Outcome After Surgical Stabilization of Rib Fractures Versus Nonoperative Treatment in Patients With Multiple Rib Fractures and Moderate to Severe Traumatic Brain Injury (CWIS-TBI)

BACKGROUND Outcomes after surgical stabilization of rib fractures (SSRF) have not been studied in patients with multiple rib fractures and traumatic brain injury (TBI). We hypothesized that SSRF, as compared with nonoperative management, is associated with favorable outcomes in patients with TBI. METHODS A multicenter, retrospective cohort study was performed in patients with rib fractures and TBI between January 2012 and July 2019. Patients who underwent SSRF were compared to those managed nonoperatively. The primary outcome was mechanical ventilation-free days. Secondary outcomes were intensive care unit length of stay and hospital length of stay, tracheostomy, occurrence of complications, neurologic outcome, and mortality. Patients were further stratified into moderate (GCS score, 9–12) and severe (GCS score, ≤8) TBI. RESULTS The study cohort consisted of 456 patients of which 111 (24.3%) underwent SSRF. The SSRF was performed at a median of 3 days, and SSRF-related complication rate was 3.6%. In multivariable analyses, there was no difference in mechanical ventilation-free days between the SSRF and nonoperative groups. The odds of developing pneumonia (odds ratio [OR], 0.59; 95% confidence interval [95% CI], 0.38–0.98; p = 0.043) and 30-day mortality (OR, 0.32; 95% CI, 0.11–0.91; p = 0.032) were significantly lower in the SSRF group. Patients with moderate TBI had similar outcome in both groups. In patients with severe TBI, the odds of 30-day mortality was significantly lower after SSRF (OR, 0.19; 95% CI, 0.04–0.88; p = 0.034). CONCLUSION In patients with multiple rib fractures and TBI, the mechanical ventilation-free days did not differ between the two treatment groups. In addition, SSRF was associated with a significantly lower risk of pneumonia and 30-day mortality. In patients with moderate TBI, outcome was similar. In patients with severe TBI a lower 30-day mortality was observed. There was a low SSRF-related complication risk. These data suggest a potential role for SSRF in select patients with TBI. LEVEL OF EVIDENCE Therapeutic, level IV

Evolution of Stress-Regulated Gene Expression in Duplicate Genes of Arabidopsis thaliana

Due to the selection pressure imposed by highly variable environmental conditions, stress sensing and regulatory response mechanisms in plants are expected to evolve rapidly. One potential source of innovation in plant stress response mechanisms is gene duplication. In this study, we examined the evolution of stress-regulated gene expression among duplicated genes in the model plant Arabidopsis thaliana. Key to this analysis was reconstructing the putative ancestral stress regulation pattern. By comparing the expression patterns of duplicated genes with the patterns of their ancestors, duplicated genes likely lost and gained stress responses at a rapid rate initially, but the rate is close to zero when the synonymous substitution rate (a proxy for time) is >∼0.8. When considering duplicated gene pairs, we found that partitioning of putative ancestral stress responses occurred more frequently compared to cases of parallel retention and loss. Furthermore, the pattern of stress response partitioning was extremely asymmetric. An analysis of putative cis-acting DNA regulatory elements in the promoters of the duplicated stress-regulated genes indicated that the asymmetric partitioning of ancestral stress responses are likely due, at least in part, to differential loss of DNA regulatory elements; the duplicated genes losing most of their stress responses were those that had lost more of the putative cis-acting elements. Finally, duplicate genes that lost most or all of the ancestral responses are more likely to have gained responses to other stresses. Therefore, the retention of duplicates that inherit few or no functions seems to be coupled to neofunctionalization. Taken together, our findings provide new insight into the patterns of evolutionary changes in gene stress responses after duplication and lay the foundation for testing the adaptive significance of stress regulatory changes under highly variable biotic and abiotic environments

A multicenter, prospective, controlled clinical trial of surgical stabilization of rib fractures in patients with severe, nonflail fracture patterns (Chest Wall Injury Society NONFLAIL).

BACKGROUND: The efficacy of surgical stabilization of rib fracture (SSRF) in patients without flail chest has not been studied specifically. We hypothesized that SSRF improves outcomes among patients with displaced rib fractures in the absence of flail chest. METHODS: Multicenter, prospective, controlled, clinical trial (12 centers) comparing SSRF within 72 hours to medical management. Inclusion criteria were three or more ipsilateral, severely displaced rib fractures without flail chest. The trial involved both randomized and observational arms at patient discretion. The primary outcome was the numeric pain score (NPS) at 2-week follow-up. Narcotic consumption, spirometry, pulmonary function tests, pleural space complications (tube thoracostomy or surgery for retained hemothorax or empyema \u3e24 hours from admission) and both overall and respiratory disability-related quality of life (RD-QoL) were also compared. RESULTS: One hundred ten subjects were enrolled. There were no significant differences between subjects who selected randomization (n = 23) versus observation (n = 87); these groups were combined for all analyses. Of the 110 subjects, 51 (46.4%) underwent SSRF. There were no significant baseline differences between the operative and nonoperative groups. At 2-week follow-up, the NPS was significantly lower in the operative, as compared with the nonoperative group (2.9 vs. 4.5, p \u3c 0.01), and RD-QoL was significantly improved (disability score, 21 vs. 25, p = 0.03). Narcotic consumption also trended toward being lower in the operative, as compared with the nonoperative group (0.5 vs. 1.2 narcotic equivalents, p = 0.05). During the index admission, pleural space complications were significantly lower in the operative, as compared with the nonoperative group (0% vs. 10.2%, p = 0.02). CONCLUSION: In this clinical trial, SSRF performed within 72 hours improved the primary outcome of NPS at 2-week follow-up among patients with three or more displaced fractures in the absence of flail chest. These data support the role of SSRF in patients without flail chest. LEVEL OF EVIDENCE: Therapeutic, level II

A Multicenter, Prospective, Controlled Clinical Trial of Surgical Stabilization of Rib Fractures in Patients with Severe, Non-flail Fracture Patterns.

BACKGROUND: The efficacy of surgical stabilization of rib fracture (SSRF) in patients without flail chest has not been studied specifically. We hypothesized that SSRF improves outcomes among patients with displaced rib fractures in the absence of flail chest. METHODS: Multicenter, prospective, controlled, clinical trial (12 centers) comparing SSRF within 72 hours to medical management. Inclusion criteria were three or more ipsilateral, severely displaced rib fractures without flail chest. The trial involved both randomized and observational arms at patient discretion. The primary outcome was the numeric pain score (NPS) at 2-week follow-up. Narcotic consumption, spirometry, pulmonary function tests, pleural space complications (tube thoracostomy or surgery for retained hemothorax or empyema \u3e24 hours from admission) and both overall and respiratory disability-related quality of life (RD-QoL) were also compared. RESULTS: One hundred ten subjects were enrolled. There were no significant differences between subjects who selected randomization (n = 23) versus observation (n = 87); these groups were combined for all analyses. Of the 110 subjects, 51 (46.4%) underwent SSRF. There were no significant baseline differences between the operative and nonoperative groups. At 2-week follow-up, the NPS was significantly lower in the operative, as compared with the nonoperative group (2.9 vs. 4.5, p \u3c 0.01), and RD-QoL was significantly improved (disability score, 21 vs. 25, p = 0.03). Narcotic consumption also trended toward being lower in the operative, as compared with the nonoperative group (0.5 vs. 1.2 narcotic equivalents, p = 0.05). During the index admission, pleural space complications were significantly lower in the operative, as compared with the nonoperative group (0% vs. 10.2%, p = 0.02). CONCLUSION: In this clinical trial, SSRF performed within 72 hours improved the primary outcome of NPS at 2-week follow-up among patients with three or more displaced fractures in the absence of flail chest. These data support the role of SSRF in patients without flail chest. LEVEL OF EVIDENCE: Therapeutic, level II