Emergency triage of Covid-19 patients using chest X-rays

In emergency rooms across the world, doctors facing hospital bed shortages must make a difficult judgment call: is a patient with respiratory infection safe to go home? Or is close monitoring in the hospital, or even the ICU, needed? Getting this right is critical not just to save lives, but also to optimize scarce hospital resources. Reports from the front lines of the Covid-19 pandemic indicate that the current state of medical knowledge is failing here. Empirically, many patients are admitted to the hospital, but ultimately do not require advanced care—a waste of beds. Other patients look well enough to be sent home, only to deteriorate rapidly, returning to the ER in profound respiratory distress—or not returning at all. The key to solving this problem could lie in the chest x-ray, a rapid, cheap diagnostic that nearly all patients with respiratory complaints get in the ER. It's clear to front-line doctors that there is a signal in the x-ray image for predicting impending pulmonary collapse. But this signal can be devilishly hard to find. Indeed, some health systems explicitly require senior physicians to personally review x-rays before a patient is sent home from the ER, in the hope that expending their scarcest resource—doctors' time—can help catch high-risk patients in time.