Nicholas Chrimes (of Vortex fame) over at Monashanaesthesia has done a lovely little test of three BVM circuits during spontaneous ventilation and discusses the results in a blog post here. Given that a lot of EDs have given up on the reusable BVM and replaced it with the throwaway orange thing (the worst performer in this little test) we should all be carefully reconsidering how we provide pre-oxygenation in the spontaneously ventilating ED patient.
EMcrit readers and listeners will already be all over this thanks to Scott Weingart’s NODESAT paper and discussions on the same topic but I still see many people holding an orange BVM over a patient’s face, paying little attention to seal, thinking that they are providing 100% O2.
I have moved to one of three options for Pre-O2.
1. Hudson mask with reservoir bag (the ill-nicknamed non-rebreather mask) on >15L/min for the low risk patient with good lungs (very few patients),
2. As above with Nasal prong oxygen added in at 3L/min until induction, then >15L/min during the apnoeic time (for most patients)
3. CPAP on 100%O2 during spontaneous ventilation and a PEEP valve on the BVM for positive pressure ventilation after induction for patients with bad lungs.
I keep the BVM for the non-ventilating patient.
Thanks to George Own-The-Oxylog Douros for bringing Nick’s post to my attention.