care for all patients. Triage In the event of a future pandemic, the number of patients that require additional respiratory support will outnumber the number of available ventilators. Although a hypothetical example, similar natural disasters have occurred in the past. Historically, the influenza pandemic of 1918-19 and the more recent SARS epidemic in 2003 led to resource scarcity and necessitated triage. One paper estimated that in the United States, the need for ventilators would be double the number available in the setting of an influenza pandemic similar to the scale of 1918. In other countries with fewer resources, shortages are postulated to be even more severe. How, then, is a clinician to decide whom to offer this treatment? Examples of common approaches that guide triage include "saving the most lives", calling for care to be provided to "the sickest first" or alternatively a "first come, first served" approach may attempt to sidestep the difficult decision of triage. Emergency services often use their own triaging systems to be able to work through some of these challenging situations; however, these guidelines often assume no resource scarcity, and therefore, different triaging systems must be developed for resource-limited, disaster response settings. Useful ethical approaches to guide the development of such triaging protocols are often based on the principles of the theories of utilitarianism, egalitarianism and proceduralism. Utilitarian Approach The Utilitarian theory works on the premise that the responder shall 'maximise collective welfare'; or in other words, 'do the greatest good for the greatest numbers of people'. The utilitarian will necessarily need a measure by which to assess the outcome of the intervention. This could be thought of through various ways, for instance: the number of lives saved, or the number of years of life saved through the intervention. Thus, the utilitarian would prioritize saving the youngest of the patients over the elderly or those who are more likely to die despite an intervention, in order to 'maximise the collective years of life saved'. Commonly used metrics to quantify utility of health interventions include DALYs (Disability Adjusted Life Years) and QALYs (Quality Adjusted Life Years) which take into account the potential number of years of life lost due to disability and the quality of the life that has been saved, respectively, in order to quantify the utility of the intervention. Egalitarian Approach Principles of egalitarianism suggest the distribution of scarce resources amongst all those in