O2047: Emergency CICU Transfers in Pediatric Cardiology: A Single Center Propensity Score-Matched Study

Background: Cardiorespiratory arrest is rare in the pediatric population. Researchers have identified a proxy metric in emergency transfers, defined as transfers to the intensive care unit requiring an emergent intervention (initiation of vasoactive medications, intubation, or large volume fluid bolus) within one hour of arrival. Emergency transfers in the general pediatric population transferred to the pediatric intensive care units are associated with worse outcomes including an increased mortality rate. Yet, there are limited published data describing this metric in the pediatric cardiology population. We aimed to assess the frequency of emergency transfers in the pediatric cardiology population from the cardiac acute care unit (CACU) to the cardiac intensive care unit (CICU) and the associated rates of mortality and post transfer CICU and hospital length of stay (LOS).

Methods: This is a single center retrospective cohort study with case control propensity score matching. We identified patients transferred from the CACU to the CICU between February 2019 to November 2023. We then performed propensity score matching assessing the likelihood of the primary outcome, in-hospital mortality, to match emergency to non-emergency transfers. We matched on the following variables: age, surgical status, diagnosis, presence of a high-risk diagnosis, reason for transfer, shift of transfer (weekday, weeknight, and weekend shift), quarter of year and pre-transfer LOS. After propensity scoring, 63 emergency transfers to 189 non-emergency transfers. Statistical analysis used Pearson’s Chi-squared test (Fisher’s exact when applicable) and Wilcoxon rank sum test for categorical and continuous variables respectively. This study used Standardized Mean Differences (SMD) to assess if the matching was successful.

Results: A total of 617 transfers were analyzed, 75 of which were emergency transfers (12%). Out of all the transfers, 53 (9%) had in-hospital mortality. On further analysis, 16 (21%) of emergency transfers and 37 (7%) of non-emergency transfers had an in-hospital mortality. In the unmatched data, there was statistically significant differences in mortality (p < 0.001), ICU LOS (12.82 days vs 4.61, p< 0.001), post ICU transfer LOS (38.7 vs 19.6, p=0.002). After successful matching, mortality was no longer statistically significant (21% vs 11%, p=0.055), but ICU LOS (12.88 vs. 4.58, p< 0.001) and post ICU transfer LOS (40 vs 19.2, p = 0.009) remained statistically significant.

Conclusion: This study demonstrates that emergency transfers are associated with significantly increased CICU and hospital LOS. Before propensity score matching, we found a significantly increased mortality rate in patients undergoing emergency transfer. After matching, the difference was no longer statistically significant. This may be related to the high acuity of the CACU patients. The increased healthcare resource utilization associated with emergency transfers suggests that this is an important marker to monitor and could be a target metric in future quality improvement studies.