Hospital saturation and risk of death without receiving mechanical ventilation in hospitalized COVID-19 patients: a city-wide analysis (preprint)

ABSTRACT

Background Pneumonia is the hallmark of severe COVID-19, with supplemental oxygen requirement being the main indication for hospitalization. Refractory hypoxemia in these patients requires invasive mechanical ventilation (IMV) otherwise, death is imminent. In places with a high disease burden, availability of critical care experts, beds, or resources is challenged and many patients could die without receiving them. Methods We performed a retrospective cohort study using open databases from Mexico City about suspected or confirmed COVID-19 patients, health system saturation, and deaths between May 8 th , 2020, and January 5 th , 2021. After building a directed acyclic graph, we performed a binary logistic regression to identify the association between proposed causal variables and dying without receiving IMV (the outcome). Results We included 33 805 hospitalized patients with suspected or confirmed COVID-19, of which 19 820 (58.6%) did not require IMV and survived, 5416 (16.1%) required and received IMV, and 8569 (25.3%) required IMV but died without receiving it. Saturation of IMV-capable beds did not increase the odds of the outcome (odds ratio 1.07, 95% confidence interval 0.94-1.22 of 90%vs50% occupancy), while general bed saturation (2, 1.86-2.14 of 90%vs50% occupancy) and IMV-capable to general bed ratio (1.64, 1.52-1.77 for a ratio of 2vs0.5) did. Private healthcare decreased the odds of the outcome (0.12, 0.08-0.17) and dyspnea increased them (1.33, 1.19-1.9). Conclusions In Mexico City, increased general hospital bed saturation and IMV-capable to general bed ratio were associated with a higher risk of dying without receiving IMV. Private healthcare was the most protective factor. Key messages Hospital saturation has been a central feature of public health messaging, but it is not known how outcomes relate to hospital saturation or capacity. In Mexico City, 90% of COVID-19 patients requiring mechanical ventilation died but less than half received it. Higher general bed saturation and an increased ratio of IMV-capable beds to general beds increased the probability of dying without being intubated while receiving private healthcare decreased this probability. Having available beds to intubate patients is possible thanks to the conversion of general beds, however, still yields suboptimal critical care.