Cascade iatrogenesis: a case-control study to detect postoperative respiratory failure in hospitalized older adults.

During hospitalization, older adults are at high risk for cascade iatrogenesis, the serial development of complications. In this retrospective, descriptive, case-control pilot study, 28 patients (cases) who developed respiratory failure after an elective surgical procedure were compared to 28 matched controls who did not develop postoperative respiratory failure. The type, frequency, and timing of events that preceded the development of postoperative respiratory failure in hospitalized older adults (age 65 and older) and the presence and timing of similar events for matched controls during a postoperative period of the same length were recorded. Cases experienced certain trigger events, including atelectasis and fluid overload, at significantly higher rates than controls. Cases and controls experienced similar rates of oversedation and delirium, yet controls were less likely to aspirate following these episodes. Patients who developed postoperative respiratory failure were less likely to ambulate early and experienced more calls to rapid response or code teams, more transfers to higher levels of care, longer lengths of stay, and more deaths than matched controls.