Sex disparities in popliteal artery aneurysms.

OBJECTIVE: Only 5% of patients with popliteal artery aneurysms (PAAs) are female. Evidence on PAA treatment and outcomes in women is therefore scarce. The POPART Registry provides one of Europe's largest data collections regarding PAA treatment. Data on clinical presentation, aneurysm morphology, and perioperative outcomes after open surgical PAA repair in women will be presented. METHODS: POPART is a multicenter, noninterventional registry for open and endovascular PAA repair, with 42 participating centers in Germany and Luxembourg. All patients aged >18 years who have been treated for PAA since 2010 are eligible for study inclusion. Data collection is based on an online electronic case report form. RESULTS: Of the 1236 PAAs, 58 (4.8%) were in women. There were no significant differences in age or cardiopulmonary comorbidities. However, female patients had a lower prevalence of contralateral PAAs and abdominal aortic aneurysms (P < .05). PAAs in women were more likely to be symptomatic before surgery (65.5% vs 49.4%; P = .017), with 19% of women presenting with acute limb ischemia (vs 11%; P = .067). Women had smaller aneurysm diameters than men (22.5 mm vs 27 mm; P = .004) and became symptomatic at smaller diameters (20 mm vs 26 mm; P = .002). Only 8.6% of women and 11.6% of men underwent endovascular aneurysm repair (P > .05); therefore, the perioperative outcome analysis focused on open surgical repair. In total, 23.5% of women and 16.9% of men developed perioperative complications (P > .05). There were no differences in major cardiovascular events (P > .05), but women showed a higher incidence of impaired wound healing (15.7% vs 7.2%; P = .05) and major amputation (5.9% vs 1.1%; P = .027). Female sex was significantly associated with the need for nonvascular reinterventions within 30 days after surgery (odds ratio: 2.48, 95% confidence interval: 1.26-4.88), whereas no significant differences in the odds for vascular reinterventions were observed (odds ratio: 1.98, 95% confidence interval: 0.68-5.77). In the multiple logistic regression model, female sex, symptomatic PAAs, poor quality of outflow vessels, and graft material other than vein graft were independently associated with perioperative reinterventions. CONCLUSIONS: Women have smaller PAAs, are more likely to be symptomatic before treatment, and are more often affected by nonvascular reinterventions in the perioperative course. As our understanding of aneurysmatic diseases in women continues to expand, sex-specific treatment strategies and screening options for women in well-selected cohorts with modified screening protocols should be continuously re-evaluated.

Endoscopic mucosal resection and endoscopic submucosal dissection with an external additional working channel (EMR+ and ESD+) are equivalent to using a double-channel endoscope: a systematic evaluation in a porcine ex vivo model.

BACKGROUND AND AIMS: With an external additional working channel (AWC) endoscopic mucosal resection (EMR) as well as endoscopic submucosal dissection (ESD) can be extended to techniques termed "EMR+" and "ESD+." These novel techniques are systematically compared to EMR and ESD under the use of a double-channel endoscope (DC). METHODS: Our trial was conducted prospectively in a pre-clinical porcine animal model (EASIE-R simulator) with standardized gastric lesions measuring 3 or 4 cm. RESULTS: EMR+ and EMR DC showed both good results for 3 cm lesions with no adverse events and an en bloc resection rate of 73.33% (EMR+) and 60.00% (EMR DC, p = 0.70). They came to their limits in 4 cm lesions with muscularis damages of 20.00% (EMR+), 13.33% (EMR DC, p ≥ 0.99) and decreasing en bloc resection rates of 60.00% (EMR+) and 46.67% (EMR DC, p = 0.72). ESD+ and ESD DC were both reliable concerning en bloc resection rates (100% in all groups) and adverse events (0.00% in 3 cm lesions, 12.50% muscularis damages in both ESD+ and ESD DC in 4 cm lesions). Resection time was slightly shorter in all groups with the AWC compared to DC although only reaching significance in 3 cm ESD lesions (p < 0.05*). CONCLUSIONS: With the AWC, a standard endoscope can easily be transformed to double-channel functionality. We could show that EMR+ and ESD+ are non-inferior to EMR and ESD under the use of a double-channel endoscope. Consequently, the AWC presents an affordable alternative to a double-channel endoscope for both EMR and ESD.

[Adequate Perioperative Use of Antibiotics in Thoracic Surgery]. / Rationale perioperative Antibiotikatherapie in der Thoraxchirurgie.

INTRODUCTION: Infectious complications after lung resections pose a high burden of perioperative morbidity and mortality. Among other factors, perioperative antibiotic prophylaxis and management of a postoperative pneumonia have an impact on patient outcome. We developed a local clinical pathway for adequate perioperative use of antibiotics. METHODS: We analysed respiratory samples of 200 patients taken before and after lung resection performed in our lung clinic from October 2013 till October 2014. The clinical pathway was based on our local pathogen and resistance pattern as well as on current guidelines and on the principals of antibiotic stewardship. RESULTS: Gram negative bacteria were the predominant pathogens that grew from the samples in the preoperative phase (62%), as well as in the postoperative phase (78%). A significant number of these bacteria showed intrinsic resistance against the commonly used antibiotics for perioperative prophylaxis. This was the case for both the preoperative phase (21%) and the postoperative phase (39%). These findings were integrated into the local clinical pathway. CONCLUSION: The commonly used antibiotics for perioperative prophylaxis in thoracic surgery cover only some of the pathogens responsible for preoperative airway colonisation and postoperative pneumonia. Therefore, perioperative antibiotic prophylaxis should be given as a single shot just before surgery and postoperative pneumonia should be treated as a hospital acquired pneumonia with respect to the local pathogen and resistance pattern.

Organization of the German Army Medical Service 1914-1918 and the role of academic surgeons.

SUMMARY: The First World War, mankind's first high-technology conflict, resulted in unprecedented mass mortality. Medical services were confronted with overwhelming challenges in treating casualties from mobile warfare, trench warfare, battles on different fronts and infectious diseases. In this article, we give an overview of the organization of the German army medical service using contemporary reports in order to describe surgical and medical developments that originated from the experience. Consulting physicians (beratende arzte), many of whom were internationally known specialists, had a great impact; some of their innovations remain in use today, including the scientific evaluation of contemporary conflicts, the implementation of different echelons of care with a fast movement of patients, and the treatment of penetrating wounds. This article includes an appendix, available at canjsurg.ca/005118-a1, with more information.

[Management of Vascular Trauma in Military Conflicts and Terrorist Attacks]. / Management von Gefäßverletzungen bei militärischen Konflikten und Terroranschlägen.

In war and terror attacks, up to 12% of all casualties suffer a severe vascular injury. Therefore, management of vascular trauma is closely associated with lessons learned during the wars of the 20th and 21st century. This article discusses military aspects of vascular trauma based on historical developments and introduces current standards in military vascular surgery. Up to Word War II, ligation was the predominant therapy for severe vascular trauma. Beginning in the Korean and Vietnam Wars, arterial reconstruction became more and more feasible. This development - in conjunction with rapid helicopter evacuation - decreased the former amputation rate of almost 50% to less than 15%. Nevertheless, exsanguination still remains the major cause of death among casualties with potentially survivable injuries. Standard application of tourniquets, haemostyptica, and balloon occlusion of the aorta improved survival rate. Meanwhile, damage control principals are essential for Forward Surgical Teams and the use of temporary intravascular shunts is well implemented in combat settings. In many armed forces, sophisticated training programs ensure the necessary competence in vascular surgery for all military surgeons deployed. Military surgery provided ample evidence and experience in the management of major vascular trauma over the last century. Much of this knowledge has been translated to civilian health providers and ongoing developments in the military still influence the management of severe vascular trauma.

Closed-incision negative pressure therapy to reduce groin wound infections in vascular surgery: a randomised controlled trial.

Groin wound infections pose a major problem in vascular surgery. Closed-incision negative pressure therapy (ciNPT) was especially designed for the management of incisions at risk of surgical site infections. The aim of this study was to investigate whether ciNPT is able to reduce the incidence of wound infections after vascular surgery. Data on 132 consecutive patients, scheduled for vascular surgery with a longitudinal femoral cutdown, were collected prospectively. All patients were randomised either to the ciNPT group (n = 64) or the control group (n = 68) with conventional dressing. In the ciNPT group, the foam dressing was applied intraoperatively and removed after 5 days. The control group received an absorbent dressing. All wounds were evaluated after 5 and 42 days. Infections were graded according the Szilagyi classification (I-III°). There were no significant differences between both groups considering patient characteristics. Indications for surgery were peripheral arterial disease in 95% (125/132) and aneurysm in 5% (7/132). The overall infection rates were 14% (9/64) in the ciNPT group and 28% (19/68) in the control group (P = 0·055). Early infections were observed in 6% (4/64) of the ciNPT group and 15% (10/68) of the control group (P = 0·125). ciNPT did not reduce infection rates associated with different risk factors for infection. While the experiences with the ciNPT device were encouraging, the study fails to provide evidence of the efficacy of the device to reduce groin wound infections after vascular surgery. It illustrates far more that larger multicentre studies are required and appear promising to provide further evidence for the use of ciNPT.

Quality-of-life evaluation in chronic wounds: comparative analysis of three disease-specific questionnaires.

The study directly compared the feasibility and performance of three instruments measuring health-related quality of life (HRQoL) in chronic ulcers: the Freiburg Life Quality Assessment for wounds (FLQA-w), the Cardiff Wound Impact Schedule (CWIS) and the Würzburg Wound Score (WWS). The questionnaires were evaluated in a randomly assigned order in a longitudinal observational study of leg ulcer patients. Psychometric properties (internal consistency, responsiveness and construct validity) were analysed. Patient acceptance was recorded. Analysis of n = 154 patients revealed good internal consistency (Cronbach's alpha ≥ 0·85) for all instruments. There were minor floor effects in all questionnaires (<1%) and some ceiling effects in the CWIS. Construct validity was satisfactory, for example, correlation with EuroQoL-5D was r = 0·70 in the FLQA-w, r = 0·47/0·67/0·68 in the CWIS dimensions and r = 0·60 in the WWS. The proportion of missing values was higher in the CWIS, and overall patient acceptance was highest in the FLQA-w for wounds (54% best preferences) and lowest in the WWS (14%). In conclusion, the FLQA-w, the CWIS and the WWS are reliable, sensitive and valid instruments for the assessment of HRQoL in leg ulcers. However, they show differences in clinical feasibility and patient acceptance.

The impact of surgical site occurrences and the role of closed incision negative pressure therapy.

Surgical site occurrences are observed in up to 60% of inpatient surgical procedures in industrialised countries. The most relevant postoperative complication is surgical site infection (SSI) because of its impact on patient outcomes and enormous treatment costs. Literature reviews ('SSI', 'deep sternal wound infections' (DSWI), 'closed incision negative pressure wound therapy' (ciNPT) were performed by electronically searching MEDLINE (PubMed) and subsequently using a 'snowball' method of continued searches of the references in the identified publications. Search criteria included publications in all languages, various study types and publication in a peer-reviewed journal. The SSI literature search identified 1325, the DSWI search 590 and the ciNPT search 103 publications that fulfilled the search criteria. Patient-related SSI risk factors (diabetes mellitus, obesity, smoking, hypertension, female gender) and operation-related SSI risk factors (re-exploration, emergency operations, prolonged ventilation, prolonged operation duration) exist. We found that patient- and operation-related SSI risk factors were often different for each speciality and/or operative procedure. Based on the evidence, we found that high-risk incisions (sternotomy and incisions in extremities after high-energy open trauma) are principally recommended for ciNPT use. In 'lower'-risk incisions, the addition of patient-related or operation-related risk factors justifies the application of ciNPT.

Validation of the disease-specific quality of life Wuerzburg Wound Score in patients with chronic leg ulcer.

BACKGROUND: Aim of the study was to validate a newly developed disease-specific quality of life questionnaire (Wuerzburg Wound Score, WWS) in patients with chronic arterial or venous leg ulcers. PATIENTS AND METHODS: In this prospective study 115 patients with vascular disease associated leg ulcer (54 arterial ulcer, 61 venous ulcer) were studied (mean age 66 ± 11 years, 51 % male). All patients completed the WWS at baseline, and after four and 12 weeks. To assess construct validity additionally all patients completed the generic QoL-questionnaires Short Form-36 (SF-36) and Nottingham Health Profile (NHP). Construct validity and responsiveness of the WWS were tested. RESULTS: WWS showed acceptable construct validity versus SF-36 (r = 0.5 - 0.78; P < 0.001) and NHP (r = 0.36 - 0.68; P < 0.001). Responsiveness of the WWS was superior to SF-36 (P < 0.05) and NHP (P = 0.01). Generic as well as disease-specific QoL were more impaired in patients with arterial ulcer. CONCLUSIONS: The WWS is a valid measure of disease-specific QoL in patients with leg ulcers and it is more sensitive than the generic instruments in detecting changes of wound healing over time. Further assessment of the psychometric properties of the WWS with larger patient samples is required before the test can be recommended for use in clinical practice.

Improved gait parameters following surgical revascularization in patients with intermittent claudication.

Objective: Intermittent claudication (IC) is known to be associated with impaired gait parameters, with a higher incidence of falls and higher oxygen consumption due to uneconomic walking. However, the influence of arterial disobliteration in patients with IC on their gait pattern has rarely been investigated to date. The aim of this study was to examine the gait patterns before and after inflow revascularization by surgical disobliteration of pelvic and inguinal arteries (ie, common iliac artery, external iliac artery, common femoral artery, profound femoral artery, superficial femoral artery) in IC patients. Successful surgical disobliteration of inflow arteries (improvement of ankle brachial pressure index of ≥0.2 and patent common iliac, external iliac, common femoral, profound femoral, and superficial femoral arteries) is known to improve the painless walking distance for patients with IC due to peripheral arterial disease; however, its influence on gait parameters is unclear. We hypothesized that the gait parameters would also improve after surgery. Improved gait parameters can lead to a more economic walking process, lower oxygen consumption, a lower risk of falls, and a higher quality of life. Methods: In a single-center, exploratory, longitudinal study, we examined the gait parameters of 20 IC inpatients of our hospital before and after surgical disobliteration of pelvic and inguinal arteries. Spatiotemporal parameters such as range of motion of the hip and knee joint, stance phase, cadence, and foot rotation were obtained using the Diers 4Dmotion Lab (Diers International). The gait parameters were obtained under painful walking conditions preoperatively and with the patients walking pain free at the same speed postoperatively. Results: A total of 20 patients were examined. Surgical revascularization led to a higher walking cadence (mean, plus 7.88 steps; 95.5 steps/min vs 87.6 steps/min; P = .024), an increased range of motion of the hip joint (mean, plus 2.0°; 35.1° vs 33.1°; P = .038), and improved foot rotation (mean, plus 2.0°; 11.0° vs 9.0°; P = .02). Regarding other parameters such as step length, stance phase, and step duration, smaller differences were detected in this study. Conclusions: In this exploratory study, we found that surgical revascularization of pelvic and inguinal arteries in IC patients improved certain gait parameters. Further studies with larger patient numbers are needed to confirm these data and provide more evidence on this subject.

Changes of hematocrit and hemoglobin concentration in the cold Himalayan environment in dependence on total body fluid.

INTRODUCTION: The organism is exposed to a considerable hypoxic stress at high altitude, and the well-known polyglobulia is an effective strategy to sustain oxygen delivery to the tissue at reduced saturation of hemoglobin. In general, an increasing erythropoiesis is thought to be the reason, although this increase of red blood count can be observed after a short time of altitude exposure and the parameters are expressed as water-depending concentrations. Therefore, the influence of water distribution on hemoglobin (Hb) and hematocrit (Hct) values during a long-term exposure at high altitude was investigated. MATERIALS AND METHODS: Measurements were performed in 12 mountaineers before, during, and either 7/8 or 11/12 days after a Himalaya expedition (26-29 days at 4,850 to 7,600 m altitude). Arriving at 4,850 m an initial increase of Hb and Hct was followed by a short decrease during the first week and a continuous increase during the further stay. RESULTS: In maximum, 131.3% (Hb) and 117.4% (Hct) of the starting point were reached during the fourth week at altitude after the attempt to reach the summit of Broad Peak (8,047 m). Parallel the dehydration in the beginning turned to a hyperhydration at the end of the stay (D(2)O method). DISCUSSION: Erythropoietin rose only temporarily at altitude (max. +11 +1 mU/ml serum). Upon return, Hb and Hct normalized within a few days whereas hemoglobin mass (initially 881+ 44 g, CO-Hb method) was still increased by 13% (p < 0.01). CONCLUSION: In conclusion, a hemoconcentration effect (dehydration) is the reason of the initial peak of Hb and Hct. The further increase can only partially be explained by an absolute increase of Hb and Hct caused by stimulated erythropoiesis. A shift of intravasal fluid to the interstitial space is the other main reason of the observed changes in red blood count.

Auto-PEEP in the therapy of AMS in one person at 4,330 m.

BACKGROUND: The human organism is exposed to considerable hypoxic stress at high altitudes. Our intention was to investigate if a special breathing pattern with expiration against the resistance of pursed lips leads to an elevation in oxygen saturation (SaO(2)). For the first time ever, oxygen saturation was measured continuously during the initial situation, during self-performed positive end-expiratory pressure breathing (auto-PEEP) itself, and during observation afterwards. MATERIALS AND METHODS: The investigation was performed on a 33-year-old male suffering from high-altitude illness (Lake Louise Score, 9) after a 4-day rapid ascent from 350 m to 4,330 m during an expedition to Mount McKinley (6,198 m). SaO(2) was measured continuously at 4-s intervals. After a rest of 1.5 h in a dorsal recumbent position with a slightly elevated (about 15 degrees ) upper body, the patient used a wristwatch to breathe according to a special time pattern (inspiration 2 s, expiration 8 s against the resistance of pursed lips). After 30 min, breathing was then allowed without any restrictions, and the inspiration/expiration ratio was approximately 1:1. RESULTS: There was a relatively sharp rise in SaO(2) from an average of 62% to 85% within only 5 min after auto-PEEP began. This was followed by a comparable rise to values of 95% at the end of the auto-PEEP period. During normal breathing, SaO(2) decreased slowly within half an hour to values of about 70% and remained at this level. The person reported relief in symptoms and no exhaustion. Vertigo-an indication of hypocapnia caused by hyperventilation-was not observed. DISCUSSION: The 30% rise in SaO(2) and the improved saturation level after auto-PEEP are remarkable. Elevated intra-thoracal pressure may lead to a reopening of collapsed alveoli in addition to an improved gradient of alveolar-capillary pressure. In addition, a pressure-induced displacement of interstitial fluid resulting in a reduced diffusion distance may lead to improved alveolar-capillary diffusion. This would explain the slower rise in SaO(2) after 10 min of auto-PEEP and the elevated level of SaO(2) compared to the initial level before auto-PEEP. CONCLUSION: As a result of the substantial and lasting improvement in SaO(2) in combination with relief in AMS symptoms and its easy use, auto-PEEP (30 min every 2 h) can be a useful therapy option in the event of high-altitude-induced hypoxia and AMS.

Testing individual risk of acute mountain sickness at greater altitudes.

The assessment of an individual's degree of acclimatization to altitude is difficult. This is particularly applicable to military operations that have to be performed at altitude. This study describes a new and simple test that allows for the determination of an individual's risk for high-altitude illness at higher altitudes. The prediction is based on the lowest oxygen saturation (SaO2) found during an uphill run at high altitude (11,060 ft [3,371 m]), combined with the time needed to complete the run. The test results were compared against the severity of high-altitude symptomatology on the summit of Mont Blanc (15,762 ft [4,808 m]). The main outcome was the significant correlation between time as well as SaO2 and the severity of high-altitude symptomatology on the summit of Mont Blanc. The newly developed performance test allows, at a "safe" altitude, the prediction of an individual's risk of developing high altitude illness if they continue to ascend. It allows the determination of the best acclimatized subjects within a group, for example, before a military mission at greater altitude.

High Temperature Mechanical Properties of High Strength Structural Steels Q550, Q690 and Q890.

This paper reports the results of an experimental study on high temperature mechanical properties of high strength structural steel (HSSS) produced in accordance with Chinese materials standards. Steady-state tensile coupon tests were carried out on specimens made of China grade steels of Q550, Q690 and Q890. Nine elevated temperature levels up to 800 °C were considered. The elastic modulus, yield strength, ultimate strength and ultimate strain were derived from the measured stress-strain curves. A model was developed to predict the high temperature properties of these steels using an approach developed by the National Institute of Standards and Technology (NIST) and by calibrating the model parameters to the test data. The test results are compared to other tests on high strength steels reported in literature. The test results are also compared to predictions of high temperature properties from various building codes and other standards. The study found that steel grade has significant effect on the reduction factors. The difference between the reduction factors of elastic modulus for Q690 and Q550 was 30% at 600 °C. In this study, reduction factor is defined as the ratio of the high temperature property to the corresponding room temperature property. The study also found that the material models in current codes are not applicable to the investigated high strength steels.

Improvement in altitude performance test after further acclimatization in pre-acclimatized soldiers.

The Altitude Performance Test is a measure designed to assess an individual's degree of acclimatization to reduce the risk of acute mountain sickness during high-altitude activities. The aim of this study was to investigate the hypothesis that test results will improve in pre-acclimatized soldiers after several days of further acclimatization. The Altitude Performance Test consists of an uphill run at high altitude. The event is timed and performed with continuous oxygen saturation (SpO2) monitoring. The individual's time and lowest SpO2 measurement are recorded. This test was performed on the first day of arriving at 11,060 ft, and after 9 days at the same location. The 37 male soldiers were all pre-acclimatized before arrival. The sleeping altitude remained constant at 11,060 ft, and the daytime altitudes increased up to a maximum of 15,775 ft. Test results improved significantly after a further 9 days of acclimatization (time, -11 s; SpO2, +5%-points; p ≤ 0.001). This is remarkable because all soldiers were pre-acclimatized and showed only minor acute mountain sickness symptoms during the entire stay. This indicates that the acclimatization process is not finished after amelioration of altitude symptoms. The demonstrated improvement in physical performance could prove very important, particularly during military missions performed at high altitude.

Richard von Volkmann: surgeon and Renaissance man.

Richard von Volkmann (1830-1889), one of the most important surgeons of the 19(th) century, is regarded as one of the fathers of orthopaedic surgery. He was a contemporary of Langenbeck, Esmarch, Lister, Billroth, Kocher, and Trendelenburg. He was head of the Department of Surgery at the University of Halle, Germany (1867-1889). His popularity attracted doctors and patients from all over the world. He was the lead physician for the German military during two wars. From this experience, he compared the mortality of civilian and war injuries and investigated the general poor hygienic conditions in civilian hospitals. This led him to introduce the "antiseptic technique" to Germany that was developed by Lister. His powers of observation and creativity led him to findings and achievements that to this day bear his name: Volkmann's contracture and the Hueter-Volkmann law. Additionally, he was a gifted writer; he published not only scientific literature but also books of children's fairy tales and poems under the pen name of Richard Leander, assuring him a permanent place in the world of literature as well as orthopaedics.

Literature on the Subject of Vacuum Therapy Review and Update.

INTRODUCTION: Today, vacuum therapy can be regarded as established in routine clinical use. Many hundreds of reports on the subject of vacuum therapy have appeared in medical literature. This review intends to give an overview of the peer-reviewed literature published to date and its quality considering criteria of evidence-based medicine (EbM). METHODS: Literature search (MEDLINE, EMBASE, Cochrane, extensive manual search); up to May 31, 2006; evidence level: Classification of the Oxford Centre for Evidence-based Medicine. RESULTS: Five hundred and fifty peer-reviewed citations were identified. Impressive jump in the annual publication rate is found from the year 2000 onwards; continuous broadening of the fields of indications; over 85% of all reports are case reports/series (only n = 27; EbM level < 4). To date, most of the publications are by authors from the United States, Germany, United Kingdom, Austria, the Netherlands, Switzerland, France, and Sweden. 7.5% of all peer-reviewed articles investigate scientific back grounds. DISCUSSION: The clinical significance of this therapy is underlined by an obviously continuously marked extension of the range of indications in all surgical fields, and even in extreme ages of the patients. There is a considerable deficit of basic pathophysiological research and well-designed studies. This "deficiency," however, when judged against the quality of the general medical literature, does not point to the poor efficacy or low benefit of vacuum therapy but should rather be seen as a symptom of the clinical practitioner's problems in dealing with modern aspects of the theoretical background of EbM.