Prevalence and risk factors for prolonged mechanical ventilation in patients with congenital heart diseases undergoing cardiac surgery at a tertiary care center.

Abstract

Objective: To determine the prevalence and risk factors for prolonged mechanical ventilation (PMV) in patients with CHDs undergoing cardiac surgery at a tertiary care center of Karachi, Pakistan. Study Design: Cross-sectional study. Setting: Paediatric Cardiac Intensive Care Unit (PCICU) at National Institute of Cardiovascular Diseases, Karachi, Pakistan. Period: July 2022 to June 2023. Material & Methods: We analyzed patients who underwent open or closed heart surgery for CHDs. PMV was defined as duration of mechanical ventilation > 72 hours from the time of arrival to PCICU until extubation after cardiac surgery. Peri-operative factors were noted and their association with PMV was documented. Results: In a total of 184 patients who underwent surgeries for CHD, 105 (57.1%) were male while the overall mean age was 7.23±6.49 years. Post-surgery, PMV was documented in 17 (9.2%) patients. PMV was significantly associated with age (p=0.001), weight (p<0.001), cyanosis (p=0.005), TAPSE (p=0.011), and CPB time (p=0.003). Post-surgery, PMV was linked with metabolic acidosis (p=0.003), lactate (p=0.001), AVDO2 (p<0.001), inotropic score (p=0.002), low cardiac output (p=0.005), LV dysfunction (p<0.001), acute kidney injury (p=0.002), sepsis (p<0.001), pneumonia (p=0.004), mortality (p=0.045), and PCICU stay (p<0.001). Conclusion: PMV was documented in 9.2% patients who underwent CHD repair. Age, weight, cyanosis, TAPSE, CPB time, metabolic acidosis, lactate, AVDO2, inotropic score, low cardiac output, LV dysfunction, acute kidney injury, sepsis, and pneumonia were noted to be significant risk factors for PMV.