Vascular graft selection

Comparison of Contralateral vs Ipsilateral Vein Graft for Traumatic Vascular Injury Repair: A Cohort From PROOVIT

Traumatic injury leading to arterial damage has traditionally been repaired using autologous vein graft from the contralateral limb. This often requires a secondary surgical site and the potential of prolonged operative time for patients. We sought to assess the use of ipsilateral vs contralateral vein grafts in patients who experienced traumatic extremity vascular injury. A multicenter database was queried to identify arterial injuries requiring operative intervention with vein grafting. The primary outcome of interest was need for operative reintervention. Secondary outcomes included risk of thrombosis, infection, and intensive care unit length of stay. 358 patients (320 contralateral and 38 ipsilateral) were included in the analysis. The ipsilateral vein cohort did not display a statistically significant decrease in need for reoperation when compared to the contralateral group (11% vs 23%; OR 0.41, 95% CI -0.07-1.3; P = .14). Contralateral repair was associated with longer median intensive care unit (ICU) LOS (4.3 vs 3.1 days; P < .01).

Use of Mesothelial Cells and Biological Matrices for Tissue Engineering of Simple Epithelium Surrogates

Tissue-engineering technologies have progressed rapidly through last decades resulting in the manufacture of quite complex bioartificial tissues with potential use for human organ and tissue regeneration. The manufacture of avascular monolayered tissues such as simple squamous epithelia was initiated a few decades ago and is attracting increasing interest. Their relative morphostructural simplicity makes of their biomimetization a goal, which is currently accessible. The mesothelium is a simple squamous epithelium in nature and is the monolayered tissue lining the walls of large celomic cavities (peritoneal, pericardial, and pleural) and internal organs housed inside. Interestingly, mesothelial cells can be harvested in clinically relevant numbers from several anatomical sources and not less important, they also display high transdifferentiation capacities and are low immunogenic characteristics, which endow these cells with therapeutic interest. Their combination with a suitable scaffold (biocompatible, degradable, and non-immunogenic) may allow the manufacture of tailored serosal membranes biomimetics with potential spanning a wide range of therapeutic applications, principally for the regeneration of simple squamous-like epithelia such as the visceral and parietal mesothelium vascular endothelium and corneal endothelium among others. Herein, we review recent research progresses in mesothelial cells biology and their clinical sources. We make a particular emphasis on reviewing the different types of biological scaffolds suitable for the manufacture of serosal mesothelial membranes biomimetics. Finally, we also review progresses made in mesothelial cells-based therapeutic applications and propose some possible future directions.

Common femoral vein reconstruction using internal jugular vein after blast injury

Common femoral vein traumatic injuries are rare. Surgical management is controversial and by nature case specific. In this report, we present an unusual case of an isolated common femoral vein injury from a gunshot blast repaired with an interposition internal jugular vein bypass. To our knowledge, this is the first reported case of an isolated common femoral vein reconstructed in this manner.

Use of autologous renal capsule grafts for venous repair

OBJECTIVE

To evaluate the efficacy of the renal capsule for reconstruction of the inferior vena cava in a canine model.

MATERIALS AND METHODS

The present study was conducted on 10 dogs; an oval window (2-8 cm long, mean 6.5 cm) was made in the inferior vena cava and then repaired using the autologous renal capsule patch. The patency and functionality of the graft were assessed macroscopically and microscopically 3 months postoperatively.

RESULTS

All the dogs were killed at 3 months, showing excellent patency of the vena cava macroscopically and in the venography. In the microscopic examination, all the patches were completely endothelialized. No evidence of infection or thrombosis was noted.

CONCLUSION

A renal capsule patch can be used for reconstruction of the inferior vena cava. Patency appears to be good, and the risk of infection is low. Moreover, this is an accessible material.

Reconstruction of the Vena Cava with the Peritoneum: The Effect of Temporary Distal Arteriovenous Fistula on Patency (An Experimental Study)

OBJECTIVE

To determine the effect of increasing inferior vena cava blood flow by means of distal arteriovenous fistula on the patency of a peritoneal tube graft.

MATERIALS AND METHODS

In 16 mongrel dogs, a 3-4 cm long circular defect was created at the infrarenal inferior vena cava. The defect was interposed with peritoneal tube graft. A temporary distal femoro-femoral arteriovenous fistula was also constructed in 8 dogs just after the caval interposition. Graft patency was evaluated by Doppler ultrasonography and angiography. Histological evaluation was also performed.

RESULTS

Seven dogs in each group survived. All control grafts occluded within the first week, compared to no occlusions in fistula group (Fisher's exact test, p<0.005). However one 'fistula' dog with a still patent graft was sacrificed on the 18th day due to ultrasonographically occluded arteriovenous fistula.

CONCLUSION

In dogs, the peritoneum may be used as graft material for reconstruction of the inferior vena cava, provided a distal arteriovenous fistula is constructed.

A novel artificial substrate for cell culture: effects of substrate flexibility/malleability on cell growth and morphology

Gels of glyoxyl agarose (GA) are evaluated as a novel flexible substrate for cell culture with physical properties comparable to extracellular matrix (ECM) gels. We show here that cells adhere well to pure GA gels; in addition, specific interactions involving matrix receptors can be studied when individual matrix molecules are bound to the gel covalently. When cells are grown on such substrates, morphology is comparable to that observed on "natural" matrix gels (reconstituted gels of collagen type I or of Matrigel): rather than being flattened as in monolayer cultures on tissue culture plastic the cells assume a rounded morphology and tend to form tissue-like aggregates. The effects of the artificial matrix gels are discussed in the context of previous publications on cell interactions with the extracellular matrix, suggesting that in addition to specific recognition of matrix molecules the physical properties of ECM by themselves can be decisive for cell differentiation. We conclude that gels of glyoxyl agarose a) provide a useful model to mimic the physical properties of matrix gels without the presence of specific adhesion factors; b) may be useful as a general, non-specific ECM allowing cells to be cultured in vitro under conditions favorable for differentiation; and c) allow to design a variety of "synthetic" ECM models composed of a chemically defined gel matrix, which can be supplemented with covalently bound molecules to be recognized by cell surface receptors.

Penetrating injuries of the subclavian vessels

A study was made of 76 patients with subclavian vessel injury. The mechanism of trauma was stabbing in 40 patients (53 per cent) and gunshot in 36 (47 per cent). There were marked differences between the two groups in clinical presentation, operative management and outcome. The group with gunshot injury was characterized by a more immediate threat to life, and a greater need for a median sternotomy and use of interposition grafts. The mortality rate in patients with gunshot wounds was more than twice that in the group with stab injury.