Risk factors for prolonged mechanical ventilation in children with transposition of the great arteries and intact ventricular septum that underwent primary arterial switch operation

Objective To explore the risk factors for prolonged mechanical ventilation in children with transposition of great arteries and intact ventricular septum who underwent arterial switch operation. Methods This study was a retrospective, single center study.One hundred and twenty patients with transposition of great arteries and intact ventricular septum who underwent primary arterial switch operation between January 2014 and December 2016 at Fuwai Hospital were eligible for this study.The data of patients from pediatric intensive care unit database and electronic medical records were collected.The data related to postoperative respiratory assist time were collected, including demographic data, preoperative diagnosis, intraoperative data, and postoperative recovery data.The patients were divided into 2 groups according to ventilation time which were prolonged mechanical ventilation group(ventilation time >72 hours) and non-prolonged mechanical ventilation group(ventilation time ≤72 hours). The data of 2 groups were analyzed by using single factor analysis, and the P≤0.2 factors were processed into Logistic regression analysis. Results Ninety-six patients were enrolled including 22 patients in prolonged ventilation group and 74 patients in non-prolonged mechanical ventilation group.No statistical significance was found in 2 groups in gender, age, weight, preoperative lactate, hemoglobin, use of prostaglandin E1, mechanical ventilation, cardiopulmonary time, aortic clamping time, the ratio of left ventricular pressure to right ventricular pressure, immediate postoperative plasma lactate, and vasoactive inotropic score.The weight and postoperative left atrial pressure were significantly different between 2 groups with P<0.2.Weight were (3.5±0.9) kg in prolonged mechanical ventilation group and (3.9±1.0) kg in non-prolonged mechanical ventilation group (P=0.117). Left atrial pressures were (7.9±1.9) mmHg(1 mmHg=0.133 kPa) in prolonged mechanical ventilation group and (6.7±2.0) mmHg in non-prolonged mechanical ventilation group(P=0.015). The weight and left atrial pressure were processed into Logistic regression analysis and the results revealed that high left atrial pressure was the risk factor for ventilation prolongation(OR=1.048, P=0.020). Respiratory assist time in prolonged and non-prolonged ventilation group was 112(80, 194) h and 26(17, 46) h, respectively; ICU time in prolonged and non-prolonged ventilation group was 10(1, 14) d and 4(3, 6) d, respectively; and all the differences were significant(all P=0.000). The number of death in each group was 1 with no significant difference(P=0.420). Conclusions High left atrial pressure is the risk factor for prolonged mechanical ventilation in children with transposition of great arteries and intact ventricular septum following primary arterial switch operation. Key words: Congenital heart defects; Transposition of great arteries and intact ventricular septum; Heart surgery; Arterial switch operation; Prolonged mechanical ventilation