The effect of an implantable Doppler probe on the salvage of microvascular tissue transplants.

One hundred forty-seven flaps in 135 consecutive patients undergoing microvascular transplantation were monitored using a miniature Doppler ultrasonic probe. Using a modification of a technique described previously by Swartz, the probes were secured to the outflow vein of the flap with Vicryl mesh. Twenty instances of thrombosis or spasm were detected in 16 patients, and all flaps were salvaged (100 percent). There were four false positive and no false negative results. This probe allows for safe, continuous monitoring of flap blood flow, which permits the rapid detection and hence rapid treatment of postoperative complications. Our experience suggests that a significant improvement in the salvage rate of microvascular transplants may be attainable with the use of this device.

Using the Internet for rapid exchange of photographs and X-ray images to evaluate potential extremity replantation candidates.

OBJECTIVE: To implement a low-cost system of transmitting high-quality digital photographs of mutilating extremity injuries using the speed of the Internet. DESIGN: A high-resolution digital camera and simple hardware and software platform are used to take and transmit images via electronic mail. The images are received within minutes by the consultant, and an assessment can be made. RESULTS: A low-cost and high-quality system can easily be implemented. Images can be seen by consultants only a few minutes after they are obtained. The quality of the reproductions is excellent, and they are handled exactly as other photographs. CONCLUSION: This technique can be widely applicable and inexpensive to initiate in any emergency room. It allows rapid assessment of extremity injuries and x-ray images by expert consultants, who can then evaluate the replantation or revascularization potential of extremity trauma cases. This can eliminate unnecessary and often expensive transfer of patients who are not candidates for replantation.

A clinical study of end-to-end versus end-to-side techniques for microvascular anastomosis.

The choice of microvascular anastomotic technique, end-to-end versus end-to-side, is still an item of debate. A review of the literature reveals no difference in patency rates in animal models where there is no size discrepancy. The available clinical evidence stems from Godina's early experience, proclaiming a higher failure rate with end-to-end anastomoses. Factors such as size mismatch and use of injured vessels, rather than anastomotic technique, may have been responsible. This clinical study examines the fate of over 2000 microvascular anastomoses performed in more than 900 tissue transplants. Complications attributable to the anastomosis were considered failures of the anastomosis, were tabulated, and were compared between the two techniques. The end-to-end and end-to-side microvascular techniques were found to be equally effective when properly applied. The choice of technique therefore should be secondary to factors influencing the choice of recipient vessel, such as the condition of the vessel, its accessibility, and the preservation or augmentation of maximal distal flow to an extremity.

[202 toe transfers to the hand]. / 202 Zehentransplantate an die Hand.

This retrospective study analyzed 202 toe-to-hand transplants performed over the last 20 years at the Davies Medical Center, San Francisco (USA). The overall success rate was 97%. Toe transplants for finger reconstruction yielded optimal functional and cosmetic results due to their anatomical similarity to fingers. The great toe was preferably used for thumb reconstruction, whereas the other toes were used for reconstruction of the long fingers. Early reconstructions, multiple simultaneous toe transplants, and interventions combining toe transplantation with free flaps seemed to be advantageous because of shorter rehabilitation and comparable results.

Microvascular replantation of scalp and facial parts.

Replantation of fingers, hands, feet, and extremities has become a relatively common procedure. There are a number of reports of successful replants of facial parts. Since the feeding vessels are extremely small, these replants are most challenging. Venous outflow is the most common problem, and leeches and anticoagulants are commonly needed, resulting in considerable blood loss and transfusions. Nonetheless, the successful replantation of a facial part yields an aesthetic and functional result far superior to any other reconstructive option. We review our experience with 7 scalps, 4 ears, and 2 lips.

Salvage of wounds following failed tissue transplantation.

During the past 20 years, 972 microvascular transplantations have been performed for 783 patients, with an overall failure rate of 6.2 percent. Fifty-four of the 60 failed transplantations were available for long-term follow-up and were retrospectively reviewed with respect to the original indications for transplantation, the number, and the type of salvage procedures performed following transplant failure. This study illustrates that the choice of salvage procedures performed following transplant failure depends on the original indications, the location, and the severity of the resultant wound. Failure following transplantation for coverage of contour defects or unstable wounds can often be managed by non-microsurgical methods. In contrast, when the indications for transplantation included the transfer of specialized tissues for thumb or digit reconstruction, the restoration of motor or sensory function, or the coverage of a limb-threatening wound, requirements for reconstruction could be satisfied only by a second successful tissue transplant. Eighteen of the 54 cases underwent an additional transplantation, with an 89 percent success rate.

Unrecognized injuries in patients referred for emergency microsurgery.

Replantation of amputated parts and emergency microvascular repair of injured extremities are the two most common applications of clinical microsurgery. A major complication of emergency referral of such cases is the existence of the other injuries unrecognized at the time of initial evaluation. We have reviewed this complication within a series of emergency microsurgical cases referred to this unit. Several reports examining this problem of missed injuries exist in the general trauma literature. To our knowledge this study is the first to look at this important problem in the context of acutely injured patients referred for emergency microsurgery. A retrospective analysis of patients referred to Davies Medical Center over a 7-year period was performed. Nine of 1100 patients (0.8%) transferred to our unit for microsurgical evaluation and treatment had unrecognized coexisting injuries that put those patients at high risk for injury-specific morbidity and demanded immediate changes in the original care planned at the time of referral. Brief case histories of these patients are outlined. We review the trauma literature of such injuries. A concise protocol elucidating the guidelines and pitfalls of emergency microsurgical referral is offered.

Microvascular transplant of the gastrocnemius muscle in rats.

The rat gastrocnemius muscle can serve as a vascularized, innervated muscle transplant model. To establish the anatomic and technical details of this model, we performed ten gastrocnemius transplants and collected data on muscle weight, dimension, and vessel caliber from each muscle. The muscle, consisting of medial and lateral heads, is supplied by pairs of sural vessels averaging 0.2 mm in diameter. These vessels, however, can be taken in continuity with the femoral vessels (averaging 1.0-1.6 mm in diameter), which are used for transplantation. The muscles weighed an average of 2.8 g, and the average pedicle length was 24 mm. Eight of ten transplanted muscles were viable with intact circulation at 72 hr. The gastrocnemius transplant was technically reliable, and the muscle bulk and contour could allow biochemical and functional studies. Donor site morbidity limits this model to transplantation studies.

Hand reconstruction with partial toe and multiple toe transplants.

Microsurgical transplantation of toes to the hand can serve as an excellent method of reconstructing the severely traumatized hand. This article reviews the authors' experience with 188 great-toe and second-toe transplants. Detailed operative sequence and postoperative care are also discussed.

Treatment of chronic osteomyelitis of the lower extremities with debridement and microvascular muscle transfer.

Of our 55 patients treated for lower extremity osteomyelitis, 91% underwent debridement and microvascular muscle flap coverage with eradication of their infections and restoration of ambulation. This series of patients helps to solidly establish the efficacy of this approach to the treatment of osteomyelitis.

Improved salvage of complicated microvascular transplants monitored with quantitative fluorometry.

Quantitative fluorometry has been used to monitor circulation in transplanted toes and cutaneous flaps in our unit since 1982. Analysis of 177 uncomplicated transplants monitored by quantitative fluorometry shows that this technique has low false indication rates for arterial occlusion (0.6 percent of patients) and venous occlusion (6.2 percent of patients). None of these patients was reexplored because of a false monitor reading, and except for single abnormal sequences, monitoring appropriately indicated intact circulation throughout the postoperative period. Quantitative fluorometry has correctly indicated vascular complications in 21 (91.3 percent) of 23 transplants over an 8-year period. The salvage rate (85.7 percent) of the fluorescein-monitored reexplored transplants was significantly higher than the salvage rates of similar reexplored transplants not monitored with fluorescein and of reexplored muscle flaps (which cannot be monitored with the fluorometer used at this unit). These clinical data indicate that quantitative fluorometry is a valid and useful postoperative monitor for transplanted toes and cutaneous flaps.

Microvascular tissue transfer in paediatric patients: analysis of 106 cases.

We report a series of 106 microvascular transplants performed in paediatric patients between 1973 and 1989. Eighty-eight percent of these flaps were successful. Two of the 13 failed flaps (1.9%) in this series were lost because of small vessel size. Otherwise, success rates (93% in the last 5 years) and complications were comparable to our adult cases. No growth-related complications were noted either in recipient or donor sites. We conclude that microvascular transplantation is a reliable procedure in children.

Eleven consecutive combined latissimus dorsi and serratus anterior free muscle transplantations.

We reviewed our experience with 11 consecutive combined latissimus dorsi and serratus anterior free-muscle transplantations from 1980 to 1990. All 11 flaps were successful and there was minimal morbidity. This combined muscle flap is ideal for soft-tissue coverage in extensive lower extremity wounds, in mutilating hand injuries with dorsal and palmar defects, and in situations when a long vascular pedicle is needed to get out of the "zone of injury."

The contributions of microvascular surgery to emergency hand surgery.

Microvascular surgery has revolutionized the field of emergency hand surgery in the areas of replantation and microvascular transplantation. Amputated parts from as small as a distal phalanx to the entire extremity can now be successfully replanted and unreplanted, or missing parts can be restored and reconstructed with immediate microvascular transplants (MVTs). MVTs can be used to cover exposed vital structures and replace missing complex parts. Part or whole digits can be reconstructed, with up to 4 toe transplants. Joints, bones, and muscles can be replaced with osteocutaneous and neuromyovascular transplants. Using the same approach for multiple replants, teams of 4 to 6 surgeons operating simulatneously and sequentially around the clock can accomplish multiple microvascular transplants in the acute setting. The classical principle of hand surgery, "preserve length and function", can now be modified to "restore length and function."

Microvascular transfer of anterior and posterior gracilis muscles in rats.

A microvascular free muscle flap in rats using the anterior and posterior gracilis muscles with femoral vessels as its pedicle is presented. The gracilis muscles form a single unit supplied by the muscular branch artery and vein, averaging 0.3 mm and 0.4 mm in diameter, respectively. These small sizes preclude their use in transplantation. However, the muscular branch vessels in continuity with the femoral vessels can be used for the vascular pedicle in this muscle transplant. This muscle flap was transplanted to the contralateral femoral vessels by end-to-end anastomosis in 15 rats. Thirteen animals survived and 11 flaps were viable at 3 days for a success rate of 85%. The gracilis flaps averaged 674 mg in weight, 1.87 cm X 1.36 cm in size, and 7.23 mm in pedicle length. This free muscle flap model is reliable, relatively easy to perform, and provides adequate muscle bulk for pharmacologic and biochemical studies in transplanted muscle. No lower extremity complications were noted following femoral vessel ligations.