Vascular complication in free tissue transfer to the leg

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.

Ankle Skin Defects with Vascular Ehlers-Danlos Syndromes Treated by Posterior Tibial Artery Perforator Flap: A Case Report

CASE

A 46-year-old man with vascular Ehlers-Danlos syndrome (EDS) had an open ankle fracture with a 10 × 5-cm skin defect on the medial side of the ankle. The patient underwent open reduction and internal fixation, as well as coverage of the skin defect with a posterior tibial artery perforator flap, which led to successful outcomes.

CONCLUSION

We present the successful implementation of a posterior tibial artery perforator flap for the reconstruction of skin defects in a patient with vascular EDS. Despite the fragility of soft tissues, favorable surgical outcomes were observed.

The Great Saphenous Vein-An Underrated Recipient Vein in Free Flap Plasty for Lower Extremity Reconstruction: A Retrospective Monocenter Study

Background  Reconstruction of large soft tissue defects of the lower extremity often requires the use of free flaps. The main limiting factor and potential for complications lie in the selection of proper donor and recipient vessels for microvascular anastomosis. While the superficial veins of the lower leg are easier to dissect, they are thought to be more vulnerable to trauma and lead to a higher complication rate when using them instead of the deep accompanying veins as recipient vessels. No clear evidence exists that proves this concept.

Methods  We retrospectively studied the outcomes of 97 patients who underwent free flap plasty to reconstruct predominantly traumatic defects of the lower extremity at our institute. The most used flap was the gracilis muscle flap. We divided the population into three groups based on the recipient veins that were used for microvascular anastomosis and compared their outcomes. The primary outcome was the major complication rate.

Results  Overall flap survivability was 93.81%. The complication rates were not higher when using the great saphenous vein as a recipient vessel when comparing to utilizing the deep concomitant veins alone or the great saphenous vein in combination to the concomitant veins.

Conclusions  In free flap surgery of the lower extremity, the selection of the recipient veins should not be restricted to the deep accompanying veins of the main vessels. The superficial veins, especially the great saphenous vein, offer an underrated option when performing free flap reconstruction.

Overcoming severe calcified lower extremity artery in lower limb salvage operation by using the Fogarty catheter and vein graft

BACKGROUND

With severe vascular calcifications, vascular clamp application and utilizing the vessel for free flap recipient vessel becomes impossible. These obstacles can be overcome with the Fogarty catheter and vein graft.

PATIENTS AND METHODS

When unclampable artery was encountered intraoperatively, a vein graft was used to make a clampable recipient site for six diabetic foot patients (ages from 42 to 80). The end of the Fogarty catheter was inserted into the proximal end of the vein graft and the transected calcified vessel in sequence, and the balloon of the catheter was used as an intraluminal tourniquet. The remaining end of the vein graft was connected to the distal vessel with a vascular clamp.

RESULTS

Five short vein graft revascularization for segmental arterial occlusion, one long vein graft for recipient artery elongation was done (lengths from 2 to 13.8 cm). Three delayed, and two immediate anterolateral thigh flaps (sizes from 15 to 150 cm² ) were performed, and one patient received vein graft revascularization surgery only. Postoperative vascular sonography of all six patients showed well-maintained patency. Minor flap marginal disruption occurred at two patients but healed with conservative care. Postoperative follow-up was done for 1-18 months (average 7.17). Limb salvage was achieved for five patients and all five free flaps survived. However, for one patient, arterial restenosis at popliteal artery a month later lead to major amputation.

CONCLUSION

Using a Fogarty catheter and a vein graft may obtain perfect hemostasis during micro-anastomosis and achieve successful microvascular reconstruction in patients with severely calcified vessels.

Use of the superficial circumflex iliac artery perforator flap for reconstruction after sarcoma resection

BACKGROUND

Postoperative complications after flap-coverage in sarcoma treatment can postpone postoperative adjunct treatments. Here, we present our experience with the use of the superficial circumflex iliac artery perforator (SCIP) flap after sarcoma resection.

PATIENTS AND METHODS

Patients undergoing immediate reconstruction surgery with a flap after sarcoma resection at a single institution from February 2017 to April 2020 were identified. Patient demographics, tumor characteristics, surgical characteristics, and complications were examined.

RESULTS

Thirty-five consecutive patients underwent reconstructions using a SCIP flap (34 free and one pedicled SCIP flaps). We also identified 47 consecutive patients who underwent reconstruction with other pedicled or free flaps over the same time period. No significant differences were found in patient age, gender, defect size, or operative time between these two groups. The incidences of overall complications (20/47 [42.6%] vs. 3/35 [8.5%], p < .001), flap dehiscence (7/47 [14.8%] vs. 0/35 [0%], p = .018), and total flap complications (15/47 [31.9%] vs. 2/35 [5.7%], p = .005) were statistically greater in the control group than in the SCIP group.

CONCLUSION

With its minimal postoperative complication rate both in the reconstruction site and the donor site, the SCIP flap can be considered an optimal reconstruction option after sarcoma resection.

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.

Relationships of comorbidities and old age with postoperative complications of head and neck free flaps: A review

The aim of this study was to determine the relationships between free flap complications and old age or comorbidities. In a PubMed and Scopus search, the search terms (1) free flap OR microvascular anastomosis AND (2) elderly OR old age AND (3) complications OR comorbidity OR co-morbidity were used. Among the 62 full-text articles from 241 abstracts, 31 papers without sufficient content were excluded and 10 mined papers were added. Subsequently, 41 papers were reviewed. Overall complication rates of free flap increased significantly with age (p < 0.001; y = 0.457x + 13.464; 40.9% at 60 years, 45.5% at 70 years, and 50.0% at 80 years). Flap survival rates increased significantly (p < 0.001; y = 0.025x + 93.876). Donor site complication rates also increased significantly with age (p < 0.001; y = 1.238x - 63.700; 10.9% at 60 years, 23.0% at 70 years, and 35.3% at 80 years). The Kaplan-Feinstein index (KFI, OR = 7.944, 9.563), the Adult Comorbidity Evaluation-27 (ACE-27, OR = 5.854), the American Society of Anesthesiologists score (ASA, OR = 4.397), and the Index of Coexistent Diseases score (ICED, OR = 3.584) had statistically significant impacts on flap survival (p < 0.05). Diabetes (OR = 4.562) and chronic obstructive pulmonary disease (OR = 2.300) had statistically significant negative impacts on the flap survival rate (p < 0.05). Elderly patients had significantly higher Charlson Comorbidity Index (CCI) and ASA scores (p < 0.001). Similarly, elderly patients exhibited a significantly higher prevalence of dementia (p < 0.001) and use of aspirin at the time of surgery (p < 0.001). On the basis of these results, we suggest that the incidence of complications is directly related to the preoperative medical condition of an individual patient rather than to age.

Selection of the recipient vein in microvascular flap reconstruction of the lower extremity: analysis of 362 free-tissue transfers

Venous insufficiency is the most common cause of re-exploration in free-tissue transfers to the lower extremity. There is currently no consensus regarding the best approach to recipient vein selection. This study was designed to evaluate whether the type of venous system or the number of recipient veins would impact flap outcomes after microsurgical lower-extremity reconstruction. A retrospective study was conducted in 362 free-tissue transfers for lower-extremity reconstruction between 2003 and 2008. Flap outcomes were evaluated according to the selection of recipient vein system and number of veins. The deep venous system (80.4%) was more frequently selected than the superficial venous system (12.1%) or the combination of both systems (7.5%). In addition, one vein (65.5%) was more commonly used for anastomosis than two veins (34.5%). A total of 26 flaps (7.2%) presented with postoperative venous insufficiency. Male patients, composite defects including bones and the use of bone flaps presented higher rates of venous insufficiency with statistical significance. However, no significant differences were found among the different groups related to the age of patients, co-morbidities, aetiology, location of the defects or timing of reconstruction after trauma. The superficial venous system group was associated with a higher rate of venous insufficiency and partial flap loss compared with the deep venous system group (p = 0.036 and 0.018, respectively). One-vein-anastomosis flaps were associated with statistically significant fewer complete flap failure in comparison with two-vein-anastomosis flaps (p = 0.014). In conclusion, the assessment of recipient vein parameters by surgeon's experience is the best predictor of flap outcome in lower-extremity reconstruction. In our cohort of patients, the deep venous system was more reliable than the superficial venous system, but the use of more than one vein for anastomosis did not correlate with better flap outcomes.

Outcome of simultaneous and staged microvascular free tissue transfer connected to arteriovenous loops in areas lacking recipient vessels

BACKGROUND

Arteriovenous loops are an indispensable tool in free flap surgery when appropriate recipient vessels are missing. In this study, the authors analyzed whether the outcome differs when flaps were transferred simultaneously or subsequently after construction of arteriovenous loops.

METHODS

Twenty-seven patients requiring free tissue transfer received arteriovenous loops by pedicled or free vein grafts because of inadequate local recipient vessels. In head and neck reconstruction, pedicled brachiocephalic or free saphenous vein grafts were anastomosed to cervical or axillary vessels. Pedicled major saphenous vein grafts were used in the pelvic area whereas, in lower leg and foot reconstruction, free saphenous or brachiocephalic veins were used. Flaps were transferred simultaneously (n = 10) or 4 to 17 days later (n = 17).

RESULTS

Thrombosis required revision in staged transfer (n = 3 patients) or in simultaneous flap transfer (n = 2). No free flap was lost. Fisher's exact test did not indicate a significant difference between a simultaneous or staged flap transfer.

CONCLUSIONS

Temporary arteriovenous loops provide adequate recipient vessels and flow to supply microvascular free flap tissue transfer in areas lacking recipient vessels and in which no other reconstructive options exists. No statistical differences in complications and overall outcome were found between immediate or secondary free tissue transfer. Meticulous monitoring of microvascular perfusion, however, is mandatory in both approaches and early intervention is necessary to ensure successful tissue transfer.

Free Tissue Transfer to the Lower Extremity Distal to the Zone of Injury: Indications and Outcomes over a 25-Year Experience

BACKGROUND

Microvascular free flap anastomoses performed for lower extremity reconstruction are traditionally proximal to the zone of injury. The authors assessed the feasibility and outcomes of microvascular free flaps with anastomoses performed distal to the zone of injury.

METHODS

The authors retrospectively reviewed all microvascular free flaps performed at their institution over the past 10 years for lower extremity reconstruction and compared this group with their previously published experience (January of 1979 through August of 1995). Between September of 1995 and May of 2005, 119 flap procedures were performed for lower extremity reconstruction. Twenty-eight flaps (24 percent) were anastomosed distal to the zone of injury and 87 (76 percent) were anastomosed proximally. There were insufficient data on the location of the anastomosis for four free flaps (all successful).

RESULTS

Twenty-seven of 28 distal microvascular free flaps were successful (96 percent); two (7 percent) required emergent postoperative reexploration of the anastomosis. Of the 87 proximal flaps, 79 (91 percent) were successful and eight (9 percent) failed. There was no statistically significant difference in the success rate of microvascular free flaps between the proximal and distal anastomosis groups (p = 0.30, Fisher's exact test). Combined with the data from the authors' previous series (January of 1979 to August of 1995), there were 63 free flaps with anastomosis performed distal to the zone of injury; 61 (97 percent) were successful.

CONCLUSION

The authors' extensive 25-year experience with lower extremity reconstruction demonstrates that in appropriately selected patients, free tissue transfer to recipient vessels distal to the zone of injury is reliable and in certain cases preferable.

A simple classification for standardisation of nomenclature in free flap outcome

The numbers of free flap donor site as well as their indications are constantly increasing. Despite increasing popularity of microvascular reconstructive procedures, literature lacks clear and objective outcome criteria. This paper reports on a simple outcome classification that has become a routine part of the unit's large workload of microvascular outcome recording. The classification was formed through a retrospective analysis of 241 consecutive cases from 2000 to 2001 and is a five graded numerical classification. Grade 1 equates to total success without co-morbidity and grade 5 to a major complication such as amputation, etc., whatever the status of the flap itself. From 2002 to 2005 the classification was prospectively used on 527 consecutive cases with ease of integration into routine clinical practice. The Classification would enable a more objective record keeping thus analysis of the outcome. It would allow a more realistic comparison of different techniques or donor types as well set a benchmarking level for further improvement of the results.

Lower Extremity Trauma: Trends in the Management of Soft-Tissue Reconstruction of Open Tibia-Fibula Fractures

BACKGROUND

Open lower leg fractures with exposed bone or tendon continue to be challenging for plastic surgeons. Microvascular free-tissue transfer increases the ability to close wounds, transfer vascularized bone, and prevent amputation, yet remains a complex, invasive procedure with significant complication rates, donor-site morbidity, and failure rates. This review documents the changing treatment protocol in the authors' institution for these injuries.

METHODS

Two hundred ninety consecutive open tibia-fibula fractures over a 12-year period (1992 to 2003) were retrospectively reviewed and methods and outcomes were compared by grouping the fractures into 4-year intervals.

RESULTS

The number of open lower extremity fractures increased, whereas the distribution of Gustilo grade I to III fractures remained unchanged. Overall, free-tissue transfer was performed less frequently and constituted 20 percent of reconstructions in period 1 (1992 to 1995), 11 percent in period 2 (1996 to 1999), and 5 percent in period 3 (2000 to 2003). For the most severe fractures, Gustilo grade III, free-flap reconstruction has decreased significantly, constituting 42 percent, 26 percent, and 11 percent of procedures in periods 1, 2, and 3, respectively. Local flaps for grade III fractures have remained relatively constant throughout the study. In contrast, local wound care for grade III fractures, including skin grafts, delayed primary closures, and secondary intention closures has significantly increased from 22 percent to 49 percent of reconstructions from periods 1 through 3. In 1997, the authors began to use the vacuum-assisted closure device and now use it in nearly half of all open fractures. Despite this trend, there has been no change in infection, amputation, or malunion/nonunion rates and a decrease in reoperation rate with at least 1-year follow-up.

CONCLUSIONS

These results demonstrate a change in practice, with a trend down the reconstructive ladder, currently using fewer free flaps and more delayed closures and skin grafts with frequent use of the vacuum-assisted closure sponge. Possible reasons for this change are a better understanding of lower leg vascular anatomy and better use of improved wound care technology.

Microvascular anastomosis through the tibial tunnel: a new technique in free-tissue transfer to the leg

Free-tissue transfer to a severely traumatized leg has a high rate of vascular complications. We present three successful cases using a new technique of microvascular anastomosis through the tibial tunnel. Because of the unavailability of anterior tibial artery due to posttraumatic vascular disease, donor vascular pedicles were passed posterior to the tibia through the tibial tunnel and anastomosed to the posterior tibial artery or its branch in an end-to-end fashion. The flaps survived perfectly, without any vascular complication. This technique represents a safe route, and the shortest route, to an expected anastomosis point. Our technique is indicated especially in cases with a single-vessel leg.