The COVID-19 Army Rapid Assessment Tool (CARAT) for Management of COVID-19 in the Deployed Setting

The COVID-19 pandemic poses unique challenges within the austere clinical setting, and the time between patient presentation and deterioration is a critical opportunity for intervention. In some cases, this may be a life-saving transfer to a higher level of care. US Central Command (CENTCOM) has provided valuable guidance for COVID-19 management in the operational environment,1 and has proposed the National Early Warning System 2 (NEWS2) scoring tool as a useful adjunct to gauging illness severity. NEWS2, however, does not consider co-morbidities, such as diabetes or chronic cardiac disease, which could worsen the clinical course of SARS-CoV-2 patients. Thus, NEWS2 fails to address such factors during the risk stratification of patients to a higher level of care. To address this concern, June 2020, 3rd Medical Brigade, Operation Spartan Shield (OSS) developed the COVID-19 Army Rapid Assessment Tool (CARAT) with inputs from clinicians and researchers (The Team). The CARAT is a clinical scoring system, modified from the NEWS2, which combines the effects of co-morbid disease with the current physiological condition of a COVID-19 patient. The Team obtained clinical data for 105 patients from the CENTCOM area of responsibility (AOR), who presented to a military treatment facility (MTF) symptomatic for, and testing positive for SARS-CoV-2, during the time period of June to mid-August 2020. Each patient was retrospectively assigned a CARAT score based on his or her initial presentation. Preliminary review of data suggested a CARAT value of 4 or greater was an indicator for risk of further deterioration. Patients were then grouped into two categories: patients who received transfer to a higher level of care, versus "stay-in-place" supportive care. Results showed that 100% of patients with a score ≥4 had been transferred to a higher echelon of care, compared to 2% of patients with scores less than 4. A Fisher's exact test demonstrated a statistically significant difference between these two groups (p is less than 0.001). Interestingly, when compared with the NEWS2 score, the CARAT identified 9 individuals for transfer to a higher level of care, of whom only one patient was identified by the NEWS2, clearly underscoring the significance of CARAT despite small sample size. We therefore recommend that CARAT be further validated in predicting disease severity and need for emergent evacuation in larger patient settings.