[Two-stage microsurgical soft tissue reconstruction of a complex sacral wound using an arteriovenous loop]. / Zweizeitige mikrochirurgische Weichteilrekonstruktion einer komplexen sakralen Wunde unter Verwendung eines arteriovenösen Loops.

The surgical reconstruction of sacral soft tissue defects is challenging, and complications are frequent. We report a successful two-stage three-dimensional microsurgical soft tissue reconstruction of a wide and deep sacral defect anastomosing a free combined ALT/TFL/rectus femoris flap to an ipsilateral vena saphena magna arteriovenous loop which was applied primarily. This case shows that complex microsurgical procedures can be promising in this demanding patient population if the indication is correct and the operative/perioperative strategy is clear.

Use of Cold Plasma in Wound Healing: A Case Report.

ABSTRACT: The treatment of chronic wounds remains a serious medical and social problem. There are many innovative therapeutic approaches for the treatment of chronic wounds, one of which is cold plasma therapy. This case report describes an 85-year-old patient who presented with a chronic wound on his lower right leg. Despite repeated surgical wound debridements, his wound did not improve. Therefore, the authors initiated cold plasma therapy for his chronic wound. Through repeated application of cold plasma, the wound was completely healed within 8 weeks. As a noninvasive procedure, the cold plasma treatment was well tolerated and had no adverse effects. This case report provides promising results and could be the basis for further studies to confirm the effectiveness of active wound dressings with cold plasma in the treatment of chronic wounds.

Revisionary soft tissue reconstruction of posterior midline defects after spinal surgery-plastic reconstructive options including perforator flaps.

BACKGROUND: Chronic prevertebral soft tissue defects with exposed metal hardware following spinal surgery represent a challenging complication. Frequently patients underwent multiple previous operations due to wound complications. Surrounding soft tissues are often compromised due to malperfusion, severe subcutaneous scarring, previous local advancement flaps and therefore impair stable wound closure. METHODS: Patients after spinal surgery who received complex soft tissue reconstructions between 2011 and 2015 were analyzed retrospectively. Patient`s age, risk factors, wound size, cause and defect location as well as complication rates were evaluated. A focus was set on therapeutic strategies and decision-making concerning reconstructive techniques. RESULTS: Fourteen patients receiving 27 pedicled and one free flap were included in the study. Patients mean age was 51.1 years, mean wound size was 144 cm2. Defects were located in the lumbar spine [8], cervical spine [2] and thoracic spine [1], respectively. Three patients suffered from extensive defects affecting more than one area. Mean time of flap surgery was 213 minutes. Fifteen perforator-based flaps and 11 non-perforator (classic rotation-flaps), 1 pedicled and 1 free latissimus dorsi flap were used. In 9 patients (64.3%) different flaps had to be combined in a single-staged procedure due to large wounds. Implant material was removed completely in six patients (42.9%), whereas in five patients (35.7%) implants were replaced within the operation for soft tissue reconstruction. In three patients (21.4%) initial implant removal or replacement was not possible which leads to prolonged postoperative wound infections. CONCLUSIONS: Most patients with exposed spinal hardware suffered from multiple comorbidities and showed a poor general condition. Due to the reduced soft tissue quality wound healing is significantly impaired. Exposed implant material should be replaced or removed when possible. Therefore, the complete armamentarium of plastic reconstructive techniques is required for wound closure. Today, perforator flaps play a prominent role due to the variability, excellent vascularization and sufficient subcutaneous filling capacities.

Perforator-Based Flaps for Defect Reconstruction of the Posterior Trunk.

INTRODUCTION: Full-thickness soft tissue defects of the back remain challenging clinical problems for reconstructive surgeons. Among a vast variety of local flap options, perforator-based local flaps gain increasing popularity lately. Because mostly heterogeneous patient cohort comparison of different perforator flaps is difficult and decision-making algorithms are lacking. METHODS: Patients, who received a local perforator-based soft tissue reconstruction between 2012 and 2019, were evaluated retrospectively. Patients' data were evaluated in terms of flap type and dimension, wound size and cause, surgery time, postoperative complications, and hospitalization. A focus was set on decision making concerning reconstructive techniques and flap choice for defect closure. RESULTS: Thirty-six patients (17 women, 19 men) were included, who received 40 perforator-based local flaps to reconstruct extended defects of the posterior trunk. Mean patient age was 56.3 years and mean hospitalization was 29 days. Average time of flap surgery was 179.7 minutes. Mean flap size was 160.8 cm and average defect size was 110 cm. Defects occurred because of tumor resection (50%), orthopedic/trauma surgery (16.7%), or pressure sores (33.3%). Twenty-eight propeller flaps (PPFs, 70%) and 12 perforator-based VY-advancement flaps (P-VYF, 30%) were transferred. In 4 patients, a bilateral approach using more than one flap was necessary. Revision surgery was required in 9 patients (25%) because of postoperative hematoma (n = 3), postoperative wound infection (n = 3), partial flap necrosis (1× P-VYF) and 2 flap losses (2× PPFs). CONCLUSIONS: Pedicled perforator flaps are a reliable option for soft tissue reconstruction of complex wounds of the posterior trunk. A flexible surgical strategy is mandatory, and the individual perforator anatomy has to be considered. In most cases, P-VYFs or PPFs are reliably possible and allow sufficient defect reconstruction. However, skin incisions should always be performed in a way that classic random pattern flaps are still possible. Even in large defects combined, local perforator flaps may lead to sustainable soft tissue reconstructions without functional donor site deficits.

Enzymatic debridement for the treatment of severely burned upper extremities - early single center experiences.

BACKGROUND: Severe burns of hands and arms are complex and challenging injuries. The Standard of care (SOC) - necrosectomy with skin grafting - is often associated with poor functional or aesthetic outcome. Enzymatic debridement (ED) is considered one promising alternative but, until recently, results proved to be highly variable. METHODS: Between 04/2014 and 04/2015, 16 patients with deep partial- to full-thickness burns of the upper extremities underwent enzymatic debridement (ED) in our Burn Center and were evaluated for extent of additional surgery, wound healing, pain management and functional parameters. RESULTS: Following ED, no further surgical intervention was required in 53.8 % of the study population. In patients who required surgical treatment, the the skin-grafted area could be reduced by 37.0 % when compared to initial assessment. Time from injury to ED was 24.4 h and patients were able to start physical therapy after 2.0 days but suffered from prolonged wound closure (28.0 days). Regionally administered anesthesia proved to be superior to pain medication alone as pain levels and consumed morphine-equivalent were lower. Post-demission follow-up showed good functional results and pain levels with low scores in two self-report questionnaires (DASH, PRWE-G) but 3 patients reported increased susceptibility to shear stress. Based on these early experiences, we developed a 3-step algorithm for consecutive patients allowing appropriate and individualized treatment selection. CONCLUSIONS: We see a potential benefit for ED in the treatment of severely burned hands and forearms but further investigations and proper prospective, randomized controlled trials are needed to statistically support any outlined assumptions.

Influences of Macrohemodynamic Conditions on Systemic Microhemodynamic Changes in Burns.

PURPOSE: The clinical course after major burns is characterized by microcirculatory changes and consecutive capillary leakage. However, current clinical monitoring does not properly assess microcirculation, whereas macrohemodynamic changes are continuously evaluated. Here, we assess if macrohemodynamic and microhemodynamic parameters after burn trauma are correlated in a rat model. METHODS: Burn plasma harvested from donor rats 4 hours after thermal injury (30% total body surface area, 100 °C water, 12 seconds) was administered intravenously to healthy animals during 2 hours of intravital microscopy (burn group [BG]). Shamburn plasma (same procedure but water at 37°C) was transferred for negative controls (shamburn group [SBG]). Intravital microscopy was performed at 0, 60, and 120 minutes to assess capillary leakage measuring fluorescein isothiocyanate-albumin extravasation. Macrocirculation was assessed using mean arterial pressure and heart rate, whereas microcirculation was evaluated using red blood cell velocity, venular diameter, venular wall shear rate and plasma extravasation at 0, 60, and 120 minutes in postcapillary venules. RESULTS: Thirty mesenteric venules (16 animals) in SBG and 31 mesenteric venules (15 animals) in BG were observed during intravital microscopy. Mean arterial pressure and heart rate remained within acceptable margins and showed no significant differences, neither within nor between groups. Significant correlations between macrohemodynamic and microhemodynamic conditions were neither observed for BG nor SBG, except from a significant correlation of MAP and plasma extravasation at T60. However, at T120 mesenteric venules in the BG clearly showed microvascular burn edema, whereas venules in SBG did not. CONCLUSIONS: Stabilization of macrohemodynamic conditions may not necessarily have positive effects on microcirculatory derangements-a fact that has not been shown for burns yet, that is-however, well described for sepsis. Further studies are required to show whether distinct monitoring of microcirculation may offer new approaches for burn trauma treatment.

Influence of Cdp-Choline Administration on Early Burn Edema in Rats.

PURPOSE: The cholinergic anti-inflammatory pathway may play an important role in early burn edema. Therefore, we evaluated the influence of cdp-choline on early systemic burn edema and leukocyte activation in shock in rat mesenteries after burn plasma transfer. METHODS: Burn plasma harvested from donor rats 4 hours after thermal injury (30% total body surface area, 100°C water, 12 seconds) was administered intravenously to healthy animals during 2 hours of intravital microscopy. Shamburn plasma (same procedure but water at 37°C) was transferred for negative controls. In the study group, bolus injection of 100 mg/kg body weight cdp-choline was undertaken 15 minutes before examination. Intravital microscopy was performed in the ileal portion of rat mesenteries at 0, 60, and 120 minutes. Capillary leakage was assessed by fluorescein isothiocyanate-albumin extravasation and leukocyte-endothelial interaction were observed via transillumination microscopy. To assure comparable hemodynamic conditions, microhemodynamic parameters, foremost venular wall shear rate, were assessed. RESULTS: Capillary leakage increased significantly after burn plasma transfer when compared to the shamburn group. Additional intravenous administration of cdp-choline attenuates macromolecular efflux to shamburn levels. Leukocyte activation is reduced after cdp-choline treatment. CONCLUSIONS: The significant increase of albumin efflux in rat mesenteries after burn plasma transfer is decreased by additional cdp-choline bolus administration. Further investigations for proof of the relevance of the cholinergic anti-inflammatory pathway in early burn trauma are strongly required.

Cytidine-5-diphosphocholine reduces microvascular permeability during experimental endotoxemia.

BACKGROUND: Microvascular permeability and leukocyte adhesion are pivotal mechanisms in sepsis pathophysiology contributing to the development of shock and mortality. No effective pharmacological therapy is currently available to restore microvascular barrier function in sepsis. Cholinergic mediators have been demonstrated to exert anti-inflammatory effects during inflammation. Cytidine-5-diphosphocholine (CDP-choline) is an extensively studied cholinergic drug due to its brain protective characteristics in cerebrovascular diseases. This study evaluated the effect of CDP-choline on microvascular permeability and leukocyte adhesion during endotoxemia. METHODS: Macromolecular leakage, leukocyte adhesion, and venular wall shear rate were examined in mesenteric postcapillary venules of rats by using intravital microscopy (IVM). Lipopolysaccharide (LPS) (4 mg/kg/h) or equivalent volumes of saline were continuously infused following baseline IVM at 0 min. IVM was repeated after 60 and 120 min in endotoxemic and nonendotoxemic animals. CDP-choline (100 mg/kg) was applied as an i.v. bolus. Animals received either saline alone, CDP-choline alone, CDP-choline 10 min before or 30 min after LPS administration, or LPS alone. Due to nonparametric data distribution, Wilcoxon test and Dunn's multiple comparisons test were used for data analysis. Data were considered statistically significant at p < 0.05. RESULTS: Treatment with LPS alone significantly increased microvascular permeability and leukocyte adhesion and decreased venular wall shear rate. CDP-choline significantly reduced microvascular permeability in animals treated with LPS. Leukocyte adhesion and venular wall shear rate were not affected by CDP-choline during endotoxemia. CONCLUSION: CDP-choline has a protective effect on microvascular barrier function during endotoxemia. Considering the excellent pharmacologic safety profile of CDP-choline, its use could be an approach for the treatment of capillary leakage in sepsis.

Time-dependent effect of clonidine on microvascular permeability during endotoxemia.

BACKGROUND: Endothelial leakage with accompanying tissue edema and increased leukocyte adhesion are characteristics of the vascular inflammatory response. Tissue edema formation is a key mechanism in sepsis pathophysiology contributing to impaired tissue oxygenation and the development of shock. Sepsis mortality is directly associated with the severity of these microcirculatory alterations. Dysfunction of the sympathetic nervous system can have deleterious effects in generalized inflammation. This study evaluated the effect of the adrenergic alpha 2 agonist clonidine on microvascular permeability and leukocyte adhesion during endotoxemia. METHODS: Macromolecular leakage, leukocyte adhesion, and venular wall shear rate were examined in mesenteric postcapillary venules of rats by using intravital microscopy (IVM). Lipopolysaccharide (LPS) (4mg/kg/h) or equivalent volumes of saline were continuously infused following baseline IVM at 0min. IVM was repeated after 60 and 120min in endotoxemic and nonendotoxemic animals. Clonidine (10µg/kg) was applied as an i.v. bolus. Animals received either (i) saline alone, (ii) clonidine alone, (iii) clonidine 45min prior to LPS, (iv) clonidine 10min prior to LPS, (v) clonidine 30min after LPS, or (vi) LPS alone. Due to nonparametric data distribution, Wilcoxon test and Dunn's multiple comparisons test were used for data analysis. Data were considered statistically significant at p<0.05. RESULTS: LPS significantly increased microvascular permeability and leukocyte adhesion and decreased venular wall shear rate. Clonidine significantly reduced microvascular permeability when applied 45min before or 30min after LPS administration. Leukocyte adhesion and venular wall shear rate were not affected by clonidine during endotoxemia. CONCLUSION: Clonidine reduces microvascular permeability in endotoxemic animals in a time-dependent manner. Adrenergic alpha 2 agonists might prove beneficial in stabilizing capillary leakage during inflammation.

Methysergide attenuates systemic burn edema in rats.

BACKGROUND: Thermal injuries of more than 20% total body surface area result in systemic shock with generalized edema. Burn shock is induced by a variety of mediators, mainly immunomodulative cytokines. Administration of methysergide (Met), a serotoninergic receptor blocking agent, reduces generalized edema in endotoxemia in rats. In this study we evaluated the systemic effects of Met after thermal injury. METHODS: Donor rats (DR [n=8]) for positive controls and study groups underwent thermal injury (100°C water, 30% TBSA (Total Burn Surface Area), 12s). Shamburn plasma was harvested after a shamburn procedure ([n=4], 37°C water, 30% TBSA, 12s). Plasma was harvested 4h posttrauma and was transferred to healthy individuals. Recipient animals were randomized in 3 groups (1: burnplasma, 2: shamburn, 3: burnplasma plus methysergide (Bolus of 1mg/kg body weight)). Intravital microscopy was performed in mesenteric venules (0/60/120min). Edema was assessed by FITC-albumin extravasation. Leukocyte sticking (cells/mm(2)) and microhemodynamic parameters were assessed. RESULTS: Significant systemic capillary leakage was observed after burnplasma-transfer. Edema formation was significantly lower in negative controls. Application of methysergide reduced FITC-efflux to baseline levels. Adherent leukocytes increased in all groups, at 120min the amount of adherent leukocytes in positive controls was significantly higher in comparison to shamburn, differences to MET-groups were not significant. CONCLUSION: Burnplasma transfer to healthy individuals induces leukocyte activation and plasma extravasation and this effect is reduced by administration of Met. This may be attributed to leukocyte dependent as well as independent mechanisms. Evaluation of more specific serotoninergic antagonists is required to distinguish between systemic and local effects.

Cinanserin reduces plasma extravasation after burn plasma transfer in rats.

BACKGROUND: Thermal injuries greater than 20% body surface area (BSA) lead to systemic edema and hypovolemic shock. Capillary leakage is induced by different immunomodulative cytokines. Serotonin (5-HT) plays an important role in inflammation, vasodilatation and vasoconstriction and many other pathways such as systemic inflammation in endotoxemia and burns. Cinanserin, a specific 5-HT2 receptor blocking agent was administered to observe whether burn induced systemic edema can be reduced. METHODS: Donor animals underwent thermal injury (100°C water, 30% BSA, 12s) for positive controls and negative controls underwent a shamburn procedure (37°C water, 30% BSA, 12s). Donor rat-plasma was transferred to healthy individuals after bolus injection of Cinanserin (5mg/kg body weight) was performed in recipient animals. Intravital microscopy was performed in mesenteric venules (0/60/120min) to asses systemic edema by FITC-albumin extravasation. Additionally, leukocyte activation (cells/mm(2)) was observed. RESULTS: Burnplasma-transfer results in systemic capillary leakage that is not observed in sham burn controls. Intraveneous application of Cinanserin significantly reduces systemic burn edema to shamburn levels. Leukocyte-endothelial interactions are significantly reduced by administration of Cinanserin. CONCLUSION: Specific 5-HT2 antagonism reduces systemic burn edema and leukocyte activation after plasma transfer. Reduction of capillary leakage may be partially mediated by leukocyte dependent as well as independent mechanisms. Future studies need to evaluate specific 5-HT2 receptor subtypes to distinguish between local and systemic effects of serotonin antagonists.