Background: Several studies have suggested that boarding of ICU patients in the ED is associated with increased mortality. We hypothesized that establishing a program of specialized emergency critical care (ECC) nurses would improve mortality of ICU patients boarding in the ED.
Methods: This was a retrospective pre- and post-intervention cohort study using electronic health record data at an academic medical center. The pre-intervention period (10/2013-9/2014) consisted of usual care by ED nurses with a nurse:patient ratio of 1:2. In the post-intervention period (10/2015-9/2016), ICU patients in the ED were cared for by an ECC nurse in addition to the primary ED nurse. All adult ED patients who received an ICU admission order were included. Patients transferred to an outside facility directly from the ED were excluded. SOFA scores were calculated using the worst reported values from time of ED arrival up to 1-hour after ICU admission order (eccSOFA). Boarding time was defined as the time from ICU admission order to the time of ED departure, downgrade order, or death. The primary outcome was in-hospital mortality. Groups were compared using χ2
Results: There were no statistically significant differences between groups with respect to age, sex, co-morbidities, or illness severity. The proportion of patients who boarded for >6 hours almost doubled from 13.8% pre-intervention to 26.9% post-intervention (p<0.0001). In-hospital mortality in the pre-intervention group (N=1199) and the post-intervention group (N =1386) was the same (11.8%). Mortality of patients boarding >6 hours in the combined pre- and post-intervention groups was 9.5%. Surprisingly, mortality was higher for patients boarding ≤6 hours, which was 12.4%. (p=0.06). Mortality of severely ill patients (eccSOFA >5) boarding for >6 hours in the pre-intervention group was 19.4% and post-intervention was 17.8% (risk difference -1.6%, 95% CI -16.8% to 13.5%).
Conclusion: Contrary to previous reports, critically ill patients who boarded >6 hours did not have higher mortality than patients who boarded ≤6 hours. During the study period, the proportion of critically ill patients boarding in the ED for >6 hours increased dramatically, yet overall mortality remained the same. In the sickest subgroup of ICU patients boarding >6 hours in the post-intervention period, mortality was lower, although the difference was not statistically significant. These results suggest that ECC nurses may improve outcomes for severely ill ICU patients who board in the ED.