Lower Extremity Free Flap Outcomes Using an Anastomotic Venous Coupler Device

The Impact of Technical Innovations and Donor-Site Mesh Repair on Autologous Abdominal-Based Breast Reconstruction-A Retrospective Analysis

Background: The aim of this study was to examine the potential benefit that may be achieved through the introduction of technical innovations and the incorporation of mesh for fascial donor site closure in uni- and bilateral autologous breast reconstruction with abdominal tissue. Methods: A retrospective single-center review of all breast reconstructions with a DIEP or MS-TRAM flap between January 2004 and December 2019 was performed. Donor and recipient site complications and operation times were evaluated before and after the implementation of coupler anastomoses, preoperative computed tomography angiography (CTA), indocyanine green (ICG) angiography, and the inclusion of mesh in donor site repair. Results: A total of 396 patients were included, accounting for 447 flaps. Operation time was significantly shorter in unilateral reconstructions after the implementation of CTA (p < 0.0001). ICG angiography significantly reduced the rates of partial flap loss (p = 0.02) and wound healing disorders (p = 0.02). For unilateral reconstructions, abdominal bulging or hernia was observed more often in MS1-TRAM flaps without synthetic mesh repair (p = 0.001), whereas conservatively treated seroma developed more frequently after mesh implantation (p = 0.03). Conclusions: Recent technological advancements developed over the past few decades have made a substantial impact on decreasing surgical duration and enhancing procedure safety.

Technical Variables in Lower Extremity Free Flap Reconstruction

BACKGROUND

 Lower extremity free flap failure rates are higher than in other areas of the body. While prior studies assessed the effect of intraoperative technical variables, these generally investigated individual variables and did not examine relationships between the many individual technical decisions made during free tissue reconstruction. Our purpose was to investigate the effect of variation in intraoperative microsurgical techniques on flap outcomes in a diverse cohort of patients requiring lower extremity free flap coverage.

METHODS

 Consecutive patients undergoing free flap reconstruction of the lower extremity at two level 1 trauma centers from January 2002 to January 2020 were identified using Current Procedural Terminology codes, followed by a review of medical records. Information regarding demographics and comorbidities, indications, intraoperative technical details, and complications was collected. Outcomes of interest included an unplanned return to the operating room, arterial thrombosis, venous thrombosis, partial flap failure, and total flap failure. Bivariate analysis was performed.

RESULTS

 In total, 410 patients underwent 420 free tissue transfers. The median follow-up time was 17 months (interquartile ranges: 8.0-37). Total flap failure occurred in 4.9% (n = 20), partial flap failure in 5.9% (n = 24), and unplanned reoperation in 9.0% (n = 37), with arterial thrombosis in 3.2% (n = 13) and venous thrombosis in 5.4% (n = 22). Overall complications were significantly associated with recipient artery choice, with arteries other than PT and AT/DP having a higher rate (p = 0.033), and with arterial revisions (p = 0.010). Total flap failure was also associated with revision of the arterial anastomosis (p = 0.035), and partial flap failure was associated with recipient artery choice (p = 0.032).

CONCLUSION

 Many interoperative options and techniques are available when performing microvascular lower extremity reconstruction that leads to equally high success rates. However, the use of arterial inflow outside of the posterior tibial and anterior tibial arteries leads to a higher overall complication rate and partial flap failure rate. Intraoperative revision of the arterial anastomosis portends poorly for ultimate flap survival.

Canadian Trends in Free Flap Management for Microsurgical Lower Limb Reconstruction

Introduction: Free tissue transfers have become a mainstay in lower limb salvage, allowing safe and reliable reconstruction after trauma, tumor extirpation, and complex wounds. The optimal perioperative (PO) management of these flaps remains controversial. This study aims to assess the current state of practice among Canadian microsurgeons. Methods: Sixty-four Canadian microsurgeons were approached to complete an online questionnaire regarding their PO management of fasciocutaneous free flaps used for lower limb reconstruction. Trends in dangling timing and duration, use of venous couplers, compressive garments, thromboprophylaxis, and surgeons' satisfaction with their protocol were assessed. Results: Twenty-eight surgeons responded. Fifty-seven percent did not have a specific mobilization protocol. Dangling was mainly initiated on postoperative days 5 to 6 (44%). The most common protocol duration was 5 to 6 days (43%). The concern for prolonged venous pooling was the main reason for delay of dangling (71%). Compressive garments were placed routinely by 12 surgeons (43%) with 20% starting before dangling, 46% with dangling, and 33% after dangling. Venous couplers were routinely used by 24 surgeons (85.7%). Trends in management were influenced by previous training in 53.6% of cases (vs evidence-based medicine 7.1%). Although 89.3% were satisfied with their approach, 92.8% would consider changing practice if higher-level evidence was available. Conclusions: The majority of Canadian microsurgeons initiate dangling early and utilize venous couplers. However, the use of compressive garments is limited. Trends in management are largely based on personal experience. Nearly all surgeons would consider changing their practice if higher-level evidence was available.

Is there a difference in venous thrombosis rate in free flap anastomoses based on coupler diameter? A systematic review. Does Size Really Matter?

Background

The adage is to use the largest anastomotic coupler device (coupler) size possible, since smaller an anastomosis might be more susceptible to thrombosis. It is unclear if this wisdom is supported by data. This study tests the hypothesis that there is no difference in the reported literature in thrombosis rate between different coupler sizes.

Methods

We searched PubMed, Embase, and the Cochrane Library. After screening 235 studies, we included 11 retrospective case-series. According to the criteria of Newcastle–Ottowa Scale, quality score ranged from 2 to 4 (out of 5) and funnel plots indicated publication bias. We included a total of 5930 coupled anastomoses. We calculated thrombosis rate per coupler diameter with exact confidence intervals (CIs). We regard non-overlapping CIs as a significant difference.

Results

Nine studies reported no difference in thrombosis rate based on coupler size. Two studies report a potentially greater thrombosis rates in smaller sizes: (1) 2.0 mm 27% (95% CI 17%–40%, 17/62 cases) vs. 3.0 mm 6.3% (95% CI 2.8%–12%, 8/126 cases) and (2) 1.5 mm 6.9% (95% CI 2.8%–14%, 7/101 cases) vs. 3.0 mm group 1.2% (95% CI 0.64%–2.1%, 13/1079).

Conclusion

There is some evidence that suggests that smaller coupler sizes are associated with greater thrombosis rate, but the current available evidence has limitations. Performing a second anastomosis, in case, the first anastomosis is performed with a coupler size of 1.0, 1.5, or even 2.0 mm, can potentially reduce this rate, however, this remains to be determined.

Vein Grafting in Microsurgical Lower Extremity Reconstruction: Outcome Analysis of Primary versus Secondary Salvage Procedures

BACKGROUND

 Many microsurgeons fear high complication rates and free flap loss when vein grafting is necessary to restore blood flow at the recipient site. The aims of this study were to comparatively analyze surgical outcomes of interposition vein grafts (VG) in microsurgical primary lower extremity reconstruction and secondary salvage procedures.

METHODS

 A retrospective study was conducted on 58 patients undergoing free flap transfers with vein grafting for primary lower extremity reconstruction (cohort 1) and secondary salvage procedures (cohort 2) between 2002 and 2016. A matched-pair analysis of both cohorts and 58 non-VG flaps was performed. Patient data, preoperative conditions, flap and vein graft characteristics, postoperative outcomes such as flap failure, thrombosis, and wound complications were analyzed.

RESULTS

 A total of 726 free flap transfers were performed. In total, 36 primary reconstructions (5%) utilized 41 interposition VG (cohort 1). Postoperative vascular compromise was observed in 65 free flaps (9%). In total, 22 out of 65 secondary salvage procedures (33.8%) utilized 26 interposition VG (cohort 2). Two total flap losses occurred in each cohort (5.6 vs. 9.1%; p = 0.63). Postoperative complications were observed in 38.9% of free flaps in cohort 1 and 72.7% in cohort 2 (p = 0.01). Takeback for microvascular compromise was comparable in both cohorts (19.4 vs. 22.7%; p = 0.75). Microvascular complications occurred more often in cohort 2 (22.7%) than in cohort 1 (8.3%; p = 0.28). Lower extremity salvage rates were high among both cohorts (94.4 vs. 90.9%; p = 0.63). Matched-pair analysis did not show any relevant differences on takebacks and flap loss (p = 0.32 and p = 1.0).

CONCLUSION

 In complex lower extremity reconstructions, VG can be performed with acceptable complication rates and outcomes in primary and especially in salvage cases. With careful planning and a consistent surgical protocol, VG can provide reliable success rates in limb salvage.

Free Flaps in Lower Extremity Reconstruction

Free tissue transfer to the lower extremity for limb salvage remains challenging. A comprehensive approach includes patient selection, flap selection, selection of the recipient vessels, flap dissection, flap preparation, microvascular anastomosis, flap inset, immediate postoperative care, intermediate postoperative care, and further follow-up care. Each step in this comprehensive approach has its unique considerations and should be executed equally to ensure an optimal outcome. Once acquired, some clinical experience along with adequate microsurgical skill, good surgical judgment, well instructed and step-by-step intraoperative execution, and a protocol-driven practice, successful free tissue transfer to the lower extremity can be accomplished.

Correlation between Venous Thromboembolism Risk and Venous Congestion in Microvascular Reconstruction of the Lower Extremity

BACKGROUND

Risk for venous thromboembolism formation and the relationship to postoperative free flap venous congestion and flap failure have not been adequately evaluated in a trauma population. The authors aim to use the Caprini Risk Assessment Model to evaluate the association between venous thromboembolism risk and postoperative flap venous congestion following lower extremity free tissue transfer.

METHODS

A retrospective analysis was conducted of all patients who underwent lower extremity free flap reconstruction of traumatic defects at a single institution between 2007 and 2016. A Wilcoxon rank sum test was used for nonparametric analysis of aggregate Caprini Risk Assessment Model scores and flap outcomes. Flap venous congestion and failure rates as associated with the categorical variables underlying the Caprini Risk Assessment Model were further studied. Logistic regression was used to evaluate each of these outcomes and other flap-related covariates relative to the Caprini Risk Assessment Model categorical variables that had the greatest effect on our patient sample.

RESULTS

One hundred twelve patients underwent lower extremity free flap reconstruction. One hundred eight free flaps were analyzed. Eight patients were excluded. The majority of patients were male (75.9 percent) and required reconstruction because of acute trauma (68.1 percent versus 31.9 percent for chronic wounds). There was no statistically significant association found between age, body mass index, or timing of trauma versus venous congestion, flap failure, or other flap-related covariates.

CONCLUSION

In patients with significantly elevated Caprini Risk Assessment Model scores, there was no significant association between venous thromboembolism risk and flap failure following free tissue reconstruction of lower extremities.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Venous Coupler in Pediatric Free Tissue Transfer: Case Series and Literature Review

Background

Venous couplers have gained widespread acceptance as an effective, safe, and time-efficient alternative for hand-sewn anastomosis in microsurgical reconstruction. The literature on venous couplers use in pediatric free tissue transfer is scant. The purpose of this study is to present our experience with coupler-assisted venous anastomosis in young pediatric free flap reconstruction.

Methods

This is a retrospective single-center review of all children younger than 10 years old who underwent free flap reconstruction over 36-month period. The primary objective was to assess flap survival rate at 30-day postoperative period. The rate of venous thrombosis, flap take back, flap salvage, and the mean coupling time were also assessed.

Results

Four girls and 1 boy with a mean age of 7.3 ± 2.7 years (range 4-10 years) underwent 6 free flap transfers for head and neck, upper limb, and lower limb reconstructions. Microvascular anastomotic coupler system was used for 8 out of 9 performed venous anastomoses with a size ranging from 1.5 to 2.5 mm. Primary flap survival rate was 100%. None of the flaps in our series developed venous thrombosis or required flap take back for microvascular compromise (mean follow-up of 14.4 months). The mean coupling time was 7.1 minutes.

Conclusions

In the current study, venous couplers were safe and reliable in free tissue transfer in children younger than 10 years old. Future studies with larger sample size are needed to further examine the safety and efficacy of venous couplers in pediatric microsurgical anastomosis.

Microvascular coupler device versus hand-sewn venous anastomosis: A systematic review of the literature and data meta-analysis

BACKGROUND

Successful vascular anastomosis is essential for the survival of free tissue transfer. The aim of the study is to review the current literature and perform a meta-analysis to assess the potential advantages of a mechanical anastomosis coupler device (MACD) over the hand-sewn (HS) technique for venous anastomoses.

METHODS

A systematic Medline search was performed to gather all reports of articles related to MACD from 1984 until now. The following data were extracted: first author and publication date, study design, number of patients and anastomosis, coupler size, site and type of reconstruction, venous anastomotic time, flap failure. A meta-analysis was performed on articles that met the following inclusion criteria: studies comparing MACD and HS technique in venous anastomosis, reporting anastomotic time, and postoperative complications.

RESULTS

Thirty-three studies were included for the analysis. Twenty-four were retrospective case series and nine were retrospective comparative studies. A total of 12,304 patients were enrolled with a mean age of 49.23 years (range 31-72). A total of 13,669 flaps were accomplished. The thrombosis rate recorded with MACD was 1.47%. The meta-analysis revealed that MACD significantly decreased anastomotic time (standard difference in means = -0.395 ± 0.105; Z = -3.776; p < .001) and postoperative flap failure risk (odds ratio [OR] = 0.362, 95% confidence interval [CI] = 0.218-0.603, Z = -3.908, p < .001), but it did not decrease postoperative venous thrombosis risk (OR = 0.504, 95% CI = 0.255-1.129, Z = -1.666, p = .096).

CONCLUSIONS

MACDs are a safe and effective alternative to traditional anastomosis. The anastomotic coupler is easier, much faster, and requires less technical skills than a HS microvascular anastomosis.

Use of venous couplers in microsurgical lower extremity reconstruction: A systematic review and meta-analysis

BACKGROUND

Free tissue transfer for lower limb reconstruction has become a workhorse procedure for limb-salvage. Compared with other recipient sites, the lower extremity has a higher risk of microvascular complications, in particular with venous anastomosis. The study's objective is to evaluate the evidence, safety, and efficacy of venous coupler use in microsurgical anastomosis in lower limb reconstruction to provide objective appraisal of the surgical techniques.

METHODS

A systematic review (SR) and meta-analysis (MA) were performed analyzing articles from PubMed, Cochrane, Embase, and Web of Science from January 1990, to August 2018. Abstracts and titles were screened and assessed for eligibility by independent reviewers. Following full-text review, articles were included in the SR and MA. Case reports were excluded. Cochrane Collaboration and the Quality of Reporting of Meta-analyses (QUOROM) guidelines were followed.

RESULTS

Out of 15 included studies that met the inclusion criteria for the SR, 9 were included in MA. Patients treated with venous couplers did not experience more surgical complications (risk ratio (RR) 0.79; 95% confidence interval (CI) 0.48-1.33; p = .38), total failure (RR 0.61; 95% CI 0.22-1.70; p = .34), venous compromise (RR 0.72; 95% CI 0.23-2.27; p = .57), arterial compromise (RR 0.85; 95% CI 0.25-2.88; p = .80), partial failure (RR 0.77; 95% CI 0.33-1.77; p = .54), or reoperation (RR 11.79; 95% CI 0.49-286.55; p = .13) in comparison with hand-sewn anastomosis.

CONCLUSIONS

Outcomes of venous couplers in lower limb reconstruction are comparable to those of hand-sewn anastomosis. However, this study was limited by the quality of the available literature. Additional prospective studies should aim to directly compare both techniques and potential further benefits in clinical trials.

Should 1 or 2 Venous Anastomoses Be Done in Microsurgical Flap Transfer?

BACKGROUND

Venous compromise is still the most common cause of free flap failure. The need of a second venous anastomosis to prevent free flap failure is controversial. It is proposed that the use of dual venous anastomoses reduces venous compromise. However, some surgeons suggest that dual venous drainage reduces venous blood flow causing a potential risk of thrombosis.

OBJECTIVE

This study aimed to compare the frequency of reexploration secondary to venous thrombosis in free flap surgeries in reconstruction of soft tissue defects with 1-vein versus 2-vein anastomosis.

MATERIALS AND METHODS

We performed a retrospective cohort study including 298 flaps. In 180 of these patients, 2-vein anastomosis was done, and in 118, 1-vein anastomosis was done. The study was conducted at Aga Khan University Hospital from January 2017 to December 2018.

RESULTS

The number of venous anastomosis was not associated with flap survival. The group with dual anastomosis required more frequent reexploration as compared with 1 venous anastomosis group (8% vs 1.7%).Outcome and salvage rate were better in the 2-vein group as compared with the 1-vein group (64% vs 50%).

CONCLUSION

There is no difference in flap survival in single or dual venous anastomosis, but we have noticed higher reexploration rates in the 2-vein group. However, outcome is better in the 2-vein group.

Free perforator flaps vs propeller flaps in lower limb reconstruction: A cost/effectiveness analysis on a series of 179 cases

PURPOSE

The aim of this report is to compare free perforator flaps and propeller flaps in the coverage of lower limb soft tissue defects.

PATIENTS AND METHODS

179 patients (age between 5 and 92 years old), underwent soft tissue reconstruction of the lower limb between January 2009 and January 2015, either by free flap or propeller flap. The two groups were retrospectively evaluated in order to assess the outcome, complications and potential risk factors. Correlations between risk factors and presence/absence of failure or complications have been evaluated with descriptive statistical analysis and a set of logistic regression models. Finally, an economic analysis was conducted to evaluate the different tecniques.

RESULTS

In a simple descriptive statistical analysis, the overall failure rate is 6% for free flaps and 3.7% for propeller flaps; the complication rates are 14% vs 21.5% and it increases as dimension increases. The logistic models relating failure and complications with potential risk factors do not show significant differences, whereas the economic analysis show that the average expense of free flaps is 5077.5€ per patient, 1595.6€ per patient for propeller flaps.

CONCLUSIONS

Our results do not demonstrate significant differences between the two groups about correlation of risk factors or flap size with complication or failure. The surgical option choice should be taken only after accurate evaluation of the soft tissue surrounding the defect. Propeller flaps should be preferred in case of small/medium size defects in otherwise healthy extremities. Free perforator flaps should be the choice in large defects due to trauma or vascular diseases. The economic analysis suggests that propeller flap should be considered when possible.

Meta-analysis of venous anastomosis techniques in free flap reconstruction

BACKGROUND

Coupler devices and hand-sewn anastomosis techniques are both routinely employed for venous anastomosis in microsurgical free flap transfer. However, uncertainty remains about whether those two techniques are different in terms of risk of venous thrombosis. The aim of this review was to evaluate the quality of the evidence and quantify the difference in venous thrombosis rates in both techniques.

METHOD

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses compliant systematic review and meta-analysis were performed according to a previously published protocol. MEDLINE and Embase databases were searched from inception to 1 October 2018. Clinical studies using coupler devices for venous anastomoses in free tissue transfer were included. The primary outcome was post-operative venous thrombosis risk. Surgical anastomosis time was a secondary outcome. The risk of bias was assessed with the ROBINS-I or NIH tool and recommendations were made using the GRADE criteria.

RESULTS

A total of 10,851 patients across 32 observational retrospective studies were included, with data available for 12,769 free flaps in breast, head and neck, limb and other reconstructions. Direct comparison meta-analysis of 7 studies showed a reduced post-operative thrombosis risk for venous coupler, although this was an imprecise estimate (RR 0.68 [95% CI 0.39-1.19]). The risk of bias was consistently high across all studies.

CONCLUSION

Venous couplers may reduce the risk of venous thrombosis, but further randomised trial data are needed to improve the accuracy of this estimate. Further research should also assess size-mismatch between donor and recipient vessel, and the influence of coupler size on outcomes (PROSPERO registration ID: CRD42018110111).

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

BACKGROUND

A 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.

METHODS

A 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.

DISCUSSION

There 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 REGISTRATION

PROSPERO CRD42018110111.

Case of late-onset, relapsing surgical site infection related to a venous coupler placed during free flap reconstruction for major head and neck cancer

BACKGROUND

Venous coupling devices are widely used during reconstructive surgery involving microvascular anastomosis but have not served as foreign bodies in head and neck surgical site infections.

METHODS

We conducted a case report.

RESULTS

A patient underwent resection and free flap reconstruction for recurrent tongue squamous cell carcinoma. She developed a neck abscess due to Streptococcus intermedius 7 weeks postoperatively, days after starting chemoradiotherapy. The surgical site infection healed with drainage and antibiotics. Two surgical site infection relapses due to S. intermedius occurred 3 and 8 weeks after completing radiation, the second relapse after a prolonged course of i.v. antibiotics. Surgical exploration revealed a venous coupler within granulation tissue. The device was removed and no further surgical site infection relapses occurred.

CONCLUSION

To the best of our knowledge, this is the first report of a delayed-onset head and neck surgical site infection in which a venous coupler served as a foreign body. An infected foreign body should be suspected in relapsing surgical site infections due to a single organism.

Magnitude of Soft-Tissue Defect as a Predictor of Free Flap Failures: Does Size Matter?

OBJECTIVES

To examine the relationship between the magnitude of soft-tissue defect and the risk of free-flap and limb-salvage complications/failures.

DESIGN

Retrospective cohort.

SETTING

Level I Trauma Center.

PATIENTS

One hundred twelve patients with free tissue transfers between January 2009 and June 2015.

INTERVENTION

A standardized approach using a consistent team of 2 orthopaedic microvascular surgeons was used for each free-flap reconstruction.

MAIN OUTCOME MEASURE

Soft tissue defect size, total or partial flap failure, and unplanned reoperations.

RESULTS

Of 112 free-flap reconstructions, 57 complications occurred in 43-cases (38%) including 5 total flap failures (4.5%), 7 partial flap failures (6%), and 8 early (7%) and 38 delayed complications (33%). There was a significant correlation between the large defect size (≥200 cm) and partial/total flap failure (n = 80, P = 0.023). There was also a significant correlation between large soft tissue defect size and any complication that is, total or partial failure and early or delayed unplanned return to the operating room (n = 80, P = 0.002). Of the flaps used, multivariate analysis revealed that latissimus flaps had higher odds for failure.

CONCLUSIONS

Soft-tissue defect size ≥200 cm can be associated with a higher rate of total or partial flap failure and any complication in acute trauma setting, which may be due to a larger zone of injury, a higher level of difficulty in achieving complete debridement, and a more complex microvascular dissection. Current and future efforts will need to continue to focus on risk stratification for limb salvage efforts because an accurate assessment of risk is important to the patient, health care provider, and the health care system in general.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Mechanical venous anastomosis in head and neck microvascular reconstruction as an equivalent to the gold standard

To define the most successful and efficient manner to perform venous microvascular anastomoses, the effectiveness of mechanical venous anastomosis in head and neck microvascular reconstruction is reviewed. Head and neck reconstruction with free flap techniques has become the norm and gold standard for large defects. This retrospective, multicenter case series of a single microvascular surgeon's experience with mechanical venous anastomoses specifically assessed the effectiveness of head and neck reconstruction and the complications associated with it. Data were collected from two separate academic centers and are reported from a consecutive series of patients over the course of 10 years. All patients underwent microvascular reconstruction of the head and neck region using venous couplers and flap survival. Flap survival was greater than 98% using mechanical venous couplers as the primary means for venous outflow in this series of 402 consecutive patients and 431 total microvascular flaps. Venous couplers were performed in every instance. The study shows that mechanical venous anastomosis provides a highly effective and efficient means for venous outflow in head and neck microvascular reconstruction, and should be considered equivalent to the gold standard suture technique, even in the most difficult cases.

A Comprehensive Approach to Lower Extremity Free-tissue Transfer

Background:

The purpose of this study was to introduce a comprehensive approach to lower extremity free-tissue transfer and report the clinical outcome that has been achieved with this approach.

Methods:

The comprehensive approach developed by the author includes patient selection, flap selection, selection of the recipient vessels, flap dissection, flap preparation, microvascular anastomosis, flap inset, immediate postoperative care, intermediate postoperative care, and further follow-up care. Each part of this approach has its own special considerations. In an 8-year period, 28 consecutive lower extremity free-tissue transfers were performed in 28 patients by the author. The clinical outcomes were recorded based on the success of free-tissue transfer, any reoperations related to the revision of microvascular anastomosis, and any partial or total flap loss during an 8-year follow-up.

Results:

All 28 lower extremity free-tissue transfers were performed successfully. All patients were discharged home once they tolerated dangling. No reoperations were needed for revision of microvascular anastomosis. No total or partial flap loss was encountered. Overall success of free-tissue transfer to the lower extremity in this series was 100%.

Conclusions:

An ideal outcome of free-tissue transfer to the lower extremity can be accomplished with this comprehensive approach developed by the author. With good surgical judgment, adequate microsurgical skill, step-by-step intraoperative execution, and a protocol-driven clinical practice, the reconstructive surgeon should be able to improve his or her success for free-tissue transfer to the lower extremity.

Free versus perforator-pedicled propeller flaps in lower extremity reconstruction: What is the safest coverage? A meta-analysis

INTRODUCTION

Currently, increasingly reconstructive surgeon consider the failure rates of perforator propeller flaps especially in the distal third of the lower leg are too important and prefer to return to the use of free flap at first line option with failure rates frequently lower than 5%. So, we performed a systematic review with meta-analysis comparing free flaps (perforator-based or not) and pedicled-propeller flaps to respond to the question "what is the safest coverage for distal third of the lower limb?"

METHODS

This review was conducted according to PRISMA criteria. From 1991 to 2015, MEDLINE®, Pubmed central, Embase and Cochrane Library were searched. The pooled estimations were performed by meta-analysis. The homogeneity Q statistic and the I² index were computed.

RESULTS

We included 36 articles for free flaps (1,226 flaps) and 19 articles for pedicled-propeller flaps (302 flaps). The overall failure rate was 3.9% [95%CI:2.6-5.3] for free flaps and 2.77% [95%CI:0.0-5.6] for pedicled-propeller flaps (P = 0.36). The complication rates were 19.0% for free flaps and 21.4% for pedicled-propeller flaps (P = 0.37). In more detail, we noted for free flaps versus pedicled-propeller flaps: partial necrosis (2.70 vs. 6.88%, P = 0.001%), wound dehiscence (2.38 vs. 0.26%, P = 0.018), infection (4.45 vs. 1.22%, P = 0.009). The coverage failure rate was 5.24% [95%CI:3.68-6.81] versus 2.99% [95%CI:0.38-5.60] without significant difference (P = 0.016).

CONCLUSION

In the lower limb the complications are not rare and many teams consider the free flaps to be safer. In this meta-analysis we provide evidence that failure and overall complications rate of perforator propeller flaps are comparable with free flaps. Although, partial necrosis is significantly higher for pedicled-propeller flaps than free flaps, in reality the success of coverage appears similar. © 2016 Wiley Periodicals, Inc. Microsurgery, 38:109-119, 2018.

Use of an Anastomotic Coupling Device for the Creation of Spliced Autogenous Grafts in Lower Extremity Revascularization

INTRODUCTION

Despite a recent rise in popularity of endovascular techniques, open bypass surgery is still required for treating many lower extremity vascular lesions. Greater saphenous vein (GSV) of adequate length and caliber for successful infrainguinal lower extremity bypass is unavailable in 15% to 45% of patients. To overcome limitations imposed by absent vein due to prior use, short vessel length, or sclerotic segments, both alternate (ie, basilic and cephalic) and GSV conduits may be "spliced" together in series via venovenostomy. Although vascular surgeons typically perform a hand-sewn venovenostomy, device-based venous coupling has been performed by plastic surgeons for many years. We therefore sought to review our experience with venous coupling for segmental lower extremity bypass graft assembly.

METHODS

A retrospective review was performed in all patients who underwent lower extremity revascularization using autogenous vein grafts spliced together with the Synovis (Birmingham, Alabama) anastomotic coupler at a single institution over a 5-year period.

RESULTS

The anastomotic coupler device was used on 5 patients for 7 venovenostomies. The mean age of patients was 66 years, and the mean follow-up period was 751 days. Two patients were lost to follow-up, while 2 other patients died of causes unrelated to their lower extremity bypass. The average time to perform venovenostomy was 3 minutes. Three patients developed stenosis of their composite graft at a site other than the venovenostomy, who were successfully treated with either angioplasty or bypass revision. One-year primary and primary-assisted patency rates were 50% and 75%, respectively.

CONCLUSIONS

Given the known benefits of the anastomotic coupling device when used for venous anastomoses in microsurgical reconstruction, transition of this device to the vascular surgery realm represents a logical progression. Although small, our series demonstrates that the anastomotic coupler can successfully be used for the formation of spliced autogenous grafts for lower extremity revascularization in the absence of adequate GSV.

Viability of anastomoses with coupler in extra-intracranial bypass: cadaveric study

BACKGROUND

The time required to perform an anastomosis in extra-intracranial bypass is approximately 20 to 60 minutes. The search for alternative methods to reduce the ischemic time remains vital.

OBJECTIVE

To evaluate Coupler anastomosis for extra-intracranial bypass in cadavers.

METHODS

In 8 fresh adult cadavers, the saphenous vein and radial artery were used as donor vessels. The superficial temporal and the extracranial internal and external carotid arteries were dissected. A wide craniotomy with a sylvian fissure opening was performed, exposing the middle cerebral and supraclinoid internal carotid arteries. The Coupler devices were tested in all 8 cadavers. The diameter of the donor and recipient vessels as well as the time required to perform the anastomosis were measured. Bypass permeability was evaluated by injecting saline solution under pressure, checking for leaks.

RESULTS

The anastomoses were successfully performed in all specimens. The size of the head of the fitting Coupler required the performance of a wide craniotomy (6 × 6 cm) and a wide opening of the sylvian fissure. The time required to perform each anastomosis ranged from 4 to 7 minutes, being easier with the radial artery than with the saphenous vein.

CONCLUSION

Coupler devices are helpful to perform the anastomoses, because they significantly reduce ischemia time. Their use is easier at the M1 segment, just before the bifurcation and after takeoff of the lenticulostriate arteries, and in the M2 segment. It would be advisable to have a smaller coupling system, allowing maneuverability in the deeper areas where space is limited.

Vein grafting your way out of trouble: Examining the utility and efficacy of vein grafts in microsurgery

INTRODUCTION

There is limited data on the indications, outcomes, and associated complications with use of interpositional vein grafts (IVG) in microsurgery. This study sought to critically examine and update the utility of this microsurgical technique.

METHODS

All microsurgical cases at a single institution from 2005 to 2011 were examined for use of IVGs in the primary procedure or during take back or salvage attempts. We examined the cohort overall and performed a subgroup analysis by timing of initial IVG.

RESULTS

In the study period, 1718 patients underwent 2368 free flaps. 51 IVGs were utilized in 38 patients (2.2%) and 38 flaps (1.6%). Eight (42.1%) of the primary procedure IVGs (n = 19) were planned preoperatively. Nine total flap losses (24%) occurred when IVGs were utilized, 89% of which occurred in the take back cohort (p = 0.02). However, planned IVG had a 100% success rate, and IVG utilized in the primary procedure overall had a 95% success rate. Importantly, A significantly higher rate of thrombotic events was noted in all primary cases where IVGs were utilized (p = 0.005).

CONCLUSIONS

This study demonstrates that IVGs can be utilized in primary free flap reconstructions with success rates exceeding 95%. However, in salvage procedures, the use of vein grafts does not approach the same rate of success likely due to multiple factors. Yet when utilized appropriately with thrombectomy and resection of the thrombosed vessel to healthy intima, IVGs can provide an important tool for flap salvage.

LEVEL OF EVIDENCE

prognostic/risk category, level II.