Background: Older adults with isolated rib fractures are often admitted to an intensive care unit (ICU) because of presumedly increased morbidity and mortality. However, evidencebased guidelines are limited. We sought to identify characteristics of these patients that predict the need for ICU care. Materials and methods: We analyzed patients !50 y old at our center during 2013-2017 whose only indication for ICU admission, if any, was isolated rib fractures. The primary outcome was any critical care intervention (e.g., intubation) or adverse event (e.g., hypoxemia) (CCIE) based on accepted critical care guidelines. We used stepwise logistic regression to identify characteristics that predict CCIEs. Results: Among 401 patients, 251 (63%) were admitted to an ICU. Eighty-three patients (33%) admitted to an ICU and 7 (5%) admitted to the ward experienced a CCIE. The most common CCIEs were hypotension (10%), frequent respiratory therapy (9%), and oxygen desaturation (8%). Predictors of CCIEs included incentive spirometry <1 L (OR 4.72, 95% CI 2.14-10.45); use of a walker (OR 2.86, 95% CI 1.29-6.34); increased chest Abbreviated Injury Scale score (AIS 3