Pediatric Anesthesia最新文献

Remimazolam is a novel ultrashort-acting benzodiazepine, which like midazolam, results in sedation, anxiolysis, and amnesia through its agonistic effects on the gamma-amino butyric acid A receptor. As opposed to midazolam, its unique metabolism is via tissue esterases, which results in a rapid elimination with a limited context sensitive half-life and prompt dissipation of its effect when administration is discontinued. Remimazolam received FDA approval for use in adults in 2020. In preliminary and initial clinical trials, its efficacy and safety has been suggested in the adult population, both as a primary agent for procedural sedation or as an adjunct to general anesthesia. There are limited data regarding the use of remimazolam in infants and children and its use in this population remains off label as it does not hold FDA-approval in pediatric-aged patients. This narrative outlines the pharmacologic properties of this unique medication, reviews previous published reports of its role in pediatric-aged patients, and discusses dosing parameters and clinical use in this population.

Introduction: Bronchial blocker balloons inflated with small volumes of air increase balloon pressure, involving a risk of airway injury especially in young children. However, there are no established guidelines regarding the appropriate volumes of air required to provide safe bronchial occlusion.

Methods: This study aimed to introduce a novel method for calculating the amount of air required for safe bronchial blocker balloon occlusion for one lung anesthesia in young children. We included 79 pediatric patients who underwent video-assisted thoracoscopic surgery at our hospital. Preoperatively, the balloon pressure and corresponding diameter of 5F bronchial blockers inflated with different volumes of air were measured. Intraoperatively, bronchial diameters measured by computerized tomographic scans were matched to the ex vivo measured balloon diameters. The quality of lung isolation, incidence of balloon repositioning, and airway injury were documented. Postoperatively, airway injury was evaluated through fiberoptic bronchoscopy.

Results: Balloon pressure and balloon diameter showed linear and nonlinear correlations with volume, respectively. The median lengths of the right and left mainstem bronchi were median (interquartile range) range: 5.3 mm (4.5-6.3) 2.7-8.15 and 21.8 (19.6-23.4) 14-29, respectively. Occluding the left mainstem bronchus required <1 mL of air, with a balloon pressure of 27 cm H₂O. The isolation quality was high with no case of mucosal injury or displacement. Occluding the right mainstem bronchus required a median air volume of 1.3 mL, with a median balloon pressure of 44 cm H₂O. One patient had poor lung isolation due to a tracheal bronchus and another developed mild and transient airway injury.

Conclusion: The bronchial blocker cuff should be regarded as a high-pressure balloon. We introduced a new concept for safe bronchial blocker balloon occlusion for one-lung ventilation in small children.

Background: High-flow nasal oxygenation is reported to prolong duration of apnea while maintaining adequate oxygen saturation with the mouth closed. Also, buccal oxygenation is known to have similar effects in obese adults. We compared the effect of these two methods on prolongation of acceptable apnea time in pediatric patients with their mouth open.

Methods: Thirty-eight patients, aged 0-10 years were randomly allocated to either the high-flow nasal oxygenation group (n = 17) or the buccal oxygenation group (n = 21). After induction of anesthesia including neuromuscular blockade, manual ventilation was initiated until the expiratory oxygen concentration reached 90%. Subsequently, ventilation was paused, and the patient's head was extended, and mouth was opened. The HFNO group received 2 L·min^-1·kg^-1 of oxygen, and the BO group received 0.5 L·min^-1·kg^-1 of oxygen. We set a target apnea time according to previous literature. When the apnea time reached the target, we defined the case as "success" in prolongation of safe apnea time and resumed ventilation. When the pulse oximetry decreased to 92% before the target apnea time, it was recorded as "failure" and rescue ventilation was given.

Results: The success rate of safe apnea prolongation was 100% in the high-flow nasal oxygenation group compared to 76% in the buccal oxygenation group (p = .04). Oxygen reserve index, end-tidal or transcutaneous carbon dioxide partial pressure, and pulse oximetry did not differ between groups.

Conclusion: High-flow nasal oxygenation is effective in maintaining appropriate arterial oxygen saturation during apnea even in children with their mouth open and is superior to buccal oxygenation. Buccal oxygenation may be a good alternative when high-flow nasal oxygenation is not available.