Efficacy of a hybrid technique of simultaneous videolaryngoscopy with flexible bronchoscopy in children with difficult direct laryngoscopy in the Pediatric Difficult Intubation Registry.

Children with difficult tracheal intubation are at increased risk of severe complications, including hypoxaemia and cardiac arrest. Increasing experience with the simultaneous use of videolaryngoscopy and flexible bronchoscopy (hybrid) in adults led us to hypothesise that this hybrid technique could be used safely and effectively in children under general anaesthesia. We reviewed observational data from the international Pediatric Difficult Intubation Registry from 2017 to 2021 to assess the safety and efficacy of hybrid tracheal intubation approaches in paediatric patients. In total, 140 patients who underwent 180 attempts at tracheal intubation with the hybrid technique were propensity score-matched 4:1 with 560 patients who underwent 800 attempts with a flexible bronchoscope. In the hybrid group, first attempt success was 70% (98/140) compared with 63% (352/560) in the flexible bronchoscope group (odds ratio (95%CI) 1.4 (0.9-2.1), p = 0.1). Eventual success rates in the matched groups were 90% (126/140) for hybrid vs. 89% (499/560) for flexible bronchoscope (1.1 (0.6-2.1), p = 0.8). Complication rates were similar in both groups (15% (28 complications in 182 attempts) hybrid; 13% (102 complications in 800 attempts) flexible bronchoscope, p = 0.3). The hybrid technique was more likely than flexible bronchoscopy to be used as a rescue technique following the failure of another technique (39% (55/140) vs. 25% (138/560), 2.1 (1.4-3.2) p < 0.001). While technically challenging, the hybrid technique has success rates similar to other advanced airway techniques, few complications and may be considered an alternative technique when developing an airway plan for paediatric patients whose tracheas are difficult to intubate under general anaesthesia.

Effect of the thromboxane A2-receptor antagonists, SQ 29,548 and SQ 28,668, on the pulmonary hypertensive response to endotoxemia in swine.

The effects of two selective thromboxane (Tx) A2 antagonists (SQ 29,548 and SQ 28,668) on endotoxin-induced pulmonary hypertension were determined in anesthetized pigs. SQ 29,548 (10 micrograms/kg/min, i.v., n = 6) or vehicle (n = 7) was infused from 15 min before until 60 min after an intravenous infusion of Salmonella enteritidis endotoxin (1.0 microgram/kg). Within 20 min, vehicle-treated animals developed an acute 350 +/- 25% increase in pulmonary vascular resistance (PVR) with a 43% survival rate. In the presence of SQ 29,548 this initial pulmonary vasoconstriction was absent and all animals survived. However, a delayed increase in PVR of 58 +/- 20% was detected. The primary manifestation of the increase in PVR was an increase in pulmonary arterial pressure. In a similar preparation, septicemia was produced by Escherichia coli endotoxin (0.5 microgram/kg, i.v.) and SQ 28,668 (3, 10, 30 or 100 micrograms/kg/min, i.v., n = 5-6 per dose level) and vehicle (n = 6) treatments were compared. SQ 28,668 doses of 30 and 100 micrograms/kg/min mitigated the early, but not late, increases in PVR. These data demonstrate that endotoxemia in pigs produces an initial TxA2-receptor-dependent vasoconstriction and also a more slowly developing pulmonary hypertension which is probably due to other mediators.

Myocardial protection: a safe cardioplegic catheter.

The administration of cold cardioplegic solution has contributed to the "safe" time allowable for performance of intricate cardiac procedures under ischemic arrest. A catheter has been designed that delivers a large bolus of solution quickly, ensures rapid arrest of cardiac function, and allows continuous perfusion during the procedure. It permits the safe escape of air on reestablishment of cardiac function. The catheter can be inserted and removed through a small aortotomy, thereby preventing undue trauma to a sclerotic or thickened aorta.