Intravenous immunoglobulin for the treatment of Kawasaki disease.

BACKGROUND: Kawasaki disease (KD) is an acute systemic vasculitis (inflammation of the blood vessels) that mainly affects children. Symptoms include fever, chapped lips, strawberry tongue, red eyes (bulbar conjunctival injection), rash, redness, swollen hands and feet or skin peeling; and enlarged cervical lymph nodes. High fevers and systemic inflammation characterise the acute phase. Inflammation of the coronary arteries causes the most serious complication of the disease, coronary artery abnormalities (CAAs). The primary treatment is intravenous immunoglobulin (IVIG) and acetylsalicylic acid (ASA/aspirin), with doses and regimens differing between institutions. It is important to know which regimens are the safest and most effective in preventing complications. OBJECTIVES: To evaluate the efficacy and safety of IVIG in treating and preventing cardiac consequences of Kawasaki disease. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases, and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 26 April 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs) investigating the use of IVIG for the treatment of KD. We included studies involving treatment for initial or refractory KD, or both. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were incidence of CAAs and incidence of any adverse effects after treatment. Our secondary outcomes were acute coronary syndromes, duration of fever, need for additional treatment, length of hospital stay, and mortality. We used GRADE to assess the certainty of the evidence for each outcome. MAIN RESULTS: We identified 31 RCTs involving a total of 4609 participants with KD. Studies compared IVIG with ASA, another dose or regimen of IVIG, prednisolone, or infliximab. The majority of studies reported on primary treatment, so those results are reported below. A limited number of studies investigated secondary or tertiary treatment in IVIG-resistant patients. Doses and regimens of IVIG infusion varied between studies, and all studies had some concerns related to risk of bias. Primary treatment with IVIG compared to ASA for people with KD Compared to ASA treatment, IVIG probably reduces the incidence of CAAs in people with KD up to 30 days (odds ratio (OR) 0.60, 95% confidence interval (CI) 0.41 to 0.87; 11 studies, 1437 participants; moderate-certainty evidence). The individual studies reported a range of adverse effects, but there was little to no difference in numbers of adverse effects between treatment groups (OR 0.57, 95% CI 0.17 to 1.89; 10 studies, 1376 participants; very low-certainty evidence). There was limited evidence for the incidence of acute coronary syndromes, so we are uncertain of any effects. Duration of fever days from treatment onset was probably shorter in the IVIG group (mean difference (MD) -4.00 days, 95% CI -5.06 to -2.93; 3 studies, 307 participants; moderate-certainty evidence). There was little or no difference between groups in need for additional treatment (OR 0.27, 95% CI 0.05 to 1.57; 3 studies, 272 participants; low-certainty evidence). No study reported length of hospital stay, and no deaths were reported in either group. Primary treatment with IVIG compared to different infusion regimens of IVIG for people with KD Higher-dose regimens of IVIG probably reduce the incidence of CAAs compared to medium- or lower-dose regimens of IVIG up to 30 days (OR 0.60, 95% CI 0.40 to 0.89; 8 studies, 1824 participants; moderate-certainty evidence). There was little to no difference in the number of adverse effects between groups (OR 1.11, 95% CI 0.52 to 2.37; 6 studies, 1659 participants; low-certainty evidence). No study reported on acute coronary syndromes. Higher-dose IVIG may reduce the duration of fever compared to medium- or lower-dose regimens (MD -0.71 days, 95% CI -1.36 to -0.06; 4 studies, 992 participants; low-certainty evidence). Higher-dose regimens may reduce the need for additional treatment (OR 0.29, 95% CI 0.10 to 0.88; 4 studies, 1125 participants; low-certainty evidence). We did not detect a clear difference in length of hospital stay between infusion regimens (MD -0.24, 95% CI -0.78 to 0.30; 3 studies, 752 participants; low-certainty evidence). One study reported mortality, and there was little to no difference detected between regimens (moderate-certainty evidence). Primary treatment with IVIG compared to prednisolone for people with KD The evidence comparing IVIG with prednisolone on incidence of CAA is very uncertain (OR 0.60, 95% CI 0.24 to 1.48; 2 studies, 140 participants; very low-certainty evidence), and there was little to no difference between groups in adverse effects (OR 4.18, 95% CI 0.19 to 89.48; 1 study; 90 participants; low-certainty evidence). We are very uncertain of the impact on duration of fever, as two studies reported this outcome differently and showed conflicting results. One study reported on acute coronary syndromes and mortality, finding little or no difference between groups (low-certainty evidence). No study reported the need for additional treatment or length of hospital stay. AUTHORS' CONCLUSIONS: The included RCTs investigated a variety of comparisons, and the small number of events observed during the study periods limited detection of effects. The certainty of the evidence ranged from moderate to very low due to concerns related to risk of bias, imprecision, and inconsistency. The available evidence indicated that high-dose IVIG regimens are probably associated with a reduced risk of CAA formation compared to ASA or medium- or low-dose IVIG regimens. There were no clinically significant differences in incidence of adverse effects, which suggests there is little concern about the safety of IVIG. Compared to ASA, high-dose IVIG probably reduced the duration of fever, but there was little or no difference detected in the need for additional treatment. Compared to medium- or low-dose IVIG, there may be reduced duration of fever and reduced need for additional treatment. We were unable to draw any conclusions regarding acute coronary syndromes, mortality, or length of hospital stay, or for the comparison IVIG versus prednisolone. Our findings are in keeping with current guideline recommendations and evidence from long-term epidemiology studies.

Outpatient versus inpatient treatment for acute pulmonary embolism.

BACKGROUND: Pulmonary embolism (PE) is a common life-threatening cardiovascular condition, with an incidence of 23 to 69 new cases per 100,000 people each year. For selected low-risk patients with acute PE, outpatient treatment might provide several advantages over traditional inpatient treatment, such as reduction of hospitalisations, substantial cost savings, and improvements in health-related quality of life. This is an update of an earlier Cochrane Review. OBJECTIVES: To assess the effects of outpatient versus inpatient treatment in low-risk patients with acute PE. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was 31 May 2021. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of outpatient versus inpatient treatment of adults (aged 18 years and over) diagnosed with low-risk acute PE. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were short- and long-term all-cause mortality. Secondary outcomes were bleeding, adverse effects, recurrence of PE, and patient satisfaction. We used GRADE to assess certainty of evidence for each outcome. MAIN RESULTS: We did not identify any new studies for this update. We included a total of two RCTs involving 453 participants. Both trials discharged participants randomised to the outpatient group within 36 hours of initial triage, and both followed participants for 90 days. One study compared the same treatment regimens in both outpatient and inpatient groups, and the other study used different treatment regimens. There was no clear difference in treatment effect for the outcomes of mortality at 30 days (risk ratio (RR) 0.33, 95% confidence interval (CI) 0.01 to 7.98; 2 studies, 453 participants; low-certainty evidence), mortality at 90 days (RR 0.98, 95% CI 0.06 to 15.58; 2 studies, 451 participants; low-certainty evidence), major bleeding at 14 days (RR 4.91, 95% CI 0.24 to 101.57; 2 studies, 445 participants; low-certainty evidence) and at 90 days (RR 6.88, 95% CI 0.36 to 132.14; 2 studies, 445 participants; low-certainty evidence), minor bleeding (RR 1.08, 95% CI 0.07 to 16.79; 1 study, 106 participants; low-certainty evidence), recurrent PE within 90 days (RR 2.95, 95% CI 0.12 to 71.85; 2 studies, 445 participants; low-certainty evidence), and patient satisfaction (RR 0.97, 95% CI 0.90 to 1.04; 2 studies, 444 participants; moderate-certainty evidence). We downgraded the certainty of the evidence because the CIs were wide and included treatment effects in both directions, the sample sizes and numbers of events were small, and it was not possible to determine the effect of missing data or the presence of publication bias. The included studies did not assess PE-related mortality or adverse effects, such as haemodynamic instability, or adherence to treatment. AUTHORS' CONCLUSIONS: Currently, only low-certainty evidence is available from two published randomised controlled trials on outpatient versus inpatient treatment in low-risk patients with acute PE. The studies did not provide evidence of any clear difference between the interventions in overall mortality, bleeding, or recurrence of PE.

Infusion techniques for peripheral arterial thrombolysis.

BACKGROUND: Acute limb ischaemia usually is caused by a blood clot blocking an artery or a bypass graft. Severe acute ischaemia will lead to irreversible damage to muscles and nerves if blood flow is not restored in a few hours. Once irreversible damage occurs, amputation will be necessary and the condition can be life-threatening. Infusion of clot-busting drugs (thrombolysis) is a useful tool in the management of acute limb ischaemia. Fibrinolytic drugs are used to disperse blood clots (thrombi) to clear arterial occlusion and restore blood flow. Thrombolysis is less invasive than surgery. A variety of techniques are used to deliver fibrinolytic agents. This is an update of a review first published in 2004. OBJECTIVES: To compare the effects of infusion techniques during peripheral arterial thrombolysis for treatment of patients with acute limb ischaemia. 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 registries to 20 October 2020. We undertook reference checking to identify additional studies. SELECTION CRITERIA: We included all randomised controlled trials (RCTs) comparing infusion techniques for fibrinolytic agents in the treatment of acute limb ischaemia. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures as recommended by Cochrane. We assessed the risk of bias in included trials using the Cochrane 'Risk of bias' tool. We evaluated certainty of evidence using GRADE. For dichotomous outcomes, we calculated the odds ratio (OR) with the corresponding 95% confidence interval (CI). We were not able to carry out meta-analyses due to clinical heterogeneity, so we have reported the results and performed the comparisons narratively. The main outcomes of interest were amputation-free survival or limb salvage, amputation, mortality, vessel patency, duration of thrombolysis, and complications such as cerebrovascular accident and major and minor bleeding. MAIN RESULTS: Nine studies with a total of 671 participants are included in this update. Trials covered a variety of infusion techniques, dosage regimens, and adjunctive agents. We grouped trials according to types of techniques assessed (e.g. intravenous and intra-arterial delivery of the agent, 'high-' and 'low-dose' regimens of the agent, continuous infusion and 'forced infusion' of the agent, use of adjunctive antiplatelet agents). We assessed the certainty of evidence as very low to low due to the limited power of individual studies to deliver clinically relevant results, small and heterogeneous study populations, use of different inclusion criteria by each study in terms of severity and duration of ischaemia, considerably different outcome measures between trials, and use of different fibrinolytic agents. This heterogeneity prevented pooling of data in meta-analyses. No regimen has been shown to confer benefit in terms of amputation-free survival (at 30 days), amputation, or death. For vessel patency, complete success was more likely with intra-arterial (IA) than with intravenous (IV) infusion (odds ratio (OR) 13.22, 95% confidence interval (CI) 2.79 to 62.67; 1 study, 40 participants; low-certainty evidence); radiological failure may be more likely with IV infusion (OR 0.02, 95% CI 0.00 to 0.38; 1 study, 40 participants; low-certainty evidence). Due to the small numbers involved in each arm and design differences between arms, it is not possible to conclude whether any technique offered any advantage over another. None of the treatment strategies clearly affected complications such as cerebrovascular accident or major bleeding requiring surgery or blood transfusion. Minor bleeding complications were more frequent in systemic (intravenous) therapy compared to intra-arterial infusion (OR 0.03, 95% CI 0.00 to 0.56; 1 study, 40 participants), and in high-dose compared to low-dose therapy (OR 0.11, 95% CI 0.01 to 0.96; 1 study, 63 participants). Limited evidence from individual trials appears to indicate that high-dose and forced-infusion regimens reduce the duration of thrombolysis. In one trial, the median duration of infusion was 4 hours (range 0.25 to 46) for the high-dose group and 20 hours (range 2 to 46) for the low-dose group. In a second trial, treatment using pulse spray was continued for a median of 120 minutes (range 40 to 310) compared with low-dose infusion for a median of 25 hours (range 2 to 60). In a third trial, the median duration of therapy was reduced with pulse spray at 195 minutes (range 90 to 1260 minutes) compared to continuous infusion at 1390 minutes (range 300 to 2400 minutes). However, none of the studies individually showed improvement in limb salvage at 30 days nor benefit for the amputation rate related to the technique of drug delivery. Similarly, no studies reported a clear difference in occurrence of cerebrovascular accident or major bleeding. Although 'high-dose' and 'forced-infusion' techniques achieved vessel patency in less time than 'low-dose' infusion, more minor bleeding complications may be associated (OR 0.11, 95% CI 0.01 to 0.96; 1 study, 72 participants; and OR 0.48, 95% CI 0.17 to 1.32; 1 study, 121 participants, respectively). Use of adjunctive platelet glycoprotein IIb/IIIa antagonists did not improve outcomes, and results were limited by inclusion of participants with non-limb-threatening ischaemia. AUTHORS' CONCLUSIONS: There is insufficient evidence to show that any thrombolytic regimen provides a benefit over any other in terms of amputation-free survival, amputation, or 30-day mortality. The rate of CVA or major bleeding requiring surgery or blood transfusion did not clearly differ between regimens but may occur more frequently in high dose and IV regimens. This evidence was limited and of very low certainty. Minor bleeding may be more common with high-dose and IV regimens. In this context, thrombolysis may be an acceptable therapy for patients with marginally threatened limbs (Rutherford grade IIa) compared with surgery. Caution is advised for patients who do not have limb-threatening ischaemia (Rutherford grade I) because of risks of major haemorrhage, cerebrovascular accident, and death from thrombolysis.

Effect of testing for cancer on cancer- or venous thromboembolism (VTE)-related mortality and morbidity in people with unprovoked VTE.

BACKGROUND: Venous thromboembolism (VTE) is a collective term for two conditions: deep vein thrombosis (DVT) and pulmonary embolism (PE). A proportion of people with VTE have no underlying or immediately predisposing risk factors and the VTE is referred to as unprovoked. Unprovoked VTE can often be the first clinical manifestation of an underlying malignancy. This has raised the question of whether people with an unprovoked VTE should be investigated for an underlying cancer. Treatment for VTE is different in cancer and non-cancer patients and a correct diagnosis would ensure that people received the optimal treatment for VTE to prevent recurrence and further morbidity. Furthermore, an appropriate cancer diagnosis at an earlier stage could avoid the risk of cancer progression and lead to improvements in cancer-related mortality and morbidity. This is the third update of the review first published in 2015. OBJECTIVES: To determine whether testing for undiagnosed cancer in people with a first episode of unprovoked VTE (DVT of the lower limb or PE) is effective in reducing cancer- or VTE-related mortality and morbidity and to determine which tests for cancer are best at identifying treatable cancers early. 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 5 May 2021. We also undertook reference checking to identify additional studies. SELECTION CRITERIA: Randomised and quasi-randomised trials in which people with an unprovoked VTE were allocated to receive specific tests for identifying cancer or clinically indicated tests only were eligible for inclusion. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, assessed risk of bias and extracted data. We assessed the certainty of the evidence using GRADE criteria. We resolved any disagreements by discussion. The main outcomes of interest were all-cause mortality, cancer-related mortality and VTE-related mortality. MAIN RESULTS: No new studies were identified for this 2021 update. In total, four studies with 1644 participants are included. Two studies assessed the effect of extensive tests including computed tomography (CT) scanning versus tests at the physician's discretion, while the other two studies assessed the effect of standard testing plus positron emission tomography (PET)/CT scanning versus standard testing alone. For extensive tests including CT versus tests at the physician's discretion, the certainty of the evidence, as assessed according to GRADE, was low due to risk of bias (early termination of the studies). When comparing standard testing plus PET/CT scanning versus standard testing alone, the certainty of evidence was moderate due to a risk of detection bias. The certainty of the evidence was downgraded further as detection bias was present in one study with a low number of events. When comparing extensive tests including CT versus tests at the physician's discretion, pooled analysis on two studies showed that testing for cancer was consistent with either benefit or no benefit on cancer-related mortality (odds ratio (OR) 0.49, 95% confidence interval (CI) 0.15 to 1.67; 396 participants; 2 studies; low-certainty evidence). One study (201 participants) showed that, overall, malignancies were less advanced at diagnosis in extensively tested participants than in participants in the control group. In total, 9/13 participants diagnosed with cancer in the extensively tested group had a T1 or T2 stage malignancy compared to 2/10 participants diagnosed with cancer in the control group (OR 5.00, 95% CI 1.05 to 23.76; low-certainty evidence). There was no clear difference in detection of advanced stages between extensive tests versus tests at the physician's discretion: one participant in the extensively tested group had stage T3 compared with four participants in the control group (OR 0.25, 95% CI 0.03 to 2.28; low-certainty evidence). In addition, extensively tested participants were diagnosed earlier than control group (mean: 1 month with extensive tests versus 11.6 months with tests at physician's discretion to cancer diagnosis from the time of diagnosis of VTE). Extensive testing did not increase the frequency of an underlying cancer diagnosis (OR 1.32, 95% CI 0.59 to 2.93; 396 participants; 2 studies; low-certainty evidence). Neither study measured all-cause mortality, VTE-related morbidity and mortality, complications of anticoagulation, adverse effects of cancer tests, participant satisfaction or quality of life. When comparing standard testing plus PET/CT screening versus standard testing alone, standard testing plus PET/CT screening was consistent with either benefit or no benefit on all-cause mortality (OR 1.22, 95% CI 0.49 to 3.04; 1248 participants; 2 studies; moderate-certainty evidence), cancer-related mortality (OR 0.55, 95% CI 0.20 to 1.52; 1248 participants; 2 studies; moderate-certainty evidence) or VTE-related morbidity (OR 1.02, 95% CI 0.48 to 2.17; 854 participants; 1 study; moderate-certainty evidence). Regarding stage of cancer, there was no clear difference for detection of early (OR 1.78, 95% 0.51 to 6.17; 394 participants; 1 study; low-certainty evidence) or advanced (OR 1.00, 95% CI 0.14 to 7.17; 394 participants; 1 study; low-certainty evidence) stages of cancer. There was also no clear difference in the frequency of an underlying cancer diagnosis (OR 1.71, 95% CI 0.91 to 3.20; 1248 participants; 2 studies; moderate-certainty evidence). Time to cancer diagnosis was 4.2 months in the standard testing group and 4.0 months in the standard testing plus PET/CT group (P = 0.88). Neither study measured VTE-related mortality, complications of anticoagulation, adverse effects of cancer tests, participant satisfaction or quality of life. AUTHORS' CONCLUSIONS: Specific testing for cancer in people with unprovoked VTE may lead to earlier diagnosis of cancer at an earlier stage of the disease. However, there is currently insufficient evidence to draw definitive conclusions concerning the effectiveness of testing for undiagnosed cancer in people with a first episode of unprovoked VTE (DVT or PE) in reducing cancer- or VTE-related morbidity and mortality. The results could be consistent with either benefit or no benefit. Further good-quality large-scale randomised controlled trials are required before firm conclusions can be made.

Compression stockings for preventing deep vein thrombosis in airline passengers.

BACKGROUND: Air travel might increase the risk of deep vein thrombosis (DVT). It has been suggested that wearing compression stockings might reduce this risk. This is an update of the review first published in 2006. OBJECTIVES: To assess the effects of wearing compression stockings versus not wearing them for preventing DVT in people travelling on flights lasting at least four hours. 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 1 April 2020. We also checked the bibliographies of relevant studies and reviews identified by the search to check for any additional trials. SELECTION CRITERIA: Randomised trials of compression stockings versus no stockings in passengers on flights lasting at least four hours. Trials in which passengers wore a stocking on one leg but not the other, or those comparing stockings and another intervention were also eligible. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion and extracted data. We sought additional information from trialists where necessary. MAIN RESULTS: One new study that fulfilled the inclusion criteria was identified for this update. Twelve randomised trials (n = 2918) were included in this review: ten (n = 2833) compared wearing graduated compression stockings on both legs versus not wearing them; one trial (n = 50) compared wearing graduated compression tights versus not wearing them; and one trial (n = 35) compared wearing a graduated compression stocking on one leg for the outbound flight and on the other leg on the return flight. Eight trials included people judged to be at low or medium risk of developing DVT (n = 1598) and two included high-risk participants (n = 1273). All flights had a duration of more than five hours. Fifty of 2637 participants with follow-up data available in the trials of wearing compression stockings on both legs had a symptomless DVT; three wore stockings, 47 did not (odds ratio (OR) 0.10, 95% confidence interval (CI) 0.04 to 0.25, P < 0.001; high-certainty evidence). There were no symptomless DVTs in three trials. Sixteen of 1804 people developed superficial vein thrombosis, four wore stockings, 12 did not (OR 0.45, 95% CI 0.18 to 1.13, P = 0.09; moderate-certainty evidence). No deaths, pulmonary emboli or symptomatic DVTs were reported. Wearing stockings had a significant impact in reducing oedema (mean difference (MD) -4.72, 95% CI -4.91 to -4.52; based on six trials; low-certainty evidence). A further three trials showed reduced oedema in the stockings group but could not be included in the meta-analysis as they used different methods to measure oedema. No significant adverse effects were reported. AUTHORS' CONCLUSIONS: There is high-certainty evidence that airline passengers similar to those in this review can expect a substantial reduction in the incidence of symptomless DVT and low-certainty evidence that leg oedema is reduced if they wear compression stockings. The certainty of the evidence was limited by the way that oedema was measured. There is moderate-certainty evidence that superficial vein thrombosis may be reduced if passengers wear compression stockings. We cannot assess the effect of wearing stockings on death, pulmonary embolism or symptomatic DVT because no such events occurred in these trials. Randomised trials to assess these outcomes would need to include a very large number of people.

Thrombolytic strategies versus standard anticoagulation for acute deep vein thrombosis of the lower limb.

BACKGROUND: Standard treatment for deep vein thrombosis (DVT) aims to reduce immediate complications. Use of thrombolytic clot removal strategies (i.e. thrombolysis (clot dissolving drugs), with or without additional endovascular techniques), could reduce the long-term complications of post-thrombotic syndrome (PTS) including pain, swelling, skin discolouration, or venous ulceration in the affected leg. This is the fourth update of a Cochrane Review first published in 2004. OBJECTIVES: To assess the effects of thrombolytic clot removal strategies and anticoagulation compared to anticoagulation alone for the management of people with acute deep vein thrombosis (DVT) of the lower limb. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registries to 21 April 2020. We also checked the references of relevant articles to identify additional studies. SELECTION CRITERIA: We considered randomised controlled trials (RCTs) examining thrombolysis (with or without adjunctive clot removal strategies) and anticoagulation versus anticoagulation alone for acute DVT. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures as recommended by Cochrane. We assessed the risk of bias in included trials with the Cochrane 'Risk of bias' tool. Certainty of the evidence was evaluated using GRADE. For dichotomous outcomes, we calculated the risk ratio (RR) with the corresponding 95% confidence interval (CI). We pooled data using a fixed-effect model, unless we identified heterogeneity, in which case we used a random-effects model. The primary outcomes of interest were clot lysis, bleeding and post thrombotic syndrome. MAIN RESULTS: Two new studies were added for this update. Therefore, the review now includes a total of 19 RCTs, with 1943 participants. These studies differed with respect to the thrombolytic agent, the doses of the agent and the techniques used to deliver the agent. Systemic, loco-regional and catheter-directed thrombolysis (CDT) strategies were all included. For this update, CDT interventions also included those involving pharmacomechanical thrombolysis. Three of the 19 included studies reported one or more domain at high risk of bias. We combined the results as any (all) thrombolysis interventions compared to standard anticoagulation. Complete clot lysis occurred more frequently in the thrombolysis group at early follow-up (RR 4.75; 95% CI 1.83 to 12.33; 592 participants; eight studies) and at intermediate follow-up (RR 2.42; 95% CI 1.42 to 4.12; 654 participants; seven studies; moderate-certainty evidence). Two studies reported on clot lysis at late follow-up with no clear benefit from thrombolysis seen at this time point (RR 3.25, 95% CI 0.17 to 62.63; two studies). No differences between strategies (e.g. systemic, loco-regional and CDT) were detected by subgroup analysis at any of these time points (tests for subgroup differences: P = 0.41, P = 0.37 and P = 0.06 respectively). Those receiving thrombolysis had increased bleeding complications (6.7% versus 2.2%) (RR 2.45, 95% CI 1.58 to 3.78; 1943 participants, 19 studies; moderate-certainty evidence). No differences between strategies were detected by subgroup analysis (P = 0.25). Up to five years after treatment, slightly fewer cases of PTS occurred in those receiving thrombolysis; 50% compared with 53% in the standard anticoagulation (RR 0.78, 95% CI 0.66 to 0.93; 1393 participants, six studies; moderate-certainty evidence). This was still observed at late follow-up (beyond five years) in two studies (RR 0.56, 95% CI 0.43 to 0.73; 211 participants; moderate-certainty evidence). We used subgroup analysis to investigate if the level of DVT (iliofemoral, femoropopliteal or non-specified) had an effect on the incidence of PTS. No benefit of thrombolysis was seen for either iliofemoral or femoropopliteal DVT (six studies; test for subgroup differences: P = 0.29). Systemic thrombolysis and CDT had similar levels of effectiveness. Studies of CDT included four trials in femoral and iliofemoral DVT, and results from these are consistent with those from trials of systemic thrombolysis in DVT at other levels of occlusion. AUTHORS' CONCLUSIONS: Complete clot lysis occurred more frequently after thrombolysis (with or without additional clot removal strategies) and PTS incidence was slightly reduced. Bleeding complications also increased with thrombolysis, but this risk has decreased over time with the use of stricter exclusion criteria of studies. Evidence suggests that systemic administration of thrombolytics and CDT have similar effectiveness. Using GRADE, we judged the evidence to be of moderate-certainty, due to many trials having small numbers of participants or events, or both. Future studies are needed to investigate treatment regimes in terms of agent, dose and adjunctive clot removal methods; prioritising patient-important outcomes, including PTS and quality of life, to aid clinical decision making.

Pentoxifylline for intermittent claudication.

BACKGROUND: Intermittent claudication (IC) is a symptom of peripheral arterial disease (PAD) and is associated with high morbidity and mortality. Pentoxifylline, one of many drugs used to treat IC, acts by decreasing blood viscosity, improving erythrocyte flexibility, and promoting microcirculatory flow and tissue oxygen concentration. Many studies have evaluated the efficacy of pentoxifylline in treating people with PAD, but results of these studies are variable. This is the second update of a review first published in 2012. OBJECTIVES: To determine the efficacy of pentoxifylline in improving the walking capacity (i.e. pain-free walking distance and total (absolute, maximum) walking distance) of people with stable intermittent claudication, Fontaine stage II. SEARCH METHODS: For this update, 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 28 January 2020. There were no language restrictions. SELECTION CRITERIA: We included all double-blind, randomised controlled trials (RCTs) comparing pentoxifylline versus placebo or any other pharmacological intervention in people with IC Fontaine stage II. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies for inclusion, assessed the included studies, matched data and resolved disagreements by discussion. Review authors assessed the methodological quality of studies using the Cochrane 'Risk of bias' tool and collected results related to the outcomes of interest, pain-free walking distance (PFWD), total walking distance (TWD), ankle-brachial pressure index (ABI), quality of life (QoL) and side effects. Comparison of studies was based on duration and dose of pentoxifylline. We used GRADE criteria to assess the certainty of the evidence. MAIN RESULTS: We identified no new eligible studies for this update. This review includes 24 studies with 3377 participants. Seventeen studies compared pentoxifylline versus placebo. The seven remaining studies compared pentoxifylline with flunarizine (one study), aspirin (one study), Gingko biloba extract (one study), nylidrin hydrochloride (one study), prostaglandin E1 (two studies), and buflomedil and nifedipine (one study). Risk of bias for the individual studies was generally unclear because there was a lack of methodological reporting for many of the included studies, especially regarding randomisation and allocation methods. Most included studies did not provide adequate information to allow selective reporting to be judged and did not report blinding of assessors. Heterogeneity between included studies was considerable with regards to multiple variables, including duration of treatment, dose of pentoxifylline, baseline walking distance and participant characteristics; therefore, pooled analysis for comparisons which included more than one study, was not possible. Pentoxifylline compared to placebo Of 17 studies comparing pentoxifylline with placebo, 11 reported PFWD and 14 reported TWD; the difference in percentage improvement in PFWD for pentoxifylline over placebo ranged from -33.8% to 73.9% and in TWD ranged from 1.2% to 155.9%. It was not possible to pool the data of the studies because data were insufficient and findings from individual trials were unclear. Most included studies suggested a possible improvement in PFWD and TWD for pentoxifylline over placebo (both low-certainty evidence). The five studies which evaluated pre-exercise ABI comparing pentoxifylline and placebo found no evidence of a difference (moderate-certainty evidence). Two of the three studies that evaluated QoL between people who received pentoxifylline and placebo were larger studies that used validated QoL tools and generally found no evidence of a difference between groups. One small, short-term study, which did not specify which QoL tool was used, reported improved QoL in the pentoxifylline group (moderate-certainty evidence). Pentoxifylline generally was well tolerated; the most commonly reported side effects consisted of gastrointestinal symptoms such as nausea (low-certainty evidence). Certainty of the evidence from this review was low or moderate, with downgrading due to risk of bias concerns, inconsistencies between studies and the inability to evaluate imprecision because meta-analysis could not be undertaken. The seven remaining studies compared pentoxifylline with either flunarizine, aspirin, Gingko biloba extract, nylidrin hydrochloride, prostaglandin E1, or buflomedil and nifedipine; data were too limited to allow any meaningful conclusions to be made. AUTHORS' CONCLUSIONS: There is a lack of high-certainty evidence for the effects of pentoxifylline compared to placebo, or other treatments, for IC. There is low-certainty evidence that pentoxifylline may improve PFWD and TWD compared to placebo, but no evidence of a benefit to ABI or QoL (moderate-certainty evidence). Pentoxifylline was reported to be generally well tolerated (low-certainty evidence). Given the large degree of heterogeneity between the studies, the role of pentoxifylline for people with IC Fontaine class II remains uncertain.

Dressings and topical agents for arterial leg ulcers.

BACKGROUND: It is estimated that up to 1% of people in high-income countries suffer from a leg ulcer at some time in their life. The majority of leg ulcers are associated with circulation problems; poor blood return in the veins causes venous ulcers (around 70% of ulcers) and poor blood supply to the legs causes arterial ulcers (around 22% of ulcers). Treatment of arterial leg ulcers is directed towards correcting poor arterial blood supply, for example by correcting arterial blockages (either surgically or pharmaceutically). If the blood supply has been restored, these arterial ulcers can heal following principles of good wound-care. Dressings and topical agents make up a part of good wound-care for arterial ulcers, but there are many products available, and it is unclear what impact these have on ulcer healing. This is the third update of a review first published in 2003. OBJECTIVES: To determine whether topical agents and wound dressings affect healing in arterial ulcers. To compare healing rates and patient-centred outcomes between wound dressings and topical agents. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, Cochrane Central Register of Controlled Trials, MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature and Allied and Complementary Medicine databases, the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials register to 28 January 2019. SELECTION CRITERIA: Randomised controlled trials (RCTs), or controlled clinical trials (CCTs) evaluating dressings and topical agents in the treatment of arterial leg ulcers were eligible for inclusion. We included participants with arterial leg ulcers irrespective of method of diagnosis. Trials that included participants with mixed arterio-venous disease and diabetes were eligible for inclusion if they presented results separately for the different groups. All wound dressings and topical agents were eligible for inclusion in this review. We excluded trials which did not report on at least one of the primary outcomes (time to healing, proportion completely healed, or change in ulcer area). DATA COLLECTION AND ANALYSIS: Two review authors independently extracted information on the participants' characteristics, the interventions, and outcomes using a standardised data extraction form. Review authors resolved any disagreements through discussion. We presented the data narratively due to differences in the included trials. We used GRADE to assess the certainty of the evidence. MAIN RESULTS: Two trials met the inclusion criteria. One compared 2% ketanserin ointment in polyethylene glycol (PEG) with PEG alone, used twice a day by 40 participants with arterial leg ulcers, for eight weeks or until healing, whichever was sooner. One compared topical application of blood-derived concentrated growth factor (CGF) with standard dressing (polyurethane film or foam); both applied weekly for six weeks by 61 participants with non-healing ulcers (venous, diabetic arterial, neuropathic, traumatic, or vasculitic). Both trials were small, reported results inadequately, and were of low methodological quality. Short follow-up times (six and eight weeks) meant it would be difficult to capture sufficient healing events to allow us to make comparisons between treatments. One trial demonstrated accelerated wound healing in the ketanserin group compared with the control group. In the trial that compared CGF with standard dressings, the number of participants with diabetic arterial ulcers were only reported in the CGF group (9/31), and the number of participants with diabetic arterial ulcers and their data were not reported separately for the standard dressing group. In the CGF group, 66.6% (6/9) of diabetic arterial ulcers showed more than a 50% decrease in ulcer size compared to 6.7% (2/30) of non-healing ulcers treated with standard dressing. We assessed this as very-low certainty evidence due to the small number of studies and arterial ulcer participants, inadequate reporting of methodology and data, and short follow-up period. Only one trial reported side effects (complications), stating that no participant experienced these during follow-up (six weeks, low-certainty evidence). It should also be noted that ketanserin is not licensed in all countries for use in humans. Neither study reported time to ulcer healing, patient satisfaction or quality of life. AUTHORS' CONCLUSIONS: There is insufficient evidence to determine whether the choice of topical agent or dressing affects the healing of arterial leg ulcers.

Outpatient versus inpatient treatment for acute pulmonary embolism.

BACKGROUND: Pulmonary embolism (PE) is a common life-threatening cardiovascular condition, with an incidence of 23 to 69 new cases per 100,000 people each year. For selected low-risk patients with acute PE, outpatient treatment might provide several advantages over traditional inpatient treatment, such as reduction of hospitalisations, substantial cost savings, and improvements in health-related quality of life. This is an update of the review first published in 2014. OBJECTIVES: To compare the efficacy and safety of outpatient versus inpatient treatment in low-risk patients with acute PE for the outcomes of all-cause and PE-related mortality; bleeding; adverse events such as haemodynamic instability; recurrence of PE; and patients' satisfaction. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases, and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers, to 26 March 2018. We also undertook reference checking to identify additional studies. SELECTION CRITERIA: We included randomised controlled trials of outpatient versus inpatient treatment of adults (aged 18 years and over) diagnosed with low-risk acute PE. DATA COLLECTION AND ANALYSIS: Two review authors selected relevant trials, assessed methodological quality, and extracted and analysed data. We calculated effect estimates using risk ratio (RR) with 95% confidence intervals (CIs), or mean differences (MDs) with 95% CIs. We used standardised mean differences (SMDs) to combine trials that measured the same outcome but used different methods. We assessed the quality of the evidence using GRADE criteria. MAIN RESULTS: One new study was identified for this 2018 update, bringing the total number of included studies to two and the total number of participants to 451. Both trials discharged patients randomised to the outpatient group within 36 hours of initial triage and both followed participants for 90 days. One study compared the same treatment regimens in both outpatient and inpatient groups, and the other study used different treatment regimes. There was no clear difference in treatment effect for the outcomes of short-term mortality (30 days) (RR 0.33, 95% CI 0.01 to 7.98, P = 0.49; low-quality evidence), long-term mortality (90 days) (RR 0.98, 95% CI 0.06 to 15.58, P = 0.99, low-quality evidence), major bleeding at 14 days (RR 4.91, 95% CI 0.24 to 101.57, P = 0.30; low-quality evidence) and at 90 days (RR 6.88, 95% CI 0.36 to 132.14, P = 0.20; low-quality evidence), minor bleeding (RR 1.08, 95% CI 0.07 to 16.79; P = 0.96, low-quality evidence), recurrent PE within 90 days (RR 2.95, 95% CI 0.12 to 71.85, P = 0.51, low-quality evidence), and participant satisfaction (RR 0.97, 95% CI 0.90 to 1.04, P = 0.39; moderate-quality evidence). We downgraded the quality of the evidence because the CIs were wide and included treatment effects in both directions, the sample sizes and numbers of events were small, and because the effect of missing data and the absence of publication bias could not be verified. PE-related mortality, and adverse effects such as haemodynamic instability and compliance, were not assessed by the included studies. AUTHORS' CONCLUSIONS: Currently, only low-quality evidence is available from two published randomised controlled trials on outpatient versus inpatient treatment in low-risk patients with acute PE. The studies did not provide evidence of any clear difference between the interventions in overall mortality, bleeding and recurrence of PE.

Rutosides for treatment of post-thrombotic syndrome.

BACKGROUND: Post-thrombotic syndrome (PTS) is a long-term complication of deep venous thrombosis (DVT) that is characterised by pain, swelling, and skin changes in the affected limb. One in three patients with DVT will develop post-thrombotic sequelae within five years. Rutosides are a group of compounds derived from horse chestnut (Aesculus hippocastanum), a traditional herbal remedy for treating oedema formation in chronic venous insufficiency (CVI). However, it is not known whether rutosides are effective and safe in the treatment of PTS. This is the second update of the review first published in 2013. OBJECTIVES: To determine the effectiveness (improvement or deterioration in symptoms) and safety of rutosides for treatment of post-thrombotic syndrome (PTS) in patients with DVT compared to placebo, no intervention, elastic compression stockings (ECS) or any other treatment. 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 21 August 2018. SELECTION CRITERIA: Two review authors independently assessed studies for inclusion. Studies were included to allow the comparison of rutosides versus placebo or no treatment, rutosides versus ECS, and rutosides versus any other treatment. Two review authors extracted information from the trials. Disagreements were resolved by discussion. DATA COLLECTION AND ANALYSIS: Data were extracted using designated data extraction forms. The Cochrane 'Risk of bias' tool was used for all included studies to assist in the assessment of quality. Primary outcome measures were the occurrence of leg ulceration over time (yes or no) and any improvement or deterioration of post-thrombotic syndrome (yes or no). Secondary outcomes included reduction of oedema, pain, recurrence of DVT or pulmonary embolism, compliance with therapy, and adverse effects. All of the outcome measures were analysed using Mantel-Haenzel fixed-effect model odds ratios. The unit of analysis was the number of patients. We used GRADE to assess the quality of the evidence for each outcome. MAIN RESULTS: Ten reports of nine studies were identified following searching and three studies with a total of 233 participants met the inclusion criteria. Overall quality of evidence using the GRADE approach was low, predominantly due to the lack of both participant and researcher blinding in the included studies. The quality of the evidence was further limited as only three small studies contributed to the review findings. A subjective scoring system was used to obtain the symptoms of PTS so it was important that the assessors were blinded to the intervention. One study compared rutosides with placebo, one study compared rutosides with ECS and rutosides plus ECS versus ECS alone, and one study compared rutosides with an alternative venoactive remedy. Occurrence of leg ulceration was not reported in any of the included studies. There was no clear evidence to support a difference in PTS improvement between the rutosides or placebo/no treatment groups (OR 1.29, 95% CI 0.69 to 2.41; 164 participants; 2 studies; low-quality evidence); or between the rutosides and ECS groups (OR 0.80, 95% CI 0.31 to 2.03; 80 participants; 1 study ; low-quality evidence). Results from one small study reported less PTS improvement in the rutosides group compared to an alternative venoactive remedy (OR 0.18, 95% CI 0.04 to 0.94; 29 participants; 1 study; low-quality evidence). There was no clear evidence to support a difference in PTS deterioration when comparing rutosides with placebo/no treatment (OR 0.61, 95% CI 0.19 to 1.90; 80 participants; 1 study); with ECS (OR 0.61, 95% CI 0.19 to 1.90; 80 participants; 1 study); or an alternative venoactive remedy (OR 0.19, 95% CI 0.01 to 4.24; 29 participants; 1 study). No clear evidence of a difference in adverse effects between the rutosides and placebo/no treatment groups was seen ('mild side effects' reported in 7/41 and 5/42 respectively). In the study comparing rutosides with ECS, 2/80 could not tolerate ECS and 6/80 stopped medication due to side effects. The study comparing rutosides with an alternative venoactive remedy did not comment on side effects AUTHORS' CONCLUSIONS: There was no evidence that rutosides were superior to the use of placebo or ECS. Overall, there is currently limited low-quality evidence that 'venoactive' or 'phlebotonic' remedies such as rutosides reduce symptoms of PTS. Mild side effects were noted in one study. The three studies included in this review provide no evidence to support the use of rutosides in the treatment of PTS.

Effect of testing for cancer on cancer- or venous thromboembolism (VTE)-related mortality and morbidity in people with unprovoked VTE.

BACKGROUND: Venous thromboembolism (VTE) is a collective term for two conditions: deep vein thrombosis (DVT) and pulmonary embolism (PE). A proportion of people with VTE have no underlying or immediately predisposing risk factors and the VTE is referred to as unprovoked. Unprovoked VTE can often be the first clinical manifestation of an underlying malignancy. This has raised the question of whether people with an unprovoked VTE should be investigated for an underlying cancer. Treatment for VTE is different in cancer and non-cancer patients and a correct diagnosis would ensure that people received the optimal treatment for VTE to prevent recurrence and further morbidity. Furthermore, an appropriate cancer diagnosis at an earlier stage could avoid the risk of cancer progression and lead to improvements in cancer-related mortality and morbidity. This is an update of a review first published in 2015. OBJECTIVES: To determine whether testing for undiagnosed cancer in people with a first episode of unprovoked VTE (DVT of the lower limb or PE) is effective in reducing cancer or VTE-related mortality and morbidity and to determine which tests for cancer are best at identifying treatable cancers early. 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 11 July 2018. We also undertook reference checking to identify additional studies. SELECTION CRITERIA: Randomised and quasi-randomised trials in which people with an unprovoked VTE were allocated to receive specific tests for identifying cancer or clinically indicated tests only were eligible for inclusion. Primary outcomes included all-cause mortality, cancer-related mortality and VTE-related mortality. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, assessed risk of bias and extracted data. We resolved any disagreements by discussion. MAIN RESULTS: No new studies were identified for this 2018 update. In total, four studies with 1644 participants are included. Two studies assessed the effect of extensive tests including computed tomography (CT) scanning versus tests at the physician's discretion, while the other two studies assessed the effect of standard testing plus positron emission tomography (PET)/CT scanning versus standard testing alone. For extensive tests including CT versus tests at the physician's discretion, the quality of the evidence, as assessed according to GRADE, was low due to risk of bias (early termination of the studies). When comparing standard testing plus PET/CT scanning versus standard testing alone, the quality of evidence was moderate due to a risk of detection bias. The quality of the evidence was downgraded further as detection bias was present in one study with a low number of events.When comparing extensive tests including CT versus tests at the physician's discretion, pooled analysis on two studies showed that testing for cancer was consistent with either benefit or no benefit on cancer-related mortality (odds ratio (OR) 0.49, 95% confidence interval (CI) 0.15 to 1.67; 396 participants; 2 studies; P = 0.26; low-quality evidence). One study (201 participants) showed that, overall, malignancies were less advanced at diagnosis in extensively tested participants than in participants in the control group. In total, 9/13 participants diagnosed with cancer in the extensively tested group had a T1 or T2 stage malignancy compared to 2/10 participants diagnosed with cancer in the control group (OR 5.00, 95% CI 1.05 to 23.76; P = 0.04; low-quality evidence). There was no clear difference in detection of advanced stages between extensive tests versus tests at the physician's discretion: one participant in the extensively tested group had stage T3 compared with four participants in the control group (OR 0.25, 95% CI 0.03 to 2.28; P = 0.22; low-quality evidence). In addition, extensively tested participants were diagnosed earlier than control group (mean: 1 month with extensive tests versus 11.6 months with tests at physician's discretion to cancer diagnosis from the time of diagnosis of VTE). Extensive testing did not increase the frequency of an underlying cancer diagnosis (OR 1.32, 95% CI 0.59 to 2.93; 396 participants; 2 studies; P = 0.50; low-quality evidence). Neither study measured all-cause mortality, VTE-related morbidity and mortality, complications of anticoagulation, adverse effects of cancer tests, participant satisfaction or quality of life.When comparing standard testing plus PET/CT screening versus standard testing alone, standard testing plus PET/CT screening was consistent with either benefit or no benefit on all-cause mortality (OR 1.22, 95% CI 0.49 to 3.04; 1248 participants; 2 studies; P = 0.66; moderate-quality evidence), cancer-related mortality (OR 0.55, 95% CI 0.20 to 1.52; 1248 participants; 2 studies; P = 0.25; moderate-quality evidence) or VTE-related morbidity (OR 1.02, 95% CI 0.48 to 2.17; 854 participants; 1 study; P = 0.96; moderate-quality evidence). Regarding stage of cancer, there was no clear difference for detection of early (OR 1.78, 95% 0.51 to 6.17; 394 participants; 1 study; P = 0.37; low-quality evidence) or advanced (OR 1.00, 95% CI 0.14 to 7.17; 394 participants; 1 study; P = 1.00; low-quality evidence) stages of cancer. There was also no clear difference in the frequency of an underlying cancer diagnosis (OR 1.71, 95% CI 0.91 to 3.20; 1248 participants; 2 studies; P = 0.09; moderate-quality evidence). Time to cancer diagnosis was 4.2 months in the standard testing group and 4.0 months in the standard testing plus PET/CT group (P = 0.88). Neither study measured VTE-related mortality, complications of anticoagulation, adverse effects of cancer tests, participant satisfaction or quality of life. AUTHORS' CONCLUSIONS: Specific testing for cancer in people with unprovoked VTE may lead to earlier diagnosis of cancer at an earlier stage of the disease. However, there is currently insufficient evidence to draw definitive conclusions concerning the effectiveness of testing for undiagnosed cancer in people with a first episode of unprovoked VTE (DVT or PE) in reducing cancer- or VTE-related morbidity and mortality. The results could be consistent with either benefit or no benefit. Further good-quality large-scale randomised controlled trials are required before firm conclusions can be made.

Thrombolysis for acute deep vein thrombosis.

BACKGROUND: Standard treatment for deep vein thrombosis aims to reduce immediate complications. Use of thrombolysis or clot dissolving drugs could reduce the long-term complications of post-thrombotic syndrome (PTS) including pain, swelling, skin discolouration, or venous ulceration in the affected leg. This is the third update of a review first published in 2004. OBJECTIVES: To assess the effects of thrombolytic therapy and anticoagulation compared to anticoagulation alone for the management of people with acute deep vein thrombosis (DVT) of the lower limb as determined by the effects on pulmonary embolism, recurrent venous thromboembolism, major bleeding, post-thrombotic complications, venous patency and venous function. SEARCH METHODS: For this update the Cochrane Vascular Information Specialist (CIS) searched the Specialised Register (February 2016). In addition the CIS searched the Cochrane Register of Studies (CENTRAL (2016, Issue 1)). Trial registries were searched for details of ongoing or unpublished studies. SELECTION CRITERIA: Randomised controlled trials (RCTs) examining thrombolysis and anticoagulation versus anticoagulation for acute DVT were considered. DATA COLLECTION AND ANALYSIS: For this update (2016), LW and CB selected trials, extracted data independently, and sought advice from MPA where necessary. We assessed study quality with the Cochrane risk of bias tool. For dichotomous outcomes, we calculated the risk ratio (RR) and corresponding 95% confidence interval (CI). Data were pooled using a fixed-effect model unless significant heterogeneity was identified in which case a random-effects model was used. GRADE was used to assess the overall quality of the evidence supporting the outcomes assessed in this review. MAIN RESULTS: Seventeen RCTs with 1103 participants were included. These studies differed in the both thrombolytic agent used and in the technique used to deliver it. Systemic, loco-regional and catheter-directed thrombolysis (CDT) were all included. Fourteen studies were rated as low risk of bias and three studies were rated as high risk of bias. We combined the results as any (all) thrombolysis compared to standard anticoagulation. Complete clot lysis occurred significantly more often in the treatment group at early follow-up (RR 4.91; 95% CI 1.66 to 14.53, P = 0.004) and at intermediate follow-up (RR 2.44; 95% CI 1.40 to 4.27, P = 0.002; moderate quality evidence). A similar effect was seen for any degree of improvement in venous patency. Up to five years after treatment significantly less PTS occurred in those receiving thrombolysis (RR 0.66, 95% CI 0.53 to 0.81; P < 0.0001; moderate quality evidence). This reduction in PTS was still observed at late follow-up (beyond five years), in two studies (RR 0.58, 95% CI 0.45 to 0.77; P < 0.0001; moderate quality evidence). Leg ulceration was reduced although the data were limited by small numbers (RR 0.87; 95% CI 0.16 to 4.73, P = 0.87). Those receiving thrombolysis had increased bleeding complications (RR 2.23; 95% CI 1.41 to 3.52, P = 0.0006; moderate quality evidence). Three strokes occurred in the treatment group, all in trials conducted pre-1990, and none in the control group. There was no significant effect on mortality detected at either early or intermediate follow-up. Data on the occurrence of pulmonary embolism (PE) and recurrent DVT were inconclusive. Systemic thrombolysis and CDT had similar levels of effectiveness. Studies of CDT included two trials in femoral and iliofemoral DVT, and results from these are consistent with those from trials of systemic thrombolysis in DVT at other levels of occlusion. AUTHORS' CONCLUSIONS: Thrombolysis increases the patency of veins and reduces the incidence of PTS following proximal DVT by a third. Evidence suggests that systemic administration and CDT have similar effectiveness. Strict eligibility criteria appears to improve safety in recent studies and may be necessary to reduce the risk of bleeding complications. This may limit the applicability of this treatment. In those who are treated there is a small increased risk of bleeding. Using GRADE assessment, the evidence was judged to be of moderate quality due to many trials having low numbers of participants. However, the results across studies were consistent and we have reasonable confidence in these results.

Compression stockings for preventing deep vein thrombosis in airline passengers.

BACKGROUND: Air travel might increase the risk of deep vein thrombosis (DVT). It has been suggested that wearing compression stockings might reduce this risk. This is an update of the review first published in 2006. OBJECTIVES: To assess the effects of wearing compression stockings versus not wearing them for preventing DVT in people travelling on flights lasting at least four hours. SEARCH METHODS: For this update the Cochrane Vascular Information Specialist (CIS) searched the Specialised Register (10 February 2016). In addition, the CIS searched the Cochrane Register of Studies (CENTRAL (2016, Issue 1)). SELECTION CRITERIA: Randomised trials of compression stockings versus no stockings in passengers on flights lasting at least four hours. Trials in which passengers wore a stocking on one leg but not the other, or those comparing stockings and another intervention were also eligible. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion and extracted data. We sought additional information from trialists where necessary. MAIN RESULTS: One new study that fulfilled the inclusion criteria was identified for this update. Eleven randomised trials (n = 2906) were included in this review: nine (n = 2821) compared wearing graduated compression stockings on both legs versus not wearing them; one trial (n = 50) compared wearing graduated compression tights versus not wearing them; and one trial (n = 35) compared wearing a graduated compression stocking on one leg for the outbound flight and on the other leg on the return flight. Eight trials included people judged to be at low or medium risk of developing DVT (n = 1598) and two included high-risk participants (n = 1273). All flights had a duration of more than five hours.Fifty of 2637 participants with follow-up data available in the trials of wearing compression stockings on both legs had a symptomless DVT; three wore stockings, 47 did not (odds ratio (OR) 0.10, 95% confidence interval (CI) 0.04 to 0.25, P < 0.001; high-quality evidence). There were no symptomless DVTs in three trials. Sixteen of 1804 people developed superficial vein thrombosis, four wore stockings, 12 did not (OR 0.45, 95% CI 0.18 to 1.13, P = 0.09; moderate-quality evidence). No deaths, pulmonary emboli or symptomatic DVTs were reported. Wearing stockings had a significant impact in reducing oedema (mean difference (MD) -4.72, 95% CI -4.91 to -4.52; based on six trials; low-quality evidence). A further two trials showed reduced oedema in the stockings group but could not be included in the meta-analysis as they used different methods to measure oedema. No significant adverse effects were reported. AUTHORS' CONCLUSIONS: There is high-quality evidence that airline passengers similar to those in this review can expect a substantial reduction in the incidence of symptomless DVT and low-quality evidence that leg oedema is reduced if they wear compression stockings. Quality was limited by the way that oedema was measured. There is moderate-quality evidence that superficial vein thrombosis may be reduced if passengers wear compression stockings. We cannot assess the effect of wearing stockings on death, pulmonary embolism or symptomatic DVT because no such events occurred in these trials. Randomised trials to assess these outcomes would need to include a very large number of people.

Thrombolysis for acute deep vein thrombosis.

BACKGROUND: Standard treatment for deep vein thrombosis aims to reduce immediate complications. Use of thrombolysis or clot dissolving drugs could reduce the long-term complications of post-thrombotic syndrome (PTS) (pain, swelling, skin discolouration, or venous ulceration) in the affected leg. This is the second update of a review first published in 2004. OBJECTIVES: To assess the effects of thrombolytic therapy and anticoagulation versus anticoagulation in the management of people with acute deep vein thrombosis (DVT) of the lower limb as determined by the effects on pulmonary embolism, recurrent venous thromboembolism, major bleeding, post-thrombotic complications, venous patency and venous function. SEARCH METHODS: For this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched April 2013) and CENTRAL (2013, Issue 4). SELECTION CRITERIA: Randomised controlled trials (RCTs) examining thrombolysis and anticoagulation versus anticoagulation for acute DVT were considered. DATA COLLECTION AND ANALYSIS: In the previous review of 2010, one review author (LW) selected trials, extracted data and assessed study quality, with checking at all stages by the other review author (MPA). If necessary, we sought additional information from trialists. For this update (2013), LW and CB selected trials, extracted data independently, and sought advice from MPA where necessary. All studies, existing and new, required full risk of bias assessment in line with current Cochrane procedures. Two of LW, CB and MA independently assessed risk of bias with discussion with the third author where necessary. MAIN RESULTS: Seventeen studies with 1103 participants were included. Complete clot lysis occurred significantly more often in the treatment group in early follow up (risk ratio (RR) 4.91; 95% confidence interval (CI) 1.66 to 14.53, P = 0.004) and at intermediate follow up (RR 2.37; 95% CI 1.48 to 3.80, P = 0.0004). A similar effect was seen for any degree of improvement in venous patency. Significantly less PTS occurred in those receiving thrombolysis, (RR 0.64; 95% CI 0.52 to 0.79, P < 0.0001). Leg ulceration was reduced although the data were limited by small numbers (RR 0.48; 95% CI 0.12 to 1.88, P = 0.29). Those receiving thrombolysis had significantly more bleeding complications (RR 2.23; 95% CI 1.41 to 3.52, P = 0.0006). Three strokes occurred in the treatment group, all in trials conducted pre-1990, and none in the control group. There was no significant effect on mortality detected at either early or intermediate follow up. Data on the occurrence of pulmonary embolism (PE) and recurrent DVT were inconclusive. Systemic thrombolysis is now not commonly used and catheter-directed thrombolysis (CDT) is the more favoured means of administration. This has been studied in iliofemoral DVT, and results from two trials are consistent with those from trials of systemic thrombolysis in DVT at other levels of occlusion. AUTHORS' CONCLUSIONS: Thrombolysis increases the patency of veins and reduces the incidence of PTS following proximal DVT by a third. Strict eligibility criteria are necessary to reduce the risk of bleeding complications and this limits the applicability of this treatment. In those who are treated there is a small increased risk of bleeding. In recent years CDT is the most studied route of administration, and results appear to be similar to systemic administration.

Subretinal delivery of adeno-associated virus serotype 2 results in minimal immune responses that allow repeat vector administration in immunocompetent mice.

BACKGROUND: Adeno-associated virus serotype 2 (AAV2) vectors show considerable promise for ocular gene transfer. However, one potential barrier to efficacious long-term therapy is the development of immune responses against the vector or transgene product. METHODS: We evaluated cellular and humoral responses in mice following both single and repeated subretinal administration of AAV2, and examined their effects on RPE65 and green fluorescent protein transgene expression. RESULTS: Following subretinal administration of vector, splenocytes and T-cells from draining lymph nodes showed minimal activation following stimulation by co-culture with AAV2. Neutralizing antibodies (NAbs) were not detected in the ocular fluids of any mice receiving AAV2 or in the serum of mice receiving a lower dose. NAbs were present in the serum of a proportion of mice receiving a higher dose of the vector. Furthermore, no differences in immunoglobulin titre in serum or ocular fluids against RPE65 protein or AAV2 capsid between treated and control mice were detected. Histological examination showed no evidence of retinal toxicity or leukocyte infiltration compared to uninjected eyes. Repeat administration of low-dose AAV.hRPE65.hRPE65 to both eyes of RPE65(-/-) mice resulted in transgene expression and functional rescue, but re-administration of high-dose AAV2 resulted in boosted NAb titres and variable transgene expression in the second injected eye. CONCLUSIONS: These data, which were obtained in mice, suggest that, following subretinal injection, immune responses to AAV2 are dose-dependent. Low-dose AAV2 is well tolerated in the eye, with minimal immune responses, and transgene expression after repeat administration of vector is achievable. Higher doses lead to the expression of NAbs that reduce the efficacy of repeated vector administration.

Local administration of an adeno-associated viral vector expressing IL-10 reduces monocyte infiltration and subsequent photoreceptor damage during experimental autoimmune uveitis.

Autoimmune posterior uveitis is a chronic, potentially blinding inflammatory disease of the eye. It is commonly treated with immunosuppressive drugs that have adverse long-term effects. Advances in gene transfer techniques have enabled long-term, stable transduction of retinal cells following subretinal injection with adeno-associated viral (AAV) vectors. Here we report for the first time that subretinal injection of rAAV-2 encoding murine IL-10 into the retina of C57BL/6 mice significantly decreases the median experimental autoimmune uveitis (EAU) disease severity. This protection is shown to be due to a decrease in the number and activation status of infiltrating monocytes during EAU, as determined by costimulatory molecule expression and nitrotyrosine detection. No differences within splenocyte proliferative responses or serum antibody levels were detected, emphasizing the potential of gene therapy strategies in ameliorating autoimmune responses in local microenvironments without unwanted systemic effects.

Minocycline delays photoreceptor death in the rds mouse through a microglia-independent mechanism.

PURPOSE: Minocycline, a semi-synthetic tetracycline antibiotic is reported to be neuroprotective in degenerative and ischaemic models of central nervous system disease, via mechanisms involving suppression of both cytotoxic microglial activity and caspase-dependent apoptosis. We have investigated the effect of minocycline treatment on a mouse model of retinitis pigmentosa, an inherited photoreceptor neurodegenerative disorder, and contrasted this with the effect of depleting retinal microglia using liposomal clodronate. METHODS: rds mice were treated intraperitoneally from the second postnatal day (P2) with either daily minocycline until P16, P18, P21, P24 and P27 or alternative day clodronate liposomes until P16. Immunohistochemical and immunofluorescent methods were applied for the detection of microglia (F4/80) and apoptosis (TUNEL and caspase 3 activation). RESULTS: Photoreceptor apoptosis was delayed by minocycline treatment but not, ultimately, prevented. Markedly reduced expression of activated caspase 3 was observed in photoreceptors at the early time point, corresponding with the reduced level of apoptosis. Delayed photoreceptor apoptosis due to minocycline treatment was associated with a 50% reduction in the numbers of microglia at early timepoints. Liposomal clodronate treatment also resulted in a marked reduction in the number of microglia (63% reduction in microglia), but in contrast to minocycline treatment, this had no effect on photoreceptor apoptosis. CONCLUSIONS: Minocycline appears to delay photoreceptor apoptosis through a microglia-independent action. Although microglial cytotoxicity has been implicated during other models of neurodegeneration, microglia are unlikely to play such a role in this model of photoreceptor dystrophy.

Control of myeloid activity during retinal inflammation.

Combating myeloid cell-mediated destruction of the retina during inflammation or neurodegeneration is dependent on the integrity of homeostatic mechanisms within the tissue that may suppress T cell activation and their subsequent cytokine responses, modulate infiltrating macrophage activation, and facilitate healthy tissue repair. Success is dependent on response of the resident myeloid-cell populations [microglia (MG)] to activation signals, commonly cytokines, and the control of infiltrating macrophage activation during inflammation, both of which appear highly programmed in normal and inflamed retina. The evidence that tissue CD200 constitutively provides down-regulatory signals to myeloid-derived cells via cognate CD200-CD200 receptor (R) interaction supports inherent tissue control of myeloid cell activation. In the retina, there is extensive neuronal and endothelial expression of CD200. Retinal MG in CD200 knockout mice display normal morphology but unlike the wild-type mice, are present in increased numbers and express nitric oxide synthase 2, a macrophage activation marker, inferring that loss of CD200 or absent CD200R ligation results in "classical" activation of myeloid cells. Thus, when mice lack CD200, they show increased susceptibility to and accelerated onset of tissue-specific autoimmunity.