Sternal Reconstruction with the Omental Flap-Acute and Late Complications, Predictors of Mortality, and Quality of Life.

BACKGROUND: The omental flap is a reliable flap for the coverage of sternal defects. However, little is known about the predictors of mortality and the long-term outcome in such patients. METHODS: We, therefore, performed a retrospective study from 2002 to 2013, including all patients who underwent sternal reconstruction with the omental flap. RESULTS: A total of 50 patients were identified and mean follow-up was 3.8 years. Patient data was collected from the charts and 14 patients were available for telephone interviews. The majority of patients suffered from deep sternal wound infections. There was no complete flap loss and an overall success rate was 96%. In-hospital mortality was 14% and overall survival over follow-up was 50%. Significant predictors of mortality were age > 65, American Society of Anesthesiologists' status, defect size, prolonged ventilation, and the need for tracheotomy. Postoperative quality of life was reduced compared with other cohorts, especially with regard to bodily function. Pain was also a major problem for most patients along with herniation. CONCLUSION: The omental flap is a safe option even in patients with severe comorbidities. However, based on the data in this study, we would recommend the omental flap as a reserve option rather than first-line treatment for sternal defects.

Improvement of local microcirculation through intermittent Negative Pressure Wound Therapy (NPWT).

BACKGROUND: Negative Pressure Wound Therapy (NPWT) is widely used across different kinds of surgical disciplines. A controversial debate was raised by diverging results from studies that were conducted to examine the impact of NPWT on local perfusion. Thus, there is a lack of evidence for one important underlying factors that influences the physiology of wound healing under an applied NPWT-dressing. OBJECTIVE: To investigate the immediate local perfusion changes due to an applied intermittent NPWT protocol. MATERIAL AND METHODS: A NPWT dressing was applied to the antero-lateral thigh of seven healthy volunteers with two probes of both pressure and microcirculatory measuring devices. One of each probe was placed under the NPWT dressing, the other one in close proximity next to it. A protocol consisting of two cycles of 10 min of -125 mmHg pressure, followed by 10 min of 0 mmHg pressure was applied. Measurements of local pressure to the underlying tissue, as well as microcirculatory changes were performed continuously. RESULTS: Applied vacuum caused compressional forces (27.33 mmHg, p < 0.05) towards the underlying tissue. Blood Flow was increased after both suction periods (+52.5%, +108.7%; p < 0.05) and continued increasing until the end of measurements (+145.3%). This was accompanied by significant increase in Oxygen Saturation (+21.6%; p < 0.05) and Relative Hemoglobin Content (+16.7%). Red Blood Cell Velocity was found to be increased without statistical significance. Next to the dressing, changes were also significant but less pronounced. CONCLUSION: Intermittent NPWT improves local microcirculation with consecutive enhancement of oxygen supply.

[Remote Ischemic Conditioning - Endogenous Tissue Protection and its Possible Applications in Surgery]. / Remote ischemic Conditioning ­ endogene Gewebeprotektion und ihre Einsatzmöglichkeiten in der Chirurgie.

Tissue perfusion is pivotal to wound healing and tissue regeneration after surgery. Ischemia and reperfusion lead to inflammatory reactions with consecutive tissue damage and necrosis. Multiple conditioning techniques have been described to protect tissue from those damaging mechanisms in the perioperative period. However, most of these fail to meet the requirements of a good therapeutic effect, time and cost efficiency, non-invasiveness and applicability without the need for additional devices or drugs. Remote ischemic conditioning (RIC) is a technique to provide endogenous tissue protection, which fully meets those requirements. Repeated, short cycles of ischemia/reperfusion applied to a circumscribed vascular territory lead to the activation of endogenous signal pathways resulting in increased tolerance to hypoperfusion and limiting the damage caused by reperfusion, even in tissues located far away from the conditioned area. The non-invasive application of the conditioning stimulus requires no more than a pressure cuff, which is placed on the upper arm and is repeatedly inflated to suprasystolic pressures. Different concepts of remote ischemic pre-, peri- and postconditioning enable the usage in both elective and emergency surgical interventions. Based on encouraging experimental studies, the application of RIC has increased in the clinical setting. In addition to studies addressing cardio-, nephro- or neuroprotection there are some initial findings supporting a potential beneficial application in reconstructive microsurgery. This article aims to give an overview of the development, concepts and mechanisms of RIC with a focus on its clinical application in the field of surgery.

Upper extremity ischemia is superior to lower extremity ischemia for remote ischemic conditioning of antero-lateral thigh cutaneous blood flow.

Remote ischemic conditioning (RIC) is known to improve microcirculation in various settings, but little is known about the impact of the amount of ischemic tissue mass or the limb itself. Since ischemia and subsequent necrosis of flaps is one of the most dreaded complications in reconstructive surgery, adjuvant methods to improve microcirculation are desirable. We therefore performed a randomized trial to compare the effect of arm versus leg ischemia for RIC of the cutaneous microcirculation of the antero-lateral thigh. Forty healthy volunteers were randomized to undergo 5 min of ischemia of either the upper or lower extremity, followed by 10 min of reperfusion.Ischemia was induced by a surgical tourniquet applied to the proximal limb, which was inflated to 250 mmHg for the upper and 300 mgHg for the lower extremity. This cycle was repeated a total of three times. Cutaneous microcirculation was assessed by combined laser doppler spectrophotometry on the antero-lateral aspect of the thigh to measure cutaneous blood flow (BF), relative hemoglobin content (rHb), and oxygen saturation (StO2). Baseline measurements were performed for 10 min, after which the ischemia/reperfusion cycles were begun. Measurements were performed continuously and were afterwards pooled to obtain a mean value per minute. Both groups showed significant increases in all three measured parameters of cutaneous microcirculation after three cycles of ischemia/reperfusion when compared to baseline (BF: 95.1% (P < 0.001) and 27.9% (P = 0.002); rHb: 9.4% (P < 0.001) and 5.9% (P < 0.001), StO2: 8.4% (P = 0.045) and 9.4% (P < 0.001). When comparing both groups, BF was significantly higher in the arm group (P = 0.019 after 11 min., P = 0.009 after 45 min). In conclusions, both ischemic conditioning of the upper and lower extremity is able to improve cutaneous BF on the ALT donor site. However, RIC of the upper extremity seems to be a superior trigger for improvement of cutaneous BF.

[Free fasciocutaneous parascapular flap. Coverage of extensive skin and soft tissue defects]. / Freie fasziokutane Paraskapularlappenplastik. Deckung ausgedehnter Haut-Weichteil-Defekte.

Coverage of extensive tissue defects is one of the tasks of plastic surgery. For the surgeon there are a series of possibilities differing in safety level and difficulty. With extensively exposed bones, however, there is mostly the indication for free tissue transfer. In the following case a possibility of wound closure of an extensive defect by one single free flap without preconditioning the tissue is demonstrated.

[Options for reconstructive surgery of the thoracic wall]. / Plastisch-chirurgische Möglichkeiten der Thoraxwandrekonstruktion.

The integrity of the thoracic wall and therefore the protection of the thoracic organs is paramount for survival. This integrity can be compromised by various factors, be it tumours, wound-healing disorders or injuries. An adequate surgical therapy for these entities often requires (partial) resections of the thoracic wall resulting in a loss of its protective function. A safe and timely reconstruction of the thoracic wall is therefore mandatory and can be achieved by means of reconstructive procedures. This article therefore aims to illustrate such reconstructive procedures utilising our own clinical cases while also giving a review of the literature in order to construct an algorithm for the reconstruction procedure.

[Reconstruction options for pelvic defects after abdominal exenteration]. / Defektdeckungsoptionen nach Eviszeration.

Soft tissue defects after oncological pelvic exenteration still represent a significant problem. Because of the anatomic and functional peculiarities, the reconstruction of defects in the pelvic region is challenging and requires a differentiated approach. In this paper, current strategies and options for reconstructive procedures are presented considering preoperative conditions and factors related to surgical planning. The relevance of interdisciplinary collaboration and the resulting benefits are set out. The inclusion of the plastic surgeon already in the preoperative planning of tumour resection is recommended.

Long-term outcome after local recurrence of soft tissue sarcoma: a retrospective analysis of factors predictive of survival in 135 patients with locally recurrent soft tissue sarcoma.

BACKGROUND: The aim of this study was to identify prognostic indicators of survival in patients with locally recurrent soft tissue sarcoma (STS) through a long-term follow-up. METHODS: We retrospectively assessed the relationship between post-recurrence survival (PRS) and potential prognostic factors in 135 patients who had experienced local recurrence, which was suitable for further surgical treatment. The median follow-up time after initial recurrence was 12.3 years (95% confidence interval (CI): 10.4-14.2 years). RESULTS: The 5-year estimate of the PRS rate was 53.1% (95% CI: 44.3-61.2%) for the entire series. Patients with negative margins after the final surgery experienced improved survival compared with patients with positive margins (5-year survival: 46.7% (35.2-57.5%) vs 35.5% (23.4-47.8%); P=0.01). In a multivariate analysis, the significant prognostic indicators for PRS were histologic grade, tumour site, time to initial recurrence, the number of recurrences and the surgical margin status attained at the last resection. CONCLUSIONS: Complete surgical resection with microscopically clear margins is desirable in patients with locally recurrent STS. However, when achieving clear surgical margins will require major functional impairment of the extremity, a radical surgical approach should be weighed for the patient in each case.

[Surgical treatment of extravasation injuries]. / Chirurgische Behandlung von Paravasaten.

OBJECTIVE: Extravasations account for most iatrogenic injuries. The aim of the study was to analyse the results of surgery in patients with extravasations and to draw conclusions for future treatment. MATERIALS AND METHODS: 24 patients with soft-tissue defects after extravasations were treated between 1999 and 2009 in our hospital. The cases were analysed retrospectively. We looked at the drugs causing tissue necrosis and the localisation in relation to the number of interventions and reconstruction complexity. RESULTS: In 83 % (n = 20) of cases tissue necrosis was caused by chemotherapeutic agents, in 8 % (n = 2) by contrast mediums and in 4 % (n = 1) by antibiotics and insulin. 70 % of the cases involved the upper extremity, in 30 % the thoracic wall was affected. 38 % of the extravasations occurred over venous access ports. In mean 2 ±â€Š1.5 interventions were necessary for defect coverage. Two patients died as a direct result of the extravasations, one due to sepsis originating from an infected necrosis area and one due to right-heart failure with prior pulmonary damage. CONCLUSION: Most extravasations can be treated without surgery. In cases of toxic extravasations or pressure-caused ischaemia rapid surgical intervention is necessary to prevent the necrosis progressing to deeper tissue layers.

[The proximally pedicled anterolateral thigh flap for reconstruction of complex soft tissue wounds of the hip and caudal trunk region]. / Die proximal gestielte Anterior-lateral-thigh-Lappenplastik zur Rekonstruktion komplexer Weichteilwunden der Hüft- und kaudalen Rumpfregion.

INTRODUCTION: Groin and lower trunk defects are common problems, especially for elderly patients. While groin defects are often due to prior vascular interventions, trochanteric defects are mainly caused by pressure sores. Plastic reconstructive methods are manifold; however, the pedicled anterolateral thigh (ALT) flap is supposed to be reliable with sustainable results. OBJECTIVE: We present our experiences using the pedicled ALT flap for soft tissue reconstruction in patients with large wounds of the medial and lateral proximal thigh. MATERIALS AND METHODS: A total of 16 patients with groin and lower trunk defects due to prior vascular surgery or pressure sores received locoregional soft tissue reconstruction using a proximal pedicled ALT flap. Patient characteristics, defect size, surgery time, clinical outcome and complication rate were assessed. RESULTS: With the exception of two cases, sufficient soft tissue reconstruction was achieved. In all, 81,3% of patients were categorized as ASA (American Society of Anesthesiologists) 3. The average duration of surgery was 149 min. Length of stay was 18,3 days. A total of 31% needed revision surgery due to limited wound healing problems. Two patients died. All patients showed healed wound conditions when they were discharged. CONCLUSION: The proximal pedicled ALT-flap is a reliable method for soft tissue reconstruction in groin and lower trunk defects. This reconstructive procedure enables reliable wound closure, especially in elderly patients with substantially reduced general health condition.

[Surgical margins in soft tissue sarcoma of the extremities]. / Resektionsgrenzen bei Weichgewebssarkomen der Extremitäten.

Negative surgical margins (R0 resection) play a key role in the prevention of local recurrences of soft tissue sarcoma of the extremities in the multimodal therapy concept. The prognostic relevance for long-term survival is still under dispute. Despite the fact that numerous recommendations and guidelines have existed for over 100 years, strong evidence-based data from prospective randomized studies are still not available today. These studies should include parameters like tumor localization, subtype and biological aggressiveness. Recommendations as to surgical therapy diverge considerably. They range from amputation and compartment resection to centimetre and millimetre surgical margins. The present article analyses currently available data and definitions and discusses the impact on functional restriction, lymph drainage, local recurrence and the perioperative irradiation field. In the absence of surgical standards, it is doubtful whether existing studies and multicenter trials currently underway are valid. Close co-operation between surgeon and pathologist is imperative to further substantiate the significance of histological examinations and resection margins.

[Three case reports of frostbite. Management and literature]. / Drei Fallberichte über Erfrierungen. Management und Literatur.

Due to social and demographic changes as well as new leisure activities, the number of frostbite injuries in the general population is on the increase. Because the injuries are primarily located on the hands and feet the consequences for those concerned are devastating. We provide help in grading and introduce concrete therapeutic regimes for frostbite which are illustrated by three case reports from our clinical experience with varying risk profiles.

Clinical safety and efficacy of a novel thermoreversible polyhexanide-preserved wound covering gel.

BACKGROUND: An ideal topical formulation for wound therapy does not exist. The aim of this study was to develop a novel improved therapeutic option for the treatment of acute and chronic wounds. METHODS: A transparent wound gel which is in a liquid state below and in a gel state at or above room temperature was developed. Forty-four patients were included in this open randomized controlled single-center study. Flammazine served as control in the treatment of skin graft donor sites. Wounds were assessed for time of dressing change and overall satisfaction of patients and health care providers. The data were analyzed using the nonparametric Mann-Whitney test. RESULTS: The wound gel proved to be superior in comparison with Flammazine with respect to wound assessment (p = 0.002), staining (p = 0.007), leaking (p = 0.032) and smell (p = 0.034). Flammazine showed favorable results regarding the parameters dehydration of the dressings (p = 0.012) and wound adherence (p = 0.005). The evaluation of the overall dressing change process showed no significant differences. CONCLUSION: The thermoreversible wound gel containing polyhexanide allows for good handling and wound assessment. This study demonstrated a high satisfaction level of patient and health care providers, and the wound gel proved an effective alternative to commonly used treatments.

Evaluation of a novel polihexanide-preserved wound covering gel on dermal wound healing.

OBJECTIVE: Daily wound assessment, including dressing changes and the removal of old ointments causes discomfort for the patient. We therefore developed a new thermoreversible and transparent gel formulation that allows for filling wounds of different shapes and depths. The aim of the study was to investigate the effect of a wound covering gel on wound healing and the skin's microcirculation. MATERIALS AND METHODS: Investigations were carried out in a standardized and reproducible wound model (hairless mice SKH1/hr, n = 30). Three groups were studied by intravital fluorescence microscopy: treatment with polihexanide-preserved wound covering gel, a formulation containing 3% povidone (PVP)-iodine, and physiological saline for control. Microcirculatory standard parameters were analysed. RESULTS: The non-perfused area vanished within 14 days due to angiogenesis. The venular diameter, oedema formation and functional capillary density showed no significant differences between the three groups. CONCLUSION: The use of the newly developed wound covering gel has no toxic effects on microcirculation and angiogenesis and reveals no significant differences in the overall assessment of microcirculation compared to the control group and the well-established PVP-iodine. The transparent antibacterial wound covering gel allows for direct wound assessment. Due to its thermoreversible gel formulation it enables good wound contact and easy handling.

Anesthesia of the conditioned limb does not abolish the remote ischemic conditioning stimulus on cutaneous microcirculation in humans.

BACKGROUND: Mechanism of remote ischemic conditioning (RIC) remain not fully understood yet. Thus, a clinical trial was performed to assess the neuronal influence on its signal induction. METHODS: RIC was conducted on 45 patients who were randomized into 3 groups. Group A and B underwent brachial plexus anesthesia while RIC was performed on the blocked (A) and non-blocked side (B), respectively. In group C, RIC was conducted before regional anesthesia, thus serving as control group. All measurements were taken contralateral to RIC. The relative increase of microcirculatory parameters compared to baseline was evaluated and compared between the groups. RESULTS: Superficial blood flow (sBF) significantly increased in group A and C but values were higher among group C. Compared to group A, group C showed a significant increase of sBF during the initial 5 minutes of reperfusion (1.75; CI 1.139 - 2.361 vs. 0.97, CI 0.864 - 1.076, p < 0.05). Deep blood flow, tissue oxygen saturation and relative hemoglobin content were marginally influenced by RIC irrespectively of the presence of regional anesthesia. CONCLUSION: Despite regional anesthesia a significant RIC stimulus can be induced although its microcirculatory response is attenuated compared to control. Hence, RIC induction does not merely depend on neuronal signaling.

Lymph node metastases in soft tissue sarcomas: a single center analysis of 1,597 patients.

PURPOSE: The aim of this study was to examine the clinical course of patients with the rare finding of regional lymph node metastasis (RLNM) from soft tissue sarcoma. MATERIALS AND METHODS: Data from 28 out of 1,597 consecutive soft tissue sarcoma patients with RLNM were from the patients' charts and interviewing patients and general practitioners. Survival, including possible influencing factors, was statistically calculated. RESULTS: RLNM was seen in 21.4% for epithelioid sarcoma and 17.6% for clear cell sarcoma. All other entities presented RLNM rates below 10%. At follow-up after an average of 9.6 years, only three patients were alive with no evidence of disease. Survival was independent from surgical resection status of the primary tumor and the RLNM as well as from adjuvant radiation and chemotherapy. Tumor entity as well as the length of the time period from primary to RLNM affect survival. CONCLUSIONS: Surgical treatment as well as radiation and chemotherapy may improve survival in selected cases but probably have their value much more in terms of local disease control and improvement life quality of patients who probably already suffer from an aggressive systemic disease at time of nodal involvement.

[A comparative in vitro study of cell toxicity of clinically used antiseptics]. / Vergleichende In-vitro-Studie zur Zytotoxizität klinisch eingesetzter Antiseptika.

PURPOSE: Local skin antiseptics are the standard of care for chronic and non-healing wounds. However, little is known about their potential toxic properties. This study investigates the impact of three commercially available and widely used antiseptics on vitality and proliferation of human cutaneous cells. MATERIAL AND METHODS: Three antiseptics, Lavasept (PHMB), Octenisept (octenidine) and Betaisodona (PVP-iodine) were tested for their cytotoxic effects towards HaCaT cells, primary human keratinocytes and fibroblasts using MTT assay and BrDU ELISA. RESULTS: Lavasept showed only slight to moderate toxic effects on cellular vitality and proliferation. Ocentisept and Betaisodona induced severe reduction of cell vitality (p<0.05) to 0% surviving fibroblasts at 7.5% (Betaisodona) and 12.5% Octenisept, respectively. Furthermore, poliferative activity was reduced to 0% in keratinocytes at 7.5% concentration of Betaisodona and Ocentisept. CONCLUSION: This study shows that frequently used wound- and skin antiseptics show severe cytotoxic effects towards cutaneous cells. Furthermore, antimicrobial efficacy and toxic properties must be included in the clinical decision process for optimal therapy of chronic wounds. The PHMB solution Lavasept showed best results regarding toxicity in this study.

Ten minutes of ischemia is superior to shorter intervals for the remote ischemic conditioning of human microcirculation.

BACKGROUND: Surgical flaps have become reliable tools in the microsurgical armamentarium, but are still faced with tissue loss due to impaired perfusion which can lead to complete flap failure. Remote Ischemic Conditioning (RIC) has been demonstrated to be an effective way to improve microcirculation in surgical flaps in humans. However, little is known about the optimal amount and length of RIC cycles. OBJECTIVE: Determination of a superior protocol for RIC of cutaneous microcirculation in humans. METHODS: 60 healthy volunteers were randomized into different groups and received a RIC protocol, consisting of three cycles of either 1 second, 1, 5, or 10 minutes of ischemia followed by ten minutes of reperfusion. RIC was applied with a inflatable tourniquet placed on the upper arm. Changes in microcirculation were assessed via combined laser doppler/spectroscopy (O2C device) at the anterior lateral thigh. Relative increase at the end of conditioning vs. baseline measurements was calculated and compared between groups. RESULTS: RIC caused significant changes in cutaneous microcirculation (p < 0.05) which were more pronounced in groups with longer ischemia intervals. The ten minutes group was significantly superior. CONCLUSION: A conditioning protocol containing three cycles of ten minutes of ischemia is superior to protocols with shorter ischemia intervals for RIC of cutaneous microcirculation.

Remote ischaemic conditioning decreases blood flow and improves oxygen extraction in patients with early complex regional pain syndrome.

BACKGROUND: Remote ischaemic conditioning (RIC) is the cyclic application of non-damaging ischaemia leading to an increased tissue perfusion, among others triggered by NO (monoxide). Complex regional pain syndrome (CRPS) is known to have vascular alterations such as increased blood shunting and decreased NO blood-levels, which in turn lead to decreased tissue perfusion. We therefore hypothesized that RIC could improve tissue perfusion in CRPS. METHOD: In this proof-of-concept study, RIC was applied in the following groups: in 21 patients with early CRPS with a clinical history less than a year, in 20 age/sex-matched controls and in 12 patients with unilateral nerve lesions via a tourniquet on the unaffected/non-dominant upper limb. Blood flow and tissue oxygen saturation (StO2 ) were assessed before, during and after RIC via laser Doppler and tissue spectroscopy on the affected extremity. The oxygen extraction fraction was calculated. RESULTS: After RIC, blood flow declined in CRPS (p < 0.01). StO2 decreased in CRPS and healthy controls (p < 0.01). Only in CRPS, the oxygen extraction fraction correlated negatively with the decreasing blood flow (p < 0.05). CONCLUSION: Contrary to our expectations, RIC induced a decrease of blood flow in CRPS, which led to a revised hypothesis: the decrease of blood flow might be due to an anti-inflammatory effect that attenuates vascular disturbances and reduces blood shunting, thus improving oxygen extraction. Further studies could determine whether a repeated application of RIC leads to a reduced hypoxia in chronic CRPS. SIGNIFICANCE: Remote ischaemic conditioning leads to a decrease of blood flow. This decrease inversely correlates with the oxygen extraction in patients with CRPS.

Analysis of biodegradation of copolymer dermis substitutes in the dorsal skinfold chamber of balb/c mice.

PEGT/PBT-block-copolymer dermis substitutes were inserted into dorsal skinfold chambers of balb/c mice (n=36). Scaffolding matrices with 3 different pore diameters (pore diameter: <75 micro m, 75-212 micro m and 250-300 micro m) were analyzed on days 7, 14, and 21 post implantation by scanning electron and light microscopy. The quantification of matrix fragmentation was performed using image-analytical software analySIS(R). The fragmentation rate in scaffolding matrices with a pore size of < 75 micro m was observed to be higher than in matrices of larger pore sizes. Image-analytical evaluation over 21 days revealed a reduction of the copolymer matrix by approximately 32% for the <75 micro m matrices, 23% for the 75-212 micro m matrices and 18% for the matrices, where pore size ranged between 250 micro m and 300 micro m. Twenty-one days after implantation, the matrix pores of 75-212 micro m and 250-300 micro m scaffolds were totally filled by vascularized fibrous tissue. Contrarily, an increased formation of foreign-body giant cells was observed in matrices with pore size <75 micro m. The pore size of the scaffolding PEGT/PBT dermis substitutes affects their degradative behaviour in vivo.