This blog post is the second part of a series of 3, on a recent lecture I was asked to give on Critical Care Updates: Resuscitation Sequence Intubation. This talk was mostly derived from a podcast by Scott Weingart (Twitter: @EMCrit) where he talked about the physiologic killers during preintubation and perintubation. In this podcast, Scott mentions the HOp killers: Hypotension, Hypoxemia, and Metabolic Acidosis (pH) as the physiologic causes of pre-intubation/peri-intubation morbidity and mortality. Taking care of these critically ill patients that require intubation can be a high stress situation, with little room for error. In part two of this series we will discuss some useful strategies at the bedside to help us reduce pre-intubation/peri-intubation hypoxemia.