When I saw the title of this new study I thought immediately this has to either be by Peter Davis or one or more of his disciples… former trainees, I mean. In fact it is both:
A two center trial from Melbourne and from Edmonton randomized 137 babies of under 34 weeks gestation who needed face mask ventilation in the delivery room. The idea was to determine if routine use of an oropharyngeal airway (OPA) would improve ventilation and therefore improve the efficacy of resuscitation, the primary outcome variable was therefore the presence of obstructed breaths, as seen on a respiratory function monitor during assisted ventilation via face mask in the delivery room.
The main finding is that airway obstruction was much more frequent with the use of the OPA, partial obstruction of at least one attempted inflation occurred 70% of the time with the OPA and 54% without. Complete obstruction was a little bit more frequent without the OPA, but overall proportion of babies havaing any kind of airway obstruction episodes was 80% with the OPA and 64% without.
This points out how frequent airway obstruction is during resuscitation of the preterm infant, even teams with an acute interest in the mechanics of resuscitation find a very high frequency of airway obstruction. The respiratory function monitor looks more and more like a good option for these babies, it is sometimes difficult to know how well you are ventilating a baby, with our current approach trying to avoid overlarge tidal volumes and too much chest movement.
A supplementary finding is that it is often difficult to insert the airway
An attempt was made to insert the OPA in all 67 infants randomized to the intervention, with difficulty experienced in 15 (22%); these were exclusively related to airway opening and inserting the OPA above and behind the tongue. The OPA had to be either down or upsized in these 15 infants. No trauma (bleeding from oropharynx) was seen. Gagging was observed in 6 (9%). During PPV, the OPA was dislodged (pushed out by the movements of the tongue) in 23 (34%) infants. Operators were either unable to insert the airway and maintain the airway in position to provide PPV or felt more comfortable to remove
the airway in order to continue PPV in 19 (28%) infants.
I don’t really think you should throw away the OPA, but they should clearly be kept in reserve for rare cases. Remember the “A” in “Mr SOPA” does not mean an OPA, it means either intubation or LMA.
(I made an error in the title of the previous version of this post, which was oropharyngeal masks for resuscitation… oops!)