Abstract:

Objective To explore the correlation between central venous oxygen saturation （ScvO₂）， blood lactate （Lac）， arterial oxygen saturation （SaO2） and mechanical ventilation time in infants with congenital heart disease （CHD）. Methods Eighty?four CHD children treated in the First People's Hospital of Zunyi were enrolled between January 2020 and December 2024. According to postoperative mechanical ventilation time， they were divided into prolongation group （28 cases， mechanical ventilation time ≥ 72 h） and non?prolongation group （56 cases， mechanical ventilation time < 72 h）. The clinical data， score of risk adjustment for congenital heart surgery （RACHS?1）， levels of ScvO₂， and Lac and SaO₂ in the two groups were compared. The risk factors of postoperative mechanical ventilation time were analyzed by multivariate logistic regression analysis， and predictive value of ScvO₂， Lac and SaO₂ for prolonged mechanical ventilation time was analyzed by ROC curves. The clinical outcomes in the two groups were recorded. Results There were significant differences in age， preoperative pneumonia， RACHS?1 grading， and levels of ScvO₂， Lac and SaO₂ among children with different mechanical ventilation time （P < 0.05）. Multivariate logistic regression analysis showed that ScvO₂， Lac and SaO₂ were independent influencing factors of postoperative mechanical ventilation time （P < 0.05）. ROC curves analysis showed that area under the curve （AUC） values of ScvO₂， Lac， SaO₂ and combined detection for predicting prolonged postoperative mechanical ventilation were 0.846， 0.863， 0.839 and 0.917， and the best cut?off values were 67.64%， 1.51mmol/L and 96.06%， respectively （P < 0.05）. The failure rate of weaning in the prolongation group was higher， and stay time in PICU and actual length of hospital stay were longer than those in non?prolongation group （P < 0.05）. Conclusion The levels of ScvO₂， Lac and SaO₂ are related to mechanical ventilation time in CHD infants. They are all independent risk factors affecting prolonged mechanical ventilation and can be applied as auxiliary detection indexes to predict the prolongation of mechanical ventilation in clinical practice.

Key words: infant, congenital heart disease, mechanical ventilation, central venous oxygen saturation, blood lactate, arterial oxygen saturation