This study was conducted on neonates needing intubation; Group A,: the ETT insertion depth was estimated according to the OHL method. Group B,: the ETT insertion depth was estimated according to the 7-8-9 method.

Inclusion Criteria:

• • Full term and preterm neonates who were admitted to NICU and needing endotracheal intubation for invasive mechanical ventilation or administration of surfactant.

  • Delivery room intubations were not included as infants are not routinely weighed prior to resuscitation at our hospital. However, infants intubated in the delivery room who were subsequently intubated in the NICU were eligible for inclusion in our study.

Exclusion Criteria:

- 1. Major upper or lower airway anomalies. 2. Infants with craniofacial, vertebral anomalies. 3. Significant congenital anomalies including cardiac, abdominal or respiratory.

4. Neonates those whose parents declined consent were excluded from the study.