Interventions for treating catheter-related bloodstream infections in people receiving maintenance haemodialysis.

BACKGROUND: Patients with kidney failure require vascular access to receive maintenance haemodialysis (HD), which can be achieved by an arteriovenous fistula or a central venous catheter (CVC). CVC use is related to frequent complications such as venous stenosis and infection. Venous stenosis occurs mainly due to trauma caused by the entrance of the catheter into the venous lumen and repeated contact with the vein wall.  A biofilm, a colony of irreversible adherent and self-sufficient micro-organisms embedded in a self-produced matrix of exopolysaccharides, is associated with the development of infections in patients with indwelling catheters. Despite its clinical relevance, the treatment of catheter-related bloodstream infections (CRBSIs) in patients receiving maintenance HD remains controversial, especially regarding catheter management. Antibiotic lock solutions may sterilise the catheter, treat the infection and prevent unnecessary catheter procedures. However, such treatment may also lead to antibiotic resistance or even clinical worsening in certain more virulent pathogens. Catheter removal and delayed replacement may remove the source of infection, improving infectious outcomes, but this approach may also increase vascular access stenosis, thrombosis or both, or even central vein access failure. Catheter guidewire exchange attempts to remove the source of infection while maintaining access to the same vein and, therefore, may improve clinical outcomes and preserve central veins for future access. OBJECTIVES: To assess the benefits and harms of different interventions for CRBSI treatment in patients receiving maintenance HD through a permanent CVC, such as systemic antibiotics alone or systemic antibiotics combined with either lock solutions or catheter guidewire exchange or catheter replacement. SEARCH METHODS: We searched the Cochrane Kidney and Transplant Register of Studies up to 21 December 2021 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register were identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov. SELECTION CRITERIA: We included all randomised controlled trials (RCTs) and quasi-RCTs evaluating the management of CRBSI in permanent CVCs in people receiving maintenance HD. DATA COLLECTION AND ANALYSIS: Two authors independently selected studies for inclusion, assessed their risk of bias, and performed data extraction. Results were expressed as risk ratios (RR) or hazard ratios (HR) for dichotomous outcomes and mean difference (MD) for continuous outcomes, with their 95% confidence intervals (CI). The certainty of the evidence was assessed using GRADE. MAIN RESULTS: We identified two RCTs and one quasi-RCT that enrolled 760 participants addressing the treatment of CRBSIs in people (children and adults) receiving maintenance HD through CVC. No two studies compared the same interventions. The quasi-RCT compared two different lock solutions (tissue plasminogen activator (TPA) and heparin) with concurrent systemic antibiotics. One RCT compared systemic antibiotics alone and in association with an ethanol lock solution, and the other compared systemic antibiotics with different catheter management strategies (guidewire exchange versus removal and replacement). The overall certainty of the evidence was downgraded due to the small number of participants, high risk of bias in many domains, especially randomisation, allocation, and other sources of bias, and missing outcome data. It is uncertain whether an ethanol lock solution used with concurrent systemic antibiotics improved CRBSI eradication compared to systemic antibiotics alone (RR 1.61, 95% CI 1.16 to 2.23) because the certainty of this evidence is very low. There were no reported differences between the effects of TPA and heparin lock solutions on cure rates (RR 0.92, 95% CI 0.74 to 1.15) or between catheter guidewire exchange versus catheter removal with delayed replacement, expressed as catheter infection-free survival (HR 0.88, 95% CI 0.43 to 1.79). To date, no results are available comparing other interventions. Outcomes such as venous stenosis and/or thrombosis, antibiotic resistance, death, and adverse events were not reported. AUTHORS' CONCLUSIONS: Currently, there is no available high certainty evidence to support one treatment over another for CRBSIs. The benefit of using ethanol lock treatment in combination with systemic antibiotics compared to systemic antibiotics alone for CRBSIs in patients receiving maintenance HD remains uncertain due to the very low certainty of the evidence. Hence, further RCTs to identify the benefits and harms of CRBSI treatment options are needed. Future studies should unify CRBSI and cure definitions and improve methodological design.

Percutaneous thrombectomy or ultrasound-accelerated thrombolysis for initial management of acute limb ischaemia.

BACKGROUND: Acute limb ischaemia (ALI), the sudden and significant reduction of blood flow to the limb, is considered a vascular emergency. In the general population, the incidence is estimated as 14 per 100,000. Prognosis depends on the time it takes to diagnose the condition and begin appropriate treatment. Standard initial interventional treatments include conventional open surgery and endovascular interventions such as catheter-directed thrombolysis (CDT). Percutaneous interventions, such as percutaneous thrombectomy (PT, including mechanical thrombectomy or pharmomechanical thrombectomy) and ultrasound-accelerated thrombolysis (USAT), are also performed as alternative endovascular techniques. The proposed advantages of PT and USAT include reduced time to revascularisation and when combined with catheter-directed thrombolysis, a reduction in dose of thrombolytic agents and infusion time. The benefits of PT or USAT versus open surgery or thrombolysis alone are still uncertain. In this review, we compared PT or USAT against standard treatment for ALI, in an attempt to determine if any technique is comparatively safer and more effective. OBJECTIVES: To assess the safety and effectiveness of percutaneous thrombectomy or ultrasound-accelerated thrombolysis for the initial management of acute limb ischaemia in adults. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, the World Health Organization (WHO) International Clinical Trials Registry Platform, and ClinicalTrials.gov to 3 March 2021. We searched reference lists of relevant studies and papers. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that compared PT (any modality, including mechanical thrombectomy (aspiration, rheolysis, rotation) or pharmomechanical thrombectomy) or USAT with open surgery, thrombolysis alone, no treatment, or another PT modality for the treatment of ALI. DATA COLLECTION AND ANALYSIS: Two review authors independently selected the studies, assessed risk of bias, extracted data, performed data analysis, and assessed the certainty of evidence according to GRADE. Outcomes of interest were primary patency, amputation rate, major bleeding, clinical success, secondary patency, and adverse effects. MAIN RESULTS: We included one RCT in this review. This study had a total of 60 participants and compared USAT with standard treatment (CDT). The study included 32 participants in the CDT group and 28 participants in the USAT group. We found no evidence of a difference between USAT and CDT alone for the following evaluated outcomes: amputation rate (risk ratio (RR) 1.14, 95% confidence interval (CI) 0.17 to 7.59); major bleeding (RR 1.71, 95% CI 0.31 to 9.53); clinical success (RR 1.00, 95% CI 0.94 to 1.07); and adverse effects (RR 5.69, 95% CI 0.28 to 113.72). We rated the certainty of the evidence as very low for these outcomes. We downgraded the certainty of the evidence for amputation rate, major bleeding, clinical success, and adverse effects by two levels due to serious limitations in the design (there was a high risk of bias in critical domains) and by two further levels due to imprecision (a small number of participants and only one study included). The study authors reported 30-day patency, but did not report primary and secondary patency separately. The patency rate in the successfully lysed participants was 71% (15/21) in the USAT group and 82% (22/27) in the CDT group. The study authors did not directly report secondary patency, which is patency after secondary procedures, but they did report on secondary procedures. Secondary procedures were subdivided into embolectomy and bypass grafting. Embolectomy was performed on 14% (4/28) of participants in the USAT group versus 3% (1/32) of participants in the CDT group. Bypass grafting was performed on 4% (1/28) of participants in the USAT group versus 0% in the CDT group. As we did not have access to the specific participant data, it was not possible to assess these outcomes further. We did not identify studies comparing the other planned interventions. AUTHORS' CONCLUSIONS: There is insufficient evidence to assess the safety and effectiveness of USAT versus CDT alone for ALI for our evaluated outcomes: amputation rate, major bleeding, clinical success, and adverse effects. Primary and secondary patency were not reported separately. There was no RCT evidence for PT. Limitations of this systematic review derive from the single included study, small sample size, short clinical follow-up period, and high risk of bias in critical domains. For this reason, the applicability of the results is limited. There is a need for high-quality studies to compare PT or USAT against open surgery, thrombolysis alone, no treatment, or other PT modalities for ALI. Future trials should assess outcomes, such as primary patency, amputation rate, major bleeding, clinical success, secondary patency, and adverse effects.

Stem cell therapy for treatment of thromboangiitis obliterans (Buerger's disease).

BACKGROUND: Thromboangiitis obliterans, also known as Buerger's disease, is a non-atherosclerotic, segmental inflammatory pathology that most commonly affects the small- and medium-sized arteries, veins, and nerves in the upper and lower extremities. The etiology is unknown, but involves hereditary susceptibility, tobacco exposure, immune and coagulation responses. In many cases, there is no possibility of revascularization to improve the condition. Stem cell therapy is an option for patients with severe complications, such as ischemic ulcers or rest pain. OBJECTIVES: To assess the effectiveness and safety of stem cell therapy in individuals with thromboangiitis obliterans (Buerger's disease). SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 17 October 2017. The review authors searched the European grey literature OpenGrey Database, screened reference lists of relevant studies and contacted study authors. SELECTION CRITERIA: Randomized controlled trials (RCTs) or quasi-RCTs of stem cell therapy in thromboangiitis obliterans (Buerger's disease). DATA COLLECTION AND ANALYSIS: The review authors (DC, DM, FN) independently assessed the studies, extracted data and performed data analysis. MAIN RESULTS: We only included one RCT (18 participants with thromboangiitis obliterans) comparing the implantation of stem cell derived from bone marrow with placebo and standard wound dressing care in this review. We identified no studies that compared stem cell therapy (bone marrow source) versus stem cell therapy (umbilical cord source), stem cell therapy (any source) versus pharmacological treatment and stem cell therapy (any source) versus sympathectomy. Ulcer healing was assessed in the form of ulcer size. The mean ulcer area decreased more in the stem cell implantation group: from 5.04 cm2 (standard deviation (SD) 0.70) to 1.48 cm2 (SD 0.56) compared with the control group: mean ulcer size area decreased from 4.68 cm2 (SD 0.62) to 3.59 cm2 (SD 0.14); mean difference (MD) -2.11 cm2, 95% confidence interval (CI) -2.49 to -1.73; 1 study, 18 participants; very low-quality evidence. Pain-free walking distance showed more of an improvement in the stem cell implantation group: from mean of 38.33 meters (SD 17.68) to 284.44 meters (SD 212.12) compared with the control group: mean walking distance increased from 35.66 meters (SD 19.79) to 78.22 meters (SD 35.35); MD 206.22 meters, 95% CI 65.73 to 346.71; 1 study; 18 participants; very low-quality evidence.Outcomes such as rate of amputation, pain, amputation-free survival and adverse effects were not assessed.The quality of evidence was classified as very low, with only one study, small numbers of participants, high risk of bias in many domains and missing information regarding tobacco exposure status. AUTHORS' CONCLUSIONS: Very low-quality evidence suggests there may be an effect of the use of bone marrow-derived stem cells in the healing of ulcers and improvement in the pain-free walking distance in patients with Buerger's disease. High-quality trials assessing the effectiveness of stem cell therapy for treatment of patients with thromboangiitis obliterans (Buerger's disease) are needed.

Controlled hypotension versus normotensive resuscitation strategy for people with ruptured abdominal aortic aneurysm.

BACKGROUND: An abdominal aortic aneurysm (AAA) is the pathological enlargement of the aorta and can develop in both men and women. Progressive aneurysm enlargement can lead to rupture. The rupture of an AAA is frequently fatal and accounts for the death from haemorrhagic shock of at least 45 people per 100,000 population. The outcome of people with ruptured AAA varies among countries and healthcare systems, with mortality ranging from 53% to 90%. Definitive treatment for ruptured AAA includes open surgery or endovascular repair. The management of haemorrhagic shock is crucial for the person's outcome and aims to restore organ perfusion and systolic blood pressure above 100 mmHg through immediate and aggressive fluid replacement. This rapid fluid replacement is known as the normotensive resuscitation strategy. However, evidence suggests that infusing large volumes of cold fluid causes dilutional and hypothermic coagulopathy. The association of these factors may exacerbate bleeding, resulting in a 'lethal triad' of hypothermia, acidaemia, and coagulopathy. An alternative to the normotensive resuscitation strategy is the controlled (permissive) hypotension resuscitation strategy, with a target systolic blood pressure of 50 mmHg to 100 mmHg. The principle of controlled or hypotensive resuscitation has been used in some management protocols for endovascular repair of ruptured AAA. It may be beneficial in preventing blood loss by avoiding the clot disruption caused by the rapid increase in systolic blood pressure; avoiding dilution of clotting factors, platelets and fibrinogen; and by avoiding the temperature decrease that inhibits enzyme activity involved in platelet and clotting factor function. This is an update of a review first published in 2016. OBJECTIVES: To compare the effects of controlled (permissive) hypotension resuscitation and normotensive resuscitation strategies for people with ruptured AAA. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Specialised Register (August 2017), the Cochrane Register of Studies (CENTRAL (2017, Issue 7)) and EMBASE (August 2017). The Cochrane Vascular Information Specialist also searched clinical trials databases (August 2017) for details of ongoing or unpublished studies. SELECTION CRITERIA: We sought all published and unpublished randomised controlled trial (RCTs) that compared controlled hypotension and normotensive resuscitation strategies for the management of shock in patients with ruptured abdominal aortic aneurysms. 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. MAIN RESULTS: We identified no RCTs that met the inclusion criteria. AUTHORS' CONCLUSIONS: We found no RCTs that compared controlled hypotension and normotensive resuscitation strategies in the management of haemorrhagic shock in patients with ruptured abdominal aortic aneurysm that assessed mortality, presence of coagulopathy, intensive care unit length of stay, and the presence of myocardial infarct and renal failure. High quality studies that evaluate the best strategy for managing haemorrhagic shock in ruptured abdominal aortic aneurysms are required.

Surgical sympathectomy for Buerger's disease.

Buerger's disease is characterized by recurring progressive inflammation and occlusions in small and medium arteries and veins of the limbs. Its cause is unknown, but it is most common in young men with a history of tobacco use. It is responsible for ischemic ulcers and extreme pain in the hands and feet. In many cases, notably in patients with the most severe presentations, there is no possibility of improving the condition with surgery (limb revascularisation), and therefore, alternative therapies (e.g. sympathectomy) is used. This review assessed the effectiveness of surgical sympathectomy compared with any other therapy in patients with Buerger's disease. As a result, only one randomised controlled study (162 participants) compared sympathectomy with prostacyclin analogue (iloprost) was incorporated to the review. Such comparison shown that iloprost is more effective than sympathectomy to complete healing ulcers at four weeks (risk ratio 0.65; 95% confidence interval 0.45 to 0.95; P = 0.02; very low quality evidence) and at twenty four weeks (risk ratio 0.62; 95% confidence interval 0.48 to 0.82; P < 0.01; very low quality evidence) after the start of treatment and to relief rest pain at four weeks (risk ratio 1.90; 95% confidence interval 1.17 to 3.10; P = 0.01; very low quality evidence) but not more effective at twenty four weeks (risk ratio 1.68; 95% confidence interval 1.00 to 2.84; P = .10; very low quality evidence) after the start of treatment. We concluded, with very low quality of evidence, that intravenous iloprost is more effective than lumbar sympathectomyin the healing of ischemic ulcers and pain at rest in patients with Buerger's disease. Therefore, until now, the preference of the usage of intravenous iloprost over the lumbar sympathectomy (and vice versa) does not find robust evidence for its routine use.

Controlled hypotension versus normotensive resuscitation strategy for people with ruptured abdominal aortic aneurysm.

BACKGROUND: An abdominal aortic aneurysm (AAA) is the pathological enlargement of the aorta and can develop in both men and women. Progressive aneurysm enlargement can lead to rupture. The rupture of an AAA is frequently fatal and accounts for the death from haemorrhagic shock of at least 45 people per 100,000 population. The outcome of people with ruptured AAA varies among countries and healthcare systems, with mortality ranging from 53% to 90%. Definitive treatment for ruptured AAA includes open surgery or endovascular repair. The management of haemorrhagic shock is crucial for the person's outcome and aims to restore organ perfusion and systolic blood pressure above 100 mm Hg through immediate and aggressive fluid replacement. This rapid fluid replacement is known as the normotensive resuscitation strategy. However, evidence suggests that infusing large volumes of cold fluid causes dilutional and hypothermic coagulopathy. The association of these factors may exacerbate bleeding, resulting in a 'lethal triad' of hypothermia, acidaemia, and coagulopathy. An alternative to the normotensive resuscitation strategy is the controlled (permissive) hypotension resuscitation strategy, with a target systolic blood pressure of 50 to 100 mm Hg. The principle of controlled or hypotensive resuscitation has been used in some management protocols for endovascular repair of ruptured AAA. It may be beneficial in preventing blood loss by avoiding the clot disruption caused by the rapid increase in systolic blood pressure; avoiding dilution of clotting factors, platelets and fibrinogen; and by avoiding the temperature decrease that inhibits enzyme activity involved in platelet and clotting factor function. OBJECTIVES: To compare the effects of controlled (permissive) hypotension resuscitation and normotensive resuscitation strategies for people with ruptured AAA. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Specialised Register (April 2016) and the Cochrane Register of Studies (CENTRAL (2016, Issue 3)). Clinical trials databases were searched (April 2016) for details of ongoing or unpublished studies. SELECTION CRITERIA: We sought all published and unpublished randomised controlled trial (RCTs) that compared controlled hypotension and normotensive resuscitation strategies for the management of shock in patients with ruptured abdominal aortic aneurysms. 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. MAIN RESULTS: We identified no RCTs that met the inclusion criteria. AUTHORS' CONCLUSIONS: We found no RCTs that compared controlled hypotension and normotensive resuscitation strategies in the management of haemorrhagic shock in patients with ruptured abdominal aortic aneurysm that assessed mortality, presence of coagulopathy, intensive care unit length of stay, and the presence of myocardial infarct and renal failure. High quality studies that evaluate the best strategy for managing haemorrhagic shock in ruptured abdominal aortic aneurysms are required.