Single-Site Experience with an Automated Artificial Intelligence Application for Left Ventricular Ejection Fraction Measurement in Echocardiography.

Left ventricular ejection fraction (LVEF) is a key parameter in evaluating left ventricular (LV) function using echocardiography (Echo), but its manual measurement by the modified biplane Simpson (MBS) method is time consuming and operator dependent. We investigated the feasibility of a server-based, commercially available and ready-to use-artificial intelligence (AI) application based on convolutional neural network methods that integrate fully automatic view selection and measurement of LVEF from an entire Echo exam into a single workflow. We prospectively enrolled 1083 consecutive patients who had been referred to Echo for diagnostic or therapeutic purposes. LVEF was measured independently using MBS and AI. Test-retest variability was assessed in 40 patients. The reliability, repeatability, and time efficiency of LVEF measurements were compared between the two methods. Overall, 889 Echos were analyzed by cardiologists with the MBS method and by the AI. Over the study period of 10 weeks, the feasibility of both automatic view classification and seamlessly measured LVEF rose to 81% without user involvement. LVEF, LV end-diastolic and end-systolic volumes correlated strongly between MBS and AI (R = 0.87, 0.89 and 0.93, p < 0.001 for all) with a mean bias of +4.5% EF, -12 mL and -11 mL, respectively, due to impaired image quality and the extent of LV function. Repeatability and reliability of LVEF measurement (n = 40, test-retest) by AI was excellent compared to MBS (coefficient of variation: 3.2% vs. 5.9%), although the median analysis time of the AI was longer than that of the operator-dependent MBS method (258 s vs. 171 s). This AI has succeeded in identifying apical LV views and measuring EF in one workflow with comparable results to the MBS method and shows excellent reproducibility. It offers realistic perspectives for fully automated AI-based measurement of LVEF in routine clinical settings.

Overall Complication Rates of DIEP Flap Breast Reconstructions in Germany-A Multi-Center Analysis Based on the DGPRÄC Prospective National Online Registry for Microsurgical Breast Reconstructions.

While autologous breast reconstruction has gained momentum over recent years, there is limited data on the structure and quality of care of microsurgical breast reconstruction in Germany. Using the breast reconstruction database established by the German Society of Plastic, Reconstructive and Aesthetic Surgeons (DGPRÄC), the presented study investigated the overall outcomes of deep inferior epigastric perforator (DIEP) flap reconstructions in Germany. Data of 3926 patients and 4577 DIEP flaps performed by 22 centers were included in this study. Demographics, patient characteristics, perioperative details and postoperative outcomes were accounted for. Centers performing < Ø 40 (low-volume (LV)) vs. ≥ Ø 40 (high-volume (HV)) annual DIEP flaps were analyzed separately. Overall, total and partial flap loss rates were as low as 2.0% and 1.1% respectively, and emergent vascular revision surgery was performed in 4.3% of cases. Revision surgery due to wound complications was conducted in 8.3% of all cases. Mean operative time and length of hospital stay was significantly shorter in the HV group (LV: 385.82 min vs. HV: 287.14 min; LV: 9.04 (18.87) days vs. HV: 8.21 (5.04) days; both p < 0.05). The outcome and complication rates deduced from the national registry underline the high standard of microsurgical breast reconstruction on a national level in Germany.

[Quality assurance in breast reconstruction - Establishment of a prospective national online registry for microsurgical breast reconstructions]. / Qualitätssicherung in der Brustrekonstruktion ­ Etablierung eines prospektiven nationalen Onlineregisters für mikrochirurgische Brustrekonstruktionen.

BACKGROUND: The loss of a breast, and thus of the female body shape, is often extremely traumatising for women affected. Although free flap grafts have become the gold standard in reconstructive breast surgery, it has not been possible to date to unequivocally document their superiority over conventional alternative techniques. To date, there are no data on the care situation in Germany. Neither the number of reconstructions nor the proportion of the individual techniques is known. A prospective online registry has been set up in order to systematically collect and transparently present the structure and quality of care. The long-term goals are to record the existing quality of care, improve deficits and to certify centres with the appropriate expertise to establish a high level of care nationwide. METHODS: For this purpose, the German Society of Plastic, Reconstructive and Aesthetic Surgeons (DGPRÄC) has set up an internet-based database in which treatment data are recorded anonymously. As part of a certification process, auditors checked structure quality, compliance with specifications, and the stringency of the data entered in comparison with the hospital's internal documentation. If the evaluation is positive, the DGPRÄC quality seal is awarded. RESULTS: Since its introduction in 2012, the database has provided validated information. Initially, only a few departments were prepared to present their results transparently. However, the number has grown steadily in recent years. As a result, the quality recording assumed a pioneering function nationwide and can now be used as a reliable source of information by patients and doctors. The DGPRÄC website features a map of the centres, which are colour-coded according to their respective qualifications. It is thus possible to find a qualified plastic surgeon with comprehensive expertise in acceptable proximity to every oncological breast centre. CONCLUSION: The database provides an overview of the quality of the various surgical techniques and thus the possibility of serious self monitoring and scientific analysis. The systematic collection of data has contributed to strengthening the position of plastic surgery in the field of reconstructive breast surgery. However, the financial and personnel resources required to establish the database were clearly underestimated.

[Consensus of the German-Speaking Society for Microsurgery of Peripheral Nerves and Vessels (DAM) on minimum standards for microsurgical training courses and accreditation - Minimum Standards for Microsurgical Training Courses and Accreditation]. / Konsensus der Deutschsprachigen Arbeitsgemeinschaft für Mikrochirurgie der peripheren Nerven und Gefäße (DAM) für Mindeststandards mikrochirurgischer Trainings- und Übungskurse zur Vergabe eines Qualitätssiegels.

Microsurgical training courses are an integral part of surgical education and training. Due to the changes in the surgical everyday routine, the competence and skills training outside the operating room has an increasingly important status. Multi-day, hands-on exercises with different models of increasing difficulty use artificial, avital and vital microsurgical models. The skills are evaluated with regard to fine motor skills as well as orientation in space and low-tremor motion sequences as well as bimanual manipulation exercises by means of "lobal rating scales". However, with numerous course offerings in German-speaking countries, there are no uniform and transparent contents and evaluation standards to reflect the quality of the courses. At a consensus meeting, minimum requirements for the contents of microsurgical training courses in the context of continuing medical education were defined and drafted as a German-language consensus in order to award a DAM quality seal. The parameters include the definition of targets, the existence of a scripts, the number of hours used, models used, practical exercise time on the microscope, trainer to participant ratio, types of anastomosis or coaptation (artery, vein, nerve, lymph vessel), application of a global rating scale , examination (grade/passed - failed), participant certificate and course evaluation. With the aim to meet the available courses/course concepts to maintain or improve the quality of education and training, the assignment of a "Basic" and an "Advanced" quality seal has been defined. The further stepwise development of the courses is necessary to sustain all skills and competencies for future microsurgeons. Integration of validated microsurgical simulators may reduce animal use and thus contribute to the ethical responsibility. The introduction of quality seals for microsurgical training courses should strengthen the transparency and commitment of participants and provide support to course providers with appropriately substantiated content through DAM.

Oncoplastic breast-conserving surgery: More relevant than ever? Results of a survey among breast surgeons.

PURPOSE: Oncoplastic breast-conserving surgery has been part of clinical routine for several years without an internationally accepted nomenclature, standardization or a systematic evaluation of single surgical procedures. METHODS: We carried out a structured survey of breast surgeons (n = 50) during the annual meeting of the German Society for Senology in Berlin 2017. In the run-up to the event, 10 questions were determined and released for an anonymous survey during the consensus meeting. RESULTS: Most surgeons participating in the consensus meeting had an expertise of more than 200 oncologic breast surgeries in the last 3 years and approved the need of a higher rate of standardization in oncoplastic techniques. From the oncological standpoint, oncoplastic surgery is considered safe with a comparable rate of compilations as seen in conventional breast-conserving procedures. Most surgeons approve that using oncoplastic surgery, higher rates of breast conservation and improved aesthetic results can be accomplished. The majority of the participants would endorse a more systematic review of subjective aesthetic results in clinical routine. CONCLUSIONS: A higher degree in standardization of oncoplastic breast surgery is required for surgical-technical, educational, and scientific reasons as well as for a more differentiated monetary compensation of the surgical procedures. This process has already been started.

Interdisciplinary Screening, Diagnosis, Therapy and Follow-up of Breast Cancer. Guideline of the DGGG and the DKG (S3-Level, AWMF Registry Number 032/045OL, December 2017) - Part 2 with Recommendations for the Therapy of Primary, Recurrent and Advanced Breast Cancer.

Purpose The aim of this official guideline coordinated and published by the German Society for Gynecology and Obstetrics (DGGG) and the German Cancer Society (DKG) was to optimize the screening, diagnosis, therapy and follow-up care of breast cancer. Method The process of updating the S3 guideline published in 2012 was based on the adaptation of identified source guidelines. They were combined with reviews of evidence compiled using PICO (Patients/Interventions/Control/Outcome) questions and with the results of a systematic search of literature databases followed by the selection and evaluation of the identified literature. The interdisciplinary working groups took the identified materials as their starting point and used them to develop suggestions for recommendations and statements, which were then modified and graded in a structured consensus process procedure. Recommendations Part 2 of this short version of the guideline presents recommendations for the therapy of primary, recurrent and metastatic breast cancer. Loco-regional therapies are de-escalated in the current guideline. In addition to reducing the safety margins for surgical procedures, the guideline also recommends reducing the radicality of axillary surgery. The choice and extent of systemic therapy depends on the respective tumor biology. New substances are becoming available, particularly to treat metastatic breast cancer.

Interdisciplinary Screening, Diagnosis, Therapy and Follow-up of Breast Cancer. Guideline of the DGGG and the DKG (S3-Level, AWMF Registry Number 032/045OL, December 2017) - Part 1 with Recommendations for the Screening, Diagnosis and Therapy of Breast Cancer.

Purpose The aim of this official guideline coordinated and published by the German Society for Gynecology and Obstetrics (DGGG) and the German Cancer Society (DKG) was to optimize the screening, diagnosis, therapy and follow-up care of breast cancer. Methods The process of updating the S3 guideline dating from 2012 was based on the adaptation of identified source guidelines which were combined with reviews of evidence compiled using PICO (Patients/Interventions/Control/Outcome) questions and the results of a systematic search of literature databases and the selection and evaluation of the identified literature. The interdisciplinary working groups took the identified materials as their starting point to develop recommendations and statements which were modified and graded in a structured consensus procedure. Recommendations Part 1 of this short version of the guideline presents recommendations for the screening, diagnosis and follow-up care of breast cancer. The importance of mammography for screening is confirmed in this updated version of the guideline and forms the basis for all screening. In addition to the conventional methods used to diagnose breast cancer, computed tomography (CT) is recommended for staging in women with a higher risk of recurrence. The follow-up concept includes suggested intervals between physical, ultrasound and mammography examinations, additional high-tech diagnostic procedures, and the determination of tumor markers for the evaluation of metastatic disease.

[Breast reconstruction with the free TRAM or DIEP flap ­ What is the current standard? Consensus Statement of the German Speaking Working Group for Microsurgery of the Peripheral Nerves and Vessels]. / Brustrekonstruktion mit freien TRAM oder DIEP Lappen ­ Was ist zeitgemäßer Standard?

The most common donor-site for autologous breast reconstruction is the abdomen. Over the past several decades technical advances have resulted in the development of flaps that have been associated with a progressive decrease in abdominal wall morbidity. However, controversy exists related to the differences between muscle-sparing (MS)-TRAM and deep inferior epigastric perforator (DIEP) flaps. Hence, the question which approach should be considered standard of care remains unanswered. To address this question the current literature and published evidence was critically reviewed and discussed by an expert panel at the 39th Annual Meeting of the German-speaking Society for Micro surgery of the Peripheral Nerves and Vessels (DAM). Based on this discussion a consensus statement was developed that incorporates contemporary data regarding postoperative complication rate, donor site morbidity, as well as expert opinion regarding technical details in autologous breast reconstruction with free TRAM and DIEP flaps.

First international consensus conference on standardization of oncoplastic breast conserving surgery.

PURPOSE: To obtain consensus recommendations for the standardization of oncoplastic breast conserving surgery (OPS) from an international panel of experts in breast surgery including delegates from the German, Austrian and Swiss societies of senology. METHODS: A total of 52 questions were addressed by electronic voting. The panel's recommendations were put into context with current evidence and the report was circled in an iterative open email process until consensus was obtained. RESULTS: The panelists considered OPS safe and effective for improving aesthetic outcomes and broadening the indication for breast conserving surgery (BCS) towards larger tumors. A slim majority believed that OPS reduces the rate of positive margins; however, there was consensus that OPS is associated with an increased risk of complications compared to conventional BCS. The panel strongly endorsed patient-reported outcomes measurement, and recommended selected scales of the Breast-Q™-Breast Conserving Therapy Module for that purpose. The Clough bi-level classification was recommended for standard use in clinical practice for indicating, planning and performing OPS, and the Hoffmann classification for surgical reports and billing purposes. Mastopexy and reduction mammoplasty were the only two recognized OPS procedure categories supported by a majority of the panel. Finally, the experts unanimously supported the statement that every OPS procedure should be tailored to each individual patient. CONCLUSIONS: When implemented into clinical practice, the panel recommendations may improve safety and effectiveness of OPS. The attendees agreed that there is a need for prospective multicenter studies to optimize patient selection and for standardized criteria to qualify and accredit OPS training centers.

An Appraisal of Internal Mammary Artery Perforators as Recipient Vessels in Microvascular Breast Reconstruction-An Analysis of 515 Consecutive Cases.

BACKGROUND: The usage of internal mammary artery perforators (IMAPs) has been described in autologous breast reconstruction although IMAPS are not yet considered standard recipient vessels. It remains unclear if these vessels can be safely used in large flaps after radiation therapy or in delayed breast reconstruction. METHODS: Over a 2-year period, 515 free flaps for autologous breast reconstruction were performed on 419 patients by 2 surgeons (S1 and S2). In a retrospective analysis, time of reconstruction, ischemia time, flap weight, diameter of couplers, and complications were analyzed. All 515 flaps were compared in a subset with regard to the 2 surgeons: S1 who always used the IMA as a recipient vessel and S2 who attempted IMAP use if possible. RESULTS: Of all 515 flaps, 424 were abdominal flaps and 91 flaps were from the upper thigh. Three hundred six cases were immediate reconstructions, and 112 were delayed reconstructions. In 97 cases, implants were converted to autologous tissue. In 112 cases, the IMAPs were used; of these, 82 were immediate and 17 were delayed reconstructions, and in 13 cases, implants were removed. Thirty-five percent of all anastomoses to IMAPs had previous radiation therapy. The flap failure rate was 1.9%. In none of these cases, the IMAPs were used. S1 never used the IMAP, and S2 used the IMAP in 37% of all of his flaps. CONCLUSIONS: IMAPs were safely used in all kinds of reconstructions and after radiation therapy, with no flap failure or negative effects on mastectomy skin flap perfusion. Using the IMAPs as recipient vessels is a further step toward simplifying microsurgical breast reconstruction.

High-dose vitamin C treatment reduces capillary leakage after burn plasma transfer in rats.

Oxidative stress after burn injuries leads to systemic capillary leakage and leukocyte activation. This study evaluates whether antioxidative treatment with high-dose vitamin C leads to burn edema reduction and prevention of leukocyte activation after burn plasma transfer. Donor rats underwent a burn (n = 7; 100 degrees C water, 12 seconds, 30% body surface area) or sham burn (37 degrees C water; n = 2) procedure and were killed after 4 hours for plasma harvest. This plasma was administered to study rats (continuous infusion). Rats were randomized to four groups (n = 8 each; burn plasma alone [BP]; burn plasma/vitamin C-bolus 66 mg/kg and maintenance dose 33 mg/kg/hr [VC66]; burn plasma/vitamin C-bolus 33 mg/kg and maintenance dose 17.5 mg/kg/hr [VC33]; and sham burn plasma [SB]). Intravital fluorescence microscopy in the mesentery was performed at 0, 60, and 120 minutes for microhemodynamic parameters, leukocyte adherence, and fluorescein isothiocyanate-albumin extravasation. No differences were observed in microhemodynamics at any time. Burn plasma induced capillary leakage, which was significantly higher compared with sham burn controls (P < .001). VC66 treatment reduced microvascular barrier dysfunction to sham burn levels, whereas VC33 had no significant effect. Leukocyte sticking increased after burn plasma infusion, which was not found for sham burn. Vitamin C treatment did not influence leukocyte activation (P > .05). Burn plasma transfer leads to systemic capillary leakage. High-dose vitamin C treatment (bolus 66 mg/kg and maintenance dose 33 mg/kg/hr) reduces endothelial damage to sham burn levels, whereas half the dose is inefficient. Leukocyte activation is not influenced by antioxidative treatment. Therefore, capillary leakage seems to be independent from leukocyte-endothelial interactions after burn plasma transfer. High-dose vitamin C should be considered for parenteral treatment in every burn patient.

Burn plasma transfer induces burn edema in healthy rats.

Thermal injuries greater than 20% body surface area (BSA) result in systemic shock with generalized edema in addition to local tissue destruction. Burn shock is induced by a variety of mediators, mainly immunomodulative cytokines. This experimental study evaluates if burn shock can be induced in healthy rats by transfer of burn plasma (BP) with mediators. Thermal injury was induced by hot water (100 degrees C water, 12 s, 30% BSA) in male syngenic Wistar rats. Donor rats were killed 4 h posttrauma, and BP was harvested. Burn plasma was transferred to healthy animals by continuous intravenous infusion in three types of dilution (100%, 10%, and 1%). Positive controls were directly examined 4 h after thermal injury, and negative control rats had a continuous infusion done with sham burn (SB) plasma (37 degrees C water, 12 s, 30% BSA). Afterwards, intravital fluorescence microscopy was performed in postcapillary mesenteric venules at 0, 60, and 120 min. Edema formation was assessed by relative changes over time in fluorescence intensity of fluorescein isothiocyanate-albumin in the intravascular versus the extravascular space. The interactions of leucocytes and endothelium were evaluated by quantification of leukocyte sticking. Additionally, microhemodynamic (volumetric blood flow, erythrocyte velocity, venular wall shear rate, venular diameters) and macrohemodynamic parameters (blood pressure, heart frequency, temperature) were assessed online (arterial catheter). For statistics, an ANOVA was performed with Bonferroni adjustment procedure. Differences were considered significant when P < 0.05. There are no statistically significant differences in microhemodynamics or macrohemodynamics between study groups. Burn plasma infusion and thermal injury lead to significant increases in fluorescein isothiocyanate-albumin extravasation, whereas SB plasma shows no significant changes. Even BP diluted in 0.9% saline (10% and 1%) results in a similar transvascular flux of plasma proteins as direct thermal injury. Differences between positive controls and BP infusion are not significant, whereas all groups are statistically different from the SB group (P<0.05). Leukocyte sticking is significantly increased in all groups except the SB group, and the number of adherent leukocytes is dose dependent. The present study demonstrates that as early as 4 h after thermal injury, there are sufficient factors (e.g., cytokines) in BP to induce systemic burn shock in healthy rats even in diluted plasma (1%). However, the "key" cytokines are not identified at this point. The burned tissue is no longer required for burn shock induction, and the pathophysiologic process seems to be self-perpetuating as early as 4 h posttrauma. Leukocytes are activated by thermal injury and BP infusion. The role of leukocyte-endothelium interactions for edema formation remains uncertain and requires further investigation.

An innovative treatment concept for free flap reconstruction of complex central chest wall defects--the cephalic-thoraco-acromial (CTA) loop.

BACKGROUND: Loco-regional flaps are the method of choice for chest wall reconstruction. However there is a selected group of patients who require free flap reconstruction, when all other options are used up. A small subgroup of these patients was identified where the commonly used recipient vessels (Internal mammary A. + V., Thoraco-dorsal A. + V.) were no longer available. PATIENT AND METHOD: This group comprised 16 seriously ill patients in the period from 2000 to 2004. Underlying diseases were sternum osteomyelitis (10x), tumor (2x), and osteo-radionecrosis (4x). There were 10 women and 6 men with mean age 62.4 years. All patients were classified as ASA III and IV. Fourteen patients received a TFL flap, two patients a vertical rectus myocutaneous flap (VRAM). Recipient vessels were created with a temporary A-V loop between the cephalic vein and the thoraco-acromial artery (CTA-loop). RESULTS: No flap was lost and two had to be revised successfully for thrombosis of the arterial anastomosis. Mean operation time was 6.1 (4.7-8.4) h. Average time for ventilatory support was 56 (4-338) h. Five patients died within 6 months postoperatively due their underlying advanced disease (n = 3) or multiple organ failure (n = 2). CONCLUSION: The new concept of creating recipient vessels for free flap reconstruction of complex thoracic wall defects proved to be safe and reliable. The CTA loop allowed for unhurried flap dissection, best possible flap positioning, and straightforward end-end anastomoses in these seriously sick patients. The outcome with respect to complications and survival justifies the operative effort.

Vein graft anastomoses with magnets.

BACKGROUND: Performing vascular anastomoses requires complete circumferential access and is time-consuming and technically challenging. The purpose of our study was to assess a sutureless magnetic device for anastomosing vein grafts. METHODS AND RESULTS: Oval magnets with a lumen were placed in six male foxhounds. The femoral artery was ligated and an 8 cm length of femoral vein was harvested and reversed. After a 4 mm venotomy or arteriotomy, one magnet was inserted into each vessel lumen and a second magnet was placed outside the vessel but aligned directly over the intraluminal magnet, forming a magnetic port in each vessel. The graft and target vessels were then allowed to self-align and seal, creating a side-to-side anastomosis. Patency was confirmed with duplex Doppler ultrasound scans after 6 and 13 weeks and during explantation after 14 weeks. At that time, the contralateral femoral vein was harvested and an acute graft was created as a control. Macroscopically there was no sign of stenoses or aneurysms. After explant, saline was perfused through all grafts and the hydrodynamic resistance was quantified. There was no significant difference in resistance between the acute and 14-week grafts indicating stenosis. Microscopic examination of 14-week anastomoses showed that all blood-contacting surfaces were well-endothelialised. CONCLUSIONS: The magnetic vascular coupler allowed sutureless anastomoses between blood arteries and veins. This device might prove useful for anastomosis of large and small vessels, as well as for anastomosis or approximation of non-vascular structures such as peripheral nerves, fallopian tubes or ureters.

Gluteal artery perforator flaps.

Perforator flaps have allowed the transfer of a patient's own skin and fat in a reliable manner with minimal donor site morbidity for more than a decade. They represent the latest in the evolution of soft tissue flaps and provide the reconstructive microsurgeon with more freedom to select a donor site that matches the skin color, thickness, texture, and subcutaneous fat quality of the recipient site. More attention can be paid to the aesthetic quality of the reconstruction. This article focuses on buttock flaps for breast reconstruction and covers aspects such as patient evaluation, selection, preparation, surgical technique, and complications of superior gluteal artery perforator and inferior gluteal artery perforator flaps.

Outcome assessment after reconstruction of complex defects of the forearm and hand with osteocutaneous free flaps.

BACKGROUND: Complex defects of the forearm and hand often require microvascular reconstruction with osteocutaneous free flaps for limb salvage. METHODS: Fifteen patients with osseous and soft-tissue defects of the forearm and hand were treated with osteocutaneous flaps (1992 to 2004) and evaluated for postoperative results. Assessment focused on range of motion, pain, grip strength, and Disabilities of Arm, Shoulder, and Hand questionnaire score. Donor- and recipient-site morbidity was documented. RESULTS: The defects resulted from trauma, infection, or malignancy. Reconstruction was possible by microvascular osteoseptocutaneous fibula transplantation (n = 8), osteocutaneous scapular or parascapular flaps(n = 6), and osteocutaneous lateral arm flap (n = 1). The average patient age was 38 years. The median osseous defect was 11.7 cm, and all patients needed additional soft-tissue reconstruction. All defects could be reconstructed in a one-step procedure after serial débridement or oncologic resection. Patients' hand function was markedly reduced compared with the unaffected extremity, but functional results were still satisfactory, with a mean Disabilities of Arm, Shoulder, and Hand score of 25.3 reflecting a moderate disability in activities of daily living. Two patients developed pseudarthrosis, and one had to undergo an ablation procedure because of persistent infection. Two patients developed wound dehiscence at the donor site, and one patient required a fasciotomy due to an imminent compartment syndrome after fibula harvest. For all patients, the functional results were acceptable when the potential alternatives were taken into consideration. This was also reflected by a high individual satisfaction rate. CONCLUSION: This analysis demonstrates that limb salvage with osteocutaneous free flaps is the treatment of choice for three-dimensional defects of the forearm and hand.

Reduction of skeletal muscle injury in composite tissue allotransplantation by heat stress preconditioning.

Ischemia-reperfusion injury is a dominant factor limiting tissue survival in any microsurgical tissue transplantation, a fact that also applies to allogeneic hand transplantation. The clinical experience of the 12 human hand transplantations indicates that shorter ischemia times result in reduced tissue damage and, ultimately, in better hand function. Heat stress preconditioning and the accompanying up-regulation of the heat shock protein 72 have been shown to reduce the ischemia-reperfusion injury following ischemia of various organs, including organ transplantation. The aim of this study was to reduce the ischemia-reperfusion injury in a model of composite tissue allotransplantation. Allogeneic hind limb transplantations were performed from Lewis (donor) to Brown-Norway rats. Donor rats in group A (n = 10) received a prior heat shock whereas rats in group B (n = 10) did not receive any prior heat shock. Group C served as a control group without transplantation. The transplantations were performed 24 hours after the heat shock, at which time the heat shock protein 72 was shown to be up-regulated. The outcome was evaluated 24 hours after transplantation by nitroblue tetrazolium staining and wet-to-dry weight ratio of muscle slices (anterior tibial muscle). The nitroblue tetrazolium staining showed a significant reduction of necrotic muscle in group A (prior heat shock) (p = 0.005). The wet-to-dry ratio was significantly reduced in group A (prior heat shock), indicating less muscle edema and less tissue damage (p = 0.05). Heat shock preconditioning 24 hours before an ischemic event leads to an up-regulation of heat shock protein 72 in muscle and to a tissue protection reducing ischemia-reperfusion injury in composite tissue transplantation.