Ethical, legal and organizational issues in the ICU: Edited by Jeremy M. KahnICU capacity strain and the quality and allocation of critical careHalpern, Scott D.Author Information Division of Pulmonary, Allergy, and Critical Care Medicine, Center for Clinical Epidemiology and Biostatistics, Leonard Davis Institute of Health Economics and Center for Bioethics, Perelman School of Medicine at the University of Pennsylvania, Pennsylvania, Philadelphia, USA Correspondence to Scott D. Halpern, University of Pennsylvania, 723 Blockley Hall, 423 Guardian Drive, Philadelphia, PA 19104-6021, USATel: +1 215 898 1462; fax: +1 215 573 5325; e-mail: [email protected] Current Opinion in Critical Care: December 2011 - Volume 17 - Issue 6 - p 648-657 doi: 10.1097/MCC.0b013e32834c7a53 Buy Metrics Abstract Purpose of review Increasing demand for critical care, with limited potential for comparable expansion of supply, may strain the abilities of ICUs to provide high-quality care in an equitable fashion. Efforts to counter the untoward consequences for the quality and ethics of critical care delivery are limited by the absence of a specific and validated metric of ICU capacity strain. Recent findings This manuscript presents a conceptual framework for ICU capacity strain, considers what data elements may contribute to it, and suggests methods for determining the optimal metric. Next, it outlines the range of potential consequences of increased capacity strain, in terms of both the quality and ethics of care delivered. Finally, consideration is given to how untoward consequences of ICU capacity strain might be mitigated through better understanding of what makes some ICUs better able than others to withstand temporal fluctuations in the demand for their services. Summary Development of an appropriately accurate and parsimonious measure of ICU capacity strain may augment the precision of future critical care outcomes research by reducing unexplained variance attributable to temporal fluctuations in ICU-level factors; elucidate organizational characteristics that make some ICUs better able to withstand high-capacity strain without substantive degradations in quality; and enhance the transparency of critical care rationing while helping to improve its equity and efficiency, thereby promoting the ethics of this inevitable practice. © 2011 Lippincott Williams & Wilkins, Inc.