Difference In Flap Survival Research Articles

VEGF and Other Gene Therapies Improve Flap Survival-A Systematic Review and Meta-Analysis of Preclinical Studies.

Surgical flaps are basic tools in reconstructive surgery. Their use may be limited by ischemia and necrosis. Few therapies address or prevent them. Genetic therapy could improve flap outcomes, but primary studies in this field present conflicting results. This systematic review and meta-analysis aimed to appraise the efficacy of external gene delivery to the flap for its survival in preclinical models. This review was registered with PROSPERO (CRD42022359982). PubMed, Embase, Web of Science, and Scopus were searched to identify studies using animal models reporting flap survival outcomes following any genetic modifications. Random-effects meta-analysis was used to calculate mean differences in flap survival with accompanying 95% CI. The risk of bias was assessed using the SYRCLE tool. Subgroup and sensitivity analyses were performed to ascertain the robustness of primary analyses, and the evidence was assessed using the GRADE approach. The initial search yielded 690 articles; 51 were eventually included, 36 of which with 1576 rats were meta-analyzed. VEGF gene delivery to different flap types significantly improved flap survival area by 15.66% (95% CI 11.80-19.52). Other interventions had smaller or less precise effects: PDGF-13.44% (95% CI 3.53-23.35); VEGF + FGF-8.64% (95% CI 6.94-10.34); HGF-5.61% (95% CI 0.43-10.78); FGF 3.84% (95% CI 1.13-6.55). Despite considerable heterogeneity, moderate risk of bias, and low quality of evidence, the efficacy of VEGF gene therapy remained significant in all sensitivity analyses. Preclinical data indicate that gene therapy is effective for increasing flap survival, but further animal studies are required for successful clinical translation.

Hyperbaric Oxygen Therapy in Plastic, Aesthetic, and Reconstructive Surgery: Systematic Review

Introduction: Hyperbaric oxygen therapy (HBOT) has been used over the past six decades to treat multiple conditions. This systematic review aims to identify and evaluate the clinical outcomes of hyperbaric oxygen therapy in the field of plastic, reconstructive, and aesthetic surgery, found in the literature from the year 2000 to the present. Methods: A systematic review of the literature focused on the conceptual and methodological aspects of the PRISMA Declaration. The search for clinical trials focused on the results of hyperbaric therapy in plastic, reconstructive, and cosmetic surgery. The Newcastle–Ottawa scale suggested by the Cochrane manual was applied to each study. The study was carried out with a defined protocol and was registered in PROSPERO, with code CRD42022301261. Results: From the 170 articles identified, 6 were selected. Five of them showed that hyperbaric oxygen therapy favored the reduction of the size of skin ulcers and increased the formation of granulation tissue (two trials; p < 0.05), increased the partial pressure of transcutaneous oxygen in patients with free flaps (one trial; p < 0.001), reduced perfusion in keloid scarring disorder (one trial; p < 0.01), and accelerated both the fading of melanin pigmentation and the decrease in age spot size (one trial; p < 0.05). The methodological quality was moderate in all cases because there was no blinding method reported. One study failed to find differences in flap survival, time to resolution of venous congestion, resolution of edema, and postoperative recovery period (p > 0.05). Conclusions: Hyperbaric oxygen therapy has been increasingly used in the field of plastic and reconstructive surgery, and has shown potential benefits in promoting wound healing, reducing the risk of infection, and improving the survival of tissues used in reconstructive procedures. Further research with more rigorous clinical trials is needed to fully understand the efficacy and optimal use of this therapy in the field of plastic and reconstructive surgery.

Outcomes of Local versus Free Flaps for Lower Extremity Trauma.

Lower extremity reconstruction often requires soft tissue transfer for limb salvage. Flaps are allocated based on injury size, location, and shape coupled with surgeon expertise. Ideally, vascularized tissue should have similar outcomes across local and free tissue transfers. By evaluating outcomes from a Level 1 trauma center, we aim to provide recommendations regarding surgical management of leg reconstruction with respect to local versus free flap implementation. This retrospective review evaluated patient medical history, demographics, flap characteristics, and outcomes from LAC + USC between 2007-2021 using an internal database. Outcomes included failure rates, complications, and ambulation. 357 lower extremity flaps were placed on 322 patients; 187 (52.4%) were local and 170 (47.6.%) were free flaps. Twenty-one (11.2%) local flaps suffered significantly more postoperative hardware infections and/or osteomyelitis compared to nine (5.3%) free flaps. Eleven (5.9%) local flaps developed partial necrosis, four requiring revision; 12 (6.4%) total local flaps required revision. Comparatively, sixteen (9.4%) free flaps developed partial necrosis, seven requiring revision; 18 (10.6%) total free flaps required revision. Flap survival was 96.3% for local versus 93.5% for free flaps. Percentage of fully ambulatory patients and time to final ambulation was not significant across cohorts. Local flaps may portent higher risk for infection; though the cause is not clear, the results may be confounded by comorbidities. Nevertheless, there were no significant differences in flap survival or number of fully ambulatory patients across cohorts. Future studies should evaluate aesthetic results and patient satisfaction across flap types.

Effects of different scar types on flap viability in a skin flap model: an experimental study.

The purpose of this study was to investigate the use of tissues with multiple traumas, scarred pedicles, and medial scarring as a flap. Forty-eight rats were randomly divided into four equal groups. The modified McFarlane flap was chosen as the flap model. In Group 1 (control), a dorsal skin flap was elevated and then sutured back into original position. In the other groups, a two-phase procedure was used. In Group 2 (pedicle incision), scar tissue was created with a skin incision at the prospective pedicle site of the flap and then sutured to its original site. In Group 3 (preconditioning), multiple full-thickness traumas were performed along the entire flap body, and in Group 4 (middle incision) scar tissue was created with a skin incision at the prospective middle region of the flap. Then, after 45 days, dorsal flaps were raised in all rats and then sutured back into position. Seven days later, flap survival was evaluated through microangiography and histological evaluation of flap segments. Histopathological examination included assessment of the number of vessels, necrosis, infiltration with polymorphonuclear leukocytes, edema, fibrosis, inflammation, increase in fibroblast activity, and neovascularization. The flap survival rates were 66.78% in Group 1, 68.05% in Group 2, 68.5% in Group 3, and 60.01% in Group 4. The flap survival rate was significantly lower in Group 4 (p < 0.05). There was no significant difference in flap survival between Groups 1, 2, and 3. On microangiographic examination, the vascular network extended more distally and was densest around the scar line in Group 2. Vascularization was poorest in Group 4. On histological examination, the number of vessels tended to be greatest in Groups 3 and 4 but this was not significantly different between groups (p < 0.05). The study findings showed that it may be possible to raise a flap from a previously mutilated site secondary to scar formation and multiple full-thickness traumas along the flap body. However, distal necrosis may occur in situations when the scar is positioned in the middle region of the prospective flap.

Free tissue transfers for reconstruction of weight-bearing heel defects: Flap selection, ulceration management, and contour revisions

Soft tissue defects in the weight-bearing heel represent a reconstructive challenge because of tissue complexity and lack of local/regional coverage. This study presents our reconstruction outcomes of different defect aetiologies, reconstruction timing, and flap selection. Patients with weight-bearing heel defects who underwent free tissue transfer from 2003 to 2014 and with at least 6 months of follow-up were retrospectively reviewed. Flap types (fasciocutaneous vs muscle/musculocutaneous), timing of reconstruction (early vs subacute vs delayed), and defect aetiology were compared in terms of flap failure, vascular complications, and ulceration. Seventy-four flaps were used to reconstruct weight-bearing heel defects in 70 patients. Defect aetiology included trauma in 53 patients (75%), chronic wound in 12 patients (17%), and tumour resection in 6 patients (8%). Flap survival was 97% (72/74). There was no significant difference in flap failures between muscle and fasciocutaneous flaps. The timing of reconstruction showed no difference in flap survival. There was a significant difference in ulceration rate between the trauma and non-trauma groups (p=0.001). Twenty-eight ulcers (39%) developed, 12 (43%) of which presented 3 years postoperatively, while only 6 cases (21%) presented within one year postoperatively. Our experience represents one of the highest survival rates reported regarding free flap weight-bearing heel reconstruction. The anterolateral thigh flap was our first choice for extensive heel defects. Ulceration incidence was directly related to trauma and tends to develop 3 years after reconstruction. Delayed reconstruction was at least as safe as early or subacute reconstruction though with less need for debulking.

Differences in free flaps' reconstructions with and without coupling device for venous anastomosis.

<br><b>Introduction:</b> Introduction of the coupler devices for anastomoses of neck vessels changes planning and performance of the surgical procedures. The Rigid ring of the coupling devices keeps a vein open and less prone to occlusion. Therefore, this should improve the flap survival rate and surgery duration.</br> <br><b>Aim:</b> The aim of the study was to point out the differences in surgery planning between couplers and sutures for venous microsurgical anastomoses.</br> <br><b>Methods:</b> The medical records of 209 patients who underwent 212 microvascular free flap reconstructions from January 2011 till December 2017 were retrospectively analyzed; 103 received radial forearm free flap (RFFF); 43 - anterolateral thigh flap (ALTF); 51 - fibula free flap (FFF); 15 - iliac crest free flap (ICFF). In 189 cases, reconstruction was performed simultaneously with tumor resection and in 23 cases, reconstruction was secondary, after previous oncological treatment. Among 443 anastomoses, suturing was used for 212 arteries and 127 venous anastomoses, while coupling was used for 104 venous anastomoses.</br> <br><b>Results:</b> The mean surgery duration for suturing was 452.82 min vs 358.88 min for coupling (P<0.05). Differences in flap survival and partial necrosis rates between coupling and suturing groups were not statistically significant (P>0.05). Donor vessel distribution in the neck was significantly different in both groups. Estimated costs of the surgical procedures performed with and without coupler devices were not equal.</br> <br><b>Conclusions:</b> The use of couplers for venous anastomosis in free flap head and neck reconstructions impacts the surgery process by shortening surgery duration which leads to cost reduction.</br&gt.

Muscle Cuff in Distal Pedicled Adipofascial Sural Artery Flaps: A Retrospective Case Control Study.

Background:Amputation after open tibial fracture occurs in 3% of cases. The rate increases when flap reconstruction is required. The standard care involves microsurgical tissue transfer although the pedicled reverse sural artery adipofascial flap (PRSAF) is a local alternative in patients endangered by a prolonged operative time. Incorporation of a gastrocnemius muscle cuff in this flap can be used to fill dead space and increase healing potential. Literature shows superior survival rates for both PRSAF and inclusion of a muscle cuff in comparison with the cutaneous version. The aim of the study was to compare the outcome of the PRSAF and the musculoadipofascial version (PRSMAF). We hypothesize that the PRSMAF provides similar lap viability and flap-related complication rates as does the adipofascial version. The muscle component may reduce the long-term osteomyelitis rate.Methods:Patients were evaluated retrospectively after reconstruction with either PRSAF or PRSMAF. Preoperative osteomyelitis, flap survival, complications and osteomyelitis clearance were analyzed.Results:The study shows preliminary results supporting the potential use of the PRSMAF. We compare either 23 PRSMAF or 20 PRSAF flaps. We found no statistically significant differences in flap survival or in complication rate.Conclusions:Although the anatomical situation may sometimes dictate the use of a free flap, a technically less-complicated option may in some cases offer a viable alternative. This study shows that the PRSMAF can serve as an alternative for complex bone defects in the limb, though it does not provide statistical improvement to the PRSAF.

Effects of Ischemic Preconditioning and C1 Esterase Inhibitor Administration following Ischemia-Reperfusion Injury in a Rat Skin Flap Model.

Ischemia-reperfusion (I/R) injury is a serious condition that can affect the success rate of microsurgical reconstructions of ischemic amputated limbs and complex tissue defects requiring free tissue transfers. The purpose of this study was to evaluate the effects of ischemic preconditioning (IPC) and C1 esterase inhibitor (C1-Inh) intravenous administration following I/R injury in a rat skin flap model. Superficial caudal epigastric skin flaps (3 cm × 7 cm) were performed on 50 Wistar rats that were randomly divided into five groups. Ischemia was not induced in the control group. All other flaps underwent 8 hours of ischemia prior to revascularization: I/R control group (8-hour ischemia), IPC group (preconditioning protocol + 8-hour ischemia), C1-Inh group (8-hour ischemia + C1-Inh), and IPC + C1-Inh group (preconditioning protocol + 8-hour ischemia + C1-Inh). Survival areas were macroscopically assessed after 1 week of surgery, and histopathological and biochemical evaluations were also measured. There were no significant differences in flap survival between the treatment groups that were suffering 8 hours of ischemia and the control group. A significant increase in neovascularization and lower edema formation were observed in the IPC group compared with that in the I/R group. Biochemical parameters did not show any significant differences. Intravenous administration of C1-Inh did not significantly modulate I/R-related damage in this experimental model, but further research is needed. On the other hand, IPC reduces tissue damage and improves neovascularization, confirming its potential protective effects in skin flaps following I/R injury.

Should 1 or 2 Venous Anastomoses Be Done in Microsurgical Flap Transfer?

Venous compromise is still the most common cause of free flap failure. The need of a second venous anastomosis to prevent free flap failure is controversial. It is proposed that the use of dual venous anastomoses reduces venous compromise. However, some surgeons suggest that dual venous drainage reduces venous blood flow causing a potential risk of thrombosis. This study aimed to compare the frequency of reexploration secondary to venous thrombosis in free flap surgeries in reconstruction of soft tissue defects with 1-vein versus 2-vein anastomosis. We performed a retrospective cohort study including 298 flaps. In 180 of these patients, 2-vein anastomosis was done, and in 118, 1-vein anastomosis was done. The study was conducted at Aga Khan University Hospital from January 2017 to December 2018. The number of venous anastomosis was not associated with flap survival. The group with dual anastomosis required more frequent reexploration as compared with 1 venous anastomosis group (8% vs 1.7%).Outcome and salvage rate were better in the 2-vein group as compared with the 1-vein group (64% vs 50%). There is no difference in flap survival in single or dual venous anastomosis, but we have noticed higher reexploration rates in the 2-vein group. However, outcome is better in the 2-vein group.

Single Versus Simultaneous Double Free Flaps for Head and Neck Reconstruction: Comparison of Flap Outcomes and Donor-Site Morbidity.

Ablative procedures of the head and neck often result in substantial defects that require large-volume tissue transfer for restoration of form and function. Multiple simultaneous free flaps may be required for complex defects, but these procedures are often avoided because of the perception of an increase in associated surgical complications and morbidity. We present our experience with the use of simultaneous multiple free flaps as compared with single free flaps (SFFs) for head and neck reconstruction. Thirty-seven patients with a history of head and neck malignancy underwent SFF reconstruction, and 21 patients underwent double free flap (DFF) reconstruction. Statistical analysis was conducted comparing demographics, comorbidities, etiology of disease, and surgical outcomes between the 2 patient groups. Operative time and length of hospital stay were both significantly longer in the DFF group versus the SFF group. Despite significantly higher rates of preoperative radiation, osteoradionecrosis, and operation for secondary malignancy in DFF group, no significant differences in flap survival, partial flap loss, recipient site complications, or donor site complications were found. Overall flap-related reoperation rates were low, as were total flap losses. There were 10 complications (24%) that required reoperation in the DFF group, and 1 total flap loss (2.4%), on per-flap basis. There were 10 complications (27%) that required reoperation in the SFF group and 3 total flap losses (8.1%). Per-flap incidence of donor site morbidity in the DFF group was significantly lower than that in the SFF group (23.8% vs 56.8%, respectively, P = 0.011). The use of multiple free flaps for reconstruction of major head and neck tissue defects is sometimes necessary to achieve adequate reconstructive results. These procedures have no significant associated increase in overall flap-related complications. Our findings suggest that donor site morbidity can be minimized in double-flap reconstructions by thoughtful flap selection.

Random flap survival with hyperbaric oxygen: daily versus twice-daily treatments

Hyperbaric oxygen (HBO₂) therapy is used to improve the survival of compromised flaps. Compromised flaps are complications encountered postsurgically, or in traumatic degloving or avulsion injuries. Failed flaps lead to persistence of the defect, requirement of another donor site, and psychosocial sequelae. Although evidence of the benefit of HBO₂ therapy is significant, there is no consensus on the optimal treatment regimen. The purpose of this study is to examine whether twice-daily treatments (BID HBO₂) provide additional benefit compared to daily treatments (QD HBO₂) in a rat compromised random flap model. A rat random flap model was used with subjects divided into three groups: 1) control group; 2) QD HBO₂; and 3) BID HBO₂, where HBO₂ was performed with 100% oxygen at 2.5 atmospheres absolute/ATA (253 kPa) for 90 minutes. After 10 days, areas of flap necrosis were measured and biopsies were taken for histologic analysis. Statistical analysis was performed using ANOVA and paired t-tests. A P-value ⟨0.05 was considered significant. Both treatment groups had significantly increased mean flap survival compared to controls (P⟨0.05). There was no significant difference in flap survival between the QD and BID groups. Capillary proliferation in the QD group was increased compared with controls. Both QD and BID HBO₂ protocols can significantly decrease random flap necrosis. However, the results of this study suggest there is no additional benefit gained with BID treatments. Clinical studies are warranted to confirm these findings and assist in formalization of protocols for the use of HBO₂in treating compromised random flaps.

Immediate application of vacuum assisted closure dressing over free muscle flaps in the lower extremity does not compromise flap survival and results in decreased flap thickness.

BackgroundFree muscle flaps are a mainstay for reconstruction of distal third leg wounds and for large lower extremity wounds with exposed bone. However a major problem is the significant postoperative flap swelling, which may take months to resolve. We studied the efficacy and safety of immediate application of a vacuum assisted closure (VAC) dressing after a free muscle flap to the lower extremity.MethodsOver a 19 months period, all consecutive free muscle flaps for lower extremity reconstruction at a Level I trauma center were evaluated prospectively for postoperative flap thickness, complications and flap survival. Immediate application of a VAC dressing was performed in 9 patients, while the flap was left exposed for monitoring in 8 patients.ResultsThere was no statistically significant difference in flap survival between both cohorts. Mean flap thickness at postoperative day 5 for the VAC group was 6.4±6.4 mm, while flap thickness for the exposed flap group was 29.6±13.5 mm. Flap thickness was significantly decreased at postoperative day 5 for the VAC dressing group.ConclusionsImmediate application of VAC dressing following free muscle flaps to the lower extremity does not compromise flap survival or outcomes and results in decreased flap thickness and a better aesthetic outcome.

The Use of Vasopressors in Pedicled Flaps for Chest Wall Reconstruction.

The effect of vasopressors on flaps remains controversial in the literature. Often, surgeons avoid vasopressors with the thought that vasoconstriction reduces flap perfusion resulting in flap loss. A retrospective review was performed on patients who required chest wall reconstruction from 1998 to 2013. Patients were identified through the use of Current Procedural Terminology codes. The data collected included demographics, indications for surgery, prior debridement, preoperative albumin levels, and perioperative vasopressor use. Outcomes measures included flap survival, flap complications, reoperation rates, intensive care unit length of stay, and mortality. Of the 1220 patient records reviewed, 88 had chest reconstruction by a plastic surgeon. Twenty-one patient records were excluded due to incomplete data. One patient experienced complete flap loss; these data were excluded from statistical analysis. Fifty patients received perioperative vasopressors whereas 15 did not. There was no significant difference in flap survival or loss between groups who received perioperative vasopressors and those who did not receive vasopressors. Age, intensive care unit length of stay, flap complications, and reoperation rates were significantly higher in those with partial flap survival. Perioperative vasopressor use does not adversely affect the outcome of pedicled flaps for chest wall reconstruction. Further research is warranted to review the effects of vasopressor dose and type on pedicled flaps.

Comparison of morbidity after reconstruction of tongue defects with an anterolateral thigh cutaneous flap compared with a radial forearm free-flap: a meta-analysis

Currently the radial forearm fasciocutaneous flap and the anterolateral thigh flap are among the most popular free flaps used for reconstruction of oral soft tissue. However, there is controversy about their efficacy after reconstruction of tongue defects because of their respective intrinsic properties, so we have compared them in reconstruction of tongue defects using meta-analysis. We conducted a search in Pubmed, EMBASE, OVID, Science Direct, the Cochrane Library, and Chinese National Knowledge Infrastructure, which covered all papers published before January 2015. Twelve clinical papers, that included 366 patients with 198 radial forearm flaps and 168 anterolateral flaps, met the criteria. Relevant data were extracted and analysed using systematic meta-analyses. The results showed that the incidence of localised numbness at the donor site of the radial forearm flap postoperatively was significantly higher and satisfaction with the appearance of the donor site significantly lower than in the anterolateral thigh group. There were no differences in flap survival, incidence of vascular crises in the flap, complications, satisfaction with the appearance of the tongue, or the postoperative clarity of speech and swallowing ability. Results suggested that the anterolateral thigh flap is the ideal soft tissue flap for reconstructing defects in the tongue, as there was minimal numbness at the donor site and patients were much more satisfied. Further research is needed to address details of the site and the extent of surgical defects as well as the relations between dissection of the radial flap and repair of the skin graft.

Outcomes of Breast Reconstruction After Mastectomy Using Deep Inferior Epigastric Perforator Flap After Massive Weight Loss.

Because of the correlation between breast cancer and obesity, plastic surgeons may encounter patients requiring reconstructive breast surgery after massive weight loss (MWL). Use of redundant abdominal skin for deep inferior epigastric artery perforator (DIEP) flap in these patients is a novel concept whose value has not been adequately studied. Assess the outcomes of the DIEP technique for breast reconstruction in the massive weight loss population. From 103 breast reconstruction patients having 150 DIEP flap procedures, 9 DIEP flaps were performed in MWL patients. Propensity score matching was used in a 1:2 ratio. Eighteen nonweight loss (NWL) patients were selected for comparison with 9 DIEP flaps performed in 6 MWL patients. Patients in 2 groups were matched for age and body mass index (BMI). Massive weight loss patients were compared with NWL patients on the basis of immediate versus delayed reconstruction and history of radiation; DIEP flap characteristics, including coupler size, additional venous anastomosis, need for re-exploration, and flap loss; length of hospital stay; abdominal wound healing complication; and hernia or bulging. There was no difference in the incidence of flap failures, bulging, or hernias requiring surgery in the MWL group. Additionally, there was no statistical difference in flap survival, abdominal complications, hospitalization days, operative time, or operative characteristics between the 2 groups. There was a significant positive correlation between immediate wound healing complications and comorbidities (P = 0.041). However, there was no correlation between wound healing complications and weight loss history. Only 6 MWL patients of a single surgeon were studied. For breast reconstruction after mastectomy, DIEP flaps can be used in MWL and NWL populations with equal flap success and abdominal donor site results. Therefore, cosmetic surgeons performing contouring procedures should consider sparing redundant abdominal tissues in patients requiring breast reconstruction.

The Paramidline Forehead Flap: A Clinical and Microanatomic Study.

The traditional paramedian forehead flap (FHF) is an axial flap based on the supratrochlear artery (STA). Doppler examination is often used to ensure inclusion of the STA within the flap. The authors hypothesized that a FHF pedicle design could be simplified to extend from the midline of the glabella to 1.2 cm lateral to the midline without compromising outcomes. To compare clinical outcomes and vessel densities of 2 FHF designs. Two FHF designs were used to repair fifty nasal defects. One was based on Doppler identification of the STA; the other on clinical measurements from the glabellar midline (with no effort to identify the STA). Clinical outcomes, complication rates, and pedicle vasculature of both groups were compared. There was no significant difference in flap survival or complication rate. Forehead flaps designed on the paramidline glabella had more arteries within their pedicles than Doppler-based FHFs (p < .05). Small arteries predominated, whereas larger arteries were infrequent in both groups. Size and number of arteries were not related to flap survival. A paramidline FHF has equivalent clinical outcomes as a flap based on the STA. A simple and reproducible design of the FHF using only surface landmarks is described.

Bilirubin provides perforator flap protection from ischaemia-reperfusion injury in a rat model: a preliminary result.

The use of bilirubin, a well-known and powerful antioxidant, has gained popularity in recent years because of its role in the prevention of ischaemic heart disease in patients with Gilbert's syndrome. We investigate the effects of bilirubin on ischaemia-reperfusion (I/R) injury using a rat perforator flap model. Forty-eight rats were randomly divided into two groups: experimental (bilirubin) group (n = 24) and control group (n = 24). In each group, elevated bilateral deep inferior epigastric perforator (DIEP) flaps were created. The right (no ischaemia side) and left (ischaemia side) DIEP flaps were separated according to the presence of ischaemia induction. Ischaemia was induced in anaesthetised rats by perforator clamping for 15 or 30 minutes. After surgery, the flap survival was assessed daily on postoperative days 0 to 5, and overall histological changes of DIEP flaps above the perforator were analysed at postoperative day 5. The flap survival rate in the bilirubin group was significantly higher than that in the control group at the ischaemia side following perforator clamping for 15 or 30 minutes (93·42 ± 4·48% versus 89·63 ± 3·98%, P = 0·002; and 83·96 ± 4·23% versus 36·46 ± 6·38%, P < 0·001, respectively). The difference in flap survival between the two groups was the most prominent on the ischaemic side following 30 minutes of perforator clamping. From a morphologic perspective, pre-treatment with bilirubin was found to alleviate perforator flap necrosis caused by I/R injury in this experimental rat model.

Laser resurfacing of skin flaps: an experimental comparison of three different lasers

Objective. The influence of Coherent Ultrapulse, TruPulse and Erbium:YAG laser skin resurfacing on survival of the skin flaps whenperformed simultaneously was evaluated. Material and methods. Weused twelve female Yucatan minipigs in the study. Skin flaps includingpaniculus carnosus were raised on the animals’ back. The flaps weresutured into the defect under tension. We designed 4 experimentalgroups: Control-Flaps only, Group 2-Flaps + 4 immediate TruPulselaser passes, Group 3-Flaps + 2 immediate Coherent UltraPulse laserpasses, Group 4-Flaps – immediate 50J/cm2 total fluence with Erbium:YAG laser. Results. Flap survival in Control group was 98.8%. Therewas no flap in Group 2 with complete survival. Survival of the flaps inGroup 2 (Tru-Pulse) ranged from 75-90%, with average flap survivalarea of 85.2%. In Group 3 (UltraPulse) all 24 flaps had some area of necrosis.Flap survival in Group 3 ranged from 75-95%, with an averageof 85.6%. In Group 4 (Erbium: YAG) flap survival area ranged from70-95%, with all 24 flaps with some area of necrosis, with average flapsurvival area of 87.3%. There is a significant statistical difference inflap survival area between groups 2, 3 and 4 versus Control (p&lt;0.001).Conclusion. The results of our study suggest that laser resurfacing ofskin flaps sutured under tension in the same operative session is detrimentalfor skin flap survival. We also found no significant differencein flap survival area between TruPulse, Coherent UltraPulse and Erbium:YAG laser treated flaps.

Effect of Recombinant Human Growth Hormone on Random Pattern Flaps in Rats

Recombinant human growth hormone, a very potent anabolic hormone, plays a significant role in growth regulation, bone metabolism, and wound healing. This study evaluates its effect on random flap survival. Rats were randomly divided into 2 groups. A dorsal random flap, cephalically based, was used. One group received 5 mg/kg subcutaneous injection of recombinant human growth hormone 1 hour before surgery and a repeat dosage every 24 hours for 1 week. The others served as controls. At the end of 1 week, average weight and flap survival was evaluated. There was no difference in flap survival between the groups. Treated rats had gained significantly more weight. Recombinant human growth hormone had no beneficial effect on flap survival. The lack of a deleterious effect of the hormone on random flap survival and its significant effect on rat weight and well being supports its safe use during flap surgery.

The Efficacy of Prophylactic Low-Molecular-Weight Heparin to Prevent Pulmonary Thromboembolism in Immediate Breast Reconstruction Using the TRAM Flap

Sir: We read with great interest the recent publication by Kim et al. entitled “The Efficacy of Prophylactic Low-Molecular-Weight Heparin to Prevent Pulmonary Thromboembolism in Immediate Breast Reconstruction Using the TRAM Flap” (Plast Reconstr Surg. 2009;123:9–12). The authors compared a group of 450 patients receiving a free microvascular transverse rectus abdominis musculocutaneous (TRAM) flap without medical prophylaxis with 200 patients receiving low-molecular-weight heparin for prophylaxis of deep vein thrombosis, and found a significant decrease in asymptomatic pulmonary thromboembolism in the latter group. Because antithrombotic therapy may influence not only deep vein thrombosis but also anastomotic patency and the incidence of microvascular anastomosis thrombosis, we would like to ask the authors about the incidence of anastomotic failure, requiring surgical revision, in their series. Did the authors observe a reduction of either venous or arterial anastomotic thrombosis in the heparin group? Finally, did the authors observe a difference in flap survival between the two groups? In large studies of microvascular breast reconstruction, the incidence of anastomotic venous and arterial thrombosis is reported to be 1.5 and 0.6 percent, respectively.1 Arterial anastomotic thrombosis is associated with flap loss in 11.1 percent of the cases, whereas venous anastomotic thrombosis may lead to flap loss in 26.7 percent of these cases.1 In concordance with the results from Kim et al., these data suggest a need for medical prophylaxis of vascular thrombosis following microvascular free tissue transfer. However, postoperative anticoagulation and antiaggregation regimens are not standardized, and it is unclear which thromboembolic risk factors may contribute to anastomotic thrombosis. In this context, we would like to point out the possible role of hereditary thrombophilia in postoperative thrombosis of both deep leg veins and microvascular anastomosis. Factor V Leiden mutation was first described in 1994 and has since been identified as a major risk factor for thromboembolic complications.2 Heterozygous carriers of the gene mutation carry a 5- to 10-fold higher risk for deep vein thrombosis, and the risk is 80-fold higher in homozygous carriers. In the white population, the prevalence of the factor V Leiden mutation is between 2 and 10 percent, thus resembling the most common type of hereditary thrombophilia in the Western world.2 We have recently published a case in which a patient with factor V Leiden mutation suffered from recurrent venous and arterial thrombosis at the microvascular anastomosis following breast reconstruction with a TRAM flap.3 Other authors also suggest a possible impact of factor V Leiden mutation on thrombotic occlusion of microvascular anastomosis.4,5 Because of the relatively high prevalence of factor V Leiden mutation in whites, further research on the impact of this thrombophilic disorder in patients undergoing free microvascular tissue transfer is warranted. Alexander E. Handschin, M.D. Kay Busch, M.D. Peter M. Vogt, M.D., Ph.D. Plastic, Hand, and Reconstructive Surgery Medical School Hannover Hannover, Germany