The document discusses the challenges of rationing ventilators during the Covid-19 pandemic. It notes that hospitals in the US only have enough ventilators for a small fraction of patients who may require them. It recommends establishing triage committees to make difficult decisions about withdrawing ventilators from some patients to save others and to reduce the emotional burden on clinicians. The committees would base decisions on objective criteria about likelihood of survival to maximize the number of lives saved during the crisis.