Emergency physician use of end‐tidal oxygen monitoring for rapidsequence intubation

Abstract

Background End‐tidal oxygen (ETO 2 ) monitoring is used by anesthesiologists to quantify the efficacy of preoxygenation before intubation but is generally not used in emergency departments (EDs). We have previously published our findings describing preoxygenation practices in the ED during blinded use of ETO 2 . The purpose of this investigation is to determine whether the unblinded use of ETO 2 monitoring led to improvements in preoxygenation during rapid sequence intubation in the ED and also the oxygen device or technique changes that were used to achieve higher ETO 2 levels. Methods We conducted an interventional study at 2 academic EDs in Sydney, Australia and New York City, New York using ETO 2 monitoring to investigate the preoxygenation process and effectiveness. We used data collected during a previous descriptive study for the control group, in which care teams in the same 2 EDs were blinded to the ETO 2 value. In the study group, clinicians could utilize ETO 2 to improve preoxygenation. Following an education process, clinicians were able to choose the method of preoxygenation and the techniques required to attempt to achieve an ETO 2 level >85%. The primary outcome was the difference in ETO 2 levels at the time of induction between the control and study group and the secondary outcome included the methods that were attempted to improve preoxygenation. Results A convenience sample of 100 patients was enrolled in each group. The median ETO 2 level achieved at the time of induction was 80% (interquartile range 61 to 86, overall range 73) in the control group and 90% in the study group (interquartile range 83 to 92, overall range 41); the median difference was 12 (95% confidence interval: 8, 16, P = < 0.001). The majority of oxygen device changes were from non‐rebreather mask to bag‐valve‐mask (BVM) (15%, n = 15) and changes in technique from improvements in mask seal (54%, n = 34). The final device used in the study group was BVM in 87% of cases. Conclusions In 2 clinical studies of ETO 2 in academic EDs, we have demonstrated that the use of ETO 2 is feasible and associated with specific and potentially improved approaches to preoxygenation. A clinical trial is needed to further study the impact of ETO 2 on the preoxygenation process and the rate of hypoxemia.

Efficacy of preoxygenation with end-tidal oxygen when using different oxygen concentrations in patients undergoing general surgery: a single-center retrospective observational study

“…Although the EtO 2 is a ventilator parameter used in clinical practice, it is not monitored routinely (41). The importance of EtO 2 has been emphasized in emergency departments, wherein rapid sequence intubation is commonly performed (42,43); EtO 2 monitoring improved the quality of preoxygenation, resulting in a reduction in hypoxemic events during intubation (44). Adequate preoxygenation confirmed by EtO 2 monitoring will improve patient safety by checking for the presence of a leak and optimizing oxygen wash-in, which makes the induction of anesthesia more comfortable and relaxed.…”

Time to Renitrogenation After Maximal Denitrogenation in Healthy Volunteers in the Supine and Sitting Positions

“…Our results also highlight that rapid loss of preoxygenation adequacy, whether due to mask leak or suboptimal oxygen delivery, can occur prior to laryngoscopy in patients undergoing emergent RSI and that ETO 2 monitoring could measure this loss in real time. 35,36…”

Current Considerations in Emergency Airway Management

“…Though not currently widely available, end-tidal oxygen (ETO2M) monitoring has the potential to improve emergency airway care dramatically. Though use in the Emergency Department remains relatively uncommon, ETO2M is a tool considered feasible and has potentially significant benefits to preoxygenation [ 36 ]. These devices continuously monitor partial pressure of oxygen (PaO2), rather than pulse oximetry (SpO2).…”

“…With use of end-tidal oxygen monitoring, the provider could theoretically monitor (in real time) the evolution of the PaO2, rather than relying on the SpO2 alone. In the above example, the transition from hyperoxia to hypoxia could be anticipated earlier and more reproducibly [ 36 ].…”