Hirudin enhances perforator flap survival: Clinical application report and mechanistic exploration.

BACKGROUND AND PURPOSE: Hirudin, a potent anticoagulant, is used in traditional Chinese medicine (TCM) to treat thrombotic conditions and prevent postoperative thrombosis. Coagulation-related vascular complications are a common cause of perforator flaps failure. This study explores hirudin's potential to enhance flap growth by mitigating coagulation-related issues. MATERIALS AND METHODS: Patients were divided into GroupⅠ(hirudin group) and GroupⅡ(control). Laboratory tests covered red blood cell count (RBC), hematocrit (HCT), platelet count (PLT), monocyte count (MONO), prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), and D-Dimer. Clinical parameters, including capillary refill time (CRT), flap swelling, and survival status, were evaluated. Animal experiments used Sprague-Dawley (SD) rats to establish random skin flaps. The experimental side received hirudin injection, while the control side received saline. Flaps were photographed to calculate survival rate, and CD31 immunohistochemical (IHC) analysis was performed to calculate microvessel density (MVD). RESULTS: The study, with 29 patients, found significant CRT differences between groups on postoperative days 2 and 6 (p = 0.027; p = 0.019), favoring GroupⅠ. Swelling severity varied significantly over time; GroupⅡhad more pronounced swelling. GroupⅠshowed superior flap growth with fewer complications, statistically significant (p = 0.033). Specific lab indicators (MONO, PT, and FIB) were significant at certain times. In animal experiments, the experimental side consistently had higher flap survival and slightly increased CD31 expression at various times, with higher MVD on days 2 and 6. CONCLUSIONS: Hirudin enhances flap survival through diverse mechanisms, supporting its role as a complementary approach in perforator flap surgeries.

Treatment of Advanced Male Genital Lymphedema With a Complete Functional Lymphatic System Pedicled Transfer.

OBJECTIVE: To evaluate the functional efficacy of the superficial circumflex iliac artery perforator (SCIP) -lymphatic pedicled flap in the treatment of advanced male genital lymphedema. METHODS: From February 2018 to January 2022, we treated 26 male patients with scrotal and penoscrotal advanced lymphedema using reconstructive lymphatic surgery. Isolated scrotal involvement was seen in 15 patients, and 11 patients had penoscrotal involvement. Excision of genital lymphedematous fibrotic tissue was followed by reconstruction utilizing the SCIP-lymphatic flap. Patient characteristics, intraoperative data, and postoperative results were evaluated. RESULTS: The mean patient age was 39 ± 4.6, and the mean follow-up time was 44.9 months. the SCIP-lymphatic flap was used to reconstruct partial (n = 11) or total (n = 15) scrotum and used to reconstruct total penile skin in 9 cases and partial in 2 cases. The flap survival rate was 100%. Cellulitis rates were dramatically reduced after reconstruction (P value <.001). The mean genital lymphedema score (GLS) after surgery was 0.05, which was significantly lower than the preoperative 1, 6.2 (P < .001). The median Glasgow Benefit Inventory (GBI) total score was +41, all 26 patients (100%) showed a degree of quality of life improvement. CONCLUSION: The pedicled SCIP lymphatic transfer approach in advanced male genital lymphedema can provide a durable complete functional lymphatic system that improves the appearance and genital lymphatic drainage. This leads to an improvement in quality of life as well as in sexual functions.

Effects of Preconditioning With Transcutaneous Electrical Nerve Stimulation Monitored by Infrared Thermography on the Survival of Pedicled Perforator Flaps in a Rat Model.

OBJECTIVE: Pedicled perforator partial or complete necrosis with a rate of 13.7%. This study was undertaken to test whether preconditioning with transcutaneous electrical nerve stimulation (TENS) monitored by infrared thermography protect against partial necrosis by converting the choke anastomoses to the true anastomoses via inducing heme oxygenase-1 (HO-1) in a rat pedicled perforator flap model. METHODS: Seventy-two Sprague-Dawley rats were randomly assigned to the control, the TENS, the TENS + SnPP (tin protoporphyrin; HO-1 activity inhibitor; 50 µmol/kg) and the TENS +0.9% saline groups. On the unilateral dorsum of the rats, a rectangular flap donor site of 11 × 3 cm was marked out, which contained three perforator angiosomes and two choke zones. On days 1, 3 and 4, 1 hour of TENS (biphasic pulses, 25 mA, 80 Hz, 200 µs) was applied to the flap donor sites, respectively. On day 5, after the flap donor sites were assessed by infrared thermography, the flaps were harvested based on the deep circumflex iliac artery perforator. RESULTS: Infrared thermography showed that the choke zones in the flap donor sites presented white in the TENS and the TENS +0.9% saline groups, whereas they presented red in the control and the TENS + SnPP groups. Postmortem arteriography showed that the number of arterioles across each choke zone significantly increased in the TENS and the TENS +0.9% saline groups compared with the control and the TENS + SnPP groups. Immunohistochemistry and western blot showed a significant increase in HO-1 in the choke zones after TENS preconditioning. The necrotic area percentage of the flaps was significantly decreased in the TENS (4.3% ± 2.6%) and the TENS +0.9% saline groups (4.5% ± 2.3%) compared with the control (24.8% ± 5.0%) ( P < 0.001); there was no significant difference between the TENS and the TENS + SnPP (24.4% ± 7.3%) groups. CONCLUSIONS: These data show that TENS preconditioning monitored by infrared thermography might be a promising strategy to prevent pedicled perforator flaps from partial necrosis.

Superior gluteal artery perforator flap salvaged via hyperbaric oxygen therapy.

The superior gluteal artery perforator (SGAP) flap can be challenging and in common with all flaps can develop venous and arterial insufficiency. Several prior studies have demonstrated the successful utility of hyperbaric oxygen therapy (HBOT) in the salvage of compromised flaps, mainly with deep inferior epigastric perforator, latissimus dorsi or transverse rectus abdominis myocutaneous flaps. SGAP flaps are autologous alternatives to abdominal-based flaps and provides adequate adipose tissue for breast reconstruction. We report a case of a woman in her 50s who underwent a delayed bilateral breast reconstruction using SGAP free flaps. Postoperatively, venous congestion of her right breast flap was noted for which she was referred for HBOT. An acceptable aesthetic result was achieved following 17 HBOT treatments. This is the first case we can find in the published literature of ischaemic SGAP free flap being salvaged by HBOT.

Effects of bradykinin on the survival of multiterritory perforator flaps in rats.

BACKGROUND: Bradykinin, a vasoactive peptide, has many biological functions. For example, it accelerates angiogenesis. Thus, we studied the effects of bradykinin on the survival of perforator flaps. METHODS: Averagely, 50 male Sprague-Dawley rats were divided into control and bradykinin groups and underwent procedures to the multiterritory perforator flap. Areas of flap survival were tested 7 days later. Flap perfusion was evaluated by laser Doppler imaging. We assessed the extent of autophagy by determining LC3-II/I, Beclin 1, and p62. Flap angiogenesis was assessed by immunohistochemistry and H&E staining. We measured the level of vascular endothelial growth factor (VEGF) protein using western blot. We assessed oxidative stress by measuring the activity of superoxide dismutase (SOD) and malondialdehyde (MDA) levels. The apoptotic index was also evaluated by western blot, and we determined nitric oxide (NO) production using an NO assay kit. RESULTS: The bradykinin group exhibited significantly larger areas of flap survival, higher blood supply, and more neovascularization. The bradykinin group also had higher SOD activity, higher VEGF expression and NO content, and reduced MDA compared to the control group. Rats treated with bradykinin also had lower levels of apoptosis and autophagy relative to the control group. CONCLUSION: Our results suggest that bradykinin promotes the survival of multiterritory perforator flaps by increasing angiogenesis, promoting the release of NO, suppressing apoptosis, reducing oxidative stress, and inhibiting autophagy.

Post-traumatic lymphedema treatment with superficial circumflex iliac artery perforator lymphatic free flap: A case report.

Post-traumatic lymphedema is poorly understood. It is rarely considered in limb reconstruction decision-making approach. We report a case of a 41-year-old female who presented with right upper extremity lymphedema after degloving injury and split thickness skin graft, successfully treated with a superficial circumflex iliac artery perforator (SCIP) free flap restoring the lymphatic drainage. Right upper extremity had an excess of 258.7 mL or an excess volume of 27.86% compared to the healthy contralateral limb. A SCIP free flap including lymphatic vessels (SCIP-L) was performed to replace the skin graft in order to restore the lymphatic flow. Flap size was 19 × 8 cm and pedicle length was 4 cm. No lymph nodes were included and no lymphatic or lymphovenous anastomoses were performed. The surgery was uneventful, and there were no postoperative complications. Fourteen days after free tissue transfer, lymphedema showed clear improvement. At a 4-month follow-up, 55.6% reduction of excess volume was obtained. Indocyanine green lymphography performed at that time showed a restitution of lymph flow through the flap. Lymphedema improvements persisted at a 6-month follow-up. A successful treatment of post-traumatic lymphedema can be performed by using the SCIP-L free flap for soft tissue reconstruction of critical lymphatic drainage areas.

Inhibition of autophagy after perforator flap surgery increases flap survival and angiogenesis.

BACKGROUND: The survival ratio of multiterritory perforator flap is variable. Therefore, surviving mechanisms are increasingly explored to identify novel therapeutics. The condition of the choke zone is essential for perforator flap survival. In this study, we investigated autophagy in the choke zone after flap surgery. MATERIALS AND METHODS: The flap model involved a perforator flap with three territories that was located on the right dorsal side of a rat. A total of 36 rats were divided into six groups, including the control, 0 d postoperative (PO), 1, 3, 5, and 7 d PO groups. In addition, 72 rats were divided into three groups, including a control group, a 3-methyladenine (3-MA) group, and a rapamycin group. Skin tissue of rats was used for measuring autophagy proteins, vascular endothelial growth factor (VEGF) expression, and histological examination. On day 7 after surgery, the survival ratio of each flap was determined. RESULTS: The expression of autophagy and VEGF in the second choke zone (choke II) was increased after flap surgery. Among the three groups, the survival ratio of flaps in the 3-MA group was the highest. Furthermore, the angiogenesis level in the 3-MA group in choke II was the highest among the three groups. CONCLUSIONS: Autophagy was initiated by surgery in choke II, and VEGF expression in choke II was increased after flap surgery. Inhibiting autophagy after perforator flap surgery is beneficial for flap survival and for promoting angiogenesis in choke II.

Indications for, and limitations of, the retroangular flap in facial reconstruction according to its vascular mapping.

We have used the retroangular flap for the reconstruction of facial defects after excision of tumours. Important variables such as vascular mapping, type of anaesthesia, duration of stay in hospital, and the diagnosis and treatment of complications were taken into account in assessing its effectiveness. We studied 187 patients, 103 men and 84 women, who were treated with the retroangular flap, and the morphological and cosmetic results analysed. There are many vascular variations of the flap The patients were followed up for a median of 12 (range 12-125) years and their reconstructions were successful. The technique can be considered as one of first methods of choice for the reconstruction of cutaneous defects of the middle third of the face.