I’ve been a convert to use of ETCO2 monitoring for not just anaesthesia in the OT or ED, but also for procedural sedation. This is driven in part by results of the NAP4 audit and also from colleagues in the FOAMed world. Perhaps I am over cautious, but my use of ETCO2 extends to monitoring of the sedated psych patient, for whom I consider administration of agents such as IV midazolam (or occasionally ketamine) once olanzapine wafers have failed, to be a standard of care.
So I was surprised by the statement over at EMTrends.org suggesting “no benefit to routine capnography in procedural sedation”. You can read a summary of the paper here or look up the reference in Anaesthesia & Analgesia (2014) 119(1) 49-55.
This paper looks at patients undergoing minor gynae procedures by non-anaesthetists in a Dutch hospital. Interestingly NONE received supplemental oxygen (despite being administered propofol). The authors state that the incidence of hypoxaemic incidents in the 206 patients with ETCO2 monitoring was not significantly better the 209 patients for whom ETCO2 was not used.
Fair enough – until you look at the rate of hypoxaemia (SpO2 < 91%) in both groups:
25.7% with capnography
vs
24.9 without capnography
That is pretty poor IMHO.
For the record, I think I will continue to advocate for :
– routine use of supplemental oxygen if using neuroleptics
– routine use of capnography
You can read more about ETCO2 here – as my friend Casey Parker of BroomeDocs says “It gives you A-B-C in one squiggly line”
I wouldn’t suggest throwing it away. I am just not sure its the panacea that everyone first thought it was going to be. The small hospital I work at doesn’t have ETCO2 in the ER but I wouldn’t go stopping our docs from doing sedation just for that reason.