Background: Early fixation (<24 hour) of femur fractures with an intramedullary nail (IMN) has been associated with a decreased incidence of pulmonary complication (PC) in stable trauma patients. Early fixation is in accordance with the "two-hit" hypothesis, that is, an increase in proinflammatory markers during Days 3 to 5 after injury, increases the risk of developing a PC. We hypothesized that early IMN fixation of femur fractures would be associated with a decreased incidence of PC, hospital stay, and overall charges.
Methods: A retrospective review of all trauma patients with diaphyseal femur fractures was performed from January 2000 through December 2010 at an academic Level 1 trauma center. The cohort was divided into those who underwent early fixation (<24 hours) and delayed fixation (≥24 hours). Multivariable logistic regression modeling was used to adjust for the anatomic (Injury Severity Score [ISS]) and physiologic (Revised Trauma Score [RTS]) severity of injury. The primary outcome of interest was PC, defined as the presence of pneumonia (PNA), pulmonary embolism, or adult respiratory distress syndrome. Continuous variables are expressed as mean (SD). The analysis was repeated for patients with an ISS of greater than 15 and an ISS of greater than 25.
Results: During the study period, 1,755 patients were admitted with a diaphyseal femur fracture, of whom 1,376 patients underwent primary IMN. A total of 1,032 (75%) underwent early fixation (median, 7.4 hours; interquartile range [IQR], 3.7-12.9 hours), and 344 (25%) underwent delayed fixation (median, 40.9 hours; IQR, 31.0-64.9 hours). The early fixation group had lower ISS (median [IQR], 10 [10-19] vs. 17.5 [10-27]; p < 0.001) and a higher RTS (median [IQR], 7.84 [7.84-7.84] vs. 7.84 [7.84-7.84]; p < 0.001). PC were reduced in the early fixation group, (3.9% vs. 13.4%, p < 0.001). Specifically, there was a decreased incidence of PNA (2% vs. 11%, p < 0.001), pulmonary embolism (2% vs. 4%, p < 0.21), and adult respiratory distress syndrome (0.002% vs. 0.02%, p < 0.001). After adjustment for anatomic (ISS) and physiologic (RTS) indices of injury severity, early fixation was independently associated with a reduction in PC (odds ratio, 0.43; 95% confidence interval, 0.25-0.72; p = 0.002). The early fixation group also had a decrease in hospital length of stay (median [IQR], 6 [4-11] vs. 10 [6-17]; p < 0.001), ventilator days (median [IQR], 0 [0-0] vs. 0 [0-4]; p < 0.001), and hospital charges (median [IQR], $59,561 [$38,618-$106,780] vs. $97,018 [48,249-205,570]; p < 0.001). Mortality was low in both groups (0.4% vs. 1.7%, p < 0.01). Similar results were seen in patients with an ISS of greater than 15 and ISS of greater than 25.
Conclusion: Controlling for anatomic and physiologic severity of injury, early femoral IMN was associated with an almost 60% reduction in odds of developing PCs. Early fixation was also associated with a reduction ventilator days, hospital length of stay, and overall hospital charges. As the list of "never events" continues to expand and improving quality of care while reducing costs is emphasized, early (<24 hours) definitive operative intervention seems to decrease complications, achieve early hospital discharge, and reduce hospital charges.
Level of evidence: Therapeutic study, level IV.