RESUMO
BACKGROUND: Rib fractures are a common traumatic injury affecting more than 350,000 patients a year. Early stabilization has shown to be effective in reducing pulmonary complications. Platelet-rich plasma (PRP) is a growth factor-rich blood product known to improve soft tissue and bone healing. We hypothesized that the addition of PRP to a rib fracture site would accelerate callus formation and improve callus strength. METHODS: Platelet-rich plasma was isolated from pooled Lewis rat blood and quantified. Thirty-two Lewis rats underwent fracture of the sixth rib and were treated with 100 µL PRP (1 × 106 platelets/µL) or saline. At 2 weeks, ribs were harvested and underwent a 3-point bend, x-ray, and microcomputed tomography, and callus sections were stained with 4',6-diamidino-2-phenylindole and Alcian blue and picrosirius red. At 6 weeks, ribs were harvested and underwent a 3-point bend test, x-ray, microcomputed tomography, and Alcian blue and picrosirius red staining. RESULTS: At 2 weeks, PRP increased callus diameter (9.3 mm vs. 4.3 mm, p = 0.0002), callus index (4.5 vs. 2.1, p = 0.0002), bone volume/total volume (0.0551 vs. 0.0361, p = 0.0024), cellularization (2,364 vs. 1,196, p < 0.0001), and cartilage (12.12% vs. 3.11%, p = 0.0001) and collagen (6.64% vs. 4.85%, p = 0.0087) content compared with controls. At 6 weeks, PRP increased fracture callus diameter (5.0 mm vs. 4.0 mm, 0.0466), callus index (2.5 vs. 2.0, p = 0.0466), BV/TV (0.0415 vs. 0.0308, p = 0.0358), and higher cartilage (8.21% vs. 3.26%, p < 0.0001) and collagen (37.61% vs. 28.00%, p = 0.0022) content compared with controls. At 6 weeks, PRP samples trended toward improved mechanical characteristics; however, these results did not reach significance (p > 0.05). CONCLUSION: Rib fractures are a common injury, and accelerated stabilization could improve clinical outcomes. Platelet-rich plasma significantly increased callus size, calcium deposition, and cartilage and collagen content at 2 and 6 weeks and trended toward improved strength and toughness on mechanical analysis at 6 weeks compared with controls, although this did not reach significance. These findings suggest that PRP may be a useful adjunct to accelerate and improve fracture healing in high-risk patients.
RESUMO
Long-term continuous-flow left ventricular assist device (CFLVAD) therapy is limited by complications. Compared with stroke and renal dysfunction, post-CFLVAD bowel ischemia is poorly characterized. Adult patients who underwent first-time durable CFLVAD implantation at our institution between 2008 and 2018 were identified and screened for bowel ischemia using Current Procedural Terminology codes for abdominal surgical exploration and International Classification of Disease codes for intestinal vascular insufficiency. Patients who developed biopsy-proven bowel ischemia (cases) were matched to controls (1:1, nearest neighbor, caliper = 0.29) based on preoperative characteristics. Incidences of postoperative right heart failure and renal replacement therapy were compared using McNemar's test. One year survival was estimated using the Kaplan-Meier method. Overall, 711 patients underwent CFLVAD implantation. Nineteen (2.7%) developed bowel ischemia (cases) median 17 days postimplantation (IQR 8-71). The majority of cases were male (78.9%), Black (63.2%), received HeartMate II (57.9%), treated as destination therapy (78.9%), and had a history of hypertension (89.5%), chronic kidney disease (84.2%), hyperlipidemia (84.2%), smoking (78.9%), and atrial fibrillation (57.9%). Post-LVAD, case patients were more likely to develop moderate-severe right heart failure (89.5% vs. 68.4%, p = 0.005), require renal replacement therapy (21.1% vs. 0%, p < 0.001), and less likely to survive to discharge (52.6% vs. 89.5%, p = 0.02) compared with controls. Case subjects demonstrated worse 1 year survival. While less common than stroke and renal dysfunction, post-CFLVAD bowel ischemia is associated with high 1 year mortality. Multi-institutional registries should consider reporting abdominal complications such as bowel ischemia as an adverse event to further investigate these trends and identify predictors of this complication to reduce patient mortality.