Ventilator-Associated Pneumonia after Rib Fixation: A National Trauma Data Bank Analysis

Author(s):
Solomon Feuerwerker; Stas Amato; Gary An

Background:

Rib fractures are common in trauma and are associated with substantial morbidity. Operative rib fixation (ORF) has been shown to reduce morbidity (i.e., lower subjective pain scores and duration of mechanical ventilation) and mortality of this injury. It has also been proposed that ORF is associated with decreased risk of pneumonia. We aim to investigate outcomes after ORF using a large national database.

Hypothesis:

In patients with multiple rib fractures and exposure to mechanical ventilation (MV), ORF is associated with decreased odds of ventilator-associated pneumonia (VAP).

Methods:

We performed a retrospective cohort study utilizing the National Trauma Data Bank (NTDB) for 2020-2021. Inclusion criteria were age ≥ 18 with multiple rib fractures (+/- flail segments), any period of MV, and survival greater than 24 hours after presentation. Patients with severe head, neck, or abdominal injury (Abbreviated Injury Scale > 3) were excluded. Patients were characterized based on presence of ORF intervention. Univariate statistics and multivariable regression were used to compare differences and outcomes between patient groups. We controlled for demographics, injury severity, trauma mechanism (blunt vs. penetrating), initial respiratory vital signs, days on MV, and comorbidities. Outcomes of interest included VAP and mortality.

Results:

28933 patients were included in the study, 2367 (8.2%) underwent ORF while 26566 (91.8%) did not. Patients who received ORF were older, with mean age of 55.4 compared to 52.1 (p<0.001). The ORF cohort had fewer female patients (22.5 vs 26.0%, p<0.001) and less African-American patients (10.4 vs 15%, p<0.001). Patients with private/commercial insurance had more ORF (44.5 vs 39.4%, p<0.001). Median injury severity score was higher in the ORF group (22 vs 20, p<0.001). A diagnosis of flail chest was significantly more common in the ORF group (46.4 vs 8.3%, p<0.001). On regression analysis, ORF was not found to be associated with lower odds of VAP (aOR 1.62, 95% CI 0.71-3.71), but was associated with decreased mortality (aOR 0.22, 95% CI 0.06-0.73).

Conclusions:

In this national sample analysis, we investigated the effects of operative rib fixation on VAP and mortality in adults with multiple rib fractures and a period of mechanical ventilation. We found that patients who underwent ORF did not have lower odds of VAP when compared to patients who underwent nonoperative management but did have significantly lower odds of mortality. Given the discordance in findings between our study and previous literature with respect to VAP risk, further prospective studies are warranted.