Lower Limb Revascularization Procedures Research Articles

Endovascular revascularization of critical limb ischemia: the role of ultrasound-guided popliteal sciatic nerve block for the procedural pain management.

To evaluate the impact of the ultrasound-guided popliteal sciatic nerve block (PSNB) for pain management during endovascular treatment of chronic limb-threatening ischemia (CLTI). From November 2020 to January 2022, 111 CLTI patients that underwent endovascular procedures were prospectively enrolled in this prospective single-arm interventional study. Ultrasound-guided PSNB was used for procedural pain control. Pain intensity was evaluated throughout the procedure (baseline, 10min after the block, pain peak, and at the end of the procedure) with the visual analog scale (VAS). Forty-six patients underwent above-the-knee revascularization (ATK), 20/111 below-the-knee (BTK) revascularization, 20/111 to both ATK and BTK revascularization. In 25 cases, no endovascular option was feasible at diagnostic angiography. The PSNB was effective in 96% of patients, with no need for further pain management with a statistically significant reduction (p < 0.0001) in the mean value of the VAS from 7.86 ± 1.81 (pre-procedural) to 2.04 ± 2.20 after 10min from the block and up to 0.74 ± 1.43 at the end of the procedure (mean time 43min). Only 1 complication related to the popliteal sciatic nerve block was registered (a temporary foot drop, completely resolved within 48h). The time necessary to perform the block ranged between 4 and 10min. Ultrasound-guided PSNB is a feasible and effective method to manage patients with rest pain and increase comfort and compliance during endovascular procedures. An ultrasound-guided popliteal sciatic nerve block is a safe, feasible, and effective technique to manage pain during endovascular treatment of chronic limb-threatening ischemia, especially in frail patients with multiple comorbidities who are poor candidates for deep sedoanalgesia or general anesthesia. Endovascular treatment of CTLI may require long revascularization sessions in patients with high levels of pain at rest, which could be exacerbated during the revascularization procedure. The PSNB is routinely used for anesthesia and analgesia during foot and ankle surgery, but the experience with lower limb revascularization procedures is very limited and not included in any international guideline. Ultrasound-guided PSNB is a feasible and effective regional anesthesia technique to relieve procedural and resting pain. Because of its safety and availability, every interventional radiologist should know how to perform this type of loco-regional anesthesia.

Foot Dorsal and Plantar Flexion to Enhance Crossing of Tortuous Highly-Calcific Ankle Vessels During Lower Limb Revascularization Procedures: A Technical Note.

To describe a crossing technique of stenotic/occluded and tortuous highly calcific ankle vessels during complex percutaneous limb salvage intervention in diabetic patients with ischaemic foot ulcers (Rutherford 5 and 6). We propose a simple technique to achieve "straightening" of the tortuous vessel and allow safe devices passage into the foot arteries, Patients were asked to hold their foot in plantar or dorsal flexion, accordingly to the treated artery. If unable to do so, an equipe member executed the manoeuvre on their behalf. The technique was applied in 148 cases, with a success rate of 81% (120/148). No complications related to the manoeuvre were observed. Crossing of tortuous distal crural vessels can be challenging in diabetic patients; in our experience, this technique can be auseful tool to obtain a successful recanalization in complex procedures with high risk of failure.

Impact of the COVID-19 Epidemic on hospitalization for diabetic foot ulcers during lockdown: A French nationwide population-based study.

The aim of this study was to examine the impact of the COVID-19 epidemic on the hospitalization rates for diabetic foot ulcer (DFU), osteomyelitis and lower limb revascularization procedure in people with DFU. This nationwide retrospective cohort study included hospital data on all people hospitalized in France for diabetes in weeks 2-43 in 2020, including the COVID-19 lockdown period, compared to same period in 2019. The number of hospitalizations for DFU decreased significantly in weeks 12-19 (during the lockdown) (p<10-4 ). Hospitalization for foot osteomyelitis also decreased significantly in weeks 12-19 (p<10-4 ). The trend was the same for lower limb amputations and revascularizations associated with DFU or amputation. The marked drop in hospitalization rates for DFU, osteomyelitis and lower limb revascularization procedures in people with DFU observed in France during the lockdown period suggests that COVID-19 was a barrier to DFU care, and may illustrate the combined deleterious effects of hospital overload and changes in health-related behaviour.

Experimental Model to Assess the Efficacy and Safety of Vessel Sealing Devices in By-pass Surgery

Introduction - Energy sealing devices achieve hemostasis of blood vessels through sequential coagulation and tissue transection. The most frequently used ones are: Electrothermal Bipolar Tissue Sealing System (EB) and Harmonic Scalpel (HS). Both methods are based on denaturation and fusion of proteins of the vessel wall (mainly collagen and elastin) by controlled delivery of energy: electrothermal by radiofrequency and impedance feed-back (EB) or high frequency ultrasound vibration (HS). Although its use has been widely spread in multiple surgical fields, most vascular surgeons are not confident enough about its safety for sealing collaterals of autologous grafts during by-pass surgery. The aim of this study was to compare the efficacy and safety of EB and HS with conventional vessel ligation of saphenous vein (SV) collaterals in an experimental model. Methods - Twenty-five fragments of SV were extracted from cadaver donor (n=6) or from residual fragments during amputation or lower limb revascularization procedures (n=19). To simulate physiological conditions, a pulsatile flow circuit was performed with a roller pump, and intravascular pressure was recorded by a pressure gauge and a pressure monitor. In each fragment, two venous collateral seals were made, one by conventional ligation with 3/0 silk (control) and the other one with EB (N= 13) or HS (N= 12), after sequentially consecutive assignment. Each venous fragment was then incorporated into the pulsatile flow circuit, and the pressure was progressively increased until 300 mmHg (supraphysiological) was reached, or until sealing breakage occurred. Collateral vein diameter, burst pressures, and leakage points were recorded. A histological study with hematoxylin-eosin and Masson's trichrome stain was also performed for each energy-sealing device. A descriptive analysis and analytical statistical tests (U-Mann Whitney, Chi-square) were performed. Results - The mean diameter of the venous collaterals was 2.42±0.7mm and 2.38±0.6 mm, p = NS, for EB and HS, respectively. The mean burst pressure was slightly higher for EB than for HS (788.9±455.0 mmHg vs 602.5±363.1 mmHg, p = 0.268). In only one case (HS) the outbreak occurred in the sealing zone at pressures below 300 mmHg. In all cases for EB, the rupture occurred at supraphysiological pressures.The leakage point for HS occurred in sealed collateral in all cases (12/12). For EB, the leakage point occurred in its sealing zone in 8 of 13 fragments, and in the conventional ligation (control), in the remaining 5 fragments (p=0.016). The histological study showed no differences in the tissues coagulated by both devices. Conclusion - Vessel sealing devices are as effective and safe for the hemostasis of saphenous vein collaterals as conventional ligation. These devices may be useful given their fast sealing time and easy handling during surgical venous graft preparation for lower limb revascularization. In our study, the EB showed greater strength in the sealing of saphenous vein collaterals compared to HS, however the outbreak occurred at supraphysiological pressures, so this fact may not have clinical relevance. References-Toishi M, Yoshida K, Agatsuma H et al. Usefulness of vessel-sealing devices for <7mm diameter vessels: a randomized controlled trial for human thoracoscopic lobectomy in primary lung cancer. Interactive CardioVascular and Thoracic Surgery, 2014 (19): 448-55.-Rajbabu K, Baber NJ, Chol W et al. To knot or not to knot? Sutureless haemostasis compared to the surgeons's knot. Ann R Coll Surg Engl, 2007; 89: 359-62.-Lamberton GR, Hsi R, Jin D et al. Prospective comparision of four laparoscopic vessel ligation devices. Journal of endourology, 2008; 22: 1-6.-Lacin T, Batirel HF, Ozer K et al. Safety of a thermal vessel sealer on main pulmonary vessels. European Journal of Cardio-thoracic Surgery, 2007; 31: 482-85.

A MultiCenter Pilot Randomized Controlled Trial of Remote Ischemic Preconditioning in Major Vascular Surgery.

A pilot randomized controlled trial that evaluated the effect of remote ischemic preconditioning (RIPC) on clinical outcomes following major vascular surgery was performed. Eligible patients were those scheduled to undergo open abdominal aortic aneurysm repair, endovascular aortic aneurysm repair, carotid endarterectomy, and lower limb revascularization procedures. Patients were randomized to RIPC or to control groups. The primary outcome was a composite clinical end point comprising any of cardiovascular death, myocardial infarction, new-onset arrhythmia, cardiac arrest, congestive cardiac failure, cerebrovascular accident, renal failure requiring renal replacement therapy, mesenteric ischemia, and urgent cardiac revascularization. Secondary outcomes were components of the primary outcome and myocardial injury as assessed by serum troponin values. The primary outcome occurred in 19 (19.2%) of 99 controls and 14 (14.1%) of 99 RIPC group patients (P = .446). There were no significant differences in secondary outcomes. Our trial generated data that will guide future trials. Further trials are urgently needed.

La mujer y la enfermedad vascular: características específicas

Men have a higher prevalence in most vascular diseases and women are under-represented in the mayority of the trials. Therefore, a vast mayority of clinical decisions based on these, might not be suitable for women.A review of current recommendations and the literature is presented to help to identify gender differences for patients with abdominal aortic aneurysms, carotid artery disease, and peripheral arterial disease. Most of them emphasize that women are older than men and cardiovascular risk factors are under-treated in comparison to men.The evidence suggests that women are at higher risk of aneurysm rupture when compared with men and that, when rupture occurs, it does so at smaller diameters with higher morbidity and mortality, whether by open or endovascular repair.For carotid disease, it has been suggested that carotid plaques in women tend to be more stable, which may result in surgery not being as effective as in males, and should be more restrictive when operating asymptomatic or symptomatic women with moderate stenosis (50-69%).Finally, regarding lower limb revascularization procedures, there is not enough evidence to show differences between sexes in patency, limb salvage rate, perioperative mortality, or long-term survival.

Post-implant evaluation of the anastomotic mechanical and geometrical coupling between human native arteries and arterial cryografts implanted in lower-limb: Mechanical, histological and ultraestructural studies of implanted cryografts

Background There is an urgent need of vascular substitutes (VS) to be used in lower limb revascularization procedures when autologous veins are not available and synthetic prosthesis are contraindicated. Since the mechanical differences with respect to native vessels are determinants of the VS failure, the substitutes should have mechanical properties similar to those of the recipient vessels. The use of cryopreserved arteries (cryografts) could overcome limitations of available VS. These work aims were to characterize (a) native vessels/implanted cryografts mechanical and geometrical coupling, (b) cryografts capability to ensure mismatch levels lesser than those expected for expanded polytetrafluoroethylene (ePTFE), (c) cryografts functional properties considering their histological and ultra-structural characteristics. Methods Instantaneous pressure (mechano-transducers) and diameter (B-mode echography) were obtained in implanted femoro-popliteal, ileo-femoro-popliteal and axilo-humeral cryografts ( n = 8), in femoral arteries from recipients ( n = 8), recipient-like ( n = 15) and multiorgan donors-like ( n = 15) subjects, and in ePTFE segments ( n = 10). Calculus: (a) Mechanical parameters: elastic modulus, arterial compliance, distensibility and characteristic impedance; (b) Arterial remodeling: diameter, wall thickness, cross-sectional area and wall-to-lumen ratio; (c) Native vessels/VS coupling. Histological and structural analysis were done in explanted femoro-popliteal and axilo-humeral cryografts ( n = 7). Results Post-implant the cryografts remodeled. Their stiffness increased and the conduit function diminished. Remodeling resulted in an improvement in native vessels/cryograft coupling, which was always better than native vessels/ePTFE coupling. Conclusions Post-implant cryograft remodeling improved native vessels/cryografts coupling. Cryografts would have mechanical and geometrical advantages over ePTFE. Anastomotic cryograft remodeling differed from that expected only due to haemodynamic factors. The structural properties of the remodeled cryografts contribute to explain their functional characteristics.

Lower-limb revascularization and major amputation rates in England

The aim was to establish national data for lower-limb revascularization and major amputation procedures performed in England. Data for lower-limb revascularization procedures and major amputations were collected from the Hospital Episode Statistics (finished consultant episodes) which is published yearly by the Department of Health. Transluminal procedures were analysed from 1998 onwards. Age adjustment was performed according to figures for the resident population of England in the interval studied. In all age groups, revascularization rates initially increased to a peak in the mid-1990 s. This was followed by a steady decline in procedures to the present day. However, amputations gradually increased in the 45-64-years age group and showed only a slight decline in the 65-74-years age group. Among patients aged over 75 years there was a marked decline from the mid-1990 s to present-day. Data for diabetics showed similar trends. The national rate of amputation initially rose despite an increasing number of vascular interventions. It is significant, however, that among patients aged over 75 years this has been followed by a decrease in both revascularization procedures and amputation rates to present levels, the lowest for 14 years.