Editing Respiratory failure (section)

===Type 3===
Type 3 respiratory failure is a type of Type 1 respiratory failure, with decreased PaO2 (hypoxemia) and either normal or decreased PaCO2.<ref name=mirabile/> However, because of its prevalence, it has been given its own category. Type 3 respiratory failure is often referred to as peri-operative respiratory failure, because it is distinguished by being a Type 1 respiratory failure that is specifically associated with an operation, procedure, or surgery.<ref>{{Cite web |title=Acute respiratory failure |url=https://www.mcgill.ca/criticalcare/education/teaching/teaching-files/acute-respiratory-failure |access-date=2023-10-28 |website=Department of Critical Care |language=en}}</ref>

The pathophysiology of type 3 respiratory failure often includes lung atelectasis, which is a term used to describe a collapsing of the functional units of the lung that allow for gas exchange. Because atelectasis occurs so commonly in the perioperative period, this form is also called  perioperative respiratory failure.  After [[General anaesthesia|general anesthesia]], decreases in functional residual capacity  leads to  collapse  of  dependent lung units.<ref name=mirabile/>