Briefly occlusive coronary anastomosis with tissue adhesive

Comparison of polyurethane with cyanoacrylate in hemostasis of vascular injury in guinea pigs

OBJECTIVE

To evaluate the behavior of castor oil-derived polyurethane as a hemostatic agent and tissue response after abdominal aortic injury and to compare it with 2-octyl-cyanoacrylate.

METHODS

Twenty-four Guinea Pigs were randomly divided into three groups of eight animals (I, II, and III). The infrarenal abdominal aorta was dissected, clamped proximally and distally to the vascular puncture site. In group I (control), hemostasis was achieved with digital pressure; in group II (polyurethane) castor oil-derived polyurethane was applied, and in group III (cyanoacrylate), 2-octyl-cyanoacrylate was used. Group II was subdivided into IIA and IIB according to the time of preparation of the hemostatic agent.

RESULTS

Mean blood loss in groups IIA, IIB and III was 0.002 grams (g), 0.008 g, and 0.170 g, with standard deviation of 0.005 g, 0.005 g, and 0.424 g, respectively (P=0.069). The drying time for cyanoacrylate averaged 81.5 seconds (s) (standard deviation: 51.5 seconds) and 126.1 s (standard deviation: 23.0 s) for polyurethane B (P=0.046). However, there was a trend (P=0.069) for cyanoacrylate to dry more slowly than polyurethane A (mean: 40.5 s; SD: 8.6 s). Furthermore, polyurethane A had a shorter drying time than polyurethane B (P=0.003), mean IIA of 40.5 s (standard deviation: 8.6 s). In group III, 100% of the animals had mild/severe fibrosis, while in group II only 12.5% showed this degree of fibrosis (P=0.001).

CONCLUSION

Polyurethane derived from castor oil showed similar hemostatic behavior to octyl-2-cyanoacrylate. There was less perivascular tissue response with polyurethane when compared with cyanoacrylate.

Non-suture technique for rabbit oviduct anastomosis with 2-octyl cyanoacrylate: a histopathologic and biomechanical analysis

AIM

The aim of this study was to investigate histological and biomechanical properties of oviduct anastomosis with 2-octyl cyanoacrylate (OCA) in the rabbit.

MATERIAL AND METHODS

Sixty female rabbits were randomly divided equally into three groups: A (control), B (traditional catgut suture), and C (non-suture technique using OCA). After suture or OCA anastomosis, gross examination (adhesion formation) and histopathology (hematoxylin-eosin), ultrastructure (transmission electron microscopy), and biomechanics (bursting pressure) on para-anastomotic site were investigated on oviduct taken at 1 (A1, B1, C1) and 4 (A2, B2, C2) weeks, respectively.

RESULTS

Adhesion score in group B was more severe than that in groups A and C at 1 and 4 weeks. Histopathology showed that acute endosalpingitis in group B was the most intense at 1 week, followed by significantly more tissue stimulation induced by catgut and foreign-body giant cells in group B than in group C at 4 weeks. Ultrastructural damage of ciliated cells was reversed partly (B2) and completely (C2) at 4 weeks. Bursting pressure in C1 was weaker than that in B1, followed by no significant difference at 4 weeks.

CONCLUSION

Non-suture using OCA for oviduct anastomosis can be accepted as a new-perspective technique.

Isocyanate-functional adhesives for biomedical applications. Biocompatibility and feasibility study for vascular closure applications

Biodegradable isocyanate-functional adhesives based on poly(ethylene glycol)-adipic acid esters were synthesized, characterized, and evaluated in vitro and in vivo. Two types of formulations, P2TT and P2MT, were developed by functionalization with 2,4-tolylene diisocyanate (TDI) or 4,4'-methylene-bis(phenyl isocyanate) (MDI), respectively, and branching with 1,1,1-trimethylolpropane (TMP). The biocompatibility of the synthesized adhesive formulations was evaluated as per ISO 10993. Cytotoxicity, systemic toxicity, pyrogenicity, genotoxicity (reverse mutation of Salmonella typhimurium and Escherichia coli), hemolysis, intracutaneous reactivity, and delayed-type hypersensitivity were evaluated. All formulations met the requirements of the conducted standard tests. The biological behavior and ability of the adhesive formulations to close an arteriotomy and withstand arterial pressure following partial approximation with a single suture were evaluated in a rat abdominal aorta model. Animals were evaluated at 1, 2, 3, and 4 weeks after surgery. Macroscopic and histopathologic evaluation of explanted arteries suggested that the P2TT formulation had better in vivo performance than the P2MT formulation. Additionally, the P2TT formulation resulted in less tissue reaction than P2MT formulation. To our knowledge, this is the first study demonstrating the potential of this new class of isocyanate-functional degradable adhesives for vascular applications.

Early clinical results with a magnetic connector for distal coronary artery anastomoses

PURPOSE

The main goals in the development of an anastomotic device are to reduce the invasiveness of the procedure and to improve graft patency. We analyze our preliminary clinical experience with the Ventrica magnetic vascular positioner (MVP) series 6000 system.

DESCRIPTION

Eighteen distal anastomoses were performed in 11 patients using the MVP.

EVALUATION

The target artery for MVP was left anterior descending in 9 patients, a marginal branch in 4, the first diagonal branch in 3, and the right coronary artery in 2. Graft material was the left internal thoracic artery in 9 patients, saphenous vein in 6, the right internal thoracic artery in 2, and the radial artery in 1 case. Fifteen anastomoses were performed in an end-to-side and 3 in a side-to-side fashion. Predischarge angiography was performed in 10 of 11 patients. There was a patent MVP anastomosis in all patients.

CONCLUSIONS

Distal anastomoses using the MVP were performed successfully in all patients. The procedure is simple. Short-term patency is excellent. Further randomized trials are necessary to determine long-term safety and patency.

Estudo da cicatrização nas lesões traumáticas esplênicas utilizando octil-2-cianoacrilato e fio de poliglecaprone 25

OBJETIVO: Estudar comparativamente a cicatrização e a formação de aderências em baço de ratos submetidos à trauma operatório e corrigidos utilizando octil-2-cianoacrilato (DE) e fio de poliglecaprone 25 (CA). MÉTODO: 30 ratos machos Wistar foram separados em três grupos de 10 animais, anestesiados de acordo com as normas do COBEA, submetidos à laparotomia xifopúbica e com uma tesoura Metzenbaum, foi realizada uma lesão esplênica com 4mm de profundidade, na borda anti-hilar do pólo inferior do baço. No Grupo CA, suturou-se a lesão com pontos contínuos de poliglecaprone 25; no Grupo DE, com octil-2-cianoacrilato e no Grupo CO, não houve sutura. Após 14 dias, os ratos foram submetidos à eutanásia e as aderências anotadas em protocolo próprio. O estudo anatomopatológico foi realizado nas colorações hematoxilina-eosina e Picro-Sirius, sendo do tipo fechado, duplo-cego. RESULTADOS: O Grupo DE apresentou menos aderências e menor reação de cicatrização tipo corpo estranho que o CA. Ambos mostram quantidade semelhante de colágeno jovem e maduro. CONCLUSÕES: O octil-2-cianoacrilato provocou menos aderências macroscópicas que o fio de poliglecaprone corado e não induziu cicatrização com reação de corpo estranho, mostrando-se efetivo no reparo das lesões traumáticas esplênicas, em ratos.

Using Dermabond for Wound Closure in Lumbar and Cervical Neurosurgical Procedures

OBJECTIVE:

2-Octylcyanoacrylate (Dermabond; Ethicon, Inc., Somerville, NJ) is a liquid adhesive being used with increasing frequency for the closure of lacerations and surgical incisions. Dermabond provides excellent cosmetic closure, and recent studies have demonstrated very low infection risks when it is properly applied. There are no published studies using Dermabond on lumbar or cervical procedures. This study was undertaken to determine whether Dermabond is safe and efficacious to use in these common neurosurgical procedures.

METHODS:

Records of 200 consecutive patients with Dermabond closure after anterior cervical discectomy, microlumbar discectomy, or lumbar laminectomy by the senior author (JEB) with a mean follow-up time of 5.42 months were retrospectively reviewed. Suspected infections with or without confirmatory cultures, erythema, and incisional drainage were documented.

RESULTS:

Of 200 patients, 85 underwent microlumbar discectomy, 22 lumbar laminectomy, and 93 anterior cervical discectomy. There was only 1 definitive infection, which was a culture-proven discitis in a microlumbar discectomy patient. Of the remaining 85 microlumbar discectomies, there was 1 transient incisional erythema. Of the 22 lumbar laminectomies, there was 1 patient with clinical superficial wound infection with negative cultures and 4 patients with transient incisional drainage without infection. Of the 93 anterior cervical discectomies, 2 had transient incisional drainage without infection.

CONCLUSION:

This study demonstrates that Dermabond is safe to use in neurosurgery patients undergoing lumbar or cervical procedures, with only 1 patient of 200 having a proven infection. Patients are able to shower and do not have sutures or staples to remove. Patient responses are overwhelmingly positive.