Apneic Oxygenation during RSI
Sakles et al. First Pass Success Without Hypoxemia Is Increased With the Use of Apneic Oxygenation During Rapid Sequence Intubation in the Emergency Department. Academic Emergency Medicine 2016;23:703–710
Apneic oxygenation prior to intubation is know increase the patient’s oxygen reserves, therefore delaying hypoxemia, and its use during RSI intubations in the ED will correlate to a lower incidence of hypoxia.
A prospective analysis of patients intubated by emergency medicine residents in a single-center academic ED over a two-year period. EM residents were “strongly encouraged” to use apneic oxygen on patients undergoing RSI (not required by protocol). The recommended technique was placement of nasal cannula at 15 L/min in addition to non-rebreather mask at 15 L/min for at least 3 minutes. Data was collected via a form the intubating resident filled out after the procedure. The pre-oxygenation cohort included patients who received anywhere between 5-15 LPM. The primary outcome was first-pass success without any hypoxemia (SpO2 <90%).
Over two years 635 patients were included. First-pass success without hypoxemia was observed in 82.1% of patients (312/380) in the apneic oxygenation group and 69% (176/255) in the no apneic oxygenation group. The odds ratio was 2.2 (use of oxygenation with first pass success without hypoxemia).
Not placebo-controlled or randomized; more difficult airways in the non-oxygen cohort which may have skewed data. Certain situations or difficult airways may not have allowed time for pre-oxygenation and residents may have been more likely to use pre-oxygenation in more relatively stable patients. Although it should be noted that patients who were hypoxic prior to intubation were excluded. More “skilled and conscientious” residents may have used this technique more routinely. Initially, only a small percentage of residents were using apneic oxygenation, although this changed over the study. The reported data was self-reported from recollection and may have been unreliable – prior studies have shown that adverse events during intubation tend to be under-reported. Finally, several patients were excluded due to missing oxygen saturation.
The Bottom Line:
We know from prior research that multiple intubation attempts during RSI, which is associated with an increased risk of adverse events, is dangerous for patients. Desaturation during intubation is a common reason physicians abort an intubation attempt in order to “bag” the patient and increase oxygenation before trying again. Although the clinical significance of transient hypoxemia during RSI intubation is unknown, hypoxemia in early illness has been linked to poor outcomes. The use of apneic oxygenation prior to RSI is a safe, easy, non-invasive method to decrease the risk of hypoxia during intubation. Whenever possible, this technique should be a routine part of RSI in the ED. However, we also know that prolonged unnecessary exposure to 100% FiO2 oxygen is toxic to the lungs so don’t forget to take out the nasal cannula after the tube is in!