Background In 2001, the first combined kidney with skin transplantation was performed in humans. Due to high immunogenicity of the skin graft, it may serve as a sentinel flap for simultaneously transplanted organs, potentially enabling a more precise prediction of organ rejection. To create a reproducible investigative method a novel rat model for simultaneous vascularized composite allotransplantation (VCA) and solid organ transplantation (SOT) was developed. Methods Left kidneys from male Dark Agouti rats (DA, RT1, n = 22) were removed and orthotopically transplanted to Lewis rats (LEW, RT1, n = 22). In addition, a vascularized full thickness hemi abdominal wall flap was transplanted as a sentinel flap. No systemic immunosuppression was administered postoperatively. Surgical steps and times were analyzed, and tissue samples were examined for ischemia-reperfusion injury, apoptosis and early signs of rejection. Results Donor surgery took on average 122 minutes ( 30 minutes). Recipient operation required 298 minutes ( 24 minutes). Histological evaluation showed no signs of rejection in the abdominal wall transplant (AWTX) 120 min after transplantation and 60 min in kidney transplants. An increase in ischemic damage with apoptotic cells and formation of tubular casts was detected in renal transplants. Conclusion To generate quantitative data for the benefit of SOT with VCA, an animal model of combined kidney and vascularized abdominal wall transplantation was created. Immediate postoperative histoevaluation showed evidence of ischemia-reperfusion injury and elevation of apoptosis. Further work will compare different endpoints and evaluate whether rejection episodes could be detected by utilizing a VCA sentinel flap.

Background: Venous congestion remains a major threat to deep inferior epigastric perforator (DIEP) flap survival. While superdrainage via the superficial inferior epigastric vein (SIEV) is an established strategy, few reports describe temporary controlled drainage as a salvage option when a second venous anastomosis is not feasible. Methods: We present two cases of bilateral DIEP flap breast reconstruction complicated by early venous congestion due to superficial venous dominance. In each, a trimmed angiocatheter was inserted into the SIEV and secured to allow controlled venous outflow. Drainage was titrated based on clinical findings and perfusion monitoring, and catheters were weaned and removed once congestion resolved. Results: In Case 1, congestion was identified intraoperatively and managed with intermittent drainage every 30 minutes, later spaced and discontinued by postoperative day (POD) 2. The catheter was removed on POD 3, and both flaps survived without fat necrosis. In Case 2, congestion was detected postoperatively with declining tissue oximetry readings. Controlled drainage improved perfusion, and the catheter was removed on POD 3. The patient experienced delayed wound healing and a small focus of fat necrosis excised at revision, but flap viability was preserved. Conclusion: Controlled drainage using a trimmed angiocatheter provides a simple, reproducible option to augment venous outflow in DIEP flaps with superficial dominance. This minimally invasive approach may serve as an alternative to formal superdrainage, enabling flap salvage while avoiding additional anastomoses or prolonged operative time.

Abstract Following its initial description in 1994, the deep inferior epigastric perforator (DIEP) flap has become the gold standard in autologous breast reconstruction. While sequential modifications have improved patient outcomes, functional donor site morbidity, abdominal bulge, and hernia remain a challenge. Techniques such as robotic surgery show promise in mitigating these issues but are limited by the need for specialized equipment and training. The Paramedian Reflection for Innervated Muscle Enhancement (PRIME) DIEP flap is a novel technique that preserves innervated rectus muscle and minimizes fascial disruption without requiring robotic assistance for flap harvest. Patient selection is based on preoperative imaging, identifying a suitable dominant medial row perforator(s) with a short intramuscular course. A limited fascial incision over the perforator, followed by a paramedian fascial extension, medial reflection of the rectus abdominis, and submuscular pedicle dissection, allows for safe visualization while minimizing abdominal wall morbidity. Between June 2023 and February 2025, 15 patients underwent 18 PRIME DIEP flaps. All flaps survived, with one patient requiring reoperation for hematoma. There were no flap losses, readmissions, or donor site complications, such as bulge or hernia, at 30-day follow-up. About 72.2% of flaps were based on a single perforator, with an average flap weight of 631.7 g. The PRIME DIEP flap represents the next evolution in autologous breast reconstruction by offering a reproducible, muscle- and nerve-sparing technique, enhancing abdominal wall function in suitable patients. This technical modification also allows for the incorporation of the fascial closure in a midline plication, which may improve vascularity of the fascia following DIEP flap harvest. Further prospective studies are underway to evaluate the impact on long-term functional outcomes and further refine patient selection criteria.

Abstract This technical note presents an innovative technique that uses tissue paper to create three-dimensional (3D) models to visualize tissue defects. This approach allows the construction of detailed, anatomically accurate models that significantly enhance surgeons' and medical professionals' comprehension of tissue damage in various clinical scenarios.The key aspects of this technique include assessing the location and size of the defect, selecting an appropriate donor site, and designing the flap using tissue paper at the recipient site before refining it to match the donor site. Different flap designs, such as local, regional, and free flaps, are used, each offering distinct advantages and limitations depending on the clinical context.This technique is straightforward, cost-effective, and highly adaptable, making it an invaluable tool for both preoperative planning and educational purposes. Meticulous attention to detail is essential for flap design because it directly influences the success of the procedure. Critical factors, such as tissue laxity, scar orientation, and aesthetic subunits, must be carefully considered to ensure optimal wound healing and cosmetic outcomes.In summary, the use of tissue paper to create 3D models is a valuable technique that enhances the understanding and planning of surgical interventions for tissue defects, ultimately improving clinical outcomes.

Abstract Patients undergoing free flap reconstruction of the lower extremity are typically started on a postoperative dangling protocol. This protocol gradually exposes the free flap to increasing gravitational forces. This study aimed to quantify the internal blood gaseous changes within the free flap over the course of a dangling protocol.Three patients who underwent lower leg free flap reconstruction were included. Capillary blood gas samples were taken daily for six consecutive days (postoperative days 7–12) from the free flap before and after dangling, as well as from the contralateral, “healthy” leg. Mean blood gas curves were created for partial pressure of oxygen (pO2), partial pressure of carbon dioxide (pCO2), and potential hydrogen (pH) levels. A paired t-test was used to compare mean blood gas values.Baseline mean pO2 was decreased (p = 0.002), pCO2 was increased (p < 0.001), and pH levels were lowered (p = 0.021) at the site of the free flap, compared with the contralateral, “healthy” leg. Mean pre- and post-dangling pO2 levels were not significantly different (p = 0.380). Mean pCO2 levels significantly increased after dangling (p = 0.028). Over the course of the dangling protocol, mean pO2, pCO2, and pH curves remained considerably stable.Blood samples taken from the free flap show that the mean pO2 and pH levels are lower, and pCO2 levels are higher compared with the contralateral, “healthy” leg. Furthermore, an increase in dangling duration does not cause significant changes in blood gas values. This raises the question of whether the current form of the dangling protocol accomplishes its intended goal of gradually challenging the flap.

Abstract Background The cross-bridge free flap technique has been described for salvage of cases of traumatic lower limb defects when adequate recipient vessels in the same limb are lacking. While previous accounts mainly focused on utilizing muscle, myocutaneous, or perforator skin flaps, this study presents a series of cross-bridge free vascularized fibular transfer for reconstruction of traumatic tibial defects with extensive soft tissue loss. Methods The study included 22 cases with an average age at surgery of 24 ± 8 years and an average tibial bone defect of 14.2 ± 3.3 cm. In this technique, the fibula was inset into the tibial defect and vascularization was performed using the posterior tibial artery of the contralateral leg through a radial forearm flap. The two legs were coimmobilized using Hoffmann external fixator and subsequently separated after 6 weeks. Results All flaps survived. Follow-up averaged 44.4 months. Union occurred in all cases within an average of 4.5 ± 1.9 months and Full weight-bearing was achieved at an average of 9.0 ± 2 months. Stress fractures occurred in eight patients (36.3%) after an average of 12 months. Mean graft hypertrophy at the final follow-up was 67.6%. Six patients showed an average limb length discrepancy of 4.2 cm. Two patients required corrective osteotomy, one ankle fusion, and another Achilles tendon lengthening. Functionally, 20 patients were able to walk without crutches. Conclusion The cross-bridge free vascularized fibular graft is a viable option for reconstruction of complex and extensive tibial defects when no other reconstructive options are available.

Abstract Background Microvascular complications, particularly secondary arterial and venous ischemia, pose significant challenges in reconstructive surgery. This study investigates the potential protective effects of ischemic preconditioning on flap survival, anatomopathological alterations, and immunological responses in pedicled axial flaps subjected to secondary ischemia. Methods Adult male Wistar rats underwent arterial or venous ischemia, with and without ischemic preconditioning. Histological assessments, immunohistochemistry studies, and biochemical analyses were conducted to evaluate the impact of ischemic preconditioning on inflammatory processes and tissue damage. Results Ischemic preconditioning demonstrated a statistically significant decrease in histological lesions, with reductions of 56% in arterial and 47% in venous ischemia, mainly associated with a reduction of inflammatory changes and necrosis processes. Immunological analyses revealed a significant reduction in IgM levels induced by venous ischemia, and a consistent decrease in inflammatory cytokines (interleukin-1 and tumor necrosis factor alpha) in both arterial and venous ischemia following preconditioning. Furthermore, F2-isoprostane levels indicated a lower production of oxidative stress markers in preconditioned flaps. Conclusion This study highlights the beneficial impact of ischemic preconditioning on flap viability, providing robust evidence of reduced histological lesions, inflammation, and oxidative stress in both arterial and venous secondary ischemia scenarios. These findings support the potential clinical relevance of incorporating ischemic preconditioning strategies to improve outcomes in microvascular reconstructive surgery.