Objective: The purpose of this study was to determine factors contributing to prolonged mechanical ventilation in children following surgery for congenital heart defects.
Design: Prospective cohort trial.
Setting: Critical Care Unit. "Ignacio Chávez" National Heart Institute, México; from January to December 2000.
Patients: A total of 318 consecutive patients < 18 years old who underwent cardiovascular surgical procedures for congenital heart defects were enrolled in this study. Of these, 297 patients were admitted to the intensive care unit with respiratory support and 2.8% required prolonged mechanical ventilation (MV) > 120 hours.
Measurements and main results: Patients with cardiac failure had MV time of 214 +/- 200 hours, whereas those without it had MV time of 33 +/- 73 hours (p > 0.001). Patients with severe pulmonary hypertension had MV time of 160 +/- 176 hours, while those who did not had MV time of 47 +/- 105 hours (p < 0.001). Twenty-four patients (8.5%) had extubation failure, in 79% them due to hemodynamic alteration during the respiratory support time of 277 +/- 188 hours versus the rest of the group with MV time of 41 +/- 92 hours (p < 0.001). Factors associated with prolonged MV (> 120 hours) were: patients ages of < 1 year, pulmonary hypertension, and cardiac failure, and represented the greatest risk (90%, CI 58 to 99) of prolonging MV. Mortality rate was 34% for patients with prolonged MV. Times of aortic clamping and cardiopulmonary bypass were not significant risk factors for prolonged respiratory support.
Conclusion: Patients ages of < 1 year old, pulmonary hypertension, and cardiac failure were significant risk factors for prolonged respiratory support.