Use of a venous flap from an amputated part for salvage of an upper extremity injury

Systematic Review and Meta-Analysis of Unconventional Perfusion Flaps in Clinical Practice

BACKGROUND

Although unconventional perfusion flaps have been in clinical use since 1975, many surgeons are still deterred from using them, because of some reports of high necrosis rates.

METHODS

The authors performed a systematic review and meta-analysis of all articles written in English, French, German, Spanish, and Portuguese on the clinical use of unconventional perfusion flaps and indexed to PubMed from 1975 until July 15, 2015.

RESULTS

A total of 134 studies and 1445 patients were analyzed. The estimated survival rate of unconventional perfusion flaps was 89.5 percent (95 percent CI, 87.3 to 91.3 percent; p < 0.001). Ninety-two percent of unconventional perfusion flaps (95 percent CI, 89.9 to 93.7 percent; p < 0.001) presented complete or nearly complete survival. Most defects mandating unconventional perfusion flap reconstruction were caused by trauma (63.6 percent), especially of the hand and fingers (75.1 percent). The main complication of all types of flaps was a variable degree of necrosis (7.5 percent of all unconventional perfusion flaps presented marginal necrosis; 9.2 percent and 5.5 percent had significant and complete necrosis, respectively). There was a positive correlation between the rate of postoperative infection and the need for a new flap (Pearson coefficient, 0.405; p = 0.001). Flaps used to reconstruct the upper limb showed better survival than those transferred to the head and neck or to the lower limb (p < 0.001).

CONCLUSION

Unconventional perfusion flaps show high survival rates and should probably be used more liberally, particularly in the realm of upper limb reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

The free fillet flap after traumatic amputation: a review of literature and case report

Severe, mutilating hand injuries present difficult reconstructive scenarios. Often in these cases, portions of the amputated tissue may be used for reconstruction of the remaining digits and hand using the spare parts principle. The free fillet flap follows the spare parts concept. A literature review of free fillet flaps for hand and forearm coverage is provided. We also present a case report of a multi-digit and dorsal hand free fillet flap for coverage of a traumatic metacarpal hand. This flap demonstrates the value of ingenuity in planning during emergent trauma reconstruction.

The effect of hemodynamic remodeling on the survival of arterialized venous flaps

Objective

To evaluate the effect of hemodynamic remodeling on the survival status of the arterialized venous flaps (AVFs) and investigate the mechanism of this procedure.

Materials and Methods

Two 7 x 9 cm skin flaps in each rabbit (n=36) were designed symmetrically in the abdomen. The thoracoepigastric pedicle and one femoral artery were used as vascular sources. Four groups were included: Composite skin grafts group and arterial perfusion group were designed in one rabbit; AVF group and hemodynamic remodeling group by ligation of the thoracoepigastric vein in the middle were outlined in another rabbit. Flap viability, status of vascular perfusion and microvasculature, levels of epidermal metabolite and water content in each group were assessed.

Results

Highly congested veins and simple trunk veins were found using angiography in the AVF group; while a fairly uniform staining and plenty of small vessels were observed in the hemodynamic remodeling group. The metabolite levels of the remodeling group are comparable with those in the arterial perfusion group. There was no statistically significant difference in the percentage of flap survival between the arterial perfusion group and hemodynamic remodeling group; however, significant difference was seen between the AVF group and the hemodynamic remodeling group.

Conclusions

Under the integrated perfusion mode, the AVFs are in an over-perfusion and non-physiological hemodynamic state, resulting in unreliability and unpredictability in flap survival; under the separated perfusion mode produced by remodeling, a physiological-like circulation will be created and therefore, better flap survival can be expected.

Revascularization of Arterialized Venous Flaps through a Total Retrograde Reverse Blood Flow: Randomized Experimental Trial of Viability

Background:

Arterialized venous flaps (AVFs) have been used for reconstruction of soft tissue defects throughout the body. Several different revascularization models have been performed, but venous drainage through the arterial system has not been studied. In our total retrograde reverse blood flow (TRRBF) perfusion model, the arterial blood flow enters through the venous system and venous drainage exits through the arterial system.

Methods:

We developed a novel experimental model in rabbit ears to evaluate the capacity of TRRBF perfusion pattern to allow AVF viability. The ears were assigned to 3 groups: group 1, total devascularization without revascularization (n = 3); group 2, TRRBF (n = 12); and group 3, conventional AVF (n = 12). The ears were observed during a 30-day follow-up period, and clinical serial assessment of edema, cyanosis, and necrosis was performed. Tissue oxygenation was determined at the beginning and end of the follow-up. Histological analysis was performed.

Results:

Necrosis was found in 3/3 (100%) ears in group 1, 3/12 (25%) in group 2, and 0/12 (0%) in group 3 (95% CI, 0.505–0.994; P = 0.0001). In group 2, edema was higher (5/12, 41.66%) than in group 3 (0/12, 0%) (95% CI, 0.0135–0.65; P = 0.041). Cyanosis and venous congestion was of greater intensity and duration in group 2 than in group 3 (10.33 ± 4.51 vs 4.5 ± 2.06 d).

Conclusions:

Although evolution is torpid and prolonged in ears with TRRBF, 9/12 (75%) survived, suggesting that TRRBF can be used as a rescue method.

Clinical applications of venous flaps in the reconstruction of hands and fingers

In recent years, the venous flap has been highly regarded in microsurgical and reconstructive surgeries, especially in the reconstruction of hand and digit injuries. It is easily designed and harvested with good quality. It is thin and pliable, without the need of sacrificing a major artery at the donor site, and has no limitation on the donor site. It can be transferred not only as a pure skin flap, but also as a composite flap including tendons and nerves as well as vein grafts. All these advantages make it an optimal candidate for hand and digit reconstruction when conventional flaps are limited or unavailable. In this article, we review its classifications and the selection of donor sites, update its clinical applications, and summarize its indications for all types of venous flaps in hand and digit reconstruction.

Vein grafting in fingertip replantations

In this retrospective study, the survival rates of fingertip replantation with and without vein grafting were evaluated along with their postoperative functional and cosmetic results. One hundred twenty-one-fingertip amputations were performed in 103 patients between September 2002 and July 2007. Thirty-four amputated fingertips were replanted without vein grafting, while 87 amputated fingertips were replanted with vein grafting for arterial and/or venous repairs. The overall survival rates of the replantations with and without vein grafting were 90% (78/87) and 85% (29/34), respectively. The survival rates were 88% (36/41) with venous repair, 93% (25/27) with arterial repair, and 89% (17/19) with both. Nineteen patients without vein grafting and 48 patients with vein grafting had a follow-up period of more than one year. Good cosmetic and functional outcomes were observed in both groups of patients. The results show that vein grafting is a reliable technique in fingertip replantations, showing no significant difference (P > 0.05) in survival between those with and without vein grafting. Furthermore, no significant difference (P > 0.05) in survival was found between cases with vein grafts for arterial and/or venous repairs. In fingertip replantations with vein grafting, favorable functional and esthetic results can be achieved without sacrificing replantation survival.

Optimizing the arterialized venous flap

BACKGROUND

Outcome of arterialized venous flaps is quite varied. The authors' initial experiments showed that a good vascular bed contributes significantly to survival of the flap. In continuation of these experiments, this study aimed to understand the influence of architectural variations on flap outcome.

METHODS

Fasciocutaneous flaps were designed on the ears of New Zealand rabbits, and the animals were randomized into four groups having flaps that used the larger anterior marginal vein (1.3 mm) or the smaller central vein (0.6 mm) for arterial inflow, with or without isolation of the flap from its bed with a silicone sheet. Flaps were observed for area of flap survival and vasculature was assessed by microangiography.

RESULTS

Using the smaller central vein for arterial inflow (n = 15), arterialized venous flaps had an excellent outcome, with good flap survival in 100 percent of the animals (survival of >85 percent of flap area), and a mean flap survival area of 99.4 +/- 1.6 percent. Even when neovascularization was prevented by isolation of the flaps (n = 14), 92 percent of central vein flaps showed good survival, with a mean flap survival area of 93.3 +/- 7.3 percent, which was significantly better than that of anterior marginal vein flaps (n = 22), which showed good flap survival in only 27 percent of the animals (mean flap survival area, 76.4 +/- 12.1 percent).

CONCLUSIONS

Survival of arterialized venous flaps is optimized by using smaller-caliber veins for inflow and reserving larger-caliber veins for outflow. This regulates inflow and avoids high blood pressure, and arterialized venous flaps behave as physiologic flaps do, by not relying on neovascularization for survival.

Replantation of amputated finger composite tissues with microvascular anastomosis

Replantation of the partial amputated finger or the composite tissue in finger would achieve better functional and esthetic results than any reconstructive procedure. In this article, we report the results of microsurgical partial finger or composite tissue replantation at different anatomic sites of 24 fingers in 21 patients. Microvascular anastomosis was performed in all cases of replantation. For the digital palmar and lateral composite tissue defects, the proper palmar digital artery and volar or dorsal subcutaneous veins were repaired by end-to-end anastomoses. For the digital dorsal defects, the blood supply was reestablished by arterialization of a dorsal central vein in the replanted part with one of the proper palmar digital arteries. The average follow-up period was 12.3 months. Twenty-two of 24 fingers survived completely with good functional and esthetic results. Two replantations failed because of vascular complications. In conclusion, if the vascular vessels in amputations of partial finger and composite tissue of finger are suitable for anastomosis, a successful replantation of these parts with excellent functional and esthetic recovery can be achieved.

Upper Extremity Salvage With a Flow-Through Free Flap

In complex extremity injuries, which include composite tissue lost with devascularization caused by segmental vascular damage, simultaneous coverage of the defects with revascularizations should be required. One-stage reconstruction of both soft tissue coverage and vascular damage can be performed by a flow-through-type free flap. In this series, 5 patients between 13 and 36 years of age with wide composite tissue defects in the cubital region and segmental defects in brachial arteries were operated at our clinic between 1996 and 2003. With the aim of reconstructing the wide tissue defects in the cubital region as well as that of the brachial artery, a radial arterial flow-through flap was applied. The radial artery of the flow-through flap was anastomosed to the proximal ends of the brachial and ulnar arteries in an end-to-end fashion. In 4 of the patients, the radial arterial flow-through flap was prepared from the distal aspect of the wounded forearm and in 1 patient from the contralateral forearm. In the postoperative period, no complications related to the anastomosis were encountered in the flap with all anastomoses found to be patent, and distal circulation was restored. The radial arterial flow-through flap is very useful in the clinical field of major trauma of the cubital region with brachial artery damage with numerous advantages that include the opportunity to work in one single surgical area, shorter dissection times resulting from simple and fixed anatomy, perfect color and tissue adaptation, and the suitability of the vessel caliber and length.

Nonarterialized venous replantation of part of amputated thumb-a case report and review of the literature

Since the first successful replantation of a human thumb reported by Komatsu and Tamai in 1968, thousands of severed digits and body parts have been successfully salvaged. Restoration of anatomic form and function are the goals of replantation after traumatic tissue amputation. Regardless of anatomic location, methods include microsurgical replantation and nonmicrosurgical replantation, such as composite graft techniques. Numerous techniques to maximize tissue survival after revascularization have been described, including "pocket procedures" to salvage composite grafts, interposition vein grafts, and medicinal leeches to name a few. Artery-to-venous anastomoses have been performed with successful "arterialization" of the distal venous system in fingertip replantation. Although there is documented survival of free venous cutaneous flaps, to our knowledge this is the first report of a replanted composite body part (bone, tendon, soft tissues, and skin) utilizing exclusively multiple, microvascular, nonarterialized venous-venous anastomoses. We present a patient with an isolated band saw fillet amputation to the back of the thumb at the metacarpal-phalangeal joint region, resulting in a composite graft composed of bone, tendon, soft tissue, and skin. The hand wound provided no viable regional arterial inflow source, but there were multiple good caliber superficial veins present. The amputated tissues were replanted and revascularized by using only venous blood flow. The replanted part survival was 100% with excellent function of the digit. We conclude that a hand composite body part involving bone, tendon, soft tissues, and skin can survive replantation with a strict venous blood supply if sufficient good caliber, microvascular, venous-venous anastomoses are performed, granted that arterial inflow options are not available. This is an isolated case, yet introduces a new way of thinking regarding tissue replantation.