The use of apneic oxygenation – so-called NODESAT – has been gaining rapidly in popularity. Curiously enough, however, its continued promotion occurs in the absence of high-quality evidence for benefit.
This most recent study is a prospective, observational evaluation of two years’ worth of intubation procedural outcomes. Patients receiving passive oxygenation during intubation were compared with those who did not, with the primary outcome being hypoxia (O2 saturation <90%) on the first-pass of intubation. During this time period, the use of apneic oxygenation was explicitly encouraged as a quality improvement initiative. Of the 1,140 intubations during this time period, 635 patients were included for analysis; 380 utilized apneic oxygenation and 255 did not. The apneic oxygenation cohort had a 17.9% incidence of hypoxia on the first intubation attempt, compared with 31.0% without. The authors conclude their observational data favors apnea oxygenation, and may improve safety.
This is a reasonable conclusion, to be certain. There were, of course, massive confounders regarding the two cohorts – and the largest predictor of hypoxia was not apneic oxygenation or technical factors, but simply whether the baseline oxygen saturation was >93%. An observational study, particularly one excluding 20% of potentially eligible patients due to incomplete data, simply continues to serve as hypothesis-generating for definitive evaluation.
I am not opposed to the use of apneic oxygenation, but it is reasonable to be realistic about the underlying evidence and not to behave dogmatically regarding its use. There are probably a few acute procedural delays associated with its use, but any patient-oriented harms or benefits would seem to be rather difficult to detect.
Other notes:
- LITFL publishes a lovely synopsis on the topic here.
- Yes, I’m about four months late to the party on this article – having missed the electronic publication back in February!
“First Pass Success Without Hypoxemia Is Increased With the Use of Apneic Oxygenation During Rapid Sequence Intubation in the Emergency Department”
http://www.ncbi.nlm.nih.gov/pubmed/26836712
If nothing else, I think NODESAT helps separate the true hypoxia from the "I just let the intern do DL too long"
are you kidding ?
Can't let our passions overstate the evidence. Perhaps there are no delays/harms/tangles from setting up the apneic O2. Perhaps these observational studies are confounded enough that the time-to-intubation rarely benefits from apneic O2. Either way, I expect – sort of like EtCO2 in sedation – that it's _really hard_ to find a difference in actual patient-oriented morbidity or mortality.