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Lung Volume Head Ratio: A Potential Parameter for Prediction of Respiratory Distress in Newborn
Shama Afreen1, Manisha Kumar2, Shushma Nangia3
1Department of Obstetrics and Gynecology, Lady Hardinge Medical College, New Delhi, India.
Objective:
This study aimed to evaluate the role of fetal lung biometry profile including fetal lung volume head ratio (LVHR) in predicting the occurrence of respiratory distress (RD) in early preterm newborn.
Study Design:
Prospective analytical cohort study was done to evaluate the clinical value of fetal sonographic measures, such as the total lung area (TLA), total lung volume (TLV), TLA head ratio (TLHR), LVHR, in pregnant women between 30 to 34 weeks' gestation who were expected to deliver within the next 72 hours. The cases with RD were compared with controls who had normal outcome.
Result:
A total of 30 (27.4%) out of 110 patients, who underwent early preterm delivery, with RD rest 80 (72.6%) were controls. The TLA was 694.1 ± 373.1 mm2 in cases whereas 1,149.0 ± 506 0.7 mm2 in controls with significant difference between the two groups (p < 0.001). Similarly the lung volume (p < 0.001) and the LVHR were significantly less (p < 0.001) in cases compared with controls. The TLV was a better parameter (sensitivity, 73.7% and specificity, 86.4%) compared with TLA (sensitivity, 68.4% and specificity, 81.5%). Among the lung head ratios, LVHR had the best sensitivity of 95.5%, specificity: 80.3%, positive predictive value (PPV): 58.3%, and negative predictive value (NPV): 97.0% at the cut-off of 46.5.
Conclusion:
RD was observed in nearly one-third of the preterm infants born between 30 and 34 weeks of gestation and could be predicted accurately in over 9 out of 10 cases using the novel parameter TLVR.
Key Points:
· Preterm newborn.. · Fetal lung volume.. · Respiratory distress..
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