Rationing Scarce Healthcare Capacity: A Study Of The Ventilator Allocation Guidelines During The COVID-19 Pandemic In The United States

Abstract

In the United States, even though national guidelines for allocating scarce healthcare resources are lacking, 26 states have specific ventilator allocation guidelines to be invoked in case of a shortage. While several states developed their guidelines in response to the recent Covid-19 pandemic, NYS developed these guidelines in 2015 as "pandemic influenza is a foreseeable threat, one that we cannot ignore." The primary objective of this study is to assess the existing procedures and priority rules in place for allocating/rationing scarce ventilator capacity and propose alternative (and improved) priority schemes. We first build machine learning models using inpatient records of COVID-19 patients admitted to New York-Presbyterian/Columbia University Irving Medical Center and an affiliated community health center to predict survival probabilities as well as ventilator length-of-use. Then, we use the resulting point estimators and their uncertainties as inputs for a multi-class priority queueing model with abandonments to assess three priority schemes: (i) SOFA-P, which most closely mimics the existing practice by prioritizing patients with sufficiently low Sequential Organ Failure Assessment (SOFA) scores, (ii) ISP, which assigns priority based on patient-level survival predictions, and (iii) ISP-LU, which takes into account survival predictions and resource use duration. Our findings highlight that our proposed priority scheme, ISP-LU, achieves a demonstrable improvement over the other two alternatives. Specifically, the expected number of survivals increases and death risk while waiting for ventilator use decreases. We also show that ISP-LU is a robust priority scheme whose implementation yields a Pareto-improvement over both ISP and SOFA-P in terms of maximizing saved lives after mechanical ventilation while limiting racial disparity in access to the priority queue.