Anastomosis In Free Tissue Transfer Research Articles

Distally based V-flap on the artery in an end-to-side anastomosis for arteriovenous fistula creation – A randomized controlled pilot study

With an increasing number of chronic kidney disease (CKD) patients presenting at a young age, it is necessary to create a vascular access (VA) that is reliable, long-lasting, and has minimal complications. Despite improvements in anastomotic techniques, distal arteriovenous fistula (AVF) has a high failure rate. The successful use of a geometric design for the end-to-side anastomosis in free tissue transfer led us to consider whether V-flap technique can be employed to achieve consistent and earlier maturation in distal AVF and reduce the failure rates. This was a prospective randomized controlled trial conducted between January and April 2022. Twenty CKD patients were randomized into two groups and underwent AVF creation using the slit-arteriotomy and the V-flap technique. Postoperative follow-up was performed on the 1st, 2nd, 4th, 6th, and 8th weeks. Cross-sectional area (CSA) and circumference of vein, linear and volumetric flow across the anastomosis, and the time taken to achieve AVF maturation were analyzed. There was a significant increase in the CSA and circumference in the V-flap group as compared to that in the slit-arteriotomy group. The volumetric flow across the anastomosis in the V-flap group was significantly higher than that of the slit-arteriotomy group. The median time to achieve AVF maturation in the slit-arteriotomy group was 8 weeks, whereas it was 4 weeks in the V-flap group. The V-flap technique creates an anastomosis with a greater CSA facilitating larger volumetric flow rate. This helps to achieve a consistent, reliable, and earlier maturation with successful initiation of hemodialysis.

Systematic review of microvascular coupling devices for arterial anastomoses in free tissue transfer.

BackgroundCoupling devices have become commonplace in performing venous anastomoses during microvascular free tissue transfer (FTT). However, arterial anastomoses are still most commonly performed using traditional microvascular suture techniques.ObjectiveTo describe the safety and feasibility of using microvascular coupling devices for free flap arterial anastomosis.MethodsA systematic review of English language literature was performed for studies that investigated the use of an arterial coupler for microvascular FTT in human patients. A comprehensive search of MEDLINE (January 1948 to August 2018), EMBASE (January 1974 to August 2018), and Web of Science was performed.ResultsFifteen studies were included. All studies were retrospective case series. A combined total of 395 arterial anastomoses were attempted with a coupling device. All studies except for one used the 3M Unilink/Synovis coupling device. One study used a novel absorbable coupling device. The coupling device was aborted and converted to a suture technique in 8.4% of attempted anastomoses. Rupture of the anastomotic device was reported in only 1 patient (0.3%). Thrombosis was also infrequent at 1.9%. The quality assessment showed a high risk of bias in all studies.ConclusionIn selected patients, coupling devices for arterial anastomoses have a good success rate with low rates of thrombosis based on limited quality evidence.

Use of a biopsy punch for end-to-side anastomosis in free-tissue transfer

Background: In end-to-side vessel-anastomoses, a side fenestration should be made by a slit incision or partial excision of the vessel wall. However, a slit incision might restrict blood flow across the anastomosis, and a partial vessel wall excision using micro-scissors may be time-consuming and result in irregular edges, which may weaken the vessel wall and cause flow disturbances. We used a biopsy punch for end-to-side anastomosis, and obtained satisfactory results.Methods: Between September 2015 and August 2017, 27 end-to-side anastomoses using punch biopsies were performed. Two vessel clamps were applied to the recipient vessel proximal and distal to the point planned for the side anastomosis. The flap side vessel size was measured, and an appropriately sized punch was selected. The clamped recipient vessel was supported by a wooden tongue depressor and the punch was applied to the vessel wall. An end-to-side anastomosis was performed in the usual manner, and immediate patency was tested with a refill test.Results: The vessel patency rate was 96 percent. The mean arteriotomy or venotomy time was 65 s and entire anastomosis procedure time was 1065 s. Both the vessel preparation and the micro-anastomosis procedure times were shorter than those of the conventional procedure group with statistical significance. (p < .05) There was only one case of venous failure by deep vein thrombosis – and it was resolved with thrombectomy and re-anastomosis.Conclusion: Use of a biopsy punch in end-to-side anastomosis can offer a uniform circular edge and reduce operating time.

Reply: Matched Comparison of Microsurgical Anastomoses Performed with Loupe Magnification versus Operating Microscope in Traumatic Lower Extremity Reconstruction

Background Although the surgical microscope remains the most common tool used for visual magnification for microsurgical anastomoses in free tissue transfer, loupe-only magnification for free flap breast reconstruction has been demonstrated to be safe and effective. To evaluate the loupe-only technique in lower extremity free flap reconstruction, the authors compared perioperative outcomes between microsurgical anastomoses performed with loupe magnification versus a surgical microscope. Methods The authors conducted a two-institution retrospective study of soft-tissue free flaps for traumatic below-knee reconstruction. Optimal subgroup matching was performed using patient age, defect location, flap type (muscle versus fasciocutaneous), and time from injury (acute, 30 days) for conditional logistic regression analysis of perioperative outcomes. Results A total of 373 flaps met inclusion criteria for direct matched comparison of anastomoses performed with loupe magnification (n = 150) versus a surgical microscope (n = 223). Overall major complication rates were 15.3 percent: take-back for vascular compromise, 7.8 percent; partial flap failure, 7.8 percent; and total flap loss, 5.4 percent. No differences were observed between the loupe and microscope groups regarding major complications (14.0 percent versus 16.1 percent; OR, 0.78; 95 percent CI, 0.38 to 1.59), take-back for vascular compromise (5.3 percent versus 9.4 percent; OR, 0.51; 95 percent CI, 0.19 to 1.39), any flap failure (13.3 percent versus 13.0 percent; OR, 1.21; 95 percent CI, 0.56 to 2.64), partial flap failure (7.3 percent versus 8.1 percent; OR, 1.04; 95 percent CI, 0.43 to 2.54), and total flap loss (6.0 percent versus 4.9 percent; OR, 1.63; 95 percent CI, 0.42 to 6.35). Conclusions Perioperative complication rates, take-backs for vascular compromise, partial flap losses, and total flap failure rates were not significantly different between the matched loupe and microscope groups. Overall microsurgical success rates in traumatic lower extremity free flap reconstruction appear to be independent of the microsurgical technique used for visual magnification. Clinical question/level of evidence Therapeutic, III.

Matched Comparison of Microsurgical Anastomoses Performed with Loupe Magnification versus Operating Microscope in Traumatic Lower Extremity Reconstruction

Although the surgical microscope remains the most common tool used for visual magnification for microsurgical anastomoses in free tissue transfer, loupe-only magnification for free flap breast reconstruction has been demonstrated to be safe and effective. To evaluate the loupe-only technique in lower extremity free flap reconstruction, the authors compared perioperative outcomes between microsurgical anastomoses performed with loupe magnification versus a surgical microscope. The authors conducted a two-institution retrospective study of soft-tissue free flaps for traumatic below-knee reconstruction. Optimal subgroup matching was performed using patient age, defect location, flap type (muscle versus fasciocutaneous), and time from injury (acute, <30 days; remote, >30 days) for conditional logistic regression analysis of perioperative outcomes. A total of 373 flaps met inclusion criteria for direct matched comparison of anastomoses performed with loupe magnification (n = 150) versus a surgical microscope (n = 223). Overall major complication rates were 15.3 percent: take-back for vascular compromise, 7.8 percent; partial flap failure, 7.8 percent; and total flap loss, 5.4 percent. No differences were observed between the loupe and microscope groups regarding major complications (14.0 percent versus 16.1 percent; OR, 0.78; 95 percent CI, 0.38 to 1.59), take-back for vascular compromise (5.3 percent versus 9.4 percent; OR, 0.51; 95 percent CI, 0.19 to 1.39), any flap failure (13.3 percent versus 13.0 percent; OR, 1.21; 95 percent CI, 0.56 to 2.64), partial flap failure (7.3 percent versus 8.1 percent; OR, 1.04; 95 percent CI, 0.43 to 2.54), and total flap loss (6.0 percent versus 4.9 percent; OR, 1.63; 95 percent CI, 0.42 to 6.35). Perioperative complication rates, take-backs for vascular compromise, partial flap losses, and total flap failure rates were not significantly different between the matched loupe and microscope groups. Overall microsurgical success rates in traumatic lower extremity free flap reconstruction appear to be independent of the microsurgical technique used for visual magnification. Therapeutic, III.

Protocol for a systematic review of venous coupler devices versus hand-sewn anastomosis for microsurgical free flap reconstruction

BackgroundA patent microvascular anastomosis is of paramount importance in free tissue transfer. Anastomotic coupler devices provide an alternative to technically demanding hand-sewn venous anastomosis. Various advantages of these devices have been discussed but previous systematic reviews had methodological flaws or did not perform a meta-analysis. This review aims to evaluate the quality of the evidence and quantify the efficacy and safety of venous couplers compared to hand-sewn anastomosis.MethodsA PRISMA-compliant systematic review and meta-analysis will be performed. A comprehensive search strategy has been developed and will be applied to the databases MEDLINE and Embase from inception to October 2018. All clinical studies using anastomotic coupler devices for venous anastomoses in free tissue transfer will be eligible for inclusion. Screening of studies and data extraction will be performed independently by two authors. Our primary outcome is anastomotic venous thrombosis. Secondary outcomes will include time to complete the venous anastomosis, tearing of veins, anastomotic leakage, flap loss/failure and fiscal outcomes. The risk of bias for included studies will be assessed by using the ROBINS-I tool, and recommendations based on the evidence will be made using the GRADE approach. Descriptive statistical analyses will be used and if two or more studies report the same outcome, data will be pooled for comparative analysis. A direct comparison meta-analysis will be performed if possible.DiscussionThere has been no comparison of coupled and hand-sewn venous anastomoses using a robust and validated methodology preceded by a protocol and performing meta-analysis. Included studies are expected to be mainly observational and prone to bias; however, there is value in summarising the evidence, assessing its risk of bias and performing meta-analysis to guide clinicians. By using a broad approach including all types of flaps, we foresee inherent differences regarding the unit of analysis and different anatomic sites. This will limit the validity of our conclusions but is unavoidable. We will seek unpublished data from authors and perform subgroup analysis where appropriate. Limitations and areas of uncertainty will be discussed to guide future research.Systematic review registrationPROSPERO CRD42018110111

P26 The utility of coupler devices for arterial anastomosis in free tissue transfer

Introduction Microvascular free-tissue transfer remains a reliable method for head and neck reconstruction particularly when dealing with extensive oncological resection. The microvascular anastomosis is a technically sensitive and critical determinant of success in free-tissue transfer. In Europe hand-sewn anastomosis is widely used, especially for the arterial anastomosis. Our hypothesis is that anastomotic-coupling devices offer a reliable and efficient alternative to hand-sewn anastomosis. Material and methods We performed a retrospective analysis of 68 patients who underwent a head and neck tumor resection and free-tissue transfer using the coupling system for the venous and arterial anastomosis between 2010 and 2014. Results Within the first three years (2010–2012) there were performed 37 forearm flap transplantations, three flap failures (8.1%) occurred (three venous thrombosis, no arterial thrombosis). Between 2013 and 2014 a total of 31 forearm flap transplantations were performed. Only in one patient an arterial thrombosis occurred (3.2%), thus we saw in total one flap failure. Regarding the total group (68 patients), we saw one arterial thrombosis. That is a ratio of 0.14%. This is a thrombosis rate rather similar to those reported in literature for coupled arterial anastomosis. Conclusion Regarding the decreased flap failure rate in 2013 and 2014 there is a learning curve performing microvascular free tissue transfer. After a certain experience of the surgeon the coupling system is a reliable, efficient and faster method for microvascular arterial anastomosis. Beside our own experiences the metaanalysis of Amandeep et al. shows similar results using the coupling system for arterial anastomosis. This metaanalysis included twenty-five studies with a total of 3207 patients. There were performed 342 arterial coupled anastomosis, 12 arterial thrombosis occurred (3.6%). The thrombosis rates were similar to those performing hand-sewn arterial anastomosis and coupling time was shorter. Therefore we recommend using the coupling system likewise for the arterial microvascular anastomosis.

Analysis of service provision for patients with nail bed injuries

s / International Journal of Surgery 12 (2014) S13eS117 S71 referenced to PACS Radiology reports to determine: FNAs performed by radiologists and/or ultrasound-guidance; diagnostic sufficiency and reasons for inadequacy. Results: 104 FNAs were carried out on 89 patients 74% for melanoma and 21% for squamous cell carcinoma primaries. 38% of FNAs were in the head and neck region, 31% axillary, and 27% in the groin. Surgeons performed 58%, of which 37% were ‘unsatisfactory for diagnosis’, versus 25% of those by radiologists. Anatomical region did not influence rates of unsatisfactory specimens. 36% of unsatisfactory specimens were acellular/hypocellular, whilst 12% were poorly preserved. Conclusions: Radiologist-performed FNA ismore likely to be diagnostic, but delays and costswill be incurred to access this service.We are piloting a local training program to increase the diagnostic yield of surgeon-performed FNA. 1160: ANALYSIS OF SERVICE PROVISION FOR PATIENTS WITH NAIL BED INJURIES Zita Jessop , Matthew Gardiner, Sonya Gardiner, Neil Toft. Royal Free Hospital, London, UK. Introduction: Although viewed as minor procedures, nail bed repairs take up a significant amount of time and resources. Our aim was to assess service delivery from referral to discharge. Methods: This was a retrospective review of patients with nail bed injuries identified by hospital episode statistics. Data was collected on delays in treatment, financial performance, and patient reported outcomes via a telephone questionnaire. Results: Over one month 62 of 310 hand trauma cases underwent nail bed repair. Patients were seen in trauma clinic one day after referral, waited two days (0-4days) for an operation and 6 days for a follow up clinic (012days), attending 2.6 appointments. We had a 32% questionnaire response rate; 11% of appointments were not attended, most common reason being inability to get time off work and main suggestion was reducing waiting time for an operation. Two cases were performed in clinic and 11 were coded wrongly resulting in a lower tariff estimated to cost the department £36,000 per year. Conclusions: The data formed the basis of a business case for introducing an outpatient minor operating theatre which will streamline service provision and increase available theatre time. 1172: FEASIBLE, EFFECTIVE AND EFFICIENT; THE MICROVASCULAR COUPLER DEVICE FOR END-TO-SIDE VENOUS ANASTOMOSIS IN FREE TISSUE TRANSFER FOR HEAD AND NECK RECONSTRUCTION Jane Maraka , Nigel Abreo, Omar Hausien, Nakul Patel, Amer Durrani. Addenbrookes Hospital, Cambridge, UK. Introduction: The use of a microvascular coupling device (MCD) for venous anastomosis in free tissue transfer (RTT) in head and neck reconstruction (HN University of Edinburgh, Edinburgh, UK; National University of Singapore,

Feasible, effective and efficient; the microvascular coupler device for end-to-side venous anastomosis in free tissue transfer for head and neck reconstruction

Feasible, effective and efficient; the microvascular coupler device for end-to-side venous anastomosis in free tissue transfer for head and neck reconstruction

An old controversy revisited-one versus two venous anastomoses in microvascular head and neck reconstruction using anterolateral thigh flap

The necessity of a second venous anastomosis in free tissue transfer is controversial. We review a single surgeon's 8-year experience of head and neck reconstruction using free anterolateral flap reconstruction to assess the need for a second venous anastomosis. Three hundred and fifteen cases were included in the study after selecting only for anterolateral thigh flap, head, and neck reconstruction, and those that used superior thyroid artery as recipient. The selection criteria were designed to create as homogeneous a group as possible to decrease confounding factors. The group with single anastomosis required more frequent take-backs than the group with dual anastomoses (19% vs 10.8%, P = 0.055). The trend persisted when only take-backs for venous insufficiencies were compared (8.2% vs 2.5%, P = 0.039). When flaps with single anastomosis developed venous congestion, they were more likely to require operative salvage for venous insufficiency than those with dual anastomoses (35.5% vs. 6.3%, P = 0.037). No difference was found in postoperative complications and flap survival. Our data suggest that flaps with single venous anastomosis are more likely to require take-back for flap salvage than those with dual anastomoses.

Comparative Study of Different Combinations of Microvascular Anastomosis Types in a Rat Vasospasm Model: Versatility of End-to-Side Venous Anastomosis in Free Tissue Transfer for Extremity Reconstruction

Comparative Study of Different Combinations of Microvascular Anastomosis Types in a Rat Vasospasm Model: Versatility of End-to-Side Venous Anastomosis in Free Tissue Transfer for Extremity Reconstruction

Comparative Study of Different Combinations of Microvascular Anastomosis Types in a Rat Vasospasm Model: Versatility of End-to-Side Venous Anastomosis in Free Tissue Transfer for Extremity Reconstruction

There have been many studies comparing the patency rates of end-to-end and end-to-side microvascular anastomoses in both arteries and veins. Most of them failed to demonstrate a significant difference. The purpose of this study was to compare three different combinations of microvascular anastomoses in a rat vasospasm model, and determine which type of anastomosis is the most tolerant to vasospasm. Ninety Wistar rats were divided into three groups (n = 30 for each). In each group, a free pectoral skin flap was elevated and microsurgically transferred to the anterior cervical region. In group 1, end-to-end anastomoses were performed on both arteries and veins, in group 2 end-to-side anastomoses were performed on arteries and end-to-end anastomoses were performed on veins, and in group 3 end-to-end anastomoses were performed on arteries and end-to-side anastomoses were performed on veins. After revascularization, vasospasm was induced with topical epinephrine. Flap survival was assessed on day 3, and the success rates of the three groups were compared. The flap success rate was 73.3% (22 of 30) in group 1, 66.7% (20 of 30) in group 2, and 96.7% (29 of 30) in group 3. The differences between groups 1 and 3 and between groups 2 and 3 were statistically significant. Overall, venous thrombosis was much more frequent than arterial thrombosis. In a rat epinephrine-induced vasospasm model, venous thrombosis was much more frequent than arterial thrombosis. The type of arterial anastomosis did not affect the success rate, but end-to-side venous anastomosis had a higher success rate than end-to-end venous anastomosis.

Arterial Coupling for Microvascular Free Tissue Transfer in Head and Neck Reconstruction

To demonstrate the efficacy of arterial coupling. We report our experience in head and neck reconstruction with the Unilink Microvascular Anastomotic System (Synovis MCA, Birmingham, Ala). Data were collected in a consecutive series of 49 patients undergoing composite resection of head and neck tumors followed by free tissue transfer. All patient care took place at Yale-New Haven Hospital, New Haven, Conn, a university-based tertiary care facility. Forty-nine consecutive patients aged 43 to 85 years underwent a total of 50 microvascular free tissue transfers using the Unilink coupling device. There were 18 women and 31 men, and the following 3 types of flaps were performed: radial forearm (n = 36), fibula (n = 12), and rectus abdominus (n = 2). The Unilink coupling device was used in this case series. Each arterial and venous anastomosis was performed with the coupling device. Free tissue transfers were monitored clinically and outcomes were recorded. Flap survival and thrombosis of the arterial anastomoses were determined, as was median length of stay. There were no flap failures in the series. Of the 50 coupled arterial anastomoses, the predominant coupler size used was 2.5 mm in diameter. Reconstructions included 36 radial forearm, 12 fibular osteocutaneous, and 2 rectus abdominus myocutaneous free flaps. One intraoperative arterial thrombosis occurred, requiring hand-sewn anastomosis, and another pulled away from the intact coupler in a steroid-dependent patient. There were no complications related to technical performance of the coupling device. The median length of stay was 14 days. While hand-sewn anastomoses in free tissue transfer remain the preferred technique for many microsurgeons, use of the coupler is a viable alternative to sutured anastomoses.

Tobacco Smoking and Complications in Elective Microsurgery

This study assesses the risk for complications in patients who chronically smoke but who have quit in the perioperative period of an elective free-tissue transfer as compared with patients who do not smoke. A retrospective review identified 104 free-tissue transfers in 93 smokers and 58 transfers in 51 nonsmokers. The demographics, wound etiology, and recipient sites were similar in the two populations. With the exception of a higher incidence of chronic obstructive pulmonary disease (COPD) among smokers, preexisting comorbid factors also were similar. Postoperative medical complications were comparable between populations. When comparing smokers with nonsmokers, we found that anastomotic patency and flap survival were not different (95 versus 94 percent, respectively), that delayed wound healing at the recipient site was different (35 versus 24 percent), and that smokers require an additional procedure to achieve final wound closure more frequently (27 versus 12 percent, p = 0.03). These findings suggest that cigarette smokers are at increased risk for complications, not at the site of the anastomosis in free-tissue transfer, but rather at the flap's interface with the wound or overlying skin graft.