2024 FSA Podium and Poster Abstracts

P063: THORACOSCOPIC RESECTION OF CONGENITAL PULMONARY ADENOMATOID MALFORMATION COMPLICATED BY COMPROMISED LUNG ISOLATION
Sandy Ren, MD; Cameron Lambert; Shefali Mehta; University of Miami Health System / Jackson Memorial Hospital

Introduction/Background: Congenital pulmonary adenomatoid malformation (CPAM) is a bronchopulmonary anomaly characterized by excessive bronchi proliferation lacking normal alveolar development and has an incidence of 1/20,000 – 1/30,000 live births, accounting for 25% of all congenital lung anomalies. Symptomatic patients require surgical treatment, with lobectomy as the gold standard. Given the pulmonary malformation, the anesthetic management of CPAM resections can be challenging, with concerns of sudden hemodynamic collapse during lobectomy/cystectomy. We present the case of a CPAM resection complicated by an intraoperative event of sudden rise in end tidal carbon dioxide on capnography.

Case Presentation: A six-month-old, 5.45kg girl with left upper lobe CPAM underwent video assisted thoracoscopic surgery (VATS) for left upper lobectomy. Preoperative chest computed tomography scan with contrast showed a large air-filled cystic formation over the left upper lobe. Preoperative transthoracic echocardiogram revealed a persistent patent foramen ovale with trivial left-to-right shunting and a small aortopulmonary collateral, possibly supplying the CPAM. Physical exam was unremarkable prior to the surgery, and the patient proceeded to the operating room. General anesthesia was induced via inhalational induction, two large-bore peripheral intravenous lines were obtained, intubation achieved with a 3.5 cuffed endotracheal tube, an ultrasound-guided arterial line was obtained, and lung isolation was achieved under bronchoscopy via intentional mainstem intubation to right main bronchus. The pediatric surgeon proceeded with VATS, confirming adequate lung isolation, and the case proceeded without complications until the left upper lobe bronchus was transected. Immediately after, capnography revealed end tidal carbon dioxide rising sharply from thirties to over 100mmHg. The surgical team was immediately informed of the physiologic change and suspicion of insufflation entering the bronchial system, the ventilator settings were increased to 100% FiO2 with high flow rate, and the patient stayed hemodynamically stable throughout. An airleak from the distal end of the staple line was quickly identified and reinforced with clips with rapid improvement in end-tidal capnography to normal values. The remainder of the case proceeded and concluded with a left upper lobectomy and left thoracostomy tube placement. The patient was extubated and transported uneventfully to the pediatric intensive care unit (PICU) with the chest tube to water seal.

Discussion/Conclusion: Albeit rare, CPAM is an entity that pediatric anesthesiologists must be ready to provide care for in the operating room, often requiring multiple large-bore venous lines, beat-to-beat blood pressure monitoring, and lung isolation in the setting of VATS surgery. While we were able to successfully achieve lung isolation in the beginning of the case, confirmed by both bronchoscopy and laparoscopy, the sudden rise in capnography upon transection of the left upper lobe bronchus suggests the lung isolation became inadequate, allowing carbon dioxide insufflation to enter the ventilated pulmonary tree. Fortunately, the surgeon was able to quickly repair the leak with adequate visualization and the patient did not face hemodynamic derangements. This case highlights the difficulty of maintaining one lung ventilation among small airways and could possibly have been improved with a lung isolation assist device such as a balloon-tipped bronchial blocker.