Outcomes of the resuscitative and emergency thoracotomy at a Dutch level-one trauma center: are there predictive factors for survival?

PURPOSE: To investigate the 30-day survival rate of resuscitative and emergency thoracotomies in trauma patients. Moreover, factors that positively influence 30-day survival rates were investigated. METHODS: A retrospective study of patients (> 16 years), between 2008 and 2020, who underwent a resuscitative or emergency thoracotomy at a level-one trauma center in the Netherlands was conducted. RESULTS: Fifty-six patients underwent a resuscitative (n = 45, 80%) or emergency (n = 11, 20%) thoracotomy. The overall 30-day survival rate was 32% (n = 18), which was 23% after blunt trauma and 72% after penetrating trauma, and which was 18% for the resuscitative thoracotomy and 91% for the emergency thoracotomy. The patients who survived had full neurologic recovery. Factors associated with survival were penetrating trauma (p < 0.001), (any) sign of life (SOL) upon presentation to the hospital (p = 0.005), Glasgow Coma Scale (GCS) of 15 (p < 0.001) and a thoracotomy in the operating room (OR) (p = 0.018). Every resuscitative thoracotomy after blunt trauma and pulseless electrical activity (PEA) or asystole in the pre-hospital phase was futile (0 survivors out of 11 patients), of those patients seven (64%) had concomitant severe neuro-trauma. CONCLUSION: This study found a 30-day survival rate of 32% for resuscitative and emergency thoracotomies, all with good neurological recovery. Factors associated with survival were related to the trauma mechanism, the thoracotomy indication and response to resuscitation prior to thoracotomy (for instance, if resuscitation enables enough time for safe transport to the operating room, survival chances increase). Resuscitative thoracotomies after blunt trauma in combination with loss of SOL before arrival at the emergency room were in all cases futile, interestingly in nearly all cases due to concomitant neuro-trauma.

The use of a cartilage decellularized matrix scaffold for the repair of osteochondral defects: the importance of long-term studies in a large animal model.

OBJECTIVE: To investigate the effect of decellularized cartilage-derived matrix (CDM) scaffolds, by itself and as a composite scaffold with a calcium phosphate (CaP) base, for the repair of osteochondral defects. It was hypothesized that the chondral defects would heal with fibrocartilaginous tissue and that the composite scaffold would result in better bone formation. METHODS: After an 8-week pilot experiment in a single horse, scaffolds were implanted in eight healthy horses in osteochondral defects on the medial trochlear ridge of the femur. In one joint a composite CDM-CaP scaffold was implanted (+P), in the contralateral joint a CDM only (-P) scaffold. After euthanasia at 6 months, tissues were analysed by histology, immunohistochemistry, micro-CT, biochemistry and biomechanical evaluation. RESULTS: The 8-week pilot showed encouraging formation of bone and cartilage, but incomplete defect filling. At 6 months, micro-CT and histology showed much more limited filling of the defect, but the CaP component of the +P scaffolds was well integrated with the surrounding bone. The repair tissue was fibrotic with high collagen type I and low type II content and with no differences between the groups. There were also no biochemical differences between the groups and repair tissue was much less stiff than normal tissue (P < 0.0001). CONCLUSIONS: The implants failed to produce reasonable repair tissue in this osteochondral defect model, although the CaP base in the -P group integrated well with the recipient bone. The study stresses the importance of long-term in vivo studies to assess the efficacy of cartilage repair techniques.

Multipotent Stromal Cells Outperform Chondrocytes on Cartilage-Derived Matrix Scaffolds.

OBJECTIVE: Although extracellular matrix (ECM)-derived scaffolds have been extensively studied and applied in a number of clinical applications, the use of ECM as a biomaterial for (osteo)chondral regeneration is less extensively explored. This study aimed at evaluating the chondrogenic potential of cells seeded on cartilage-derived matrix (CDM) scaffolds in vitro. DESIGN: Scaffolds were generated from decellularized equine articular cartilage and seeded with either chondrocytes or multipotent stromal cells (MSCs). After 2, 4, and 6 weeks of in vitro culture, CDM constructs were analyzed both histologically (hematoxylin and eosin, Safranin-O, collagen types I and II) and biochemically (glycosaminoglycan [GAG] and DNA content). RESULTS: After 4 weeks, both cell types demonstrated chondrogenic differentiation; however, the MSCs significantly outperformed chondrocytes in producing new GAG-containing cartilaginous matrix. CONCLUSION: These promising in vitro results underscore the potency of CDM scaffolds in (osteo)chondral defect repair.

Comparative study of depth-dependent characteristics of equine and human osteochondral tissue from the medial and lateral femoral condyles.

Articular cartilage defects are common after joint injuries. When left untreated, the biomechanical protective function of cartilage is gradually lost, making the joint more susceptible to further damage, causing progressive loss of joint function and eventually osteoarthritis (OA). In the process of translating promising tissue-engineering cartilage repair approaches from bench to bedside, pre-clinical animal models including mice, rabbits, goats, and horses, are widely used. The equine species is becoming an increasingly popular model for the in vivo evaluation of regenerative orthopaedic approaches. As there is also an increasing body of evidence suggesting that successful lasting tissue reconstruction requires an implant that mimics natural tissue organization, it is imperative that depth-dependent characteristics of equine osteochondral tissue are known, to assess to what extent they resemble those in humans. Therefore, osteochondral cores (4-8 mm) were obtained from the medial and lateral femoral condyles of equine and human donors. Cores were processed for histology and for biochemical quantification of DNA, glycosaminoglycan (GAG) and collagen content. Equine and human osteochondral tissues possess similar geometrical (thickness) and organizational (GAG, collagen and DNA distribution with depth) features. These comparable trends further underscore the validity of the equine model for the evaluation of regenerative approaches for articular cartilage.

Formalin fixation affects equilibrium partitioning of an ionic contrast agent-microcomputed tomography (EPIC-µCT) imaging of osteochondral samples.

OBJECTIVE: Equilibrium Partitioning of an Ionic Contrast agent with microcomputed tomography (EPIC-µCT) is a non-invasive technique to quantify and visualize the three-dimensional distribution of glycosaminoglycans (GAGs) in fresh cartilage tissue. However, it is unclear whether this technique is applicable to already fixed tissues. Therefore, this study aimed at investigating whether formalin fixation of bovine cartilage affects X-ray attenuation, and thus the interpretation of EPIC-µCT data. DESIGN: Osteochondral samples (n=24) were incubated with ioxaglate, an ionic contrast agent, for 22h prior to µCT scanning. The samples were scanned in both formalin-fixed and fresh conditions. GAG content was measured using a biochemical assay and normalized to wet weight, dry weight, and water content to determine potential reasons for differences in X-ray attenuation. RESULTS: The expected zonal distribution of contrast agent/GAGs was observed for both fixed and fresh cartilage specimens. However, despite no significant differences in GAG concentrations or physical properties between fixed and fresh samples, the average attenuation levels of formalin-fixed cartilage were 14.3% lower than in fresh samples. CONCLUSIONS: EPIC-µCT is useful for three-dimensional visualization of GAGs in formalin-fixed cartilage. However, a significant reduction in X-ray attenuation for fixed (compared to fresh) cartilage must be taken into account and adjusted for accordingly when quantifying GAG concentrations using EPIC-µCT.