A depression of respiratory function following the cardiopulmonary bypass in infants and children
Fukasawa, M.; Orita, H.; Iijima, Y.; Goto, S.; Washio, M.
Kyobu Geka. Japanese Journal of Thoracic Surgery 46(4): 313-318
1993
ISSN/ISBN: 0021-5252 PMID: 8468854 Document Number: 408095
Fourty-one patients (2-44 month old) underwent the closure of ventricular septal defect using moderate-hypothermic cardiopulmonary bypass (CPB). The respiratory index (RI) were monitored after CPB, as functional parameters of oxygenation capacity. At 15 min after CPB, there was the increased level in RI (2.22 +/- 0.45; normal value: 0.1-0.37). Thereafter, RI gradually decreased by 90 min after CPB (1.22 +/- 0.19), and again increased reaching peak levels by 12 hrs after ICU-entry (2.56 +/- 0.64). The patients who exceed 1.00 at 15 min after CPB (RI-15) remained higher levels in RI compared to less than 1.00 and had the prolonged controlled ventilation. The RI-15 correlated with pulmonary-systemic flow ratio (Qp/Qs) and pulmonary-left ventricular pressure ratio (PA/LV). There was no significant correlation between RI-15 and CPB factors including CPB time, dilution rate, rectal temperature, flow and perfusion pressure. These results suggest that pulmonary dysfunction following the CPB may not be simply occurred by CPB but also involved by preoperative conditions. An increased pulmonary blood flow might be one of important and predictive factor for the depression of oxygenation following the cardiac surgery in infants and children.