Observed to expected lung area to head circumference ratio at different gestational ages with various measurements in predicting indication for extracorporeal membrane oxygenation in fetuses with isolated left-sided congenital diaphragmatic hernia / 中华围产医学杂志

ABSTRACT

Objective:To investigate the prediction value of observed to expected lung area to head circumference ratio (o/e LHR), measured at different gestational age with various methods, on indication for extracorporeal membrane oxygenation (ECMO) in fetuses with isolated left-sided congenital diaphragmatic hernia (CDH).Methods:Clinical data of 40 neonates who were diagnosed with left-sided CDH and treated in Guangzhou Women and Children's Medical Center were retrospectively collected from January 2017 to May 2021. The o/e LHRs were prenatally calculated using maximum diameter and tracing method at 22-24 and 31-33 weeks of gestation. According to whether the neonates had indications for ECMO after birth or not, they were divided into ECMO ( n=12) or non-ECMO group ( n=28). Differences in the o/e LHR and general situations between the two groups were analyzed using C hi-square test, independent sample t-test, and non-parametric Mann-Whitney U test. Binary logistic regression was used to analyze the influencing factors for ECMO requirement and receiver operating characteristic (ROC) curve was used to evaluate the value of o/e LHR in predicting the indication for ECMO. Results:Both maximum diameter and tracing method suggested that the o/e LHR at 31-33 gestational weeks was lower than that at 22-24 gestational weeks [maximun diameter method: 40.4 (32.9-51.5) vs 45.1 (36.3-53.4), Z=－2.48, P=0.013; tracing method: 38.6 (33.2-47.6) vs 44.1 (35.9-51.7), Z=－3.29, P=0.001]. There was no statistical difference in o/e LHR detected at the same gestational weeks between the two methods (both P>0.05). Binary logistic regression showed that o/e LHR measured at 31-33 gestational weeks using maximum diameter method was an independent protective factor for ECMO requirement ( OR=0.873, 95% CI 0.790-0.965, P=0.008). ROC curve analysis showed that the area under the curve for evaluating the predictive value of o/e LHR for ECMO requirement was 0.830 with the sensitivity of 83.3% and the specificity of 71.4% when the cut-off value of o/e LHR at 31-33 gestational weeks was 38.195 measured by maximum diameter method. Conclusions:The o/e LHR measured at 31-33 weeks is lower than that at 22-24 weeks of gestation by both methods. The o/e LHR measured by maximum diameter method at 31-33 weeks of gestation may be useful for predicting the ECMO indication after birth but requiring comprehensive evaluation of clinical conditions due to its insufficient predicting power.