Latency and loss of pulse oximetry signal with the use of digital probes during prehospital rapid-sequence intubation

Abstract

Background: Prehospital personnel rely on timely and accurate pulse oximetry data when performing critical skills, such as rapid-sequence intubation (RSI). However, loss of signal may be a frequent occurrence in patients with poor peripheral perfusion. In addition, a delay or latency period in the timeliness of pulse oximetry data may exist with probes placed on the fingers.

Objective: To define the incidence of pulse oximetry signal loss or a latent period during prehospital RSI.

Methods: Patients with severe traumatic brain injury (TBI) (Glasgow Coma Scale score [GCS] 3-8) undergoing prehospital RSI by air medical crews were enrolled. Data from hand-held oximetry-capnometry units were analyzed for either the loss of a pulse oximetry tracing (≥ 30 seconds) during the RSI procedure or the presence of a latent period, defined by the saturation of peripheral oxygen (SpO(2)) nadir occurring after intubation in patients undergoing desaturation (SpO(2) ≤ 93%) during the procedure.

Results: A total of 98 of 124 patients (79%, 95% confidence interval [CI] 71-85%) had pulse oximetry failure during critical points in the RSI procedure. In the 49 patients with a desaturation during RSI, a latent period was observed in 27 patients (55%, 95% CI 41-68%).

Conclusions: A high incidence of pulse oximetry failure was observed with the use of a digital pulse oximetry probe during prehospital RSI. In addition, a latent period appears to exist in the majority of patients undergoing desaturation.