Assistance time and peripheral oxygen saturation in prehospital emergency data as predictors of COVID19 hospital outcomes

Abstract

To verify if data obtained in the prehospital evaluation of patients with severe acute respiratory syndrome (SARS) during the initial response to the COVID-19 pandemic is associated with clinical outcomes: mechanical ventilation, hospital discharge, and death. This is a retrospective analysis involving secondary data from the Emergency Medical Service (EMS) records and the Health Surveillance Information System of patients assisted by the EMS in Manaus, from January to June 2020, the period of the first peak of COVID-19 cases. The combination of the two databases yielded a total of 1.190 patients, who received a first EMS response and were later admitted to hospital with SARS and had data on clinical outcomes of interest available. Patients were predominantly male (754, 63.4%), with a median age of 66 (IQR: 54.0–78.0) years. SARS illness before medical assistance was associated to need for invasive mechanical ventilation (IMV, p < 0.001). Lower pre-hospital SpO2 was associated to death (p = 0.025). Death was more common among patients with respiratory support needs, especially in the invasive ventilation group (262/287; 91.3%) (p < 0.001). In addition, IMV was more common among elderly individuals (p < 0.001). Patients admitted to ICU had a greater chance of dying when compared to non-ICU admitted patients (p < 0.001), and closely related to IMV (p < 0.001). Patients in ICU were also older (p = 0.003) and had longer hospital stay (p < 0.001). Mortality was associated with mechanical ventilation (p < 0.001), ICU admission (p < 0.001), and older age (p < 0.001). Patients who died had a shorter length of both ICU and total hospital stay (p < 0.001). Prehospital EMS may provide feasible and early recognition of critical patients with SARS in strained healthcare systems, such as in low-resource settings and pandemics.