Residual Popliteal Aneurysm Perfusion Leading to Embolic Complications: A Case Report.

Introduction: Surgical management of popliteal artery aneurysms has been described for half a century. Long term development of the excluded aneurysm sac in the popliteal segment however remains widely unknown, with only a few small series describing outcomes. Residual aneurysm perfusion has the potential to lead to serious complications. Report: A 63 year old man presents with skin and soft tissue necrosis of the right calf two years after proximal and distal aneurysm ligation and great saphenous vein bypass for a popliteal artery aneurysm. Computed tomography and magnetic resonance angiography show perfusion of the excluded aneurysm as well as extensive necrosis of the gastrocnemius muscle. Direct angiography of the aneurysm demonstrated retrograde aneurysm perfusion due to insufficient distal ligation with recurrent micro-embolisation to the calf via geniculate arteries. Coiling of the geniculate arteries was performed, plugging the connection to the tibiofibular trunk and embolisation of the aneurysm sac. After the intervention, no flow was seen in the aneurysm sac and the patient made full recovery. Discussion: Residual aneurysm sac perfusion can lead to complications long after successful aneurysm exclusion. Follow-up after surgery of popliteal aneurysms should include observation of the excluded aneurysm sac with control of residual blood flow. For persistent sac perfusion, aneurysm enlargement or symptoms, further treatment should be considered. Surgical aspects such as complete transection of the artery after aneurysm ligation or end to end anastomosis of the bypass may be considered, to prevent such complications.

Peri-operative Mortality and Morbidity of Complex Abdominal Aortic Aneurysms Repair in Switzerland: A Swissvasc Report.

OBJECTIVE: Complex abdominal aortic aneurysms (cAAA) pose a clinical challenge. The aim of this study was to assess the 30 day mortality and morbidity for open aneurysm repair (OAR) and fenestrated/branched endovascular aortic repair (F/BEVAR), and the effect of hospital volume in patients with asymptomatic cAAA in Switzerland. METHODS: Retrospective, cohort study using data from Switzerland's national registry for vascular surgery, Swissvasc, including patients treated from 1 January 2019 to 31 December 2022. All patients with asymptomatic, true, non-infected cAAA were identified. Primary outcome was 30 day mortality and morbidity reported using the Clavien-Dindo classification. Outcomes were compared between OAR and F/BEVAR after propensity score weighting. RESULTS: Of the 461 patients identified, 333 underwent OAR and 128 underwent F/BEVAR for cAAA. At 30 days, overall mortality rate was 3.3% after OAR and 3.1% after F/BEVAR (p = .76). Propensity scores weighted analysis indicated similar morbidity rates for both approaches: F/BEVAR (OR 0.69, 95% CI 0.45 - 1.05, p = .055); intestinal ischaemia (1.8% after OAR, 3.1% after F/BEVAR, p = .47) and renal failure requiring dialysis (1.5% after OAR, 5.5% after F/BEVAR, p = .024) were associated with highest morbidity and mortality. Treatment specific complications with high morbidity were abdominal compartment syndrome and lower limb compartment syndrome following F/BEVAR. Overall treatment volume was low for most of the hospitals treating cAAA in Switzerland; outliers with increased mortality were identified among low volume hospitals. CONCLUSION: Comparable 30 day mortality and morbidity rates were found between OAR and F/BEVAR for cAAA in Switzerland; lack of centralisation was also highlighted. Organ specific complications driving mortality were renal failure, intestinal ischaemia, and limb ischaemia, specifically after F/BEVAR. Treatment in specialised high volume centres, alongside efforts to reduce peri procedural kidney injury and mesenteric ischaemia, offers potential to lower morbidity and mortality in elective cAAA treatment.

Indication and Outcome of Late Open Conversion after Abdominal Endovascular Aortic Repair.

BACKGROUND: Endovascular aortic repair (EVAR) has become the standard of care for patients with infrarenal aortic aneurysms over the last 2 decades. Endograft technology and treatment of complications like endoleaks, graft migration, or graft occlusion developed over time. However, sometimes open surgical conversion maybe required. Our aim was to analyze the indications, the technical aspects and outcomes in patients who underwent open conversion after EVAR with different types and generations of endografts. METHODS: This retrospective single-center study reviewed all patients who underwent EVAR from 2004 to 2020. Open surgical conversions >1 month post EVAR were identified. Conversions for graft infection were excluded. Indications for conversion and operative technique were analyzed. Primary endpoint of the study was 30-day mortality. Secondary endpoints were re-interventions and follow-up mortality. RESULTS: During 2004 and 2020, 443 consecutive EVARs were performed, and 28 patients required open surgical conversion, with an additional 3 referred from other hospitals (N = 31). The median age was 75 (range 58-93); 94% were male. Conversion was performed after a median time of 55 months (range 16-209). Twenty patients underwent elective and 11 emergency conversion. Indications for open conversion were graft migration, respectively, disease progression with endoleak type Ia and/or Ib in 52% (16/31) and sac expansion due to endoleak type II in 26% (8/31). Of the 31 patients, 17 (55%) had at least one previous endovascular re-intervention. All patients met the device-specific instructions for use for each implanted endograft. In-hospital intervention rate was 16% (5/31). Thirty-day mortality rate was 3% (1/31) with one patient died due to multiorgan failure after rupture with complete endograft replacement. Five patients (16%) died during follow-up. Mid-term follow-up was 47.5 months (range 24-203) with estimated cumulative survival rates of 97%, 89%, and 84%, at 1, 3, and 5 years, respectively. CONCLUSIONS: Late open conversion remains a valuable treatment option and can be performed safely in elective and emergency setting with a low early mortality. Lifelong surveillance and prompt intervention when necessary are essential in ensuring optimal outcomes after EVAR and preventing the need for emergent conversions.

Physician Made Bovine Pericardial Tube Grafts in Aortic Infection: A European Multicentre Study.

OBJECTIVE: This study examines outcome and durability of physician made bovine pericardial tube grafts in aortic infections in all anatomical locations. METHODS: This was a retrospective and prospective international multicentre study. Peri-operative and long term outcomes of patients undergoing in situ aortic reconstruction for native or graft infections with physician made bovine pericardial tube grafts between January 2008 and December 2020 in four European tertiary referral centres were analysed. The primary endpoint was recurrent aortic infection. Secondary endpoints were persistent infection, aortic re-operation for infection, graft related complications, and death. RESULTS: One hundred and sixty eight patients (77% male, mean age 67 ± 11 years) were identified: 38 (23%) with native and 130 (77%) with aortic graft infection. The thirty day mortality rate was 15% (n = 26) overall, 11% (n = 4), and 17% (n = 22) for native and aortic graft infections, respectively (p = .45). Median follow up was 26 months (interquartile range [IQR] 10, 51). Estimated survival at one, two, three, and five years was 64%, 60%, 57%, and 50%, and significantly better for native (81%, 77%, 77%, and 69%) than for graft infections (58%, 55%, 51%, and 44%; p = .011). Nine patients (5.3%) had persistent infection and 10 patients (6%) had aortic re-infection after a median of 10 months (IQR 5, 22), resulting in an estimated freedom from re-infection at one, two, three, and five years of 94%, 92%, 90%, and 86%. Estimated freedom from graft complications at one, two, three, and five years was 91%, 89%, 87%, and 87%. CONCLUSION: This multicentre study demonstrates low re-infection rates when using physician made bovine pericardial tube grafts, comparable to those of other biological grafts. The rate of graft complications, mainly anastomotic aneurysms and stenoses, was low, while graft degeneration was absent. Physician made bovine pericardial tube grafts are an excellent tool for in situ reconstruction in the setting of native aortic infection or aortic graft infection.

Infective Native Aortic Aneurysm: a Delphi Consensus Document on Treatment, Follow Up, and Definition of Cure.

OBJECTIVE: Evidence is lacking to guide the management of infective native aortic aneurysm (INAA). The aim of this study was to establish expert consensus on surgical and antimicrobial treatment and follow up, and to define when an INAA is considered cured. METHODS: Delphi methodology was used. The principal investigators invited 47 international experts (specialists in infectious diseases, radiology, nuclear medicine, and vascular and cardiothoracic surgery) via email. Four Delphi rounds were performed, three weeks each, using an online questionnaire with initially 28 statements. The panellists rated the statements on a five point Likert scale. Comments on statements were analysed, statements were revised and added or deleted, and the results were presented in the iterative rounds. Consensus was defined as ≥ 75% of the panel rating a statement as strongly agree or agree on the Likert scale, and consensus on the final assessment was defined as Cronbach's alpha > 0.80. RESULTS: All 49 panellists completed all four rounds, resulting in 100% participation. One statement was added based on the results and comments of the panel, resulting in 29 final statements: three on need for consensus, 20 on treatment, five on follow up, and one on definition of cure. All 29 statements reached agreement of ≥ 86%. Cronbach's alpha increased for each consecutive round; round 1, 0.85; round 2, 0.90; round 3, 0.91; and round 4, 0.94. Thus, consensus was reached for all statements. CONCLUSION: INAAs are rare, and high level evidence to guide optimal management is lacking. This consensus document was established with the aim of helping clinicians manage these challenging patients, as a supplement to current guidelines. The presented consensus will need future amendments in accordance with newly acquired knowledge.

The value of saccade metrics and VOR gain in detecting a vestibular stroke.

OBJECTIVE: A normal video Head Impulse Test is the gold standard in the emergency department to rule-in patients with an acute vestibular syndrome and a stroke. We aimed to compare the diagnostic accuracy of vHIT metrics regarding the vestibulo-ocular reflex gain and the corrective saccades in detecting vestibular strokes. METHODS: Prospective cross-sectional study (convenience sample) of patients presenting with acute vestibular syndrome in the emergency department of a tertiary referral centre between February 2015 and May 2020. We screened 1677 patients and enrolled 76 patients fulfilling the inclusion criteria of acute vestibular syndrome. All patients underwent video head impulse test with automated and manual data analysis. A delayed MRI served as a gold standard for vestibular stroke confirmation. RESULTS: Out of 76 patients, 52 were diagnosed with acute unilateral vestibulopathy and 24 with vestibular strokes. The overall accuracy of detecting stroke with an automated vestibulo-ocular reflex gain was 86.8%, compared to 77.6% for cumulative saccade amplitude and automatic saccade mean peak velocity measured by an expert and 71% for cumulative saccade amplitude and saccade mean peak velocity measured automatically. Gain misclassified 13.1% of the patients as false positive or false negative, manual cumulative saccade amplitude and saccade mean peak velocity 22.3%, and automated cumulative saccade amplitude and saccade mean peak velocity 28.9% respectively. CONCLUSIONS: We found a better accuracy of video head impulse test for the diagnosis of vestibular strokes when using the vestibulo-ocular reflex gain than using saccade metrics. Nevertheless, saccades provide an additional and important information for video head impulse test evaluation. The automated saccade detection algorithm is not yet perfect compared to expert analysis, but it may become a valuable tool for future non-expert video head impulse test evaluations.

Practice of neuromonitoring in open and endovascular thoracoabdominal aortic repair-an international expert-based modified Delphi consensus study.

OBJECTIVES: Spinal cord injury is detrimental for patients undergoing open or endovascular thoracoabdominal aortic aneurysm (TAAA) repair. The aim of this survey and of the modified Delphi consensus was to gather information on current practices and standards in neuroprotection in patients undergoing open and endovascular TAAA. METHODS: The Aortic Association conducted an international online survey on neuromonitoring in open and endovascular TAAA repair. In a first round an expert panel put together a survey on different aspects of neuromonitoring. Based on the answers from the first round of the survey, 18 Delphi consensus questions were formulated. RESULTS: A total of 56 physicians completed the survey. Of these, 45 perform open and endovascular TAAA repair, 3 do open TAAA repair and 8 do endovascular TAAA repair. At least 1 neuromonitoring or protection modality is utilized during open TAAA surgery. Cerebrospinal fluid (CSF) drainage was used in 97.9%, near infrared spectroscopy in 70.8% and motor evoked potentials or somatosensory evoked potentials in 60.4%. Three of 53 centres do not utilize any form of neuromonitoring or protection during endovascular TAAA repair: 92.5% use CSF drainage; 35.8%, cerebral or paravertebral near infrared spectroscopy; and 24.5% motor evoked potentials or somatosensory evoked potentials. The utilization of CSF drainage and neuromonitoring varies depending on the extent of the TAAA repair. CONCLUSIONS: The results of this survey and of the Delphi consensus show that there is broad consensus on the importance of protecting the spinal cord to avoid spinal cord injury in patients undergoing open TAAA repair. Those measures are less frequently utilized in patients undergoing endovascular TAAA repair but should be considered, especially in patients who require extensive coverage of the thoracoabdominal aorta.

Measuring the Influence of Magnetic Vestibular Stimulation on Nystagmus, Self-Motion Perception, and Cognitive Performance in a 7T MRT.

Strong magnetic fields induce dizziness, vertigo, and nystagmus due to Lorentz forces acting on the cupula in the semi-circular canals, an effect called magnetic vestibular stimulation (MVS). In this article, we present an experimental setup in a 7T MRT scanner (MRI scanner) that allows the investigation of the influence of strong magnetic fields on nystagmus as well as perceptual and cognitive responses. The strength of MVS is manipulated by altering the head positions of the participants. The orientation of the participants' semicircular canals with respect to the static magnetic field is assessed by combining a 3D magnetometer and 3D constructive interference in steady-state (3D-CISS) images. This approach allows to account for intra- and inter-individual differences in participants' responses to MVS. In the future, MVS can be useful for clinical research, for example, in the investigation of compensatory processes in vestibular disorders. Furthermore, it could foster insights into the interplay between vestibular information and cognitive processes in terms of spatial cognition and the emergence of self-motion percepts under conflicting sensory information. In fMRI studies, MVS can elicit a possible confounding effect, especially in tasks influenced by vestibular information or in studies comparing vestibular patients with healthy controls.

Editor's Choice - Infective Native Aortic Aneurysms: A Delphi Consensus Document on Terminology, Definition, Classification, Diagnosis, and Reporting Standards.

OBJECTIVE: There is no consensus regarding the terminology, definition, classification, diagnostic criteria, and algorithm, or reporting standards for the disease of infective native aortic aneurysm (INAA), previously known as mycotic aneurysm. The aim of this study was to establish this by performing a consensus study. METHODS: The Delphi methodology was used. Thirty-seven international experts were invited via mail to participate. Four two week Delphi rounds were performed, using an online questionnaire, initially with 22 statements and nine reporting items. The panellists rated the statements on a five point Likert scale. Comments on statements were analysed, statements revised, and results presented in iterative rounds. Consensus was defined as ≥ 75% of the panel selecting "strongly agree" or "agree" on the Likert scale, and consensus on the final assessment was defined as Cronbach's alpha coefficient > .80. RESULTS: All 38 panellists completed all four rounds, resulting in 100% participation and agreement that this study was necessary, and the term INAA was agreed to be optimal. Three more statements were added based on the results and comments of the panel, resulting in a final 25 statements and nine reporting items. All 25 statements reached an agreement of ≥ 87%, and all nine reporting items reached an agreement of 100%. The Cronbach's alpha increased for each consecutive round (round 1 = .84, round 2 = .87, round 3 = .90, and round 4 = .92). Thus, consensus was reached for all statements and reporting items. CONCLUSION: This Delphi study established the first consensus document on INAA regarding terminology, definition, classification, diagnostic criteria, and algorithm, as well as reporting standards. The results of this study create essential conditions for scientific research on this disease. The presented consensus will need future amendments in accordance with newly acquired knowledge.

Artificial intelligence for early stroke diagnosis in acute vestibular syndrome.

Objective: Measuring the Vestibular-Ocular-Reflex (VOR) gains with the video head impulse test (vHIT) allows for accurate discrimination between peripheral and central causes of acute vestibular syndrome (AVS). In this study, we sought to investigate whether the accuracy of artificial intelligence (AI) based vestibular stroke classification applied in unprocessed vHIT data is comparable to VOR gain classification. Methods: We performed a prospective study from July 2015 until April 2020 on all patients presenting at the emergency department (ED) with signs of an AVS. The patients underwent vHIT followed by a delayed MRI, which served as a gold standard for stroke confirmation. The MRI ground truth labels were then applied to train a recurrent neural network (long short-term memory architecture) that used eye- and head velocity time series extracted from the vHIT examinations. Results: We assessed 57 AVS patients, 39 acute unilateral vestibulopathy patients (AUVP) and 18 stroke patients. The overall sensitivity, specificity and accuracy for detecting stroke with a VOR gain cut-off of 0.57 was 88.8, 92.3, and 91.2%, respectively. The trained neural network was able to classify strokes with a sensitivity of 87.7%, a specificity of 88.4%, and an accuracy of 87.9% based on the unprocessed vHIT data. The accuracy of these two methods was not significantly different (p = 0.09). Conclusion: AI can accurately diagnose a vestibular stroke by using unprocessed vHIT time series. The quantification of eye- and head movements with the use of machine learning and AI can serve in the future for an automated diagnosis in ED patients with acute dizziness. The application of different neural network architectures can potentially further improve performance and enable direct inference from raw video recordings.

Influence of Soldiers' Cardiorespiratory Fitness on Physiological Responses and Dropouts During a Loaded Long-distance March.

INTRODUCTION: In military service, marching is an important, common, and physically demanding task. Minimizing dropouts, maintaining operational readiness during the march, and achieving a fast recovery are desirable because the soldiers have to be ready for duty, sometimes shortly after an exhausting task. The present field study investigated the influence of the soldiers' cardiorespiratory fitness on physiological responses during a long-lasting and challenging 34 km march. MATERIALS AND METHODS: Heart rate (HR), body core temperature (BCT), total energy expenditure (TEE), energy intake, motivation, and pain sensation were investigated in 44 soldiers (20.3 ± 1.3 years, 178.5 ± 7.0 cm, 74.8 ± 9.8 kg, body mass index: 23.4 ± 2.7 kg × m-2, peak oxygen uptake ($\dot{\rm{V}}$O2peak): 54.2 ± 7.9 mL × kg-1 × min-1) during almost 8 hours of marching. All soldiers were equipped with a portable electrocardiogram to record HR and an accelerometer on the hip, all swallowed a telemetry pill to record BCT, and all filled out a pre- and post-march questionnaire. The influence of aerobic capacity on the physiological responses during the march was examined by dividing the soldiers into three fitness groups according to their $\dot{\rm{V}}$O2peak. RESULTS: The group with the lowest aerobic capacity ($\dot{\rm{V}}$O2peak: 44.9 ± 4.8 mL × kg-1 × min-1) compared to the group with the highest aerobic capacity ($\dot{\rm{V}}$O2peak: 61.7 ± 2.2 mL × kg-1 × min-1) showed a significantly higher (P < .05) mean HR (133 ± 9 bpm and 125 ± 8 bpm, respectively) as well as peak BCT (38.6 ± 0.3 and 38.4 ± 0.2 °C, respectively) during the march. In terms of recovery ability during the break, no significant differences could be identified between the three groups in either HR or BCT. The energy deficit during the march was remarkably high, as the soldiers could only replace 22%, 26%, and 36% of the total energy expenditure in the lower, middle, and higher fitness group, respectively. The cardiorespiratory fittest soldiers showed a significantly higher motivation to perform when compared to the least cardiorespiratory fit soldiers (P = .002; scale from 1 [not at all] to 10 [extremely]; scale difference of 2.3). A total of nine soldiers (16%) had to end marching early: four soldiers (21%) in the group with the lowest aerobic capacity, five (28%) in the middle group, and none in the highest group. CONCLUSION: Soldiers with a high $\dot{\rm{V}}$O2peak showed a lower mean HR and peak BCT throughout the long-distance march, as well as higher performance motivation, no dropouts, and lower energy deficit. All soldiers showed an enormous energy deficit; therefore, corresponding nutritional strategies are recommended.

Eyeblink Detection in the Field: A Proof of Concept Study of Two Mobile Optical Eye-Trackers.

INTRODUCTION: High physical and cognitive strain, high pressure, and sleep deficit are part of daily life for military professionals and civilians working in physiologically demanding environments. As a result, cognitive and physical capacities decline and the risk of illness, injury, or accidents increases. Such unfortunate outcomes could be prevented by tracking real-time physiological information, revealing individuals' objective fatigue levels. Oculometrics, and especially eyeblinks, have been shown to be promising biomarkers that reflect fatigue development. Head-mounted optical eye-trackers are a common method to monitor these oculometrics. However, studies measuring eyeblink detection in real-life settings have been lacking in the literature. Therefore, this study aims to validate two current mobile optical eye-trackers in an unrestrained military training environment. MATERIALS AND METHOD: Three male participants (age 20.0 ± 1.0) of the Swiss Armed Forces participated in this study by wearing three optical eye-trackers, two VPS16s (Viewpointsystem GmbH, Vienna, Austria) and one Pupil Core (Pupil Labs GmbH, Berlin, Germany), during four military training events: Healthcare education, orienteering, shooting, and military marching. Software outputs were analyzed against a visual inspection (VI) of the video recordings of participants' eyes via the respective software. Absolute and relative blink numbers were provided. Each blink detected by the software was classified as a "true blink" (TB) when it occurred in the software output and the VI at the same time, as a "false blink" (FB) when it occurred in the software but not in the VI, and as a "missed blink" (MB) when the software failed to detect a blink that occurred in the VI. The FBs were further examined for causes of the incorrect recordings, and they were divided into four categories: "sunlight," "movements," "lost pupil," and "double-counted". Blink frequency (i.e., blinks per minute) was also analyzed. RESULTS: Overall, 49.3% and 72.5% of registered eyeblinks were classified as TBs for the VPS16 and Pupil Core, respectively. The VPS16 recorded 50.7% of FBs and accounted for 8.5% of MBs, while the Pupil Core recorded 27.5% of FBs and accounted for 55.5% of MBs. The majority of FBs-45.5% and 73.9% for the VPS16 and Pupil Core, respectively-were erroneously recorded due to participants' eye movements while looking up, down, or to one side. For blink frequency analysis, systematic biases (±limits of agreement) stood at 23.3 (±43.5) and -4.87 (±14.1) blinks per minute for the VPS16 and Pupil Core, respectively. Significant differences in systematic bias between devices and the respective VIs were found for nearly all activities (P < .05). CONCLUSION: An objective physiological monitoring of fatigue is necessary for soldiers as well as civil professionals who are exposed to higher risks when their cognitive or physical capacities weaken. However, optical eye-trackers' accuracy has not been specified under field conditions-especially not in monitoring fatigue. The significant overestimation and underestimation of the VPS16 and Pupil Core, respectively, demonstrate the general difficulty of blink detection in the field.

Peripheral Artery Disease Leading to Major Amputation: Trends in Revascularization and Mortality Over 18 Years.

BACKGROUND: Patients with peripheral artery disease (PAD) are at risk for amputation. The aim of this study was to assess the type of revascularization prior to and the 30-day mortality rate after major amputation due to PAD. METHODS: Retrospective analysis of consecutive patients undergoing major amputation for PAD between 01/2000 and 12/2017 at a tertiary referral center. The number and target level of ipsilateral revascularizations prior to amputation were analyzed per patient and over the years. There were 3 types of revascularization (open, endovascular and combined treatment) at 3 levels: aortoiliac, femoropopliteal and infrapopliteal. Univariate and multivariate logistic regression models were used to assess the association of level of amputation and patient characteristics with 30-day mortality. RESULTS: A total of 312 patients (65.7% male) with a mean age of 73.3 ± 11 years underwent 338 major amputations: 70 (21%) above/through knee and 268 (79%) below knee. A median of 2 (interquartile range, IQR 1-4) revascularizations were performed prior to amputation, with a slight decrease of 1.4% per year from 2000-2017 (incidence rate ratio of 0.986 0.974-0.998; Poisson regression analysis, P = 0.021). 16% (53/338) of patients underwent primary amputation without revascularization; this number remained relatively stable throughout the study period. The proportion of exclusively open treatment before amputation decreased substantially from 35% in 2006 to none in 2016, while exclusively endovascular revascularizations were performed increasingly from 17% in 2002 to 64% in 2016. Amputation occurred after a median of 9.5 months (IQR 0.9-67.6 months) if the first revascularization was aortoiliac or femoropopliteal and after 2.1 months (IQR 0.5-13.8 months) if the first intervention was infrapopliteal (P < 0.001) with no significant change over the years (normal linear regression, P= 0.887). Thirty-day mortality was 8.9% (22/247) after below knee and 27.7% (18/65) after above/through knee amputation (adjusted OR 3.84, 95% CI 1.74-8.54, P= 0.001) with a slight increase of mortality over the study period (adjusted OR 1.09, 95% CI 1.018-1.159, Poisson regression analysis, P= 0.021). The uni- and multivariate analysis of patient characteristics did not show an association with mortality, except higher ASA classification (adjusted OR 2.65, 95% CI 1.23-5.72, P= 0.012). CONCLUSIONS: Mortality, especially after above/through knee amputation, remains high over the past 2 decades. There is a clear shift towards endovascular treatment of patients with PAD prior to major amputation. In patients needing infrapopliteal revascularizations, amputation was performed much sooner than in those with aortoiliac or femoropopliteal interventions, with no improvement over the years. Strategies to extend limb salvage in these patients should be the focus of further research.

Detecting Soldiers' Fatigue Using Eye-Tracking Glasses: Practical Field Applications and Research Opportunities.

INTRODUCTION: Objectively determining soldiers' fatigue levels could help prevent injuries or accidents resulting from inattention or decreased alertness. Eye-tracking technologies, such as optical eye tracking (OET) and electrooculography (EOG), are often used to monitor fatigue. Eyeblinks-especially blink frequency and blink duration-are known as easily observable and valid biomarkers of fatigue. Currently, various eye trackers (i.e., eye-tracking glasses) are available on the market using either OET or EOG technologies. These wearable eye trackers offer several advantages, including unobtrusive functionality, practicality, and low costs. However, several challenges and limitations must be considered when implementing these technologies in the field to monitor fatigue levels. This review investigates the feasibility of eye tracking in the field focusing on the practical applications in military operational environments. MATERIALS AND METHOD: This paper summarizes the existing literature about eyeblink dynamics and available wearable eye-tracking technologies, exposing challenges and limitations, as well as discussing practical recommendations on how to improve the feasibility of eye tracking in the field. RESULTS: So far, no eye-tracking glasses can be recommended for use in a demanding work environment. First, eyeblink dynamics are influenced by multiple factors; therefore, environments, situations, and individual behavior must be taken into account. Second, the glasses' placement, sunlight, facial or body movements, vibrations, and sweat can drastically decrease measurement accuracy. The placement of the eye cameras for the OET and the placement of the electrodes for the EOG must be chosen consciously, the sampling rate must be minimal 200 Hz, and software and hardware must be robust to resist any factors influencing eye tracking. CONCLUSION: Monitoring physiological and psychological readiness of soldiers, as well as other civil professionals that face higher risks when their attention is impaired or reduced, is necessary. However, improvements to eye-tracking devices' hardware, calibration method, sampling rate, and algorithm are needed in order to accurately monitor fatigue levels in the field.

Validation of ambulatory monitoring devices to measure energy expenditure and heart rate in a military setting.

Objectives.To investigate the validity of different devices and algorithms used in military organizations worldwide to assess physical activity energy expenditure (PAEE) and heart rate (HR) among soldiers.Design.Device validation study.Methods. Twenty-three male participants serving their mandatory military service accomplished, firstly, nine different military specific activities indoors, and secondly, a normal military routine outdoors. Participants wore simultaneously an ActiHeart, Everion, MetaMax 3B, Garmin Fenix 3, Hidalgo EQ02, and PADIS 2.0 system. The PAEE and HR data of each system were compared to the criterion measures MetaMax 3B and Hidalgo EQ02, respectively.Results. Overall, the recorded systematic errors in PAEE estimation ranged from 0.1 (±1.8) kcal.min-1to -1.7 (±1.8) kcal.min-1for the systems PADIS 2.0 and Hidalgo EQ02 running the Royal Dutch Army algorithm, respectively, and in the HR assessment ranged from -0.1 (±2.1) b.min-1to 0.8 (±3.0) b.min-1for the PADIS 2.0 and ActiHeart systems, respectively. The mean absolute percentage error (MAPE) in PAEE estimation ranged from 29.9% to 75.1%, with only the Everion system showing an overall MAPE <30%, but all investigated devices reported overall MAPE <1.4% in the HR assessment.Conclusions. The present study demonstrated poor to moderate validity in terms of PAEE estimation, but excellent validity in all investigated devices in terms of HR assessment. Overall, the Everion performed among the best in both parameters and with a device placement on the upper arm, the Everion system is particularly useful during military service, as it does not interfere with other relevant equipment.

Current trends in reduction or elimination of the aortic impulse during stent-graft deployment and balloon moulding during thoracic endovascular aortic repair.

OBJECTIVES: A survey was performed to evaluate the methods used for reduction or elimination of the aortic impulse (REAI) to facilitate precise stent graft placement and balloon moulding during thoracic endovascular aortic repair (TEVAR). METHODS: A total of 127 physicians (1 per hospital) were contacted and asked to fill out a short, comprehensive questionnaire on an internet-based platform. RESULTS: Fifty physicians (39.4%) responded and completed the survey. Routine use of REAI for stent graft deployment is most frequently used in the ascending aorta and less frequently in the aortic arch and the descending aorta (86.4% vs 69.4% vs 56%). Some physicians based the decision of whether to use REAI on the type of stent graft in the respective location (13.6% vs 24.5% vs 24.0%). Stent-graft deployment without REAI, irrespective of the type of stent graft used, was never done in the ascending aorta (0.0%), in 3 centres in the aortic arch (6.1%) and in 10 centres in the descending aorta (20%). The REAI method most frequently used was dependent on the aortic segment (ascending aorta vs aortic arch vs descending aorta) rapid right ventricular pacing (90.9% vs 59.2% vs 28.0%), followed by pharmacological blood pressure reduction (13.6% vs 53.1% vs 64.0%) and venous inflow occlusion (13.6% vs 14.3% vs 4.0%), respectively. Tip capture and non-occlusive deployment systems were frequently quoted as reasons for not using REAI. CONCLUSIONS: REAI is the fundament for TEVAR in all thoracic aortic segments, with a decline in usage from proximal (ascending) to distal (descending). Rapid right ventricular pacing is the preferred REAI method used in TEVAR. Most procedures are performed with the patient under general anaesthesia. The types of stent grafts and moulding balloons used have an impact on the use or non-use of REAI.

Resilience as a Protective Factor in Basic Military Training, a Longitudinal Study of the Swiss Armed Forces.

For recruits, basic military training (BMT) can be experienced as a stressful episode in which relevant protective factors such as resilience might be essential for successful completion of the training. The present study examined whether resilience would act as a protective factor during BMT in the Swiss Armed Forces. To this end, we conducted a cross-sectional and longitudinal study of resilience and psychological burden. At the beginning of the BMT and at week 11, 525 male recruits (mean age: 20.3 years) completed a series of questionnaires covering demographic information and assessing resilience, perceived stress and mental distress. In parallel, their superiors rated recruits' military performance in week 13. Dropout rates were also registered. Cross-sectionally and longitudinally, higher resilience scores predicted lower scores for perceived stress, mental distress, and better military performance. Higher self-rated resilience was moderately associated with military performance, as rated by recruits' superiors. Resilience scores, perceived stress and mental distress did not differ between those recruits continuing their BMT and dropouts. In support of our assumptions, resilience acted as a protective factor during Swiss Armed Forces BMT.