Discussion

Pulmonary artery sling is commonly associated with complete tracheal rings leading to a ring-slings complex.^{Reference Du, Wang and Wang2} In patients who require tracheal repair or intracardiac procedures, median sternotomy and cardiopulmonary bypass supported is generally needed. We successfully repaired isolated pulmonary artery sling using left thoracotomy in four children without severe adverse events or residual left pulmonary artery stenosis. This method is beneficial as it meets cosmetic needs,^{Reference Yamoto, Fukumoto and Sekioka4} reduces psychological stress, and maintains nipple sensitivity.^{Reference Kenney and Obermeyer6}

Wilcox et al.^{Reference Wilcox, Hart and de Alarcon7} reported that airway growth was not observed in patients with long-segment tracheal stenosis. Du et al.^{Reference Du, Wang and Wang2} further found that patients who underwent pulmonary artery sling repair without concomitant tracheal intervention exhibited no significant changes in tracheal morphology. Moreover, some children experienced only minimal symptomatic improvement following pulmonary artery sling repair and ultimately required subsequent tracheal reconstruction. Left thoracotomy remains, in our experience, an acceptable alternative approach only in children with pulmonary artery sling who have no complete tracheal rings and a narrow-to-wide ratio exceeding 0.6.

Although our approach avoids cardiopulmonary bypass by utilising a left thoracotomy, robust bailout strategies, which are centred on rigorous patient selection and intraoperative safety, must be meticulously planned: 1) A comprehensive preoperative assessment, including echocardiography, chest CT scan, and bronchoscopy, should be performed prior to surgery. In patients with concomitant intracardiac defects or complete tracheal rings, median sternotomy with cardiopulmonary bypass remains the preferred strategy; 2) if right-sided single-lung ventilation with high inspired oxygen concentration (90–100%) fails to maintain haemodynamic or respiratory stability before operation, median sternotomy with cardiopulmonary bypass should be performed; 3) prior to clamping the left pulmonary artery and pulmonary trunk, the inspired oxygen concentration should be increased to 90–100%, and a “watchful waiting” period should be instituted. Conversion to median sternotomy with cardiopulmonary bypass should be promptly undertaken if this oxygenation adjustment proves insufficient to sustain circulatory or respiratory stability; or 4) a standby cardiopulmonary bypass circuit and perfusionists must be available throughout the entire operation. In selected cases where haemodynamic instability or unexpected bleeding arises, partial bypass, which is achieved via cannulation of the main pulmonary artery and descending aorta, may be considered as a rescue strategy.

In conclusion, for patients with isolated pulmonary artery sling without significant tracheal stenosis or intracardiac anomalies, left thoracotomy remains a viable surgical approach. Comprehensive preoperative assessment of tracheal anatomy can obviate the need for subsequent tracheal reoperation.