2020 Trauma/Critical Care Presentations

Alexander P Nissen, MD, Annelies T Hickerson, MD, Justin Sleeter, MD, Tina Hall, ACNP, James Aden, PhD, Alexander C Mills, DO, Valerie G Sams, MD; San Antonio Military Medical Center

Objective: Complications after traumatic rib fractures are a common consequence of inadequate ventilation. Predicting appropriate level of care is critical to prevent morbidity and mortality. There is a dearth of literature evaluating the utility of bedside spirometry in this population. We sought to examine the utility of bedside forced vital capacity (FVC) in predicting complications for patients suffering blunt traumatic ribs fractures, hypothesizing that admission FVC >50% predicted would be associated with reduced pulmonary complications.

Methods: We report the interim analysis of 79 consecutive adult patients with >3 rib fractures after blunt trauma, admitted to the hospital non-intubated, without cervical spinal cord injury (SCI), or severe traumatic brain injury (TBI) preventing participation in bedside spirometry. All measurements were taken on Wright Mark 8 spirometers (nSpire Health, Longmont, CO). FVC was recorded, and %predicted values calculated using conventional methods. Pulmonary complications represented a composite endpoint defined as any unplanned intubation, ICU readmission, pneumonia, and/or tracheostomy. Conventional statistics were used for comparisons including Wilcoxon’s test for nonparametric continuous variables and Cochrane Armitage trend test for categorical variables.

Results: 79 consecutive patients were enrolled at the time of interim analysis; 23 with admission FVC of 0-29% predicted (low), 36 with admission FVC 30-49% predicted (moderate), and 20 with admission FVC >50% predicted (high). Groups showed similar baseline characteristics including age, smoking status, injury severity score (ISS) and chest abbreviated injury score (AIS), with the exception of pneumothorax being most frequent in the FVC 0-29% predicted group (47.8% vs. 13.9% and 20.0%, p=0.028). The low admission FVC group similarly required tube thoracostomy most frequently, (39.1% vs. 13.9% and 15.0%, p=0.046). Non-home discharge was more frequent in both the low and moderate FVC groups vs. the high admission FVC group (21.7% and 33.3% vs. 5.6%, p=0.031), but pulmonary complications were infrequent in all groups (8.7% vs. 5.6% vs. 0%, p=0.198), with only one death in the entire cohort due to non-pulmonary causes. There were no occurrences of pneumonia, pulmonary embolism, empyema, or aspiration. 

Conclusions: Patients with >3 rib fractures who are non-intubated on admission, and without cervical SCI, severe TBI, or pneumothorax requiring tube thoracostomy represent an apparently low risk group for subsequent pulmonary complications. Those with admission FVC >50% predicted are also at low risk of non-home discharge. Collectively, these factors may define a low risk rib fracture population amenable to further study to prevent over-triage of blunt trauma patients.