In general, trauma results in disproportionately severe injuries in elderly patients despite similar mechanisms. A frequent concern, specifically, is the risk of pneumonia or intubation associated with rib fractures – previously demonstrated to increase linear for each fracture in patients aged greater than 65.
However, a dichotomous age cut-off paired with a single variable is an obviously simplistic model. These authors retrospectively reviewed 400 patients aged greater than 55 years of age hospitalized with injuries including rib fractures. A regression model was developed to determine predictors of respiratory failure or pulmonary complications.
Six variables shook out of their analysis as significant predictors of subsequent complications: COPD, low serum albumin, use of an ambulatory assist device, a tube thoracostomy in place, injury severity score, and total number of rib fractures. Transforming these variables into a scoring system resulted in a predictive instrument with and AUC of 0.82 (0.77 – 0.88), with sensitivities and specificities in the 70%s based on their chosen threshold.
While this performance is suboptimal, the model has obvious face validity – the frail, severely injured, with underlying pulmonary disease are the most likely to deteriorate. Their model also requires external validation. However, given that most patients do develop pulmonary complications, such a tool could be reasonably used to reduce the costs and resource utilization associated with prophylactic ICU admissions – as long as you were willing to accept the risk of approximately 1 in 20 patients requiring unexpected escalation in care from the floor.
“A pilot single-institution predictive model to guide rib fracture management in elderly patients”
http://www.ncbi.nlm.nih.gov/pubmed/25909417