A new combined "interrupted-continuous" microvascular anastomotic technique. Experimental study and clinical application

A new combined interrupted-continuous microvascular anastomotic technique is introduced, using four interrupted stay stitches and continuous suturing in between. Its efficacy is compared with the simple interrupted and continuous techniques. Microanastomoses were performed in the femoral artery and vein of rats. The patency, anastomosis time, and blood loss from the suture line of all anastomoses were recorded. Also, the sites of all anastomoses were harvested and histologically examined for lumen stenosis, media regeneration, and endothelial lining. Experimentation findings showed 100% patency rate in all groups. The combined and the continuous techniques were significantly faster and watertight compared with the simple interrupted. The only difference in pathology findings was the development of significant lumen stenosis in vein anastomoses performed with the continuous technique, compared with the other two techniques. The combined technique was clinically used in 16 free flap transfers and ensured 100% patency in all arterial and vein anastomoses, as well as survival of all flaps. In conclusion, the combined technique was found to be fast and easy to perform and ensured the same patency rate as the simple interrupted and continuous techniques. It also diminished the lumen stenosis effect of the continuous technique in vein anastomoses. Therefore, we suggest its use in both experimental studies and clinical cases.     

A new technique for microvascular anastomosis: eversion with 3 horizontal mattress sutures

In our experimental study of a new microvascular anastomosis technique, we divided 30 Wistar albino rats into 2 groups. We performed the classic interrupted suture anastomosis technique in group 1 (n = 15) and our new technique, using 3 horizontal mattress sutures, in group 2 (n = 15). We checked patency immediately following anastomosis, at the end of the first hour, and at the end of the third week postanastomosis. While the patency rates for both techniques were 100% at the end of the first hour, the respective values were 100% and 93.4% by the end of the third week. Using light microscopy, lumen patency, intimal and medial damage, inflammation, and granulation were evaluated histopathologically. The mean anastomosis time for the experimental group (15 minutes) was shorter than that for the classic group (mean 21 minutes), and the difference was statistically significant (P < 0.01), while the difference between the patency rates was not significant (P = 0.05). Therefore, provided that the incisions are made correctly, our microvascular anastomosis technique using 3 horizontal mattress sutures can be used in experimental and clinical studies.     

From simple interrupted to complex spiral: a systematic review of various suture techniques for microvascular anastomoses

Accomplishing successful microvascular anastomoses is undoubtedly one of the most critical steps in performing free tissue transfer. However, the ideal technique has often been a subject of debate. Therefore, our objective was to review the current literature in an attempt to find objective evidence supporting the superiority of one particular technique. A PubMed and OVID on-line search was performed in November 2007 using the following keywords: microvascular anastomoses, microsurgical anastomosis, continuous suture, interrupted suture, mattress suture, and sleeve anastomosis. Our literature review found no difference in short- and/or long-term patency rates between the six main published techniques, which includes continuous suture, interrupted suture, locking continuous, continuous horizontal, horizontal interrupted with eversion, and sleeve anastomoses. These findings were consistent for each technique as long as the microsurgeon maintained standard microsurgical principles and practice, including suture line eversion, minimized tension, and direct intima-to-intima contact. Current literature supports no overall statistical difference in short- and/or long-term patency rates between any of the various techniques. The choice to perform one suture technique over another ultimately depends on the plastic surgeon's preference and microsurgical experience. To date, there are no human randomized, controlled clinical trials comparing the efficacy and clinical outcomes of each of the various suture techniques, and therefore one's comfort and familiarity should dictate his or her microsurgical technique. However, "exposure to many and mastery of one" simply provides the plastic surgery resident, fellow, or staff the technical flexibility needed for less-complicated surgical planning when performing free tissue transfer.     

End-to-end microvascular anastomosis in the rat carotid artery using continuous horizontal mattress sutures

This paper reports a continuous horizontal mattress suture technique with advantages such as decreased time for anastomosis, minimized anastomotic leakage, eversion around the vessel edges, and other advantages which the continuous anastomosis technique has. This technique was compared with the classical interrupted and classical continuous suture techniques on a total of 59 Sprague-Dawley rat common carotid arteries: Group 1 (n = 19), interrupted suture technique; Group 2 (n = 20), standard continuous technique, and Group 3 (n = 20), continuous horizontal mattress technique. Early (30 min) and late (21 days) patency rates, anastomosis time, leakage on clamp release, oozing duration, additional sutures needed, and total number of sutures placed were statistically compared between groups. Specimens were taken at the 21st day randomly, and light microscopy (LM), scanning electron microscopy (SEM), and angiographic studies were performed. Results revealed that the continuous mattress suture technique has the advantages of providing a water-tight anastomosis with less suture materials in a shorter time, and minimal intraluminal suture material which can incite thrombosis. On the other hand, a tendency to anastomotic stricture was found to be the sole disadvantage of this technique.     

Usefulness of combined continuous suture and interrupted tie technique in hindlimb composite tissue allotransplantation in rats

According to our experience of over 100 hindlimb transplantations, in rats, catching the posterior wall with an anterior wall suture is the most common cause of thrombosis and acute transplant failure. It is generally due to inadequate visibility of the lumen and consequent blind suture placement. With an intention to find a superior suture technique, a comparative study between standard end-to-end interrupted and combined continuous sutures and interrupted tie techniques was performed. Twenty hindlimb transplantations to rats' femoral vessels were performed in each group. Anastomosis time, patency, complications, and animal and transplant survivals were compared. In the interrupted suture group (group I), anastomosis failure was encountered in one vein, with 95% of immediate patency rate. A redo of the venous anastomosis was performed and successful. The combined suture technique (group II) had 100% patency rates without complications. The average time for arterial anastomosis in groups I and II was 8.5 and 8.9 min, and for venous anastomosis, 10.7 and 9.6 min, respectively. At 2 weeks, no differences were found between groups as related to transplant and animal survival.     

Comparison of continuous and interrupted suture techniques in microvascular end-to-side anastomosis

To compare the speed and patency rates of the continuous and interrupted suture techniques in microvascular end-to-side anastomosis, 10 anastomoses utilizing each technique were performed using a femoral artery-superficial epigastric vein bypass model in Sprague-Dawley rats. The continuous suture technique was found to be almost twice as fast as the interrupted technique with no functional compromise. Patency for both techniques was 100 percent. These results are similar to those of several recent reports comparing the two techniques in end-to-end anastomosis and suggest that the continuous suture technique may be the most efficient technique for end-to-side anastomosis as well.     

Combined microvascular anastomosis: experimental and clinical experience

A short operative time and a high successful rate of microvascular anastomosis are the goals of many plastic surgeons. The authors present their experimental and clinical experience in microvascular anastomoses with the use of a combination of continuous suture and interrupted tie. Twenty rats were divided into two groups. The aorta and inferior vena cava were used for microvascular anastomoses. The vessels of 10 rats were repaired with conventional interrupted suture, and the vessels of the other 10 rats were repaired with combined anastomoses. A total of 150 clinical microvascular surgeries during the past 2 years are also presented, all of which were performed using the combined method. Microvascular anastomoses with the combined method were completed faster than when using the conventional interrupted method in experimental studies. Clinically, no direct microvascular anastomosis failed with the use of combined method. Microvascular anastomosis with the use of the combined continuous suture and interrupted tie resulted in satisfactory outcomes. This technique has the advantages of both interrupted and continuous methods, but not their shortcomings.     

Vertical mattress suture technique: an alternative vascular anastomosis

The objective of this study was to introduce the vertical mattress (VM) suture technique and compare its patency and postoperative healing with other commonly used suture techniques. Thirty-two Sprague-Dawley rats were randomly assigned to one of four suture techniques to be applied to both femoral arteries: continuous (C), interrupted (I), VM, and VM with flap (VMF) sutures. The operating time and the degree of postanastomotic leakage were recorded. The milking test was employed 5 and 15 minutes and 14 days after the operation to attain patency. Blood flow velocity was determined using ultrasonography at 1 hour and on days 1 and 14 postoperation. Rats then were sacrificed, and anastomotic lining tissues were harvested for histopathologic examination. Anastomoses by C and I were executed in 12.06 and 18.31 minutes. Modified suture techniques took longer to execute anastomosis (23.09 minutes for VM and 32.44 minutes for VMF). VM suture technique was superior to other suture techniques in terms of anastomotic leakage, quality of filling, and blood flow velocity. Also, absence of the luminal closure or constriction, intimal injury and hyperplasia, foreign body inflammation, and inversion were noted in histopathology. In conclusion, the VM suture technique could be considered for microvascular surgery.     

Absorbable polydioxanone suture for venous anastomoses: experimental studies using venography and transluminal angioscopy

Because of their increased tendency to stenosis and spasm and thrombosis, results after venous anastomoses are often unsatisfactory. Nonabsorbable sutures and a continuous suture technique have been suggested to have a negative effect on the compliance of vascular anastomoses. Eighty venous anastomoses were performed with either an interrupted or continuous suture technique, using polypropylene or polydioxanone (PDS) sutures, according to a randomised experimental model. The anastomoses were divided in four groups: (1) Nonabsorbable suture material, continuous suture technique; (2) Nonabsorbable suture material, interrupted suture technique; (3) Absorbable suture material, continuous suture technique; and (4) Absorbable suture material, interrupted suture technique. The morphology of the anastomoses was controlled by venography directly after closure of the wound and at weekly intervals for 2 months and monthly intervals thereafter until 2 years had passed. In 10 cases venography was followed by transluminal angioscopy in the early postoperative period and after 1, 2, 4, 8 and 12 weeks. In the first 2 months moderate and high degree stenoses were found in all 4 groups by venography. After 8 weeks there was a significant decrease in the incidence of stenosis in all groups with the exception of the group, in which continuous nonabsorbable suture had been used. Using angioscopy a marked swelling of the intima at the site of the anastomoses could be detected in the early postoperative period in all experimental groups. After 2 months no significant narrowing could be identified in groups 2, 3 and 4.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of anastomotic suturing techniques in the rat esophagus.

BACKGROUND: Long-gap esophageal atresia continues to be a challenging pediatric thoracic surgical problem. Despite the use of various tension relieving procedures, the esophageal anastomosis is often performed under considerable tension. Excessive tension can cause anastomotic sutures to pull through the esophageal tissue, with resultant early esophageal anastomotic dehiscence. To test the hypothesis that interrupted horizontal mattress sutures would withstand the forces of tension better than interrupted simple sutures, an experimental study of rat esophageal anastomoses was done. METHODS: Twenty rats were killed and their esophagi were excised. The esophagi were divided in the mid portion and end-to-end anastomoses were done using interrupted 6-0 polypropylene sutures. Ten rats had anastomoses done with interrupted simple sutures and ten had interrupted horizontal mattress suturing. Anastomotic breaking strength was tested in a tensiometer. RESULTS: Anastomotic breaking strength was 3.22+/-0.56 N for the interrupted simple sutured anastomoses and 3.51+/-0.61 N for the interrupted horizontal mattress group (p=0.30). The difference was not significant. CONCLUSIONS: In this animal study interrupted simple and horizontal mattress suturing withstood the disruptive forces of anastomotic tension equally well.     

Horizontal mattress technique for anastomosis of size-mismatched vessels

OBJECTIVE:

To evaluate the horizontal mattress technique in microvascular anastomosis for size-mismatched vessels.

METHODS:

The present study involved cadaveric simulation using size-mismatched (1.5:1) Thiel-embalmed cadaveric arteries. The authors performed horizontal mattress anastomoses using 9-0 nylon suture and recorded the procedure. Vessel patency was evaluated by saline infusion. Vessels were cut open and photographed; histological slides were prepared and stained with hematoxylin and eosin.

RESULTS:

Four anastomoses were performed. Vessels were found to be patent in all cases, with grade 0 leaks. Intima-on-intima apposition with no intraluminal exposure of muscularis nor adventitia were observed.

CONCLUSION:

The present cadaveric study supports the technical feasibility of using horizontal mattress sutures in size-mismatched end-toend anastomoses.     

Microsurgical vasoepididymostomy: a prospective randomized study of 3 intussusception techniques in rats

PURPOSE: Vasoepididymostomy is a technically challenging but cost-effective treatment for obstructive azoospermia. We evaluated the outcomes of 3 intussusception vasoepididymostomy techniques, namely 3 suture triangulation, 2 suture transverse and a new 2 suture longitudinal technique. MATERIALS AND METHODS: Male Wistar rats were randomized into 4 experimental and 1 control groups. After 3 weeks of vasal obstruction bilateral vasoepididymostomy was performed. In group I, 3 sutures were placed in triangular fashion. In group II, 2 sutures were placed perpendicular to the tubule. In group III, 2 sutures were placed longitudinal to the tubule. The tubules were then opened in the direction of the needles and anastomosed to the vasa. After 5 months patency was evaluated in blinded fashion. RESULTS: The functional patency rate (presence of motile sperm in the vas) was 64%, 64% and 93% in groups I to III, respectively (p <0.001). As evaluated by methylene blue retrograde vasography toward the epididymis, the mechanical patency rate was similar for the 3 techniques, that is 86%, 86% and 93% in groups I to III, respectively. The sperm granuloma rate was significantly lower in group III (36%, 21% and 0% in groups I to III, respectively, p <0.001). CONCLUSIONS: Transverse 2 suture vasoepididymostomy has a patency rate similar to that of the 3 suture technique. Our new 2 suture longitudinal technique, which allows a larger opening in the epididymal tubule for anastomosis, is superior to the 2 and 3 suture techniques with respect to the patency and sperm granuloma rates.     

Scanning electron microscopy in different techniques of microvascular anastomoses: categorization and factors affecting. A descriptive work

Many researchers have investigated microvascular anastomoses by scanning electron microscope (SEM); however, there are neither reports on classifying these anastomotic types according to the SEM results nor about studying the factors that affect these results. Sixty rat femoral arteries were anastomosed using four different techniques: simple interrupted, continuous, sleeve, and autogenous arterial cuff. The anastomotic sites of each group and other two intact femoral arteries were examined by SEM. Intimal disruption and rebuilding of the blood vessel endothelium after microvascular anastomoses depend upon anastomotic time; suture placement, either intra-luminal or extra-luminal; and mechanical factors. Accordingly, the simple interrupted suture technique has the highest degree of intimal disruption and the lowest degree of regeneration, the continuous and cuff anastomoses have better rebuilding with partial neo-endothelial coverage of the cut ends, whereas the sleeve anastomosis has the best regeneration with complete coverage of the cut ends by the new endothelial cells. Presented in the Fifth Congress of the World Society of Reconstructive Microsurgery (WSRM), Athens, Greece, June 2007.     

Bursting strength in CO2 laser-assisted microvascular anastomoses

Iliac artery end-to-end anastomoses were performed in 42 Sprague-Dawley rats, divided into seven groups, to determine the welding effects of CO2 laser radiation in microvascular anastomoses. Conventional suture techniques were performed on right iliac arteries, and left iliac arteries were anastomosed with a laser-assisted technique. Bursting strength and diameters of the anastomotic sites were measured at different intervals (from one day to five weeks) post surgery. The anastomotic patency rate was 100 percent in both groups, and the aneurysm rate was only 2 percent in the laser group. Bursting strength was low at one and three days post surgery in both groups; then, it increased gradually until both groups could withstand higher than physiologic pressures. Results of high patency rates, low aneurysm formation, and the ability to withstand pressures higher than physiologic, suggest that the laser-assisted anastomotic technique can play an important role in microvascular surgery.     

Pull out stent: A trick to improve the intravascular stenting technique

The intravascular stent technique (IVaS) was developed to simplify the anastomosis of submillimeter blood vessels. One variation of the IVaS called the “clip stent”, improved the patency of anastomosed vessels. The goal of this study was to analyze a subsequent technical variation called the “pull out stent”, which aims to reduce trauma to the vessel. Our experimental study comprised 4 groups of 10 rats. Anastomosis of the tail artery was performed with 10-0 nylon suture using either interrupted sutures (group I), IVaS (group II), “clip stent” (group III), or “pull out stent” (group IV). The “pull out stent” technique consisted of 3 steps: introduction of the stent (intraluminal and then transluminal introduction of a 4-0 nylon monofilament followed by introduction of the other end into the opposite lumen), anastomosis, and then removal of the stent. The anastomosis procedure time was longer in group III than in group IV. The number of stitches and the patency were similar in all groups. There were more leaks in group I. The “pull out stent” was faster, less traumatic to the vessel wall, allowed for more regular sutures and caused fewer leaks than the other stenting techniques. One possible clinical application is the anastomosis of digital veins as part of replantation or toe transfers, especially in children.     

Laurence’s stitch: continuous horizontal mattress suture for skin closure

Various techniques have been described for closure of surgical wounds. These include, subcuticular technique, interrupted vertical mattress, clips, etc. We report a technique of continuous horizontal mattress for skin closure using absorbable suture material. This technique is quick and easy to master, avoid gaping of wound, good cosmesis and is suitable for all wound sizes.     

Mattress anastomosis in micro vascular reconstruction: technical note

Background

Superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis is a common procedure for neurosurgeons. The surgery necessarily requires accurate and speedy manipulation of microscope, for which a specific training is needed. Unexpected bypass occlusion sometimes happen during surgery.

Objective

Generally, conventional interrupted or continuous suture has been used for vascular anastomosis, despite various ideas have been attempted in the other surgery fields. We propose a horizontal mattress suture technique for intracranial microvascular bypass surgery. This is the first report ever published on intracranial vascular anastomosis.

Methods

We had four patients of STA-MCA bypass surgery with “mattress anastomosis” from March to May of 2012.

Results

During the procedure, there was no bypass occlusion and good patency was confirmed in all cases.

Conclusion

Intimae of the recipient and the donor blood vessel contact each other precisely with this technique. Although a long-term assessment of patency is needed, it is useful for the intracranial bypass surgery.     

End-to-side-anastomosis in the dog using the 3M precise microvascular anastomotic system: a comparative study.

In this study, the patency rates, microscopic characteristics, and intraluminal dimensions of end-to-side anastomoses in the dog were compared with those of a conventional interrupted suturing technique, using the 3M precise microvascular anastomotic system. The anastomoses included end-to-side repairs of the saphenous artery to the femoral artery, as well as the saphenous vein to the femoral vein. The patency and microscopic characteristics of the two techniques were similar, but the mechanical coupling system required much less time than the suture technique to complete the vascular anastomosis.     

Evaluation of long-term patency rates of different techniques of arterial anastomosis in rabbits

The results of 160 arterial anastomoses performed with four different techniques are presented. The popliteal arteries (mean diameter 0.7 mm) of 40 rabbits in each of four groups were anastomosed using: I. End-to-end technique with assymetrical sleeving of the adventitia; II. end-to-end technique with symetrical sleeving of the adventitia and wrapping of the suture site with a collagen cuff; III. end-to-end technique with symetrical trimming of the adventitia; and IV. end-in-end technique. Long-term patency rates for the above techniques were as follows: Group I, 92.5%; Group II, 87.5%; Group III, 92.5%; Group IV, 90.0%. Group IV anastomoses were completed in an average of 15 minutes compared with an overall average of 24 minutes for the other three groups.     

A comparison of para-anastomotic compliance profiles after vascular anastomosis: nonpenetrating clips versus standard sutures

PURPOSE: Anastomotic compliance is an important predictive factor for long-term patency of small diameter vascular reconstruction. In this experimental study we compare the compliance of continuous and interrupted sutured vascular anastomoses with those using nonpenetrating clips. METHODS: Both common carotid arteries in nine goats (average weight, 57 +/- 5.7 kg) were transected, and end-to-end anastomoses were constructed with nonpenetrating clips or polypropylene sutures. The latter were applied with both interrupted and continuous techniques. Intraluminal pressure was measured with a Millar Mikro-tip transducer, and vessel wall motion was determined with duplex ultrasound equipped with an echo-locked wall-tracking system. Diametrical compliance was determined. Environmental scanning electron microscopy was performed on explanted anastomoses. RESULTS: There was a reduction in anastomotic compliance and associated proximal and distal para-anastomotic hypercompliant zones with the use of all techniques. However, compliance loss was significantly less in those anastomoses with clips and interrupted sutures when compared with continuous suture (P <.001). Furthermore, the total compliance mismatch across anastomoses with continuous sutures was significantly greater than those with clips or interrupted sutures (P <.05). The mean time for constructing clipped anastomoses was 5.7 +/- 1.4 minutes, which was significantly less than either continuous (P <.0001) or interrupted sutures (P <.0001). Furthermore, environmental scanning electron microscopy demonstrated minimal intimal damage with good intimal apposition in the clip group. CONCLUSION: Anastomoses performed with nonpenetrating clips resulted in improved para-anastomotic compliance profiles and reduced intimal damage when compared with those with polypropylene sutures. These benefits may enhance long-term graft patency by reducing the risk of anastomotic intimal hyperplasia.