Assessment of chest rise during mask ventilation of preterm infants in the delivery room

Background: Current neonatal resuscitation guidelines recommend using visual assessment of chest wall movements to guide the choice of inflating pressure during positive pressure ventilation (PPV) in the delivery room. The accuracy of this assessment has not been tested. We compared the assessment of chest rise made by observers standing at the infants' head and at the infants' side with measurements of tidal volume.

Methods: Airway pressures and expiratory tidal volume (V(Te)) were measured during neonatal resuscitation using a respiratory function monitor. After 60s of PPV, resuscitators standing at the infants' head (head view) and at the side of the infant (side view) were asked to assess chest rise and estimate V(Te). These estimates were compared with V(Te) measurements taken during the previous 30s.

Result: We studied 20 infants who received a mean (SD) of 23 (4) inflations during the 30s. Some observer felt unable to assess chest rise both from the head view (6/20) and from the side view (3/20). Observers from both head and side tended to underestimate tidal volume by 3.5mL and 3.3mL respectively. Agreement between clinical assessment and measured V(Te) was generally poor.

Conclusion: During mask ventilation, resuscitators were unable to accurately assess chest wall movement visually from either head or side view.