[Postoperative monitoring of free muscle flaps using perforator-based adipocutaneous skin paddles: economy, quality of care and aesthetics]. / Postoperatives Monitoring freier Muskellappenplastiken mittels perforatorbasierten adipokutanen Monitorinseln: Ökonomie, Versorgungsqualität und Ästhetik.

INTRODUCTION: Besides fasciocutaneous workhorse flaps, free muscle flaps for the reconstruction of large soft tissue defects are well-established standard microsurgical procedures. Random-pattern adipocutaneous skin paddles are often included for postoperative perfusion monitoring of the muscle flap. At our institution, both conventional broad-based and perforator-based adipocutaneous skin paddles are used. While conventional skin paddles have to be removed during a second operation, perforator-based skin paddles can be removed at the bedside by ligature. The present study aims to compare economic aspects, quality of care and aesthetic results of perforator-based versus conventional adipocutaneous skin paddles after free muscle flap transfer. METHODS: 102 patients treated between August 2014 and July 2016 were identified and included in a retrospective data analysis. Patients with perforator-based skin paddles (group A) were compared with a population of patients with conventional skin paddles (group B). Patient characteristics, procedural characteristics, economic data and aesthetic results were compared between both groups. RESULTS: Perforator-based skin paddles were raised in 72 patients (group A, 71 %), and conventional skin paddles were raised in the remaining 30 patients (group B, 29 %). Patient, defect, and flap characteristics were comparable in both groups. Operating times tended to be shorter in group B. Skin paddle removal was performed significantly earlier in group A (p < 0.01). Both overall and post-reconstructive length of hospital stay were significantly shorter in group A (p = 0.03; p < 0.01). Also, personnel and material resources were saved and more satisfactory aesthetic results were achieved in group A. CONCLUSION: Perforator-based monitor islands can help avoid secondary operations that would otherwise be necessary to remove monitoring skin paddles. Thus, the inpatient length of stay can be reduced while sparing material and human resources.

The Free Myocutaneous Tensor Fasciae Latae Flap-A Workhorse Flap for Sternal Defect Reconstruction: A Single-Center Experience.

INTRODUCTION: Deep sternal wound infections (DSWI) after cardiac surgery pose a significant challenge in reconstructive surgery. In this context, free flaps represent well-established options. The objective of this study was to investigate the clinical outcome after free myocutaneous tensor fasciae latae (TFL) flap reconstruction of sternal defects, with a special focus on surgical complications and donor-site morbidity. METHODS: A retrospective chart review focused on patient demographics, operative details, and postoperative complications. Follow-up reexaminations included assessments of the range of motion and muscle strength at the donor-site. Patients completed the Quality of Life 36-item Short Form Health Survey (SF-36) as well as the Lower Extremity Functional Scale (LEFS) questionnaire and evaluated aesthetic and functional outcomes on a 6-point Likert scale. The Vancouver Scar Scale (VSS) and the Patient and Observer Scar Assessment Scales (POSAS) were used to rate scar appearance. RESULTS: A total of 46 patients (mean age: 67 ± 11 years) underwent sternal defect reconstruction with free TFL flaps between January 2010 and March 2021. The mean defect size was 194 ± 43 cm2. The mean operation time was 387 ± 120 min with a flap ischemia time of 63 ± 16 min. Acute microvascular complications due to flap pedicle thromboses occurred in three patients (7%). All flaps could be salvaged without complete flap loss. Partial flap loss of the distal TFL portion was observed in three patients (7%). All three patients required additional reconstruction with pedicled or local flaps. Upon follow-up, the range of motion (hip joint extension/flexion (p = 0.73), abduction/adduction (p = 0.29), and internal/external rotation (p = 0.07)) and muscle strength at the donor-sites did not differ from the contralateral sides (p = 0.25). Patient assessments of aesthetic and functional outcomes, as well as the median SF-36 (physical component summary (44, range of 33 to 57)) and LEFS (54, range if 35 to 65), showed good results with respect to patient comorbidities. The median VSS (3, range of 2 to 7) and POSAS (24, range of 18 to 34) showed satisfactory scar quality and scar appearance. CONCLUSION: The free TFL flap is a reliable, effective, and, therefore, valuable option for the reconstruction of extensive sternal defects in critically ill patients suffering from DSWIs. In addition, the TFL flap shows satisfactory functional and aesthetic results at the donor-site.

[Immunosuppressive effect of mitomycin C-treated peripheral mononuclear blood cells (MICs) in vascularised composite allotransplantation]. / Immunsuppressive Wirkung von Mitomycin-C-behandelten mononukleären Zellen des peripheren Blutes (MICs) in der Vaskularisierten Composite Allotransplantation.

BACKGROUND: Vascularized Composite Allotransplantation (VCA) enables the restoration of complex tissue defects. Since the first successful hand and face transplants were performed, clinical and experimental research has consistently improved immunosuppressive therapies. The incubation of peripheral blood mononuclear cells (PBMCs) with mitomycin C (MMC) results in immunomodulatory cells (MICs). In previous studies, the systemic application of MICs on the day of allogeneic hind limb transplantation led to a significant immunosuppression in rats. The aim of this study is to further investigate the optimal point in time of MIC application in a complex VCA model. MATERIAL AND METHODS: In six groups, 60 allogeneic hind limb transplantations were performed. Fully mismatched rats were used as hind limb donors [Lewis (LEW)] and recipients [Brown-Norway (BN)]. Group A received donor-derived MICs seven days preoperatively. Group B received no immunosuppression; group C received untreated PBMCs seven days prior to transplantation. Animals in group D received cell culture media, whereas group E was treated with a standard immunosuppression consisting of tacrolimus and prednisolone. In group F, syngeneic hind limb transplantations (BN→BN) were performed. Transplant rejection was assessed clinically and histologically. RESULTS: Group A showed a significantly earlier onset of allograft rejection after 3.5 ± 0.2 days (p < 0.01) when compared with control groups B, C and D (5.5 ± 0.7, 5.3 ± 0.7 und 5.7 ± 0.5). Groups E and F showedno allograft rejection. CONCLUSION: This study shows that the time of application determines the immunomodulatory effects of MICs. Whereas the systemic application of MICs on the day of transplantation led to a significant immunosuppression in previous studies, this study demonstrates that preoperative injections of MICs lead to an acceleration of allotransplant rejection. Follow-up studies are necessary to investigate further modifications of application time as well as dose-effect relations and cell characteristics of these potential immunosuppressive cells.

Safety, Pharmacodynamics, and Efficacy of High- Versus Low-Dose Ascorbic Acid in Severely Burned Adults.

In sepsis and burns, ascorbic acid (AA) is hypothesized advantageous during volume resuscitation. There is uncertainty regarding its safety and dosing. This study evaluated high dose AA (HDAA: 66 mg/kg/h for 24 hours) versus low dose AA (LDAA: 3.5 g/days) administration during the first 24 hours in severely burned adults. We conducted a retrospective study comparing fluid administration before and after switching from low dose to HDAA in severely burned adults. A total of 38 adults with burns >20% TBSA, who received either HDAA or LDAA were included in this retrospective study. AA serum concentrations were quantified at 0, 24, and 72 hours postburn. HDAA impact on hemodynamics, acid-base homeostasis, acute kidney injury, vasopressor use, resuscitation fluid requirement, urinary output, and the incidence of adverse effects was evaluated; secondary clinical outcomes were analyzed. AA plasma levels were 10-fold elevated in the LDAA and 150-fold elevated in the HDAA group at 24 hours and decreased in both groups afterwards. HDAA was not associated with a significantly increased risk of any complications. A significant reduction in colloid fluid requirements was noted (LDAA: 947 ± 1722 ml/24 hours vs HDAA: 278 ± 667 ml/24 hours, P = 0.029). Other hemodynamic and resuscitation measures, as well as secondary clinical outcomes were comparable between groups. HDAA was associated with higher AA levels and lower volumes of colloids in adults with severe burns. The rate of adverse events was not significantly higher in patients treated with HDAA. Future studies should consider prolonged administration of AA.

The combination of mitomycin-induced blood cells with a temporary treatment of ciclosporin A prolongs allograft survival in vascularized composite allotransplantation.

BACKGROUND: Vascularized composite allotransplantation (VCA) is a rapidly expanding field of transplantation and provides a potential treatment for complex tissue defects. Peripheral blood mononuclear cells (PBMCs) shortly incubated with the antibiotic and chemotherapeutic agent mitomycin C (MMC) can suppress allogeneic T cell response and control allograft rejection in various organ transplantation models. MMC-incubated PBMCs (MICs) are currently being tested in a phase I clinical trial in kidney transplant patients. Previous studies with MICs in a complex VCA model showed the immunomodulatory potential of these cells. The aim of this study is to optimize and evaluate the use of MICs in combination with a standard immunosuppressive drug in VCA. METHODS: Fully mismatched rats were used as hind limb donors [Lewis (RT11)] and recipients [Brown-Norway (RT1n)]. Sixty allogeneic hind limb transplantations were performed in six groups. Group A received donor-derived MICs combined with a temporary ciclosporin A (CsA) treatment. Group B received MICs in combination with a temporarily administered reduced dose of CsA. Group C served as a control and received a standard CsA dose temporarily without an additional administration of MICs, whereas Group D was solely medicated with a reduced CsA dose. Group E received no immunosuppressive therapy, neither CsA nor MICs. Group F was given a continuous standard immunosuppressive regimen consisting of CsA and prednisolone. The endpoint of the study was the onset of allograft rejection which was assessed clinically and histologically. RESULTS: In group A and B, the rejection-free interval of the allograft was significantly prolonged to an average of 23.1 ± 1.7 and 24.7 ± 1.8 days compared to the corresponding control groups (p < 0.01). Rejection in groups C, D, and E was noted after 14.3 ± 1.1, 7.8 ± 0.7, and 6.9 ± 0.6 days. No rejection occurred in control group F during the follow-up period of 100 days. No adverse events have been noted. CONCLUSION: The findings of this study show that the combination of MICs with a temporary CsA treatment significantly prolongs the rejection-free interval in a complex VCA model. The combination of MICs with CsA showed no adverse events such as graft-versus-host disease. MICs, which are generated by a simple and reliable in vitro technique, represent a potential therapeutic tool for prolonging allograft survival through immunomodulation.

Local administration of Mitomycin-C-Treated peripheral blood mononuclear cells (PBMCs) prolongs allograft survival in vascularized composite allotransplantation.

BACKGROUND: VCA offers a potential treatment for extensive tissue defects. First results of systemic administration of Mitomycin C-treated PBMCs in VCA demonstrated a significant prolongation of allograft survival. The aim of this study is to evaluate if local administration of MMC-PBMCs prolongs allograft survival in allogeneic hind limb transplantations of the rat. METHODS: Sixty allogeneic hind limb transplantations in the rat were performed in six groups. Lewis rats (LEW) were used as hind limb donors and Brown-Norway rats (BN) as recipients. Animals in group A received donor-derived MMC-treated PBMCs locally (i.m.). Group B received no immunosuppressive therapy, group C received a standard immunosuppressive regime consisting of FK506 and Prednisolon, group D (BN to BN) comprised isograft transplantations without immunosuppressive treatment, group E received non-treated PBMCs (i.m.) and group F received phosphate buffered saline (PBS) without cells. The transplanted hind limbs were assessed for color, edema, skin, hair condition, and consistency of the thigh every 8 hours. RESULTS: Rejection in group A was delayed to an average of 7.2 ± 0.6 days. Survival times were significantly prolonged (P < 0.01) compared to control groups B, E, and F (5.5 ± 0.7, 5.8 ± 0.7, and 5.7 ± 0.5 days). Control groups C and D showed no signs of rejection. CONCLUSION: The findings of this study show that local administration of MMC-PBMCs has no side effects and significantly extends allograft survival. Further experiments with MMC-PBMCs treatments repeated at different time-points and being added to low dose immunosuppressive protocols need to be performed to improve experimental and eventually clinical outcome after VCA. © 2015 Wiley Periodicals, Inc. Microsurgery 36:417-425, 2016.

Domestic bioethanol-fireplaces--a new source of severe burn accidents.

BACKGROUND: Bioethanol-fueled fireplaces are popular interior home decoration accessories. Although their safety is promoted frequently, actual presentations of severe burn injuries in our burn intensive care unit (ICU) have focused the authors on safety problems with these devices. In this article we want to explore the mechanisms for these accidents and state our experiences with this increasingly relevant risk for severe burn injuries. MATERIALS AND METHODS: The computerized medical records of all burn intensive care patients in our burn unit between 2000 and 2014 were studied. Since 2010, 12 patients with bioethanol associated burn injuries were identified. Their data was compared to the values of all patients, except the ones injured by bioethanol fireplaces that presented themselves to our burn ICU between the years 2010 and 2014. RESULTS: At time of admission the bioethanol patients had a mean ABSI-score of 4.8 (+/- 2.2 standard deviation (SD)). A mean of 17 percent (+/- 9.1 SD) body surface area was burned. Involvement of face and hands was very common. An operative treatment was needed in 8 cases. A median of 20 days of hospitalization (range 3-121) and a median of 4.5 days on the ICU (range 1-64) were necessary. No patient died. In most cases the injuries happened while refilling or while starting the fire, even though safety instructions were followed. In the control group, consisting of 748 patients, the mean ABSI-score was 5.6 (+/- 2.7 SD). A mean of 16.5 percent (+/- 10.1 SD) body surface area was burned. Treatment required a median of 3 days on the burn ICU (range 1-120). Regarding these parameters, the burden of disease was comparable in both groups. CONCLUSION: Bioethanol-fueled fireplaces for interior home decoration are a potential source for severe burn accidents even by intended use.

Mitomycin-C-treated peripheral blood mononuclear cells (PBMCs) prolong allograft survival in composite tissue allotransplantation.

BACKGROUND: Composite tissue allotransplantation (CTA) was introduced as a potential treatment for complex reconstructive procedures and has become a clinical reality. Hand and face transplantation, the most widely recognized forms of CTA, have intensified immunological research in this emerging field of transplantation. Mitomycin C (MMC) is an alkylating agent that suppresses allogeneic T-cell responses. MMC-treated dendritic cells/PBMCs have been shown to induce donor-specific tolerance in solid organ allograft transplantations. METHODS: Fully mismatched rats were used as hind limb donors [Lewis (RT1(1))] and recipients [Brown-Norway (RT1(n))]. Fifty-five allogeneic hind limb transplantations were accomplished in six groups. Group A (n = 10) received donor-derived MMC-treated PBMCs on transplantation day. Group B (n = 10) rats received no immunosuppression, group C (n = 10) received FK506 and prednisolon, group D consisted in isograft transplantation without immunosuppression, group E (n = 10) received non-treated PBMCs, and group F (n = 5) received PBS without any donor-derived cells. Rejection was assessed clinically and histologically. RESULTS: In group A, the survival times of the allografts were prolonged to an average of 8.0 d. Rejection was significantly delayed compared with the averages of the corresponding control groups B, E, and F (5.5, 5.9, and 5.8 d). No rejection was seen in control groups C and D. CONCLUSION: These results demonstrate that MMC-treated donor PBMCs significantly prolong allograft survival when administered systemically on the day of transplantation. However, the immunomodulatory effect is relatively modest with further research being required to clarify dose-effect relations, cell characteristics, and an optimized mechanism and timing for cell application.

Shock wave treatment in composite tissue allotransplantation.

INTRODUCTION: Composite tissue allotransplantation is a newly emerged field of transplantation. Shock wave technology has already been used in the treatment of urologic and orthopedic disorders. Recent studies demonstrated a suppression of the early proinflammatory immune response. METHODS: 50 allogeneic hindlimb transplantations were performed on rats in 5 different groups. Group A (n = 10), (Lewis → Brown-Norway) received 500 impulses of extracorporeal shock wave. Groups B, C, D, and E served as control groups with group B (n = 10) receiving no immunosuppression, group C (n = 10) receiving FK506 and prednisolone, group D (n = 10) receiving no immunosuppression with isograft transplantations (Brown-Norway → Brown-Norway) and group E receiving 500 impulses of extracorporeal shock wave on the contralateral hindlimb. RESULTS: Rejection of the allogeneic hindlimb occurred on average 7.12 days after transplantation in group A (extracorporeal shock wave). Rejection was significantly delayed compared to the control groups B (no immunosuppression) and E (contralateral hindlimb), where rejection of the allogeneic hindlimb occurred on average 5.49 and 5.6 days after transplantation (t test, P < .01). No rejection was seen in groups C and D. CONCLUSIONS: For the first time, shock waves have been applied in a composite tissue allotransplantation model and resulted in a significant immunosuppressive effect. These promising first results have showed that shock wave treatment is clinically relevant in composite tissue allotransplantation and justify subsequent research to improve the experimental and clinical outcome.

Single-stage Matriderm® and skin grafting as an alternative reconstruction in high-voltage injuries.

This article presents a retrospective analysis of a series of nine patients requiring reconstruction of exposed bone, tendons or joint capsules as a result of acute high-voltage injuries in a single burn centre. As an alternative to free tissue transfer, the dermal substitute Matriderm(®) was used in a one-stage procedure in combination with split-thickness skin grafts (STSG) for reconstruction. Nine patients, in the period between 2005 and 2009 with extensive high-voltage injuries to one or more extremities which required coverage of exposed functional structures as bone, tendons or joint capsule, were included. A total of 11 skin graftings and 2 local flaps were performed. Data including regrafting rate, complications, hospital stays, length of rehabilitation and time until return to work were collected. Eleven STSG in combination with Matriderm(®) were performed on nine patients (success rate 89%). One patient died. One patient needed a free-flap coverage as a secondary procedure. The median follow-up was 30 months (range 6-48 months). The clinical results of these nine treated patients concerning skin-quality and coverage of exposed tendons or joint capsule were very good. In high-voltage injuries free-flap failure occurs between 10% and 30% if performed within the first 4-6 weeks after trauma. The use of single-stage Matriderm(®) and skin grafting for immediate coverage described in this article is a reliable alternative to selected cases within this period.

Necrotizing fasciitis of the extremities: 34 cases at a single centre over the past 5 years.

BACKGROUND: Worldwide the incidence of necrotizing fasciitis (NF) is on the rise. This rapidly progressive infection is a true infectious disease emergency due to its high morbidity and mortality. The mainstay of therapy is prompt surgical debridement, intravenous antibiotics, and supportive care with fluid and electrolyte management. Because of its high mortality rate, patients are increasingly referred to burn centres for specialized wound and critical care issues. METHODS: A retrospective chart review was performed of 34 consecutive patients over a 5-year period with NF of the upper and/or lower extremities that required surgical debridement and reconstruction. RESULTS: The overall survival rate was 96%, with an average length of hospital stay of 64.0 ± 5.5 days. The time until the first operation was 1.3 days. The average age of the patients was 56.7 ± 10.6 years. The patients averaged 1.6 relevant comorbidities. One patient who had five comorbidities died. The affected total body surface (TBS) averaged 8.2 ± 2.1%. CONCLUSION: Early recognition and treatment remain the most important factors influencing survival in NF. Yet, early diagnosis of the condition is difficult due to its similarities with other soft-tissue disorders. Repeated surgical debridement and incisional drainage continues to be essential for the survival. However, these infections continue to be a source of high morbidity, mortality and significant healthcare resource consumption. These challenging patients are best served with prompt diagnosis, immediate radical surgical debridement and aggressive critical care management. Referral to a major burn centre may help to provide optimal surgical intervention, wound care and critical care management.