Electronic Medical Record-Based Pager Notification Reduces Excess Oxygen Exposure in Mechanically Ventilated Subjects

Abstract

BACKGROUND:

Liberal oxygenation during mechanical ventilation is harmful in critically ill patients and in certain subsets of patients, including those with stroke, acute myocardial infarction, and cardiac arrest. Surveillance through electronic medical records improves safety of mechanical ventilation in the ICU. To date, this practice has not been used for oxygen titration ( ${\mathbf{\text{F}}}_{{\mathbf{\text{IO}}}_{\mathbf{\text{2}}}}$ ) in adults. We hypothesize that a surveillance system based on the electronic medical record to alert respiratory therapists to titrate ${\mathbf{\text{F}}}_{{\mathbf{\text{IO}}}_{\mathbf{\text{2}}}}$ is feasible, safe, and efficacious.

METHODS:

In this pilot study, mechanically ventilated subjects were randomized to respiratory therapist-driven ${\mathbf{\text{F}}}_{{\mathbf{\text{IO}}}_{\mathbf{\text{2}}}}$ titration after an electronic alert versus standard of care (ie, titration based on physician order). An automated surveillance system utilizing a hyperoxemia-detection algorithm generated an electronic alert to a respiratory therapist’s pager. Hyperoxemia was defined as ${\mathbf{\text{F}}}_{{\mathbf{\text{IO}}}_{\mathbf{\text{2}}}}$ > 0.5 and ${\mathbf{\text{S}}}_{{\mathbf{\text{pO}}}_{\mathbf{\text{2}}}}$ > 95% for > 30 min. No other aspects of treatment were changed. We assessed feasibility, safety, and preliminary efficacy. Primary outcome was duration of hyperoxemia during mechanical ventilation. An unsafe outcome was identified as hypoxemia ( ${\mathbf{\text{S}}}_{{\mathbf{\text{pO}}}_{\mathbf{\text{2}}}}$ < 88%) within 1 h after titration per alert. Feasibility was assessed by a survey of respiratory therapists.

RESULTS:

Of 226 randomized subjects, 31 were excluded (eg, programming errors of the electronic alerts, no consent, physician discretion). We included 195 subjects, of whom 86 were in the intervention arm. Alert accuracy was 78%, and respiratory therapists responded to 64% of the alerts. During mechanical ventilation, exposure to hyperoxemia significantly decreased in the intervention group (median 13.5 h [interquartile range 6.2–29.4] vs 18.8 h [interquartile range 9.6–37.4]). No episodes of significant hypoxemia were registered. Most respiratory therapists agreed that the alert was helpful in reducing excessive oxygen exposure.

CONCLUSIONS:

Use of an electronic surveillance system to titrate ${\mathbf{\text{F}}}_{{\mathbf{\text{IO}}}_{\mathbf{\text{2}}}}$ was safe and feasible and showed preliminary efficacy in reducing hyperoxemia. Our study serves to justify larger randomized controlled trials for ${\mathbf{\text{F}}}_{{\mathbf{\text{IO}}}_{\mathbf{\text{2}}}}$ titration.