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Updated: Feb 5, 2026

Point-of-Care Ultrasound: A Review of Ultrasound Parameters for Predicting Difficult Airways
Published on: April 7, 2023
Prenatal Prediction of Difficult Intubation in Periviable Neonates Using Standard Fetal Biometric Parameters
Tara A Lynch1, J Christopher Glantz1, Kathryn Drennan1
1Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Rochester Medical Center, Rochester, New York.
Objective:
To assess whether standard fetal biometric parameters can be used to predict difficult intubations in periviable neonates undergoing resuscitation.
Study Design:
This is a retrospective case-control study of periviable neonates delivered at 23 to 256/7 weeks at an academic hospital during a 5-year period in whom intubation was attempted. Standard fetal biometric measurements were included if they were taken within 7 days of delivery. Primary outcome was intubation in one attempt and was compared with more than one attempt. Data were also collected for fetal gestational age at delivery, neonatal birth weight, estimated fetal weight, head circumference, biparietal diameter, and abdominal circumference. Parametric and nonparametric statistical tests used p < 0.05 as significant.
Results:
In total, 93 neonates met the inclusion criteria. The mean estimated fetal weight was 675 g (standard deviation [SD] ± 140), and the mean neonatal birth weight was 706 g (SD ± 151). The median interval between fetal ultrasound and delivery was 3 days (range: 0-7 days). A total of 45 neonates (48.3%) required more than one intubation attempt. The median number of intubation attempts was 1 (range: 1-10). There was no association between intubation difficulty and fetal abdominal circumference, biparietal diameter, head circumference, gestational age, estimated fetal weight, and neonatal birth weight (all p > 0.05).
Conclusion:
Standard biometry in periviable neonates does not predict intubation difficulty.
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