Clinical evaluation of laser Doppler blood flow measurements in free flaps

Adequate assessment of blood flow in free flaps with early detection of circulatory failure is an unresolved clinical problem. In 23 patients undergoing microvascular free tissue transfers, laser doppler blood flow measurements and clinical observations were made hourly for the first two postoperative days. There was 1 flap failure in 6 instances in which it was clinically necessary to intervene, by reexploration or draining a hematoma, to ensure the survival of the flap. It was hypothesized that the laser doppler measurements would predict future clinical events. However, it was found that although these measurements did correlate with clinical observations, they did not predict them and were actually less accurate in indicating the need for clinical intervention or the final outcome of the free flap procedure.     

Complications of free flap donor sites

A variety of free tissue transfers are available for microsurgical reconstruction. To date little attention has been placed on the donor site, both from the potential for acute complications as well as long-term morbidity. In this review the various types of tissue transfers in different anatomical locations have been assessed for potential problems at the donor site. An assessment system is proposed to better evaluate this problem as well as to allow comparison of the different donor sites. © 1995 Wiley-Liss, Inc.     

Complications and morbidity of the donor and recipient sites in 123 lateral arm flaps.

The lateral arm flap is a reliable and versatile free tissue transfer. However, the donor and recipient sites may produce an assortment of relatively minor complaints in a large proportion of patients. 109 (89%) out of 123 lateral arm flaps performed over a seven-year period were reviewed an average of three years after surgery. Unsatisfactory appearance of the donor site was noted by 27% of patients and was twice as likely to be reported by female patients and in cases in which the donor site was repaired by a split-thickness skin graft rather than by primary closure. Elbow pain was reported by 19%. Numbness in the forearm was reported by 59% and was unchanged during the follow-up period in the majority of patients. 17% of patients noted hypersensitivity of the donor site to a variety of stimuli such as cold or vibration. Hair formation was reported at the recipient site by 78% of patients. 83% of the patients found the flap to be bulky and 15% had undergone at least one procedure for debulking. We recommend that the use of the lateral arm flap should be limited to males and cases in which the resulting donor site can be closed primarily.     

Physiological differences for distinct somatic sensory modalities and sweating among the donor sites of cutaneous and fasciocutaneous free flaps

Differences of sensation and sweating among the typical sites of cutaneous and fasciocutaneous flaps (scapular, lateral arm, radial forearm, groin and dorsalis pedis) were assessed in 30 healthy volunteers (20 males and 10 females) aged 17-62 years (mean 38.2 years). Standard clinical methods were used: Semmes-Weinstein monofilaments for testing light touch threshold, discriminator and blunt caliper for evaluation of static and dynamic two-point discrimination and the Marstock quantitative method for assessing the normative values of warm-cold difference limen and heat and cold pain thresholds. Spontaneous sweat secretion was observed and documented by the ninhydrin test. We established various physiological differences for distinct somatic sensory modalities and sweating among the body regions (donor sites of cutaneous and fasciocutaneous free flaps).     

The sensory potential of free flap donor sites

Microneurovascular techniques make transfer of innervated soft tissue a reality. The present study investigated the sensory potential of four such donor sites: volar wrist, dorsal hand, dorsal foot, and great toe. Normal moving and static two-point discrimination values for these areas are reported. A sensory reeducation protocol demonstrated that even these normal values may be improved with training. This suggests that the full potential of transferred innervated soft tissue may best be achieved by incorporating sensory reeducation routinely in the postoperative rehabilitation program.     

Free microvascular tram flaps: report of 185 breast reconstructions.

The free TRAM flap is the most elegant technique currently available for breast reconstruction. We describe here the surgical technique, the complications, the possible effects of the prognosis of the breast cancer, and the learning curve of the surgical team. From December 1990 to the end of 1995 we reconstructed 185 breasts (10 bilateral) in 175 patients with free TRAM flaps; 27 were immediate reconstructions. We harvested the flap based on the inferior epigastric pedicle on the opposite side to the affected breast. To dissect the rectus muscle we used a muscle-sparing technique. The flap was designed and de-epithelialised while still on the abdomen, and was anastomosed to the thoracodorsal or circumflex scapular vessels with loupes only. In the immediate reconstructions we removed the breast tissue through a periareolar incision; we dissected the group I axillary lymph nodes and exposed the recipient vessels through a separate incision. The areolar complex was autotransplanted as a free skin graft. Only two flaps were lost. Eight patients were reoperated on for thrombosis of the vessels. The complication rate was nearly 50% among the first 50 patients. However, as surgical experience grew, the figure was reduced, eventually being down to 20%-25%. Of the patients who had delayed reconstructions only two died during the follow-up period of 48 months. One patient had a local recurrence above the TRAM skin. During the last eight years the free TRAM flap has been our main method of breast reconstruction. Free flaps today are reliable and the reconstruction does not seem to worsen the prognosis of breast cancer.     

Functional evaluation of microvascular free flaps with positron emission tomography.

BACKGROUND: The aim of this study was to assess blood flow (BF) of microvascular free flaps studied with positron emission tomography (PET) in patients with head and neck squamous cell cancer (HNSCC) undergoing major radical surgery 3-4 weeks after high-dose radiotherapy. METHODS: Five patients underwent resection of the HNSCC of the oral cavity followed by microvascular reconstruction with a radial forearm flap. Regional BF in oral and neck tissues was measured with PET using radiolabelled water ([15O]H2O) twice (1-2 and 12-14 days, respectively) following radical surgery. RESULTS: In the first postoperative PET study, the median BF in the cutaneous flap area was 5.1 mL/100 g/min, and in the muscle contra-lateral to the recipient site 19.9 mL/100 g/min. A low flap-to-muscle BF ratio appeared to correlate with circulatory incongruity, and thus with poorer flap success. The follow-up study on the second postoperative week supported the results of the primary PET scan. CONCLUSIONS: This pilot study suggests that PET using [15O]H2O is a feasible method to quantitatively evaluate BF of the whole free flap in patients operated on for oral     

Use of free flaps for covering deep burns in functional sites

From July 1980 to July 1988, 10 free flaps were used to cover deep burn on wrist, elbow, heel and hand. The wounds can be closed in time and the functions can be rehabilitated early. The results were not satisfied if the traditional methods were used to cover the infected and necrotic muscle, tendon, nerve, blood vessel, bone and joint due to electric, hot compressed or flame burns. The choice of using free flaps should be very careful because the operation time is relatively longer, the procedure is more complex, and the general condition of the patient may be interfered. The more serious results may be got if the free flap does not survive. It is recommended to use antero-lateral femoral free flap, because the sites of blood vessels are constant, the donor area can be hidden from view, the thickness and softness are satisfied.     

Blood flow in free muscle flaps measured by color Doppler ultrasonography

Color Doppler ultrasonography, a noninvasive method for studying changes in blood flow, has been used to monitor 18 patients with free microvascular lower limb muscle flaps. The peak, mean, and minimum velocities, resistance indices, and diameters of the flap pedicle arteries and also of the limb recipient arteries proximal to the microvascular anastomoses were measured at 2 and 6 weeks and 3, 6, and 9 months after surgery. The peak velocities did not significantly differ from each other, but the mean velocity in the flap pedicle arteries was 12.5% higher than that in the recipient arteries throughout the study period. End diastolic velocity in the pedicle was positive (toward the ultrasound probe) at 2 weeks (mean, 2 cm/sec, SD 10), 6 weeks (mean, 5 cm/sec, SD 16), and 3 months (mean, 3 cm/sec, SD 13) after surgery and significantly higher (P<0.05) than at 6 months (mean, 7 cm/sec, SD 11), when the pattern of blood flow was normal forward/backward flow during systole/diastole. The resistance indices of the pedicle at 2 weeks (Ri = 0.978), 6 weeks (Ri = 0.936), and 3 months (Ri = 1.001) were significantly lower (P<0.05) than at 6 months (Ri = 1.108), when the pedicle and recipient artery indices were the same. The diameter of the pedicle arteries was 14% smaller than those of the recipient arteries, but did not change during follow-up. This prospective clinical study shows that blood flow in the pedicle of a free microvascular muscle flap is increased until 6 months after surgery, mainly due to the increased minimum velocity of the pedicle in diastole and decreased resistance index. These findings can be attributed to the loss of vessel tone after denervation and are in accordance with earlier studies showing that denervated muscles lose their autoregulation and that blood flow increases, but that these phenomena subside with time. Increased blood flow in free muscle flaps can explain the high success rate of microanastomoses and positive effect on wound healing. © 1995 Wiley-Liss, Inc.     

Assessment of donor site morbidity for free radial forearm osteocutaneous flaps

Purpose: Assessment of donor site morbidity and recipient site complications following free radial forearm osteocutaneous flap (FRFOCF) harvest and evaluation of patient perceived upper limb disability for free radial forearm osteocutaneous versus fasciocutaneous flaps (FRFF). Methods: First a case series was undertaken of 218 patients who underwent an FRFOCF at two tertiary referral centers between February 1998 and November 2010. Outcomes included forearm donor site morbidity and recipient site complications. Second, the disability of the arm, shoulder, and hand (DASH) questionnaire assessing patient perceived arm disability was administered by phone to 60 consecutive patients who underwent an FRFOCF or FRFF. Results: Mean patient age was 63 years with male predominance (62.8%). Median bone length harvested was 8 cm (range, 3–12 cm) with prophylactic plating of the radius following harvest. Donor site morbidity included fracture (1 patient, 0.5%) and sensory neuropathy (5 patients, 2.3%). Mean DASH scores were comparative between groups and to established normative values. Mandibular malunion rate was 3.2% and hardware extrusion at the recipient site occurred in 15.6%. Conclusion: Reluctance to perform FRFOCF by surgeons usually centers on concerns regarding potential donor site morbidity and adequacy of available bone stock; however, we identified minimal objective or patient perceived donor site morbidity or recipient site complications following harvest of FRFOCFs. Mild wrist weakness and stiffness are common but do not impede ability to perform activities of daily living. Data from this and other reports suggest this flap is particularly useful for midfacial and short segment mandibular reconstruction. © 2012 Wiley Periodicals, Inc. Microsurgery, 2012.     

Laser Doppler surveillance of the circulation of free flaps and replanted digits

In a series of 40 clinical free flaps and replantations the laser doppler technique has been used successfully for postoperative surveillance of circulation. A uniform flow pattern was obtained from all uncomplicated cases contrasting to the flow pattern seen in cases with thrombotic complication. The laser doppler continuously records flow of the microcirculation and is able to monitor blood flow in all types of free tissue transfer presently used as well as replantations. The laser doppler has effectively diagnosed two arterial thromboses with a characteristic flow pattern. It can distinguish venous from arterial occlusion. It can record flow in skin flaps which are difficult to judge clinically and in buried flaps, where no clinical observations are possible. The laser doppler should be used in conjunction with routine clinical observations.     

Colour Doppler sonography of flaccid penis in evaluation of erectile dysfunction

BACKGROUND: Erectile dysfunction is a common and potentially treatable problem. Other than psychological, anatomical and metabolic factors, vasculogenic causes also play an important role in erectile dysfunction. Among the various diagnostic tools available for the diagnosis of vasculogenic causes, colour Doppler sonography is noninvasive, simple and promising. METHODS: This preliminary prospective study was conducted on 40 patients with erectile dysfunction, coming from a rural background to a hospital situated in a semi-urban setting. RESULTS: It was found that a cut-off value of 10 cm/second for peak systolic velocity in flaccid penis had the best accuracy among three chosen cut-off values, i.e. 5, 10, 15 cm/second, for detecting arterial insufficiency with sensitivity of 94.1%, specificity of 93.6%, negative predictive value of 98% and positive predictive value of 80%. CONCLUSION: Doppler sonography may be used as a good predictor of clinical response to intracavernosal injection of a vasodilating pharmacological agent.     

Venous endothelial changes after experimental cooling of free flaps

The free epigastric rabbit flap was used to observe morphological alterations in the microvasculature following prolonged hypothermic ischemic intervals. Free flaps were raised, cooled 1-6 days, and reanastomosed. The epigastric artery, vein, and dermal vessels were examined by electron microscopy. Efforts to keep flap tissues in the cold less than or equal to 5 days were successful (85% of flaps survived following reanastomosis N = 15). Flap failures were accompanied by extensive disruption to the endothelial cells of the epigastric vein. The findings support the efficacy of a cooling period less than or equal to 5 days for free flaps. The morphological alterations in the venous endothelium of the flap also suggest a plausible explanation for flap failures which occur in spite of patent anastomotic sites.     

Breast reconstruction with free flaps from the abdominal donor site: TRAM, DIEAP, and SIEA flaps

Multiple types of free flap can be elevated from the lower abdominal region for use in breast reconstruction. These include the free transverse rectus abdominis myocutaneous flap, the deep inferior epigastric artery perforator flap, and the superficial inferior epigastric artery flap. This sequence of flaps represents an evolution in the protection of the donor site. However, the decision as to which flap may be most appropriate for an individual patient is complex. This article serves to review pertinent surgical anatomy, preoperative planning, intraoperative decision making in flap elevation, and reported outcomes.