Assessment of mouth-to-mask ventilation in resuscitation of asphyxic newborn babies. A pilot study.

ABSTRACT

The aim of the study was to compare the effectiveness of mouth-to-mask ventilation (MM) in neonatal asphyxia with bag-and-mask ventilation (BM). A new mouth-to-mask infant resuscitation system was constructed. The study was performed in two university clinics with different resources. The KEM Hospital in Bombay was well equipped and neonatologists took part in all resuscitations; Muhimbili Medical Centre in Dar es Salaam was understaffed and had no physicians available at resuscitation. Therefore, different protocols had to be used. In Bombay, the study period was limited to 5 minutes. If needed, mask ventilation was then replaced by intubation. In Dar es Salaam, MM ventilation was continued for up to 10 minutes, the inspiratory pressure was adjusted to 30 cmH2O and the ventilation was slow (8-10 breaths/min). In Bombay, 30 babies were allocated to the BM and 24 to the MM groups. In Dar es Salaam 56 were in the BM and 64 in the MM groups. The results for term babies in Bombay and both term and pre-term babies in Dar es Salaam showed no significant differences between the two groups of treatment, as determined by Apgar score > or = 4 at 5 and 10 minutes, number of babies with their first gasp, heart rate > 130 beats/min or pulse oximeter values above 75%, all at 5 minutes. An Apgar score > or = 4 at 5 minutes was achieved in more than 75% of all infants, irrespective of treatment. The rates of early neonatal mortality and neonatal convulsions did not differ between the two methods of resuscitation. In Dar es Salaam, the low respiratory frequency used in both groups was associated with a slow increase in heart rate above 130 beats per min. This result indicates that further studies will be needed before such slow respiratory frequencies are used. We conclude that, if adequate training is provided and the respiratory frequency is kept within the normal range, MM ventilation is an alternative to assisted ventilation when no bag and mask is available. However, further studies are necessary, since this method has proved to be tiring and uncomfortable for the resuscitating health personnel.