OBJECTIVE:Literature on pediatric acute limb ischemia (PALI) is scarce with controversial management regarding diagnostics and treatment. The aim of this review was to evaluate the management of PALI. METHODS:A systematic literature search (PubMed, Embase, Cochrane Library) following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was performed (Prospero registration number CRD420251035570). All English full-text studies published in the past 30 years reporting on acute limb ischemia in children were included. Cases series and cohorts with fewer than 10 patients were excluded from the pooled analysis. Primary outcomes were treatment modalities and diagnostics used. Secondary outcomes were recorded mortality directly linked to PALI and the etiology of PALI, as well as long-term morbidity and amputation rates. RESULTS:In all, 17 studies (2484 children; 66.3% male; mean age, 2.14 years) were included in the quantitative synthesis. In 89.9%, PALI was caused by arterial cannulation. The most commonly affected location was the common femoral artery (49.8%). Ultrasound was the most commonly used diagnostic means. Conservative treatment of PALI was first-line treatment in 87% and was considered successful without the need for surgical intervention (65% of reports; 11/17). Surgery was reserved for failed conservative treatment with an amputation rate of 2.4%. Mortality directly related to PALI was low (0.01%). CONCLUSIONS:Acute ischemia in pediatric patients most often occurred iatrogenically. Conservative treatment proved to be successful and should be considered as the treatment of choice.

Die periphere arterielle Verschlusskrankheit (PAVK) zählt mit weltweit rund 237 Mio. Betroffenen zu den häufigsten Gefäßerkrankungen und weist eine steigende Prävalenz auf, insbesondere durch die Zunahme von Risikofaktoren wie Diabetes mellitus, Hypertonie, Hypercholesterinämie und Nikotinkonsum. Sie ist nicht nur eine eigenständige Erkrankung, sondern auch ein Indikator für systemische kardiovaskuläre Morbidität und Mortalität, wobei Todesursachen meist kardial oder zerebrovaskulär bedingt sind. Eine exzellente Versorgung erfordert eine individualisierte, initiale Planung unter Einbeziehung konservativer, endovaskulärer und offen-chirurgischer Verfahren. Im Stadium der Claudicatio intermittens steht zunächst die konservative Therapie im Vordergrund, insbesondere strukturiertes Gehtraining und konsequentes Best-Medical-Treatment. Eine Revaskularisation sollte erst nach Ausschöpfung dieser Maßnahmen und unter Berücksichtigung der Langzeitstabilität erfolgen. Der Nachsorge kommt eine zentrale Bedeutung zu, wobei neben klinischen Parametern auch patientenberichtete Outcomes berücksichtigt werden sollten. Bei der chronisch-kritischen Extremitätenischämie (CLTI) ist eine rasche, individualisierte und interdisziplinär abgestimmte Therapie erforderlich. Die Wahl zwischen offenen und endovaskulären Verfahren sollte patientenspezifisch erfolgen, idealerweise im Rahmen strukturierter Gefäßboards. Moderne Verfahren wie Mikroperfusionsmessungen können die Therapieplanung und Verlaufskontrolle unterstützen. Für No-Option-Patienten stehen innovative Ansätze zur Verfügung, um Amputationen möglichst zu vermeiden. Die Behandlungsqualität wird wesentlich durch Erfahrung und Fallzahlen beeinflusst, wobei Hochvolumen-Zentren bessere Ergebnisse zeigen. Einheitliche Qualitätsindikatoren fehlen bislang. Insgesamt basiert Exzellenz in der PAVK-Therapie auf individualisierter Planung, interdisziplinärer Entscheidungsfindung, strukturierter Nachsorge und kontinuierlicher Qualitätssicherung.

BACKGROUND:Peripheral arterial disease (PAD) affects more than 200 million people worldwide, with symptoms ranging from none to severe. Despite these different diagnostic options, patients with unclear leg pain remain challenging to diagnose. The primary objective of this study was to evaluate whether multispectral optoacoustic tomography (MSOT) can discriminate between healthy volunteers (HV) and patients with intermittent claudication (IC) by assessing hemoglobin-related biomarkers in calf muscle tissue. METHOD:In this monocentric, cross-sectional, observational diagnostic trial (NCT05373927) n = 102 patients were included in two independent derivation (DC, n = 51) and validation cohorts (VC, n = 51). MSOT was performed before and after standardized heel raise provocation and was compared to standardized PAD diagnostics including pulse palpation, ankle brachial index (ABI), duplex sonography, 6-minute walk test (6MWT), assessment of health-related quality of life (VASCUQOL-6), and angiography (aggregated TransAtlantic Inter-Society Consensus classification, aTASC). RESULTS:Here we show that MSOT is capable of differentiating IC and HV with an area under the receiver operator characteristics curve (AUROC) in DC by 0.99 (sensitivity: 100%, specificity: 95.8%) and in the VC by 0.95 (sensitivity: 96.2%, specificity: 96.0%). MSOT-derived oxygenation positively correlates with the ABI post-exercise (R = 0.83, P = 2.31 × 10-26), the absolute walking distance in the 6MWT (R = 0.77, P = 3.40 × 10-21), the VASCUQOL-6 (R = 0.79, P = 4.82 × 10-23) and negatively with aTASC classification (R = -0.80, P = 2.92 × 10-24). CONCLUSIONS:Post-exercise MSOT-derived saturation in the calf muscle is validated as a non-invasive imaging biomarker to distinguish HV and IC patients yielding high sensitivity and specificity.

Introduction: Although major amputations can often be avoided due to evolving methods of endovascular and surgical revascularizations techniques, in patients with chronic limb-threatening ischemia, it is still necessary in some cases. Aim of this study was the detection of wound healing disorders through intraoperative microcirculation measurements in major limb amputations. Materials and methods: In this single-center clinical study, patients with an indication for major amputation were enrolled prospectively. Cause of amputation, patients’ comorbidities including cardiovascular risk profile were assessed. Macrocirculation, as well as microcirculation were assessed. Microcirculation measurements were performed by fluorescence angiography with the administration of indocyanine green. A preoperative measurement was obtained at the amputation level, followed by three additional measurements of the amputation stump postoperatively. Wound healing was monitored and correlated with the microcirculatory findings, based on the perfusion parameters ingress and ingress rate, calculated in the indocyanine green fluorescence video sequences of the amputation stumps. Results: Forty-five patients were enrolled, including 19 (42%) below-the-knee amputations and 26 (58%) above-the-knee amputations. When considering the need for revision, a change in the microperfusion parameters was observed postoperatively. The mean value for ingress was significantly lower directly postoperatively in stumps requiring revisions (5 ± 0 A.U. versus 40.5 ± 42.5 A.U., p < 0.001). The mean value of ingress rate behaved similarly (0.15 ± 0.07 A.U./s versus 2.8 ± 5.0 A.U./s, p = 0.005). The evaluation of indocyanine green measurements when wound healing disorders occurred also showed nonsignificant differences in the mean values. Conclusion: Fluorescence angiography after major lower limb amputations appears to be an option of depicting microperfusion. Especially, the early postoperative detection of reduced perfusion can indicate a subsequent need for revision. Therefore, this method could possibly serve as a tool for intraoperative quality control after major limb amputation.

The heterogeneous clinical manifestations of peripheral arterial occlusive disease (PAOD) necessitate a systematic stepwise diagnostic procedure as well as a stage-related and realistic target-oriented treatment. Although preventive medical aspects in all stages of the disease are currently considered the foundations of complementary treatment before, during and after every invasive revascularization, open surgical, interventional and hybrid procedures can be carried out to improve symptoms and to save the limbs. The choice of appropriate approaches and their combination is oriented to patient-specific factors and also the local expertise and infrastructure. All technical decisions should consider the alternative complementary treatment approaches in a balanced way. In addition to the PAOD-associated case volume of the hospital and the patient-specific risk factors, the adherence to guideline-compliant recommendations in particular is an important predictor of the long-term treatment results.

In der aortoiliakalen Strombahn wird eine Zunahme der endovaskulären Therapie beobachtet. Im Falle ausgedehnter Läsionen („transatlantic inter-society consensus“ TASC II C und D) stellt jedoch die offene Chirurgie weiter eine essenzielle Säule der Therapie dar. Vor offener Chirurgie ist die CT-Angiographie der Aorta zur Beurteilung der Kalklast und des Klemmsegments sinnvoll. Bei nicht signifikant unterschiedlicher Krankenhausmortalität (1,4 vs. 2,9

BACKGROUND:Carotid endarterectomy (CEA) is a well-established standard therapy for patients with symptomatic or asymptomatic high-grade carotid stenosis. The aim of carotid endarterectomy is to decrease the risk of stroke and avoid relevant functional loss. However, carotid endarterectomy is known to be associated with hemodynamic dysregulation. In this study we compared eversion CEA (E-CEA) and conventional CEA (C-CEA) regarding postoperative blood pressure values as well as preoperative and postoperative baroreceptor sensitivity in the first 7 days after surgery. The aim was to find possible factors influencing changes in baroreceptor sensitivity. METHODS:Patients (111 patients were enrolled, of which 50 patients received C-CEA and 61 patients E-CEA) were prospectively enrolled in this study. For the measurement of baroreceptor sensitivity, a noninvasive Finometer measuring device from Finapres Medical System B.V. (Amsterdam, The Netherlands) was used. Measurements were performed 1 day before surgery (PRE), directly after surgery (F1), on day 1 (F2), day 2 (F3), and on day 7 (F4) postoperatively. RESULTS:Postoperative blood pressure values were significantly higher in the E-CEA group on the day of surgery (F1) (P < 0.001) and on day 1 (F2) (P < 0.001). From day 2 (F3, F4) postoperatively, no significant difference was found between the 2 groups. The invasive blood pressure measurement in the postoperative recovery room showed significantly higher systolic blood pressure values in the E-CEA group (P = 0.001). The need of acute antihypertensive therapy was significantly higher in the recovery room in the E-CEA group (P = 0.020). With regard to changes in baroreceptor sensitivity, significantly lower baroreceptor sensitivity (BRS) values were recorded in the E-CEA group at 1 day (F2) postoperatively (P = 0.005). The regression analysis showed that the applied surgical technique and the patient's age were significant factors influencing changes in baroreceptor sensitivity. CONCLUSIONS:In this study we could confirm higher blood pressure levels after E-CEA in the first 2 days after surgery. Additionally, we identified 22 factors possibly influencing baroreceptor sensitivity: surgical technique and age. Based on the data obtained in this study, hemodynamic dysregulation after CEA (E-CEA, C-CEA) is temporary and short-term. Already after the second postoperative day, there was no significant difference between the E-CEA and E-CEA groups, this effect remained stable after 7 days.

Background: Arterio-venous fistulas (AVF) are used as first-line access for hemodialysis (HD) in the pediatric population. The aim of this investigation was to describe a single-center experience in the creation of AVF, together with its patency in children. Methods: This single-center retrospective study included all patients aged ≤18 years with AVFs created between 1993 and 2023. The collected data included patients’ demographics, hemodialysis history, intraoperative data, and required reinterventions in order to determine the impact of these variables on primary, primary-assisted, and secondary patency. Results: Fifty-seven patients were analyzed with a median age of 15 years (range, 7–18 years). Fifty-four forearm and four upper arm fistulas were performed. The median follow-up was 6.9 years (range, 0–23 years). The primary failure rate was 10.5%. The primary patency rate was 67.6%, 53.6%, 51.4%, and 38.1% after 1, 3, 5, and 10 years; primary-assisted patency was 72.9%, 62.8%, 60.6%, and 41.5%; and secondary patency was 87.3%, 81.3%, 76.8%, and 66.6% after 1, 3, 5, and 10 years in the studied population. Conclusions: AVFs showed an acceptable rate of primary failure and excellent long-term patency. In this context, AVFs are an appropriate option for HD access, especially in pediatric patients.

Soft-tissue sarcomas (STS) are rare, but potentially life-threatening malignancies. STS can occur anywhere in the human body with the limbs being the most common site. Referral to a specialized sarcoma center is crucial to guarantee prompt and appropriate treatment. STS treatment strategies should be discussed in an interdisciplinary tumor board to involve expertise from all available resources, including an experienced reconstructive surgeon for an optimal outcome. In many cases, extensive resection is needed to achieve R0 resection, resulting in large defects after surgery. Hence, an evaluation of whether plastic reconstruction might be required is mandatory to avoid complications due to insufficient primary wound closure. In this retrospective observational study, we present data of patients with extremity STS treated at the Sarcoma Center, University Hospital Erlangen, in 2021. We found that complications were more frequent in patients who received secondary flap reconstruction after insufficient primary wound closure compared to patients who received primary flap reconstruction. Additionally, we propose an algorithm for an interdisciplinary surgical therapy of soft-tissue sarcomas regarding resection and reconstruction and present two problematic cases to emphasize the complexity of surgical sarcoma therapy.

Background: Aim of this study was to assess the influence of intermitted negative pressure (INP) therapy on the foot microcirculation in patients with no-option CLTI. Patients and methods: CLTI patients defined as no option for revascularization on the basis of an interdisciplinary vascular board decision (interventional radiology, vascular surgery) were included in this study. INP therapy was performed at home. Therapy regime was: 1 hour twice daily. Follow-up was after 6 weeks and 3 months. Microcirculation measurement was performed by laser Doppler flowmetry and white light spectrometry (oxygen to see, O2CTM). Following parameters were evaluated: oxygen saturation (sO2 in%), relative hemoglobin (rHb) and flow (in arbitrary units A.U.). Additionally the clinical outcome of the patients was assessed. Results: From September 2020 to June 2022, 228 patients were screened. In total 19 patients (13 men, 6 women, mean age was 73.95 years) were included. 6 weeks after INP therapy the microcirculation showed a significant improvement for the parameter sO2 (%) (p=0.004). After 3 months a non-significant decrease compared to 6 weeks follow-up was seen for the parameter sO2; however, the perfusion was still improved compared to baseline measurement. With regard to the microperfusion values flow (AU) and hemoglobin (AU), the changes were not significant. Clinically, the patients reported a significant reduction of rest pain after therapy (p=0.005). Conclusions: INP therapy in no-option CLTI patients showed a significant improvement of the skin perfusion after 6 weeks. Therefore, INP therapy might have therapeutic potential in these critical ill patients.

Peripheral arterial disease (PAD) leads to chronic vascular occlusion and results in end organ damage in critically perfused limbs. There are currently no clinical methods available to determine the muscular damage induced by chronic mal-perfusion. This monocentric prospective cross-sectional study investigated n = 193 adults, healthy to severe PAD, in order to quantify the degree of calf muscle degeneration caused by PAD using a non-invasive hybrid ultrasound and single wavelength optoacoustic imaging (US/SWL-OAI) approach. While US provides morphologic information, SWL-OAI visualizes the absorption of pulsed laser light and the resulting sound waves from molecules undergoing thermoelastic expansion. US/SWL-OAI was compared to multispectral data, clinical disease severity, angiographic findings, phantom experiments, and histological examinations from calf muscle biopsies. We were able to show that synergistic use of US/SWL-OAI is most likely to map clinical degeneration of the muscle and progressive PAD.

Treatment of complex ischemic lower leg defects with exposure of deep anatomic structures represents a considerable challenge to involved specialties. In selected patients, limb salvage can be achieved as an alternative to major amputation by means of a combined approach including arterial reconstruction and subsequent free flap transfer. Arterial reconstruction can be performed either by endovascular or open surgical treatment (bypass reconstruction or implantation of an arteriovenous loop) preliminary to defect reconstruction using microsurgical free flap transplantation. Whereas the aim of the arterial reconstruction comprises the establishment of sufficient perfusion and creation of adequate target vessels for the free flap transfer, the selection of the appropriate flap entity depends on the extent of the wound as wells as on the presence of osteomyelitis. Arterial reconstruction and defect reconstruction can be performed as one-stage or two-stage procedure and has become an established and feasible treatment approach in centers. Evaluation of microperfusion by means of indocyanine green can further increase safety and feasibility of this method. Against this background, combined arterial reconstruction and subsequent free flap transfer provides excellent results in terms of amputation free survival and postoperative mobility. Essential is however an individualized decision making in consideration of patient selection and possible contraindications. This approach may be evaluated in mobile patients with complex wounds prior to major amputation.

Background Multispectral optoacoustic tomography (MSOT), a molecular sensitive ultrasound, offers a non-invasive diagnostic approach to image the deep-tissue biomarkers. Objectives The authors aimed to investigate the diagnostic accuracy of MSOT to distinguish between healthy volunteers (HV) and patients with intermittent claudication (IC) by assessing hemoglobin-related biomarkers in calf muscle tissue. Methods In this monocentric, cross-sectional diagnostic trial using derivation (DC) and validation cohorts (VC) yll subjects underwent standardized PAD diagnostics. This included pulse palpation, ankle brachial index (ABI), duplex sonography, 6-minute walk test (6MWT), and assessment of health-related quality of life (VASCUQOL-6). The vascular occlusion profile in IC patients was confirmed by angiography (aggregated TransAtlantic Inter-Society Consensus classification, aTASC). MSOT imaging of calf muscle was performed before and after standardized heel raise provocation. Participants Of 123 screened individuals, 102 completed the study. MSOT-derived oxygenation (msO 2 ) after the exercise differentiated IC and HV with an area under curve the receiver operator characteristics curve (AUROC) in DC by 0.99 (95%CI 0.97;1.00, p<0.001, sensitivity: 100%, specificity: 95.8%) and in the VC by 0.95 (95%CI 0.95;1.00, p<0.001, sensitivity: 96.2%, specificity: 96.0%). mSO 2 positively correlated with the ABI post-exercise (R=0.83, 95%CI 0.75;0.88, P<0.001), the absolute walking distance in the 6MWT (R=0.77, 95%CI 0.68;0.84, P<0.001), the VASCUQOL-6 (R=0.79, 95%CI 0.70;0.85, P<0.001) and negatively with aTASC classification (R=-0.80, 95%CI -0.86;-0.72, P<0.001). Conclusions Post-exercise MSOT-derived saturation in the calf muscle was validated as a new and promising diagnostic biomarker to distinguish between HV and IC patients yielding high sensitivity and specificity. ( NCT05373927 )

Background: This retrospective case series study aims to demonstrate a salvage technique for the treatment of carotid blow-out syndrome (CBS) in irradiated head and neck cancer patients with a vessel-depleted neck. Methods: Between October 2017 and October 2021, two patients (N = 2) with CBS were treated at our institution in a multidisciplinary approach together with the Department of Vascular Surgery. Patients were characterized based on diagnoses, treatment procedures, and the subsequent postoperative course. Results: Surgical emergency intervention was performed in both cases. The transition zone from the common carotid artery (CCA) to the internal carotid artery (ICA) was resected and reconstructed with a xenogic (case 1) or autogenic (case 2) interposition (end-to-end anastomosis). To allow reconstruction of the vascular defect, an additional autologous vein graft was anastomosed to the interposition graft in an end-to-side technique, allowing arterial anastomosis for a free microvascular flap without re-clamping of the ICA. Because of the intraoperative ICA reconstruction, none of the patients suffered a neurological deficit. Conclusions: The techniques presented in the form of two case reports allow for acute bleeding control, cerebral perfusion, and the creation of a vascular anastomosis option in the vessel-depleted neck.

Background: Arteriovenous (AV) loops help to overcome absent or poor-quality recipient vessels in highly complex microvascular free flap reconstruction cases. There are no studies on blood flow and perfusion patterns. The purpose of this study was to evaluate and compare intraoperative hemodynamic characteristics of AV loops followed by free tissue transfer for thoracic wall and lower extremity reconstruction. Methods: this prospective clinical study combined Transit-Time Flowmetry and microvascular Indocyanine Green Angiography for the assessment of blood flow volume, arterial vascular resistance and intrinsic transit time at the time of AV loop construction and on the day of free flap transfer. Results: A total of 11 patients underwent AV loop creation, of whom five required chest wall reconstruction and six required reconstruction of the lower extremities. In seven of these cases, the latissimus dorsi flap and in four cases the vertical rectus abdominis myocutaneous (VRAM) flap was used as a free flap. At the time of loop construction, the blood flow volume of AV loops was 466 ± 180 mL/min, which increased to 698 ± 464 mL/min on the day of free tissue transfer (p > 0.1). After free flap anastomosis, the blood flow volume significantly decreased to 18.5 ± 8.3 mL/min (p < 0.001). There was no significant difference in blood flow volume or arterial vascular resistance between latissimus dorsi and VRAM flaps, nor between thoracic wall and lower extremity reconstruction. However, a significant correlation between the flap weight and the blood flow volume, as well as to the arterial vascular resistance, was found (p < 0.05). Conclusion: This is the first study to perform intraoperative blood flow and hemodynamic measurements of AV loops followed by free tissue transfer. Our results show hemodynamic differences and contribute to deeper understanding of the properties of AV loops for free flap reconstruction.

Zusammenfassung Komplexe, ischämische Wunden im Bereich der unteren Extremität mit freiliegenden tiefen Strukturen stellen große Herausforderungen an die behandelnden Fachdisziplinen dar. Als Alternative zur Majoramputation ergibt sich für ausgewählte Patienten die Möglichkeit eines kombinierten Verfahrens mittels arterieller Rekonstruktion und nachfolgender mikrochirurgischer Defektdeckung durch eine freie Lappentransplantation. Als arterielle Rekonstruktionsverfahren stehen endovaskuläre oder offen chirurgische Verfahren wie Bypassrekonstruktion oder Implantation eines arteriovenösen Loops als Vorbereitung für die Defektdeckung zur Verfügung. Ziel der arteriellen Rekonstruktion ist die Schaffung einer ausreichenden Perfusion zur Defektdeckung an der Extremität sowie die Schaffung von Anschlussgefäßen für die Lappentransplantation. Die Auswahl des Lappens richtet sich u. a. nach der Größe und Ausdehnung des Defektes sowie nach dem Vorhandensein einer Osteomyelitis. Dies kann ein- oder zweizeitig erfolgen. In Zentren ist dieses kombinierte Vorgehen als sichere Methode etabliert. Die Mikroperfusionsanalyse des Gewebes mittels Indocyaningrün erhöht nochmals die Sicherheit des Verfahrens und kann Perfusionsdefizite aufzeigen. Das kombinierte Verfahren mittels arterieller Rekonstruktion und freiem Gewebetransfer liefert gute Langzeitergebnisse im Hinblick auf amputationsfreies Überleben und postoperative Mobilität. Wichtig für die Indikationsstellung ist eine korrekte Patientenselektion unter Berücksichtigung der Kontraindikationen. Dieses Verfahren sollte für alle mobilen Patienten mit komplexen Weichteildefekten vor einer Majoramputation evaluiert werden.

Ureteral stenosis and urinary leakage are relevant problems after kidney transplantation. A standardized definition of ureterovesical anastomosis complications after kidney transplantation has not yet been established. This study was designed to demonstrate the predictive power of quantitative indocyanine green (ICG) fluorescence angiography. This bicentric historic cohort study, conducted between November 2015 and December 2019, included 196 kidney transplantations. The associations between quantitative perfusion parameters of near-infrared fluorescence angiography with ICG and the occurrence of different grades of ureterovesical anastomosis complications in the context of donor, recipient, periprocedural, and postoperative characteristics were evaluated. Post-transplant ureterovesical anastomosis complications occurred in 18%. Complications were defined and graded into three categories. They were associated with the time on dialysis (p = 0.0025), the type of donation (p = 0.0404), and the number of postoperative dialysis sessions (p = 0.0173). Median ICG ingress at the proximal ureteral third was 14.00 (5.00–33.00) AU in patients with and 23.50 (4.00–117.00) AU in patients without complications (p = 0.0001, cutoff: 16 AU, sensitivity 70%, specificity 70%, AUC = 0.725, p = 0.0011). The proposed definition and grading of post-transplant ureterovesical anastomosis complications is intended to enable valid comparisons between studies. ICG Fluorescence angiography allows intraoperative quantitative assessment of ureteral microperfusion during kidney transplantation and is able to predict the incidence of ureterovesical anastomosis complications. Registration number: NCT-02775838.