Pushing Geographical Boundaries: Interfacility Transport and Remote ECMO Cannulation of Patients during COVID Pandemic

ABSTRACT

Purpose of study Due to the high incidence of ARDS in those with COVID-19, ECMO centers began utilizing this therapy in early phases of the pandemic. Although receiving care at a high volume ECMO center has been associated with improved mortality amongst this patient population, there are significant obstacles associated with providing this service to those residing far from such centers. Amidst a pandemic, these challenges are compounded. Our urban, academic medical center serves as one of the highest volume ECMO referral centers in the Southeastern United States;amidst the pandemic we expanded our geographical boundaries to provide aid to those in need. Authors sought to describe characteristics of patients transported, evaluate for potential predictors of treatment success and to review our remote cannulation training and process. Additionally to identify transport associated challenges and lessons learned. Methods: Retrospective case series of critically ill, adult patients (≥18 years of age) with laboratory-confirmed COVID-19 transported to our medical center by our ECMO transport team from March 24, 2020 through June 8, 2021. Our team examined age, gender, body mass index, ratio of arterial partial pressure to fractional inspired oxygen (P/F ratio);duration of mechanical ventilation, ECMO support and ICU admission. Descriptive statistics including mean, standard deviation, ranges, median, percentages and associated interquartile ranges (IQR) were used. Summary of results: 63 adult patients admitted to the Intensive Care Unit (ICU) with COVID associated ARDS requiring ECMO support were admitted to our ECMO center. The mean age of those transferred was 44 years old [SD 12;IQR 36-56] (Table 1). Fifty nine percent [n=37] of patients were male, fifty two percent [n=33] were African American, and the average body mass index (BMI) of our cohort was 39.7 [SD 11.3;IQR 31-48.5]. Medical history of hypertension and diabetes were commonly noted in forty six and twenty four percent of patients respectively (Table 1). All but one patient [n=62] required mechanical ventilation during their hospitalization. The majority of patients [77.8%;n=35] had severe ARDS -defined as P/F ratio less than 100-on transfer. Median days of admission and mechanical ventilation at the time of ECMO initiation were 8 days [IQR 5-12] and 4 days [IQR 2-6] respectively. Majority of patients [92% n=58] were transferred from facilities outside of our healthcare system and via ambulance [98.3% n=57]. Amidst those, eighty seven percent [n=55] were remotely cannulated (Table 2). Transport distances ranged from 2.2 to 236 miles [median 22.5 miles;IQR 8.3-79] and round trip transport times-not including time for pre cannulation preparation, cannulation, initiation of ECMO support and preparing patients for transport-ranged from 18 to 476 minutes [median 83 min;IQR 44-194]. Median duration of ECMO support was 17 days [IQR 9.5-34.5]. Duration of mechanical ventilator support was a median of 24 days [IQR 14-34]. Length of stay in the intensive care unit (ICU) [median 36 days;IQR 17-49] and hospital [median 39 days;IQR 25-57] varied. Amongst those discharged thus far, sixty percent survived [n=31]. Twenty nine percent percent [n=10] were discharged to their homes, fifty three percent [n=18] to rehabilitation facilities and nine percent [n=3] were back to the referral medical centers for continuation of care once they were determined to no longer have need for ECMO or transplantation. The majority of factors evaluated were not found to be statistically significant predictors of treatment success. Although ICU and hospital duration were noted to have p-values of significance, the associated odds ratios and small sample size make true clinical significance difficult to interpret.