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Carotid endarterectomy with a polyurethane patch versus primary closure: a prospective randomized study.

INTRODUCTION: The use of synthetic patch angioplasty during carotid endarterectomy (CEA) has been advocated to reduce restenosis, stroke, and death, but the type of material used is still being debated. This study compared rate of restenosis, neurologic events, and perioperative death in patients undergoing CEA with primary closure versus polyester urethane patch closure. PATIENTS AND METHODS: In a prospective randomized study, we compared patch angioplasty with polyester urethane (Vascular-patch, B. Braun Medical AG, Tuttlingen, Germany) to primary closure between February 1999 and March 2002 in 404 operations. Early (30-day) stroke and mortality rate, long-term restenosis, and neurologic events were compared in the two groups during 2.5 to 5 years of follow-up (median follow-up, 2 years). RESULTS: Primary closure was used in 216 operations, and patch angioplasty was used in 206. Clamping time was significantly shorter in the primary closure group ( P < .001). Perioperative mortality and neurologic events were similar in both groups (1.9% vs 3.9%, P = .21, odds ratio [OR], 2.1; 95% confidence interval [CI], 0.56 to 9.85). The rate of residual stenosis (> or =50%) at 0 or 3-month follow-up was significantly lower in the patch group (2 operations, 1.1%) compared with the primary closure group (17 operations, 8.9%) ( P = .001, OR, 0.114; 95% CI, 0.026 to 0.5). Multivariable logistic regression showed that only primacy closure was found to influence residual stenosis. Restenosis of 70% was significantly less in the patch angioplasty group (2.2% vs 8.6%) ( P = . 01, hazard ratio, 0.246; 95% CI, 0.08 to 0.75). No correlation was found between restenosis and gender, preoperative symptoms, or risk factors. CONCLUSIONS: Patch angioplasty with polyester urethane significantly reduced the restenosis rate ( P = . 01) compared with primary closure. Even though clamping time was longer, patching was not associated with more perioperative complications.

Aged↗

High-pressure suction drainage via a polyurethane foam in the management of poststernotomy mediastinitis.

BACKGROUND: This study was performed to evaluate the effectiveness of suction drainage in the management of early poststernotomy mediastinitis. METHODS: From September 1998 to August 1999, we encountered nine cases of poststernotomy mediastinitis out of 1,209 adult median sternotomies performed in this time period. All these cases were treated with suction drainage, which was recently introduced to our management protocol. From September 1997 to August 1998, we encountered 11 cases of poststernotomy mediastinitis of 1,343 adult median sternotomies. All these cases were initially treated by closed drainage and irrigation, which was our previous first-line management. We used the latter group as historical controls for the evaluation of suction drainage. Lengths of hospitalization were compared using the Mann-Whitney U test, and success versus failure of the primary treatment was compared using the chi2 test. RESULTS: Treatment with the suction dressing resulted in a decreased length of hospitalization after treatment starts (p = 0.02) and a lower rate of treatment failure (p = 0.03). CONCLUSIONS: The use of high-pressure suction drainage is a valuable adjunct in the early management of poststernotomy mediastinitis.

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Structural integrity of the polyurethane female condom after multiple cycles of disinfection, washing, drying and relubrication.

The female condom provides an important alternative means of protection against HIV and other sexually transmitted infections for women, particularly in situations where partners are reluctant or refuse to use male condoms. The relatively high cost of the device, however, is a barrier to its use in resource-poor environments. This has led to some reuse of the product and two studies have demonstrated that female condoms can withstand a limited level of reuse without an excessive loss of structural integrity when washed with soap and water. A consultation on female condom reuse convened by the World Health Organization and the Joint United Nations Programme on AIDS in June 2000 recommended that all used female condoms should be disinfected immediately after use, before washing. The effect of such treatments on the female condom was not known. This study was undertaken to assess the effect of the disinfection, washing, drying and relubrication on the properties of the condom. Samples from three batches of female condoms were subjected to seven treatment cycles before being tested for structural integrity. In all cases the batches of condoms complied with the manufacturer's release specification for the product after treatment. Some minor changes in properties were seen but these were not considered important. There was evidence of a small increase in the number of condoms with holes following repeated disinfection and washing cycles, suggesting that excessive or rough handling can damage the condom. Condoms should therefore be handled carefully and inspected thoroughly for signs of damage after washing and drying before being stored with the intention of subsequently reusing the device.

Single-Use Internal Condom↗

Surface coating of stearyl poly(ethylene oxide) coupling-polymer on polyurethane guiding catheters with poly(ether urethane) film-building additive for biomedical applications.

Three types of stearyl poly(ethylene oxide) (SPEO) with Mn of 2,300, 6,000 and 12,000 were synthesized; accordingly, three types of amphiphilic coupling-polymer SPEO-MDI-SPEO (MSPEO) were prepared by the reactions with 4,4'-methylene diphenyl diisocyanate (MDI). As the surface-modifying additives (SMA), MSPEOs were coated onto the outer wall of the medical guiding catheters. Due to the lack of stability, when coated, MSPEO blended with the film building agent (FBA), poly(ether urethane) (PEL). The process of coating was performed with a lifter. With invariable speed, the PU guiding catheter was vertically dipped into the coating mixture of SMA-MSPEO and FBA-PEL. The surface analysis was carried out by ATR-FTIR and contact angle measurements. It was proved that the surface enrichment of PEO on water interface was much higher than that on air interface. Three kinds of static clotting time tests, PRT, PT and TT, as well as the static platelet adhesion experiment were performed. The results indicated that the coated surface could resist the blood coagulation effectively. In order to test the blood compatibility of the coated catheters under a shear of blood flow, the dynamic experiment was performed with a closed-loop tubular system under a shear rate of 1,500 s(-1). The blood regular testing was carried out on the samples taken out at six different times (0, 5,10, 20, 30 and 60 min). The results were ideal. Finally, the SMA-MSPEO was proved to be non-acute-toxic by LD50 test.

Blood Coagulation↗

Treatment of skin graft donor sites with a semipermeable polyurethane dressing.

The use of a semipermeable dressing for skin graft donor sites has been described. It permits patients with healing donor sites to ambulate, shower, and wear clothing with no pain during the healing phase. Healing is easily monitored, and signs of infection can be detected early and treated promptly, preventing involvement of the full thickness of the wound. Patients can be discharged from the hospital while the donor site is still healing. The dressing can be removed painlessly at home or in the office. The SPD appears superior to any of the more conventional dressings currently in use for treating skin graft donor sites.

Female↗