinus tachycardia.During the maintenance of anesthesia, the patient showed normal sinus rhythm and the surgery was completed without complications.

The effects of callander modification of laryngoscopic blade on hemodynamic changes according to the degree of difficult airway / 대한마취과학회지

BACKGROUND: Laryngoscopy and tracheal intubation are known to have profound cardiovascular effects. The Callander modification of Macintosh blade is associated with greater field of laryngoscopic view and decreased risk of dental contact. The purpose of this study was to compare the hemodynamic responses to laryngoscopy and tracheal intubation according to the degree of difficult airway, and to evaluate the usefulness of Callander modification of Macintosh blade for attenuating the hemodynamic responses. METHODS: One hundred, forty-eight patients scheduled for elective surgery were divided into Easy group and Difficult group by Wilson's risk sum score. Laryngoscopy was performed using either an ordinary Macintosh No. 3 blade or the modified Macintosh blade. The modification consisted of reducing the height of the flange by partial removal, as described by Callander et al. Hemodynamic variables (systolic, diastolic, mean blood pressure, heart rate and rate pressure product) were noted before induction (baseline) and immediately after intubation. RESULTS: The hemodynamic changes after tracheal intubation in Difficult group were significantly greater than those in Easy group (P < 0.05). When using the modified blade, systolic, diastolic and mean blood pressure after tracheal intubation were lower than those using the conventional blade regardless of Wilson's risk sum score, but no statistical significances could be found. CONCLUSIONS: The hemodynamic changes after tracheal intubation increased as the degree of airway difficulty increased. Laryngoscopy with the Callander's modified blade did not reduce the degree of hemodynamic stimulation compared with the conventional Macintosh blade.