Interventions for thrombosed haemodialysis arteriovenous fistulas and grafts.

BACKGROUND: Patients who present with problems with definitive dialysis access (arteriovenous fistula (AVF) or arteriovenous graft (AVG)) become catheter dependent (temporary access), a condition that often carries a higher risk of infections, central venous occlusions and recurrent hospitalisations. For AVG, primary patency rates are reported to be 30% to 90% in patients undergoing thrombectomy or thrombolysis. According to the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative (NKF-KDOQI) guidelines, surgery is preferred when the cause of the thrombosis is a stenosis at the site of the anastomosis in thrombosed AVF. The European Best Practice Guidelines (EBPG) reported that thrombosed AVF may be preferably treated with endovascular techniques, but when the cause of thrombosis is in the anastomosis, surgery provides better results with re-anastomosis. Therefore, there is a need to carry out a systematic review to determine the effectiveness and safety of the intervention for thrombosed fistulae. OBJECTIVES: This review aims to establish the efficacy and safety of interventions for failed AVF and AVG in patients receiving haemodialysis (HD). SEARCH METHODS: We searched the Cochrane Kidney and Transplant Register of Studies up to 28 January 2024 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, EMBASE, conference proceedings, the International Clinical Trials Registry Portal (ICTRP) Search Portal and ClinicalTrials.gov. SELECTION CRITERIA: The review included randomised controlled trials (RCTs) and quasi-RCTs in people undergoing HD treatment using AVF or AVG presenting with clinical or haemodynamic evidence of thrombosis. Patients had to have used an AVF or AVG at least once. DATA COLLECTION AND ANALYSIS: Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS: Our search strategy identified 14 eligible studies (1176 randomised participants) for inclusion in this review. We included three types of interventions for the treatment of thrombosed AVF and AVG: (1) types of thrombectomy, (2) types of thrombolysis and (3) surgical procedures. Most of the included studies had a high risk of bias due to a poor study design, a low number of patients and industry involvement. Overall, there was insufficient evidence to suggest that a specific intervention was better than another for the outcomes of failure, primary patency at 30 days, technical success and adverse events (both major and minor). Primary patency at 30 days may improve with surgical compared to mechanical thrombectomy (3 studies, 404 participants: RR 1.36, 95% CI 1.07 to 1.67); however, the evidence is very uncertain. Death, access dysfunction, successful dialysis, and SONG (Standards Outcomes in Nephrology) outcomes were rarely reported. The current review is limited by the small number of available studies with a limited number of patients enrolled. Most of the studies included in this review have a high risk of bias and a low or very low certainty of evidence. Further research is required to define the most effective and clinically appropriate technique for access dysfunction. AUTHORS' CONCLUSIONS: It remains unclear whether any intervention therapy affects the patency at 30 days or failure in any thrombosed HD AV access (very low certainty of evidence). Future research will very likely change the evidence base. Based on the importance of HD access to these patients, future studies of these interventions among people receiving HD should be a priority.

Retrograde distal access versus femoral access for below the knee angioplasty.

BACKGROUND: The prevalence of peripheral artery disease (PAD) in the general population is about 12% to 14% and it increases with age. PAD increased from 164 million people in 2000 to 202 million people in 2010. More than two-thirds of people with PAD are based in low- or middle-income countries. Critical limb ischaemia (CLI) occurs in 1% to 2% of people with intermittent claudication over five years. One third of people with CLI have isolated below the knee (BTK) lesions. CLI and isolated BTK lesions are associated with a higher incidence of limb loss when compared with people with multilevel arterial disease. Endovascular procedures such as angioplasty (with or without stenting) are widely used to treat isolated BTK lesions, aiming to improve blood flow and limb salvage. The technical success of any angioplasty procedure depends on the ability to cross the target lesion. Failed attempts are underestimated in the literature and failures in the real world appear to be higher than reported. People with isolated BTK lesions undergoing angioplasty by conventional femoral access present a high failure rate to cross these lesions. Retrograde distal access may provide some advantages that can lead to successful crossing of the target lesion. OBJECTIVES: To evaluate the benefits and harms of retrograde distal access versus conventional femoral access for people undergoing below the knee angioplasty. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases, and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 26 September 2022. SELECTION CRITERIA: We planned to include randomised or quasi-randomised controlled trials comparing people undergoing retrograde distal access versus people undergoing conventional femoral access (ipsilateral antegrade or contralateral retrograde) for BTK angioplasty. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed identified studies for potential inclusion in the review. We used standard methodological procedures in accordance with the Cochrane Handbook for Systematic Review of Interventions. Our primary outcomes were technical success of angioplasty procedure and major procedural complications. Our secondary outcomes were mortality rate, amputation-free survival, primary patency, minor procedural complications and wound healing. We planned to use GRADE to assess the certainty of the evidence for each outcome. MAIN RESULTS: We identified no randomised or quasi-randomised controlled trials that met the inclusion criteria. AUTHORS' CONCLUSIONS: We identified no randomised or quasi-randomised controlled trials that compared retrograde distal access versus femoral access for BTK angioplasty. High-quality studies that compare retrograde distal access versus conventional femoral access for BTK angioplasty are needed.

Type of anaesthesia for acute ischaemic stroke endovascular treatment.

BACKGROUND: The use of mechanical thrombectomy to restore intracranial blood flow after proximal large artery occlusion by a thrombus has increased over time and led to better outcomes than intravenous thrombolytic therapy alone. Currently, the type of anaesthetic technique during mechanical thrombectomy is under debate as having a relevant impact on neurological outcomes. OBJECTIVES: To assess the effects of different types of anaesthesia for endovascular interventions in people with acute ischaemic stroke. SEARCH METHODS: We searched the Cochrane Stroke Group Specialised Register of Trials on 5 July 2022, and CENTRAL, MEDLINE, and seven other databases on 21 March 2022. We performed searches of reference lists of included trials, grey literature sources, and other systematic reviews.  SELECTION CRITERIA: We included all randomised controlled trials with a parallel design that compared general anaesthesia versus local anaesthesia, conscious sedation anaesthesia, or monitored care anaesthesia for mechanical thrombectomy in acute ischaemic stroke. We also included studies reported as full-text, those published as abstract only, and unpublished data. We excluded quasi-randomised trials, studies without a comparator group, and studies with a retrospective design. DATA COLLECTION AND ANALYSIS: Two review authors independently applied the inclusion criteria, extracted data, and assessed the risk of bias and the certainty of the evidence using the GRADE approach. The outcomes were assessed at different time periods, ranging from the onset of the stroke symptoms to 90 days after the start of the intervention. The main outcomes were functional outcome, neurological impairment, stroke-related mortality, all intracranial haemorrhage, target artery revascularisation status, time to revascularisation, adverse events, and quality of life. All included studies reported data for early (up to 30 days) and long-term (above 30 days) time points. MAIN RESULTS: We included seven trials with 982 participants, which investigated the type of anaesthesia for endovascular treatment in large vessel occlusion in the intracranial circulation. The outcomes were assessed at different time periods, ranging from the onset of stroke symptoms to 90 days after the procedure. Therefore, all included studies reported data for early (up to 30 days) and long-term (above 30 up to 90 days) time points. General anaesthesia versus non-general anaesthesia(early) We are uncertain about the effect of general anaesthesia on functional outcomes compared to non-general anaesthesia (mean difference (MD) 0, 95% confidence interval (CI) -0.31 to 0.31; P = 1.0; 1 study, 90 participants; very low-certainty evidence) and in time to revascularisation from groin puncture until the arterial reperfusion (MD 2.91 minutes, 95% CI -5.11 to 10.92; P = 0.48; I² = 48%; 5 studies, 498 participants; very low-certainty evidence). General anaesthesia may lead to no difference in neurological impairment up to 48 hours after the procedure (MD -0.29, 95% CI -1.18 to 0.59; P = 0.52; I² = 0%; 7 studies, 982 participants; low-certainty evidence), and in stroke-related mortality (risk ratio (RR) 0.98, 95% CI 0.52 to 1.84; P = 0.94; I² = 0%; 3 studies, 330 participants; low-certainty evidence), all intracranial haemorrhages (RR 0.92, 95% CI 0.65 to 1.29; P = 0.63; I² = 0%; 5 studies, 693 participants; low-certainty evidence) compared to non-general anaesthesia. General anaesthesia may improve adverse events (haemodynamic instability) compared to non-general anaesthesia (RR 0.21, 95% CI 0.05 to 0.79; P = 0.02; I² = 71%; 2 studies, 229 participants; low-certainty evidence). General anaesthesia improves target artery revascularisation compared to non-general anaesthesia (RR 1.10, 95% CI 1.02 to 1.18; P = 0.02; I² = 29%; 7 studies, 982 participants; moderate-certainty evidence). There were no available data for quality of life. General anaesthesia versus non-general anaesthesia (long-term) There is no difference in general anaesthesia compared to non-general anaesthesia for dichotomous and continuous functional outcomes (dichotomous: RR 1.21, 95% CI 0.93 to 1.58; P = 0.16; I² = 29%; 4 studies, 625 participants; low-certainty evidence; continuous: MD -0.14, 95% CI -0.34 to 0.06; P = 0.17; I² = 0%; 7 studies, 978 participants; low-certainty evidence). General anaesthesia showed no changes in stroke-related mortality compared to non-general anaesthesia (RR 0.88, 95% CI 0.64 to 1.22; P = 0.44; I² = 12%; 6 studies, 843 participants; low-certainty evidence). There were no available data for neurological impairment, all intracranial haemorrhages, target artery revascularisation status, time to revascularisation from groin puncture until the arterial reperfusion, adverse events (haemodynamic instability), or quality of life. Ongoing studies We identified eight ongoing studies. Five studies compared general anaesthesia versus conscious sedation anaesthesia, one study compared general anaesthesia versus conscious sedation anaesthesia plus local anaesthesia, and two studies compared general anaesthesia versus local anaesthesia. Of these studies, seven plan to report data on functional outcomes using the modified Rankin Scale, five studies on neurological impairment, six studies on stroke-related mortality, two studies on all intracranial haemorrhage, five studies on target artery revascularisation status, four studies on time to revascularisation, and four studies on adverse events. One ongoing study plans to report data on quality of life. One study did not plan to report any outcome of interest for this review. AUTHORS' CONCLUSIONS: In early outcomes, general anaesthesia improves target artery revascularisation compared to non-general anaesthesia with moderate-certainty evidence. General anaesthesia may improve adverse events (haemodynamic instability) compared to non-general anaesthesia with low-certainty evidence. We found no evidence of a difference in neurological impairment, stroke-related mortality, all intracranial haemorrhage and haemodynamic instability adverse events between groups with low-certainty evidence. We are uncertain whether general anaesthesia improves functional outcomes and time to revascularisation because the certainty of the evidence is very low. However, regarding long-term outcomes, general anaesthesia makes no difference to functional outcomes compared to non-general anaesthesia with low-certainty evidence. General anaesthesia did not change stroke-related mortality when compared to non-general anaesthesia with low-certainty evidence. There were no reported data for other outcomes. In view of the limited evidence of effect, more randomised controlled trials with a large number of participants and good protocol design with a low risk of bias should be performed to reduce our uncertainty and to aid decision-making in the choice of anaesthesia.