The Delay Phenomenon: Is One Surgical Delay Technique Superior?

Enhancing Skin Flap Survival with Preoperative Carbon Dioxide Fractional Laser Treatment: A Novel Approach in Reconstructive Surgery

BACKGROUND

Skin flap necrosis remains a significant challenge in reconstructive surgery, predominantly due to insufficient blood supply. Traditional methods like the surgical delay procedure, while effective, are invasive and associated with considerable patient discomfort and health care costs. This study explores the efficacy of Carbon Dioxide Fractional Laser (CDFL) treatment as a novel, less invasive alternative to enhance skin flap survival.

METHODS

Twenty-nine adult male Sprague-Dawley rats were divided into 2 groups: a CDFL treatment group (n=14) and a control group (n=15). The CDFL group received laser pretreatment 1 week before flap surgery, whereas the control group underwent flap surgery without pretreatment. Flap survival was assessed 7 days postsurgery using indocyanine green fluorescence angiography. In addition, histological analysis was conducted to evaluate tissue integrity, capillary density, and VEGF expression.

RESULTS

The CDFL-treated flaps showed significantly increased survival areas compared with controls (P<0.01). Histological evaluation revealed enhanced capillary dilation and increased VEGF expression in the CDFL group (P<0.05). Although capillary density was higher in the CDFL group, it did not reach statistical significance (P=0.052).

CONCLUSION

CDFL pretreatment significantly improves skin flap survival in rats, suggesting potential as a minimally invasive alternative to traditional surgical delay techniques. This approach could offer substantial benefits in reconstructive surgery, reducing patient morbidity and associated costs. Further studies are warranted to confirm these findings in clinical settings.

Electrical stimulation promoting the angiogenesis in diabetic rat perforator flap through attenuating oxidative stress-mediated inflammation and apoptosis

Background

Skin flap transplantation is one of the effective methods to treat the diabetes-related foot ulceration, but the intrinsic damage to vessels in diabetes mellitus (DM) leads to the necrosis of skin flaps. Therefore, the discovery of a non-invasive and effective approach for promoting the survival of flaps is of the utmost importance. Electrical stimulation (ES) promotes angiogenesis and increases the proliferation, migration, and elongation of endothelial cells, thus being a potential effective method to improve flap survival.

Objective

The purpose of this study was to elucidate the mechanism used by ES to effectively restore the impaired function of endothelial cells caused by diabetes.

Methods

A total of 79 adult male Sprague-Dawley rats were used in this study. Gene and protein expression was assessed by PCR and western blotting, respectively. Immunohistochemistry and hematoxylin-eosin staining were performed to evaluate the morphology and density of the microvessels in the flap.

Results

The optimal duration for preconditioning the flap with ES was 7 days. The flap survival area percentage and microvessels density in the DMES group were markedly increased compared to the DM group. VEGF, MMP2, and MMP9 protein expression was significantly upregulated. ROS intensity was significantly decreased and GSH concentration was increased. The expression of IL-1β, MCP‑1, cleaved caspase-3, and Bax were downregulated in the DMES group, while TGF-β expression was upregulated.

Conclusions

ES improves the angiogenesis in diabetic ischemic skin flaps by attenuating oxidative stress-mediated inflammation and apoptosis, eventually increasing their viability.

Surgical delay increases the survival of expanded random-pattern flap in pediatric patients

Despite the aid of tissue expansion, the ideal design of random pattern flap is not always available in patients with extensive skin lesions. We investigated the effectiveness of surgical delay on expanded flaps in pediatric patients. Retrospective cohort study was performed on patients who underwent tissue expansion surgery for extensive skin lesions at Seoul National University Children's Hospital. The surgical delay technique was employed for patients with unfavorable flap conditions related to location or transposition angles. The dimensions of skin lesions and flaps were measured based on medical photographs. Fifty patients underwent a total of 66 tissue expansion procedures (49 conventional procedures among 41 patients, 17 surgical delay procedures among 15 patients) from January 2016 to September 2019. Although flaps in the surgical delay group were more narrow-based (p < 0.001), the partial flap loss rate and excised area-to-inflation amount ratio was comparable between the two groups (p = 0.093 and p = 0.194, respectively). Viable flaps, excluding postoperative necrosis, in the surgical delay group were significantly more narrow-based in terms of the length-to-base width ratio and the area-to-base width ratio compared to conventional group (p < 0.01, p < 0.01). Surgical delay can result in outcomes comparable to well-designed random flaps, even in disadvantageous conditions. Patients with large skin lesions but limited areas for expansion may benefit from surgical delay.

The current state of knowledge on how to improve skin flap survival: A review

The incorporation of skin flaps in wound closure management with its cosmetic implications has appeared as a gleam of hope in providing desirable outcomes. Given the influence of extrinsic and intrinsic factors, skin flaps are prone to several complications, including ischemia-reperfusion injury (IRI). Numerous attempts have been undertaken to enhance the survival rate of skin flaps entailing pre/post-conditioning with surgical and pharmacological modalities. Various cellular and molecular mechanisms are employed in these approaches in order to reduce inflammation, promote angiogenesis and blood perfusion, and induce apoptosis and autophagy. With the emerging role of multiple stem cell lineages and their ability to improve skin flap viability, these approaches are increasingly being used to develop even more translationally applicable methods. Therefore, this review aims at providing current evidence around pharmacological interventions for improving skin flap survival and discussing their underlying mechanism of action.

Delayed axial flaps for coverage of a fourth degree scalp burn

Although free tissue transfers may be required to cover wounds of the head and neck with bone involvement and exposure, options lower on the reconstructive ladder should still be considered during the planning process. We present a case of an elderly gentleman with a history of cardiovascular comorbidity and neck radiotherapy, who sustained a deep flame burn injury to his scalp. Two delayed axial flaps, based on the superficial temporal and supraorbital arteries respectively, were used to obtain durable coverage of this complex wound.

The Africa Temporal Scalp Flap: a novel flap for facial reconstruction

Although a number of flaps exist for nasal reconstruction, severe scarring of the forehead after burn injury led to the development of a novel two-stage flap based on the superficial temporal artery (STA). The Africa Temporal Scalp (ATS) flap is composed of an axial ascending part on the STA, and a descending anterior extension for reconstruction of the mid face. This is a retrospective analysis of all patients who underwent ATS Flap surgery on the MV Africa Mercy. During the 7.5-year period, the ATS flap was applied to 45 facial reconstructions, with a median age of 28 years (range 19 months to 51 years). The main indications were previous burn injury (n=27, 60%) and noma (n=15, 33.3%). The majority of the flaps were used to reconstruct the lower third of the nose (n=39, 86.7%), and the remaining 6 were for the lips or cheek. Experience allowed for earlier division than three weeks depending on the length of the flap, and the recipient site. There was one partial flap loss, one infection requiring revision, and two injuries to frontal branch of the facial nerve. The ATS flap is a novel two-stage flap that has proved especially versatile when forehead flaps are unavailable for nasal reconstruction due to extensive forehead scarring. The ATS flap reliably provides ample supple skin, and the donor site is effectively obscured from view, located in the periphery of the face.

Effectiveness of Different Surgical Flap Delay Methods and Their Systemic Toxicities

OBJECTIVE

The surgical flap delaying has been shown to be effective in preventing partial flap loss or in preparing larger flaps. However, there is no gold standard flap delay method in the literature. In this study, the authors aimed to compare 3 types of surgical delay methods to determine which model would increase more flap survival. The authors also investigated the effect of delay methods on circulating mononuclear leukocytes as a parameter of DNA damage.

METHODS

Twenty-four Sprague-Dawley male rats were divided into 4 groups. All subjects had a 10 × 3 cm modified McFarlane flap. Surface area measurements, biopsies, and blood samples were taken on the day of sacrification; 7th day for the control group and 14th day for delay groups.

RESULTS

Between incisional surgery delay groups, a significant difference was found in necrosis and apoptosis in the bipedicled group, and only necrosis in the tripedicled group compared to the control. In terms of DNA damage, it was found higher in all experimental groups than in the control group.

CONCLUSIONS

Both incisional surgical delay procedures' results were meaningfully effective when only incisions were made without the elevation of flaps. In conclusion, bipedicled incisional surgical delay seems to be the most effective method in McFarlane experimental flap model whereas two-staged surgeries may increase the risk of systemic toxicity.

Effect of bone marrow mesenchymal stem cells on perforator skin flap survival area in rats

Trans-territory perforator flaps are commonly used to reconstruct large defects of the soft tissues. The distal portion of the flap often becomes necrotic, however, as a result of the jeopardised vasculature of choke zone II. The trophic and vascular regenerative properties of bone marrow mesenchymal stem cells (BMSC) seemed to be a promising approach to prevent flaps becoming ischaemic. The purpose of our study is to evaluate the effects of BMSC on the survival of the three-territory perforator flap. The flap model was created based on the deep circumflex iliac vessel in rats. Eighteen rats were distributed, at random, into three groups. Immediately after the flaps were placed, groups were respectively given a single panniculus carnosus injection at choke zone II of either 1×10⁵ (BMSCs^low), 1×10⁶ (BMSCs^hig) BMSC, or phosphate-buffered saline (PBS). On postoperative day seven, we assessed the gross view of the flap and survival. We also evaluated microvessels by histological examination and angiogenesis-related gene expression by quantitative real-time polymerase chain reaction. After high dosage of BMSC, the flap survival rate, diameter and density of microvessels, vascular endothelial growth factor (VEGF) and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) levels were significantly higher in the BMSC treatment group than the control group. We therefore confirmed the positive effects of BMSC on the survival of multi-territory perforator flaps.

Comparison of incisional delay patterns on a rat random flap model

One of the simplest form of surgical delay can be performed by placing an incision around the flap without undermining, prior to flap elevation. In this study, we have compared the efficiency of different patterns of skin incision to improve flap survival. Twenty-eight animals were used in four groups. Incisional delay was performed prior to flap elevation in the three experiment groups. Complete incision of the three flap edges was performed in the all experiment groups with the exception of an intact skin section on the middle 1/3rd of the bilateral edges in group 1 (bilateral skin edge preserved delay: BSEPD), of a unilateral edge in group 2 (unilateral skin edge preserved delay: USEPD) and of the superior edge in group 3 (superior skin edge preserved delay: SSEPD) without any undermining. Two weeks following the delay procedure, dorsal skin flaps were raised and reinserted back to their place. The results were evaluated with the measurement of necrotic flap area, microangiographic imaging and histological evaluation. The mean percentage of necrotic flap area to whole flap area was 16.94%, 7.54%, 23.34% and 50.6% in the BSEPD, USEPD, SSEPD and control groups, respectively. In selected microangiographic images, vessels were more prominent in the delay groups. The results of the study indicate that three sided incision with an intact skin on the superior edge is not effective in providing a sufficient delay and flap survival improvement when compared to incisions with intact skin on the unilateral and bilateral edges.