Vital capacity helps predict pulmonary complications after rib fractures

Traumatic rib fractures are associated with significant morbidity. Vital capacity (VC) assesses pulmonary function; however, limited data link VC to patient outcomes. Our objective was to determine if VC predicted complications and disposition in patients with rib fractures.

This is a retrospective chart review of all patients with fractured ribs admitted to a Level 1 trauma center during a 4-year period. Patients were excluded if no VC was performed within 48 hours of admission. Data collected included demographics, hospital/intensive care unit length of stay, epidural, discharge to home versus extended care facility, mortality, chest Abbreviated Injury Scale (AIS) score, Injury Severity Score (ISS), number of rib fractures, hemothorax/pneumothorax, presence of pulmonary contusion, presence of chest tube, chronic obstructive pulmonary disease, and average daily VC (percentage of predicted). Pulmonary complication was defined as pneumonia, need for intubation, new home O2 requirement, readmission for pulmonary issue, or intensive care unit transfer. Statistical analysis was performed using χ and multivariate logistic regression.

Of 801 patients with rib fractures, 683 had VC performed within 48 hours. Average age was 53 years, median ISS was 13 (interquartile range, 9-18), and median length of stay was 5 days. Most (72%) were discharged home, and 26% went to extended care facility. Ten percent developed a pulmonary complication, and there were nine deaths. Every 10% increase in VC was associated with 36% decrease in likelihood of pulmonary complication. Patients with a VC greater than 50% had a significantly lower association of pulmonary complication (p = 0.017), and a VC of less than 30% was independently associated with pulmonary complication (odds ratio, 2.36).

Patients with fractured ribs and VC of less than 30% have significant association for pulmonary complication. Higher VC is associated with lower likelihood of pulmonary complication. VC may help identify those at risk for complications after rib fractures, but a prospective study is necessary to confirm these findings.

Prognostic/epidemiologic study, level IV.