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.