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

In Search of Optimal Practice: A Retrospective Comparative Study of Single- Versus Dual-Venous Anastomosis in Microvascular Flaps

Background In the current era of reconstructive surgery, microvascular free flap transfers are the most popular reconstructive procedures performed. The main reason for the failure of the flap and re-exploration is venous thrombosis. Traditionally, most surgeons prefer performing two-vein anastomoses. There is insufficient literature to support that dual-venous anastomosis is better than single-venous anastomosis. In this study, we compared the success rate of single-venous anastomosis with dual-venous anastomosis of different free flap reconstructions. Methodology The retrospective cohort study was conducted with a total of 101 patients. Eighty-three were in the one-vein group, and the remaining 18 were in the two-vein group. Outcomes were compared between the two groups regarding re-exploration and flap failure. Results The overall success rate of free flap reconstruction was 96%. Among the 101 free flaps, 16 flaps had signs of venous compromise and were re-explored. Out of the 16 flaps, 11 flaps (13.2%) were in the one-vein group, and 5 flaps (27.7%) were in the two-vein group. In the two-vein group, 100% of the flaps were salvaged, and in the one-vein group, only 63% of the flaps were salvaged after re-exploration. There was no statistically significant difference between the one-vein group and the two-vein group concerning re-exploration.  Conclusions The rate of re-exploration was lower in the one-vein group when compared to the two-vein group. However, this difference was not statistically significant. Hence, a single-vein anastomosis is sufficient for a successful microvascular free flap. However, the rate of flap salvage is better with two-vein anastomosis if there is venous congestion.

One Versus Two Veins in Free Anterolateral Thigh Flap Reconstruction: A Systematic Review and Meta-Analysis

There is considerable debate in the literature as to whether one or two venous anastomoses are optimal in the anterolateral thigh (ALT) free-flap reconstruction. The literature is currently devoid of a systematic review and meta-analysis of studies evaluating these procedures. This review will therefore be the first to address this clinical question. In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, two authors (EW and SR) independently searched the following electronic databases: MEDLINE, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials (CENTRAL). Case-control, randomised control and observational studies were included. The authors did not include case reports, case series, letters or abstracts. All patients were included regardless of age, co-morbidity status, and the anatomical site of reconstruction. Venous congestion/thrombosis, flap take-back rate due to venous insufficiency, flap loss and operative time were the primary outcome measures. Secondary outcome measures included partial flap loss and haematoma formation. The Newcastle Ottawa Scale was used to assess the risk of bias in the included studies. Review Manager 5.4 data synthesis software was used for the analysis. The authors identified eight observational studies, with a total of 1741 patients reviewed, demonstrating a significantly lower flap take-back rate for a double venous anastomosis and a shorter operative time in the single venous anastomosis group. However, other reported measures, including venous congestion and flap loss, showed a non-significant difference (P>0.05). The limitations of the evidence included in this review were that all studies were observational in design. The flap take-back rate is significantly less when anastomosing two veins, and the authors recommend that utilising a second vein can circumvent the caveat of venous compromise.

Venous Size Discrepancy Is a Critical Factor When Using Superficial Temporal Vessels as Recipient Vessels for Free Flaps

BACKGROUND

 Superficial temporal vessels have been used successfully as recipient vessels for head and neck reconstruction. This study evaluates the impact of several treatment variables on flap failure and take-back rate when using these recipient vessels.

METHODS

 We conducted a retrospective study of all microsurgical reconstructions using superficial temporal vessels as recipient vessels in a period of 10 years. Variables collected included previous treatments (radiotherapy, chemotherapy, neck dissection, free flap reconstruction), type of flaps used (soft tissue, osteocutaneous), and vessel size discrepancy between donor and recipient vessels.

RESULTS

 A total of 132 patients were included in the study. The flap success rate was 98.5%. The take-back rate was 10.6%. The most frequent reason for take-back was venous congestion secondary to thrombosis. None of the studied variables was associated with flap failure. Reconstructions using osteocutaneous flaps and vein diameter discrepancy (ratio ≥ 2:1) had significantly higher take-back rates.

CONCLUSION

 Flaps with a significant size discrepancy between donor and recipient veins (ratio ≥ 2:1) and fibula flaps (compared with soft tissue flaps) were associated with a higher risk of take-back. It is crucial to minimize venous engorgement during flap harvest and anastomosis, and limit vein redundancy during flap in-setting.

Analysis of Selection of Recipient Vein, Number of Outflows, Style and Technique in Head and Neck Venous Anastomosis and a Proposed Algorithm

Surgeons have preferential ways of performing venous anastomosis in head and neck microsurgery. However, controversies exist regarding the superiority of each method. This study aims to determine the effects of these variables on the rates of thrombosis and flap failure, and propose an algorithm to be used as a facilitator in the decision-making process. A total of 208 microsurgical reconstructions on 199 patients from a single surgeon's data were evaluated. Selection of recipient vein (superficial vs. deep), style of anastomosis (end-to-end vs. end-to-side), number of outflows (one vs. two) and technique of anastomosis (hand-sewn vs. coupler) were compared. Selection was done according to the pre- and intraoperative plan, as well as, surgeon's clinical judgement. Outcomes were determined as rates of venous thrombosis and flap failure. Five patients (2.4%) had venous problems, leading to two partial and three total flap failures. Selection of the recipient vein, style and number of outflows did not affect the outcomes, whereas coupler use decreased the rates of venous thrombosis and flap failure (p=0.008). Although it is difficult to set dogmatic criteria to achieve consistent outcomes, coupler use in this study prevented flap failure. An algorithmic approach was proposed with the results of the data and literature to increase the success in microsurgical anastomosis. Surgeons should use algorithms and sound judgement with adherence to microsurgical principles to obtain the best results for each patient.

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.

[Defect coverage after severe soft tissue infections: when and how?]

Severe infections frequently cause large soft tissue defects which require early defect coverage by plastic surgeons. A number of reconstructive treatment options are available, ranging from local flaps to microvascular free flap reconstructions. In this respect it is important that the selection of the optimal reconstructive technique is made based on individual patient characteristics and in a timely manner. Weeks of inpatient treatment with vacuum dressings often delay defect coverage and should be avoided as they burden both the patient and the healthcare system. Therefore, it is in the best interest of patients to receive early treatment by plastic surgeons. This manuscript presents the essential reconstructive treatment approaches based on highly informative case reports of patients from the plastic surgical practice at a university hospital.

Comparison of Internal Jugular Vein System Anastomosis and External Jugular Vein System Anastomosis in Free Flaps for Head and Neck Reconstruction: A Meta-Analysis

PURPOSE

The purpose of the present study was to investigate the differences in postoperative thrombosis and flap failure between internal jugular vein (IJV) system anastomosis and external jugular vein (EJV) system anastomosis in free flaps for the reconstruction of head and neck defects.

MATERIALS AND METHODS

We searched PubMed, Web of Science, EMBASE, Chinese BioMedical Literature Database, and other databases until March 2019 for studies that had reported data for anastomosis for the 2 different venous systems in the microvascular free-flap reconstruction of head and neck defects. We assessed thrombosis and flap failure in patients undergoing anastomosis of the IJV system and patients undergoing anastomosis of the EJV system.

RESULTS

Nine studies with a total of 2051 patients with venous anastomosis were included in the present meta-analysis. IJV system anastomosis showed a significantly lower incidence of venous thrombosis than did the EJV system (relative risk [RR], 0.55; 95% confidence interval [CI], 0.37 to 0.82). Eight studies were included in the analysis of the flap failure rate, which showed a lower failure rate for the IJV system anastomosis than for the EJV system (RR, 0.59; 95% CI, 0.35 to 1.00).

CONCLUSIONS

The incidence of thrombosis and flap failure after venous anastomosis in the IJV system was lower than that in the EJV system. The results from the present study have shown that the IJV system should be the first choice for venous anastomosis in the reconstruction of free flaps.

One Versus 2 Venous Anastomoses in Free Flap Surgery: A Systematic Review and Meta-Analysis

Background

The necessity of a second venous anastomosis in free flap surgery is controversial. The purpose of this systematic review is to determine whether venous flap failure and reoperation rates are lower when 2 venous anastomoses are performed. The secondary objective is to determine whether venous flap failure and reoperation rates are lower when the 2 veins are from 2 different drainage systems.

Methods

A comprehensive search of the literature identified relevant studies. Investigators independently extracted data on rates of flap failure and reoperation secondary to venous congestion. A meta-analysis was performed; odds ratios (ORs) were pooled using a random-effects model and 95% confidence intervals (CIs).

Results

Of 18 190 studies identified, 15 were included for analysis. The mean sample size was 287 patients (minimum = 102, maximum = 564). No statistically significant difference in venous flap failure was found when comparing 1 versus 2 venous anastomoses (OR: 1.35; 95% CI: 0.46-3.93). A significant decrease in reoperation rate due to venous congestion was shown (OR: 3.03; 95% CI: 1.64-5.58). The results favor using 2 veins from 2 different systems over veins from the same system (OR: 0.16; 95% CI: 0.02-1.27).

Conclusions

There is low-quality evidence suggesting that the use of 2 venous anastomoses will lower the rate of reoperation due to venous congestion. There are insufficient data published to meaningfully compare outcomes of flaps with 2 venous anastomoses from different systems to flaps with anastomoses from the same system.

One versus two venous anastomoses in microvascular lower extremity reconstruction using gracilis muscle or anterolateral thigh flaps

INTRODUCTION

Free tissue transfers are a highly reliable procedure routinely performed for reconstruction of a wide range of defects. Main complication in free flap surgery is usually venous thrombosis. Many technical controversies exist regarding the technical details of the microvascular anastomosis in order to prevent occurrence of thrombosis and optimize outcomes. We therefore evaluated our results regarding the execution of one versus two venous anastomoses in a variety of free flaps (fasciocutaneous- or muscle free flap) utilized for lower limb reconstruction.

PATIENTS AND METHODS

Between 2009 and 2015, 354 patients underwent 386 free ALT- or gracilis flaps for lower limb defect reconstruction after trauma, infection, or malignancies at our institution. The data was retrospectively screened for patients' demographics, perioperative details, flap survival, and surgical complications. The cases were divided into two groups regarding the number of microsurgically performed venous anastomosis: one versus two veins.

RESULTS

Regarding the preoperative evaluation, there were no significant differences regarding comorbidities between the two groups. Overall, there was no significant difference regarding the rate of major (1 vein: 20.38% versus 2 veins: 18.78%, p>0.05) and minor (1 vein: 1.27% versus 2 veins: 2.18%, p>0.05) surgical complications during our 3-months follow-up period. Major complications included total flap losses of 5.73% (1 vein) versus 8.78% (2 veins).

CONCLUSION

This study analyzed a large series of microsurgical reconstructions, with a focus on the impact of the number of venous anastomosis. The findings suggest that successful free tissue transfer for lower limb reconstruction can be achieved independent of the number of venous anastomoses, however two should be performed when technically feasible.

Reconstruction of Postburn Contracture of the Forefoot Using the Anterolateral Thigh Flap

Background

Severe forefoot deformities, particularly those involving the dorsum of the foot, cause inconvenience in daily activities of living including moderate pain on the dorsal aspect of the contracted foot while walking and difficulty in wearing nonsupportive shoes due to toe contractures. This paper presents clinical results of reconstruction of severe forefoot deformity using the anterolateral thigh (ALT) free flap.

Methods

Severe forefoot deformities were reconstructed using ALT flaps in 7 patients (8 cases) between March 2012 and December 2015. The mean contracture duration was 28.6 years.

Results

All the flaps survived completely. The size of the flaps ranged from 8 cm × 5 cm to 19 cm × 8 cm. The mean follow-up period was 10 months (range, 7 to 15 months). There was no specific complication at both the recipient and donor sites. There was one case where the toe contracture could not be completely treated after surgery. All of the patients were able to wear shoes and walk without pain. Also, the patients were highly satisfied with cosmetic results.

Conclusions

The ALT flap may be considered ideal for the treatment of severe forefoot deformity.

Recipient vessel selection in the difficult neck: Outcomes of external carotid artery transposition and end-to-end microvascular anastomosis

BACKGROUND

Selection of recipient vessels for head and neck microvascular surgery may be limited in the previously dissected or irradiated neck. When distal branches of the external carotid artery (ECA) are unavailable, additional options for arterial inflow are needed. Here we propose high ligation of the ECA and transposition toward the lower neck as an alternative.

METHODS

After obtaining institutional approval, patients who underwent head and neck tumor resection and simultaneous free flap reconstruction were identified over a 5-year period. Patients whose recipient artery was listed in the operative report were included. Chart review was performed to identify patient demographics, operative details, and patient and flap complications. In cases where the ECA was used, the artery was traced distally with care taken to protect the hypoglossal nerve. The ECA was then divided and transposed toward the lower neck where an end-to-end microvascular anastomosis was performed.

RESULTS

The recipient artery used for head and neck microsurgery was available for 176 flaps, and the facial (n = 127, 72.2%) and external carotid (n = 19, 10.8%) arteries were most commonly used. There were 0 flap thromboses in the ECA group compared to 3 flap thromboses that occurred with other recipient arteries (P = 1.00). No cases of first bite syndrome or hypoglossal nerve injury were identified.

CONCLUSIONS

The ECA may be transposed toward the lower neck and used for end-to-end microvascular anastomosis without complication of hypoglossal nerve injury or first bite syndrome. This method may be considered an alternative in patients with limited recipient vessel options for head and neck microsurgery. © 2015 Wiley Periodicals, Inc. Microsurgery 37:96-100, 2017.