Clinical application of a nonpenetrating microvascular stapling device for vascularized free tissue transfer

Comparison of a coupling system and the suture method in end-to-side microvascular anastomosis in head and neck reconstruction

BACKGROUND

Use of coupling devices in microvascular anastomosis continues to increase, but it is not yet actively used in end-to-side (ETS) anastomosis because there is no standard method. Therefore, we propose an easy and time-saving ETS micro-anastomosis method using coupling devices in head and neck reconstruction and compare it with the conventional suture method.

MATERIALS AND METHODS

We retrospectively reviewed 30 consecutive cases (43 anastomoses) of ETS anastomosis in head and neck reconstruction from 2018 to 2022. Patient characteristics, operative details, and anastomosis time were evaluated. When using the coupling device, a cross incision was created in the recipient vessel to form vascular flaps. By pulling the flaps out of the ring, the intact vessel lining was fixed. Other procedures were the same as for a traditional anastomosis.

RESULTS

The mean anastomosis time was 12.81 min (range, 6.7-24.87) for the suture and 4.96 min (range, 2.02-9.4) for the coupling device, a statistically significant difference (p-value <.00005). There was no venous insufficiency or flap failure with either method.

CONCLUSIONS

ETS venous anastomosis using the coupling device is an easy-to-use, safe, and timesaving procedure for head and neck reconstruction.

Comparison of total anastomosis time between four different combinations of suturing and knot tying techniques in microsurgical anastomosis

BACKGROUND

Various techniques have been described for performing microsurgical anastomosis with providing high patency rates. Although the total anastomotic time may not be an issue when dealing with a single set of anastomoses, using a faster technique may save significant amount of time in cases of transferring flaps with shorter critical ischemia time or where multiple anastomoses are required. This study compares the total anastomosis time between four different combinations of commonly used suturing and knot tying techniques.

METHODS

Twenty-four rats were divided into 4 groups. Simple interrupted suture with conventional knot tying technique (SIS-CT) was used in group I, continuous suture technique with conventional knot tying (CST) was used in group II, simple interrupted suture with airborne knot tying technique(SIS-AT) was used in group III, and continuous-interrupted suture with airborne knot tying technique(CIS-AT) was used in group IV for microsurgical anastomosis. Total anastomosis time and patency rates with each technique and samples from anastomotic sites were analyzed.

RESULTS

The mean time required for microvascular anastomosis of the femoral artery was 1075 s in group I, 799 s in group II, 844 s in group III, and 973 s in group IV. The difference between four groups was statistically significant. The anastomoses in group II and group III were completed in the shortest period of time. Intergroup comparison revealed that the difference between group II and group III was not statistically significant, however, total anastomosis time for completion of the anastomosis was significantly longer for group I, followed by group IV. Thrombosis rates and histological analysis revealed no significant differences among four groups.

CONCLUSION

CST and SIS-AT techniques can significantly reduce microsurgical anastomosis time and provide high patency rates. Also, the time needed to complete an anastomosis was significantly shorter for CIS-AT when compared to SIS-CT.

Microvascular anastomotic coupler devices versus hand-sewn technique for arterial anastomosis: a systematic review

The use of microvascular anastomotic coupling devices (MACD) is an established technique for venous anastomosis. However, literature on arterial MACD is conflicting. We report, to our knowledge, the first registered systematic review of its kind to evaluate the safety and efficiency of arterial MACD in free flaps. We performed a PRISMA-guided systematic review (PROSPERO-registered) and identified reports using a search algorithm in MEDLINE/EMBASE. The rate of arterial thrombosis was set as the primary outcome. Secondary outcomes included flap survival, failure rates, and comparison of MACD and the conventional hand-sewn technique. From the 17 studies identified, 2672 free flap reconstructions were performed and 640 arterial anastomoses with MACD attempted (622 completed, 97.2%). The pooled incidence of arterial thrombosis was 2.1% (13/622), and overall flap failure rate 4.34% (116/2672). The total number of arterial MACD procedures performed first time, with no perioperative complications, revisions, or thrombosis, was 88.9% (569/640). Grading of Recommendations, Assessment, Development and Evaluation (GRADE) quality analysis revealed low quality and significant heterogeneity. The use of arterial MACD is a safe and efficient alternative to hand-sewn anastomosis, with more recent literature showing excellent results. However, further evaluation is required with controlled trials.

Non-suturing microvascular anastomosis in maxillofacial reconstruction- a comparative study

AIM

The aim of the study is to compare the advantages and disadvantages of non-suturing anastomotic methods over conventional microsuturing for microvascular venous anastomosis.

MATERIALS AND METHODS

All patients reporting to the institute for hard and soft tissue reconstruction (Primary/secondary) were enrolled in the study. Patients with systemic comorbidities, peripheral vascular diseases, or anatomical aberration of the indicated donor site were excluded from the study. The patients selected for the study were randomly allocated to five groups of different techniques of venous anastomosis, namely Group I (conventional microsuturing), II (fibrin sealant reinforced microsuturing), III (couplers), IV (staplers), V (Laser Assisted Vascular Anastomosis (LAVA)). Intraoperative anastomotic time, flap ischaemic time, patency and leakage were the parameters that were assessed for all five groups.

RESULTS

80 Patients were randomly allocated to five groups and each group comprised 16 patients. The mean ischaemic time and standard deviation of Group I and Group II were 256.19 ± 10.622 min and 255.19 ± 11.083 min, and for groups III, IV, and V were 193.38 ± 9.972 min, 139.06 ± 6.413 min, and 139.31 ± 6.364 min respectively (p < 0.001). Mean anastomotic time and standard deviation were 19.813 ± 1.5366 min in Group I and 20.281 ± 1.6514 min in Group II. The non-sutured anastomosis groups III, IV, and V showed a mean anastomotic time of 5.375 ± 0.9876 min, 4.175 ± 0.7664 min, and 3.856 ± 0.867 min respectively (p value < 0.001). In Groups I and II, 18.8% of patients had delayed patency and in Groups III, IV and V, immediate patency was observed in all subjects (p value 0.030). In Groups I and II, 18.8% and 6.3 % of patients respectively had leakage, whereas all patients in Groups III, IV, V had no leakage from the anastomotic site (p value 0.119).

CONCLUSION

Based on the results of the study, non-suturing techniques should be preferred over microsuturing technique whenever appropriate for venous anastomosis.

Rapid M1 Hemoclips Arteriotomy Repair After Emergency Coil Embolectomy

BACKGROUND

The vascular closure staple clips have been studied in animal models and shown to have comparable results with sutured repair when it comes to the healing process, degree of vessel narrowing, and risk of thrombosis. However, they are clearly superior when the speed of application is taken into account, and they were clinically used in many vascular repair processes. Nevertheless, their usefulness in intracranial vascular surgery has not been described.

OBJECTIVE

To describe the usefulness of hemoclips in fast and efficient repair of medium-sized and large intracranial vessels.

METHODS

Two female patients diagnosed with giant symptomatic cavernous sinus aneurysms were undergoing elective endovascular procedures that were complicated by the dislodgement of coils into the M1 segment of the middle cerebral artery. Both patients were treated performing M1 arteriotomies and coil embolectomy. To avoid prolonged temporary occlusion in the M1 perforator's territory, the arteriotomies were repaired using microhemoclips in less than 10 min with re-establishment of flow.

RESULTS

In both patients, flow was re-established in the M1 segments. In 1 patient, the coils extended to the temporal M2 causing intimal injury and leading to diminished flow. M1 segments in both patients were patent on later angiographic studies.

CONCLUSION

We describe the advantage of emergent cerebrovascular arteriotomy and embolectomy in a rapid repair process that helped avoid massive ischemic injury. We believe this technique should be added to the armamentarium of neurosurgical cerebrovascular options.

Anastomosis with fish-mouth technique using fibrin glue

Researchers have made numerous attempts to shorten anastomosis duration since Jacobson first used the term microvascular surgery in 1960. However, none of these alternatives has its combination of facility, low cost, reliability, durability, and high success rate. This study aimed to shorten the anastomosis duration, especially in operations that require multiple anastomoses, and the authors performed experimental anastomoses with the fish-mouth technique using fibrin glue. This technique first involves 2 longitudinal incisions made 180 degrees apart in the shape of a fish mouth at each vessel end, thus creating a pair of equal-sized, full-thickness flaps on both vessels. These incisions, equal in length, were as long as the radius of the vessel. Two simple stay-sutures placed on the corners of the flap bases and vessels were approximated. Then, the anastomosis site was sealed with fibrin glue. Both control and experimental groups are consisted of 32 rats. This study assessed and statistically evaluated the groups with biopsies on days 3, 7, 14, and 21 and also assessed patency rates, microaneurysm formation, histologic healing patterns, and operation duration. The present study concluded that anastomosis with fish-mouth technique using fibrin glue takes less time, requires fewer sutures, decreases the amount of foreign materials in direct contact with the blood stream, creates less foreign-body reaction in the vessel wall, and everts contact surfaces. With these advantages, this technique provides a reliable and successful alternative, especially in operations requiring multiple anastomoses.

Five years' world experience with nonpenetrating clips for vascular anastomoses

BACKGROUND

A new sutureless technique has been introduced clinically to facilitate the process of vascular reconstruction and improve patency. The Vessel Closure System (VCS) is nonpenetrating, creates an elastomeric everted anastomosis, and is easily and reproducibly applied. The objective of this report is to review the published world experience that has accrued regarding these clips with attention to the assets, liabilities, and pitfalls associated with the new technology.

DATA SOURCES

Medline search and manual cross-referencing were performed, after which 61 original articles were identified on the use of VCS clips for vascular anastomoses.

RESULTS

Advantages of the clips compared with sutures include the technical ease of application, the reduced anastomotic time, the superior hemodynamics, and the improved healing pattern of the anastomosis. Disadvantages include the potential problems in atherosclerotic vessels, lack of prospective randomized long-term follow-up, and initial costs. The best clinical results have been achieved in microvascular repair, as well as with vascular access and transplantation surgery.

CONCLUSIONS

The VCS clip technology has become an accepted vascular anastomosing technique, which in future could lead to the use of clips as a standard approach and the use of sutures only in case of severe atherosclerosis and other circumstances in which vessel edges are difficult to evert.

Clinical experience with non-penetrating vascular clips in free-flap reconstructions

To date, the gold standard for performing a microvascular anastomosis has been the penetrating suture with attached needle. During the last two decades, non-penetrating techniques have been introduced, including the Unilink system for end-to-end anastomoses, and the VCS clip-applier system for both end-to-end and end-to-side anastomoses. The aim of this study was to compare the results of different techniques used to create microvascular anastomoses in free-flap reconstructions. Between January 1995 and October 1999, we performed 474 microvascular anastomoses in 216 consecutive free-tissue transfers. The anastomosis techniques included manual sutures (42%), Unilink rings (34%) and VCS clips (24%). Seven combined sutured-clipped anastomoses were excluded from further analysis. The mean anastomotic time when rings were applied was significantly shorter than when using clips (P 0.0001) or sutures (P 0.0001). Venous anastomoses using clips took less time than those using sutures (P 0.05). There were 19 anastomotic failures, all of which lead to early flap failure. Ten flaps were salvaged by early reoperation; nine flaps were lost. Three more flaps were lost as a result of other causes, bringing the flap survival rate down to 94.4%. Early flap failure was caused by failure of the arterial anastomosis in eight cases; all of them were sutured (these represented 5% of all arterial anastomoses with sutures). None of the clipped arterial anastomoses failed. Early flap failure was caused by failure of the venous anastomosis in 11 patients. Three of these anastomoses were sutured (representing 6% of all venous anastomoses with sutures), seven were anastomosed with rings (representing 5% of all venous anastomoses with rings) and one was clipped (representing 2% of all venous anastomoses with clips). Both the VCS clip-applier system and the Unilink system are easy to handle and allow fast microvascular anastomoses without intraluminal penetration. The patency rate of clipped vessels is at least as good as the patency rates of vessels anastomosed using sutures or rings.

Vascular closure staples-a new technique for biliary reconstruction: prospective randomized comparison with manual suture in an animal model

BACKGROUND

In orthotopic liver transplantation the incidence of biliary complications is up to 49%. In view of the relative frequency of such complications despite seemingly good preconditions, method-related disadvantages of conventional suture must also be considered as a possible cause. These include perforating needle injury of the choledochal wall with at least temporary exposure of suture material in the lumen, suboptimal approximation of the mucosa, and an additional decrease in blood flow in the choledochal stumps as a result of suture-related tissue strangulation. Hence the search for alternative anastomosis techniques.

METHODS

To evaluate the surgical suitability of extramucosal titanium clips (Vascular Closure Staples; VCS) in comparison with conventional manual suture, a study was performed in 36 pigs, which were randomly assigned to 4 groups, each containing 9 animals. Choledochal excision was performed in 18 pigs and transection in the other 18 pigs; end-to-end anastomosis was then carried out, using a VCS stapler in half of the animals in each of these two groups and conventional manual suture in the other half. Pre- and postanastomotic blood flow was measured during the surgery with the aid of a laser Doppler flow meter. The long-term behavior of the closure techniques was ascertained by regular laboratory checks over the ensuing 6-month observation period, after which the pigs were killed so that the specimens could be harvested.

RESULTS

Using medium-sized VCS clips, we were able to create a tension-free, everted biliary anastomosis with exact mucosal approximation and no narrowing of the lumen, and without any technical problems during the performance of the procedure. Measurements with the laser Doppler flow meter showed well-preserved anastomotic blood flow after clip reconstruction, with significantly higher perfusion values than after manual suture. The postoperative courses of the investigated laboratory parameters did not reveal any significant differences between the two methods. In contrast, histomorphometric evaluation showed wall thickness and thus fibrosis in the anastomosis region to be less in the clip group than in the suture group (median: 510 microm versus 660 microm, P<0.001). In the pigs in which clip anastomosis was used, there were no detectable anastomotic stenoses; in the pigs in which conventional suture was used, however, ultrasonography revealed five anastomoses with varying degrees of narrowing.

CONCLUSIONS

Extramucosal VCS clip anastomosis not only offers potential advantages with respect to nonpenetrating and optimal mucosal contact, investigations in animals also show it to be superior to conventional manual suture as regards anastomotic blood flow and medium-term fibrosis formation. We believe that our data and the available literature warrant a clinical evaluation of this technique in appropriate studies.

Lower extremity microsurgical reconstruction

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the indications for the use of free-tissue transfer in lower extremity reconstruction. 2. Understand modalities to enhance the healing and care of soft tissue and bone before free-tissue transfer. 3. Understand the lower extremity reconstructive ladder and the place of free-tissue transfer on the ladder. 4. Understand the specific principles of leg, foot, and ankle reconstruction. 5. Understand the factors that influence the decision to perform an immediate versus a delayed reconstruction. Free-tissue transfer using microsurgical techniques is now routine for the salvage of traumatized lower extremities. Indications for microvascular tissue transplantation for lower extremity reconstruction include high-energy injuries, most middle and distal-third tibial wounds, radiation wounds, osteomyelitis, nonunions, and tumor reconstruction. The authors discuss the techniques and indications for lower extremity reconstruction.

Arcuate-legged nonpenetrating vascular closure staples (VCS): early experience

Vascular closure staples (VCS) provide a novel technique for fashioning vascular anastomoses, allowing a single operator to perform suture-less anastomoses. They may be used primarily or in an adjuvant role. When VCS are compared to a running suture, advantages include the avoidance of intimal damage, platelet aggregation and intimal hyperplasia at the anastomotic suture line, and a shorter time taken to complete the anastomosis. We report our early experience using VCS in an array of vascular anastomoses and conclude that VCS are a useful addition to the vascular surgeon's armamentarium. They help to decrease the time taken to construct an anastomosis, and are particularly useful in an adjuvant setting, complementing conventionally placed sutures.

Patency and flow characteristics using stapled vascular anastomoses in dialysis grafts

BACKGROUND

Improving patency of hemodialysis grafts is challenging. Vascular stapling creates nonpenetrating anastomoses, possibly decreasing intimal hyperplasia. We investigated patency and flow characteristics of stapled hemodialysis grafts.

METHODS

Eighty-six grafts (41 stapled, 45 sewn) were placed in 84 patients (prospective, randomized). The groups had comparable demographics.

RESULTS

Thirty-six grafts were functioning at the study endpoint. Complications in both groups were similar. The primary patency (stapled, 342 days versus sewn, 382 days; P = 0.67) and secondary patency (stapled, 513 days versus sewn, 507 days; P = 0.76) had no significant differences. Flow characteristics were similar between the groups. Thrombectomies per patient-year were 1.01 for stapled grafts and 1.12 for sewn grafts (not significant). Stapling decreased the average operating time by 4.5 minutes.

CONCLUSIONS

Stapled and sewn anastomoses have similar primary and secondary patency and flow characteristics, with minimal operative time differences. Stapled anastomoses are safe but had no advantage over sewn anastomoses in this study.