Objectives To determine the feasibility of end tidal (EtCO₂) monitoring of preterm infants in the delivery room, to determine EtCO₂ levels during delivery room stabilisation, and to examine the incidence of normocapnia (5–8 kPa) on admission to the neonatal intensive care unit in the EtCO₂ monitored group compared with a historical cohort without EtCO₂ monitoring.

Patients and methods Preterm infants (<32 weeks) were eligible for inclusion in this observational study. The evolution of EtCO₂ values immediately after delivery was assessed and linear least-squares methods were used to fit a line to EtCO₂ recordings. The partial pressure of CO₂ in blood (PCO₂) from the infants who received EtCO₂ monitoring was compared with a historical cohort without EtCO₂ monitoring.

Results EtCO₂ monitoring was feasible in the delivery room. EtCO₂ values were successfully obtained in 39 (88.7%) of the 44 infants included in the study. EtCO₂ gradually increased over the first 4 min. Intubated infants had higher EtCO₂ values compared with infants who were not intubated, with median (IQR) values of 4.7 (3.3–8.4) kPa versus 3.2 (2.6–4.2) kPa (p=0.05). No difference was found between the proportions of PCO₂ values within the range of normocapnia among infants who received EtCO₂ monitoring compared with those who did not (56.8% vs 47.9%, p=0.396).

Conclusions Delivery room EtCO₂ monitoring is feasible and safe. EtCO₂ values obtained after birth reflect the establishment of functional residual capacity and effective ventilation. The potential short-term and long-term consequences of EtCO₂ monitoring should be established in randomised controlled trials.