Educational and behavioural interventions for anticoagulant therapy in patients with atrial fibrillation

BACKGROUND

Current guidelines recommend oral anticoagulation therapy for patients with atrial fibrillation (AF) with one or more risk factors for stroke; however, anticoagulation control (time in therapeutic range (TTR)) with vitamin K antagonists (VKAs) is dependent on many factors. Educational and behavioural interventions may impact patients' ability to maintain their international normalised ratio (INR) control. This is an updated version of the original review first published in 2013.

OBJECTIVES

To evaluate the effects of educational and behavioural interventions for oral anticoagulation therapy (OAT) on TTR in patients with AF.

SEARCH METHODS

We updated searches from the previous review by searching the Cochrane Central Register of Controlled Trials (CENTRAL) and the Database of Abstracts of Reviews of Effects (DARE) in The Cochrane Library (January 2016, Issue 1), MEDLINE Ovid (1949 to February week 1 2016), EMBASE Classic + EMBASE Ovid (1980 to Week 7 2016), PsycINFO Ovid (1806 to Week 1 February 2016) and CINAHL Plus with Full Text EBSCO (1937 to 16/02/2016). We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials evaluating the effect of any educational and behavioural intervention compared with usual care, no intervention, or intervention in combination with other self-management techniques among adults with AF who were eligible for, or currently receiving, OAT.

DATA COLLECTION AND ANALYSIS

Two of the review authors independently selected studies and extracted data. Risk of bias was assessed using the Cochrane 'Risk of bias' tool. We included outcome data on TTR, decision conflict (patient's uncertainty in making health-related decisions), percentage of INRs in the therapeutic range, major bleeding, stroke and thromboembolic events, patient knowledge, patient satisfaction, quality of life (QoL), beliefs about medication, illness perceptions, and anxiety and depression. We pooled data for three outcomes - TTR, anxiety and depression, and decision conflict - and reported mean differences (MD). Where insufficient data were present to conduct a meta-analysis, we reported effect sizes and confidence intervals (CI) from the included studies. We evaluated the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework.

MAIN RESULTS

Eleven trials with a total of 2246 AF patients (ranging from 14 to 712 by study) were included within the review. Studies included education, decision aids, and self-monitoring plus education interventions. The effect of self-monitoring plus education on TTR was uncertain compared with usual care (MD 6.31, 95% CI -5.63 to 18.25, I2 = 0%, 2 trials, 69 participants, very low-quality evidence). We found small but positive effects of education on anxiety (MD -0.62, 95% CI -1.21 to -0.04, I2 = 0%, 2 trials, 587 participants, low-quality evidence) and depression (MD -0.74, 95% CI -1.34 to -0.14, I2 = 0%, 2 trials, 587 participants, low-quality evidence) compared with usual care. The effect of decision aids on decision conflict favoured usual care (MD -0.1, 95% CI -0.17 to -0.02, I2 = 0%, 2 trials, 721 participants, low-quality evidence).

AUTHORS' CONCLUSIONS

This review demonstrates that there is insufficient evidence to draw definitive conclusions regarding the impact of educational or behavioural interventions on TTR in AF patients receiving OAT. Thus, more trials are needed to examine the impact of interventions on anticoagulation control in AF patients and the mechanisms by which they are successful. It is also important to explore the psychological implications for patients suffering from this long-term chronic condition.

Prophylactic antibiotics for preventing Gram positive infections associated with long-term central venous catheters in oncology patients

BACKGROUND

This is an updated version of the review which was first published in the Cochrane Database of Systematic Reviews in 2006. Long-term central venous catheters (CVCs), including tunnelled CVCs (TCVCs) and totally implanted devices or ports (TIDs), are increasingly used when treating oncology patients. Despite international guidelines on sterile insertion and appropriate CVC maintenance and use, infection remains a common complication. These infections are mainly caused by Gram positive bacteria. Antimicrobial prevention strategies aimed at these micro-organisms could potentially decrease the majority of CVC infections. The aim of this review was to evaluate the efficacy of antibiotics in the prevention of Gram positive infections in long-term CVCs.

OBJECTIVES

To determine the efficacy of administering antibiotics prior to the insertion of long-term CVCs, or flushing or locking long-term CVCs with a combined antibiotic and heparin solution, or both, to prevent Gram positive catheter-related infections in adults and children receiving treatment for cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (to June 2013) and the MEDLINE and EMBASE databases (1966 to 2013).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing prophylactic antibiotics given prior to long-term CVC insertion with no antibiotics, RCTs comparing a combined antibiotic and heparin solution with a heparin-only solution to flush or lock newly inserted long-term CVCs, and RCTs comparing a combination of these interventions in adults and children receiving treatment for cancer.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies, classified them and extracted data on to a pre-designed data collection form. We pooled data using the RevMan software version 5.2 and used random-effects (RE) model methods for meta-analyses.

MAIN RESULTS

We included 11 trials with a total of 828 oncology patients (adults and children). We assessed most included studies to be at a low or unclear risk of bias. Five trials compared the use of antibiotics (vancomycin, teicoplanin or ceftazidime) given before the insertion of the long-term CVC with no antibiotics, and six trials compared antibiotics (vancomycin, amikacin or taurolidine) and heparin with a heparin-only solution for flushing or locking the long-term CVC after use. Administering an antibiotic prior to insertion of the CVC did not significantly reduce Gram positive catheter-related sepsis (CRS) (five trials, 360 adults; risk ratio (RR) 0.72, 95% confidence interval (CI) 0.33 to 1.58; I² = 5 2%; P = 0.41).Flushing and locking long-term CVCs with a combined antibiotic and heparin solution significantly reduced the risk of Gram positive catheter-related sepsis compared with a heparin-only solution (468 participants, mostly children; RR 0.47, 95% CI 0.28 to 0.80; I² = 0%; P = 0.005). For a baseline infection rate of 15%, this reduction translated into a number needed to treat (NNT) of 12 (95% CI 9 to 33) to prevent one catheter-related infection. We considered this evidence to be of a moderate quality.

AUTHORS' CONCLUSIONS

There was no benefit to administering antibiotics before the insertion of long-term CVCs to prevent Gram positive catheter-related infections. Flushing or locking long-term CVCs with a combined antibiotic and heparin solution appeared to reduce Gram positive catheter-related sepsis experienced in people at risk of neutropenia through chemotherapy or disease. Due to insufficient data it was not clear whether this applied equally to TCVCs and totally implanted devices (TIDs), or equally to adults and children. The use of a combined antibiotic and heparin solution may increase microbial antibiotic resistance, therefore it should be reserved for high risk people or where baseline CVC infection rates are high (> 15%). Further research is needed to identify high risk groups most likely to benefit.

Dosing of unfractionated heparin in obese patients with venous thromboembolism

BACKGROUND

Aggressive weight-based dosing guidelines help achieve prompt therapeutic anticoagulation in patients with venous thromboembolism (VTE). While obese patients with VTE face an increased risk of recurrence, physicians typically resist prescribing doses two to three times the usual dose because of concern about bleeding complications.

OBJECTIVE

To examine the use of unfractionated heparin in obese patients with VTE at an academic teaching hospital in order to document the extent and pattern of underprescribing in this high-risk patient population.

DESIGN

Three-year, cross-sectional consecutive case series.

PATIENTS

Adult inpatients with VTE and a body mass index ≥30 kg/m(2) who were treated with unfractionated heparin.

MEASUREMENTS

Time to achievement of therapeutic anticoagulation (activated partial thromboplastin time >60 s) and gap between recommended and prescribed heparin doses.

RESULTS

Time to attainment of therapeutic anticoagulation exceeded 24 h in 29% of study patients (n = 84) and exceeded 48 h in 14% of patients. In 75 patients (89%), the prescribed bolus dose fell below the recommended dose of 80 units/kg, and in 64 patients (76%) the initial continuous infusion fell more than 100 units/h below--in some cases more than 1000 units/h below--the recommended dose of 18 units/kg/h. There was a significant correlation between time to therapeutic anticoagulation and initial infusion dose (Spearman r = -0.27; p < 0.02). Each decrease of 1 unit/kg/h translated to a delay ranging from about 0.75 h to 1.5 h over the range of prescribed doses (6 to 22 units/kg/h).

CONCLUSIONS

A substantial proportion of obese patients treated with unfractionated heparin experienced a delay >24 h in achieving adequate anticoagulation, and the vast majority received an inadequate heparin bolus or initial continuous infusion (or both) according to current dosing guidelines.

Prolonged thromboprophylaxis with low molecular weight heparin for abdominal or pelvic surgery

BACKGROUND

This an update of the review first published in 2009.Major abdominal and pelvic surgery carries a high risk of venous thromboembolism (VTE). The efficacy of thromboprophylaxis with low molecular weight heparin (LMWH) administered during the in-hospital period is well-documented, but the optimal duration of prophylaxis after surgery remains controversial. Some studies suggest that patients undergoing major abdominopelvic surgery benefit from prolongation of the prophylaxis up to 28 days after surgery.

OBJECTIVES

To evaluate the efficacy and safety of prolonged thromboprophylaxis with LMWH for at least 14 days after abdominal or pelvic surgery compared with thromboprophylaxis administered during the in-hospital period only in preventing late onset VTE.

SEARCH METHODS

We performed electronic searches on 28 October 2017 in the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, LILACS and registered trials (Clinicaltrials.gov October 28, 2017 and World Health Organization International Clinical Trials Registry Platform (ICTRP) 28 October 2017). Abstract books from major congresses addressing thromboembolism were handsearched from 1976 to 28 October 2017, as were reference lists from relevant studies.

SELECTION CRITERIA

We assessed randomized controlled clinical trials (RCTs) comparing prolonged thromboprophylaxis (≥ fourteen days) with any LMWH agent with placebo, or other methods, or both to thromboprophylaxis during the admission period only. The population consisted of persons undergoing abdominal or pelvic surgery for both benign and malignant pathology. The outcome measures included VTE (deep venous thrombosis (DVT) or pulmonary embolism (PE)) as assessed by objective means (venography, ultrasonography, pulmonary ventilation/perfusion scintigraphy, spiral computed tomography (CT) scan or autopsy). We excluded studies exclusively reporting on clinical diagnosis of VTE without objective confirmation.

DATA COLLECTION AND ANALYSIS

Review authors identified studies and extracted data. Outcomes were VTE (DVT or PE) assessed by objective means. Safety outcomes were defined as bleeding complications and mortality within three months after surgery. Sensitivity analyses were also performed with unpublished studies excluded, and with study participants limited to those undergoing solely open and not laparoscopic surgery. We used a fixed-effect model for analysis.

MAIN RESULTS

We identified seven RCTs (1728 participants) evaluating prolonged thromboprophylaxis with LMWH compared with control or placebo. The searches resulted in 1632 studies, of which we excluded 1528. One hundred and four abstracts, eligible for inclusion, were assessed of which seven studies met the inclusion criteria.For the primary outcome, the incidence of overall VTE after major abdominal or pelvic surgery was 13.2% in the control group compared to 5.3% in the patients receiving out-of-hospital LMWH (Mantel Haentzel (M-H) odds ratio (OR) 0.38, 95% confidence interval (CI) 0.26 to 0.54; I2 = 28%; moderate-quality evidence).For the secondary outcome of all DVT, seven studies, n = 1728, showed prolonged thromboprophylaxis with LMWH to be associated with a statistically significant reduction in the incidence of all DVT (M-H OR 0.39, 95% CI 0.27 to 0.55; I2 = 28%; moderate-quality evidence).We found a similar reduction when analysis was limited to incidence in proximal DVT (M-H OR 0.22, 95% CI 0.10 to 0.47; I2 = 0%; moderate-quality evidence).The incidence of symptomatic VTE was also reduced from 1.0% in the control group to 0.1% in patients receiving prolonged thromboprophylaxis (M-H OR 0.30, 95% CI 0.08 to 1.11; I2 = 0%; moderate-quality evidence).No difference in the incidence of bleeding between the control and LMWH group was found, 2.8% and 3.4%, respectively (M-H OR 1.10, 95% CI 0.67 to 1.81; I2 = 0%; moderate-quality evidence).No difference in mortality between the control and LMWH group was found, 3.8% and 3.9%, respectively (M-H OR 1.15, 95% CI 0.72 to 1.84; moderate-quality evidence).Estimates of heterogeneity ranged between 0% and 28% depending on the analysis, suggesting low or unimportant heterogeneity.

AUTHORS' CONCLUSIONS

Prolonged thromboprophylaxis with LMWH significantly reduces the risk of VTE compared to thromboprophylaxis during hospital admittance only, without increasing bleeding complications or mortality after major abdominal or pelvic surgery. This finding also holds true for DVT alone, and for both proximal and symptomatic DVT. The quality of the evidence is moderate and provides moderate support for routine use of prolonged thromboprophylaxis. Given the low heterogeneity between studies and the consistent and moderate evidence of a decrease in risk for VTE, our findings suggest that additional studies may help refine the degree of risk reduction but would be unlikely to significantly influence these findings. This updated review provides additional evidence and supports the previous results reported in the 2009 review.

Antiplatelet drugs for polycythaemia vera and essential thrombocythaemia

BACKGROUND

Polycythaemia vera and essential thrombocythaemia are chronic Philadelphia-negative myeloproliferative neoplasms that increase the risk of arterial and venous thrombosis, as well as bleeding. In addition to the different therapeutic strategies available, an antiplatelet drug is often used to reduce thrombotic risk.

OBJECTIVES

To quantify the benefit and harm of antiplatelet drugs for long-term primary and secondary prophylaxis of arterial and venous thrombotic events in patients with polycythaemia vera or essential thrombocythaemia.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), The Cochrane Library (Issue 1 2012), MEDLINE (1966 to 2012), and EMBASE (1980 to 2012), as well as online registers of ongoing trials and conference proceedings. The date of the last search was October 2012.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing long-term (>6 months) use of an antiplatelet drug versus placebo or no treatment in participants with polycythaemia vera or essential thrombocythaemia, as diagnosed by established international criteria, with data for at least one of the selected outcomes.

DATA COLLECTION AND ANALYSIS

Using a pre-defined extraction form, two review authors independently screened results, extracted data, and assessed quality. We planned to analyse the following outcomes: mortality from arterial and venous thrombotic events (primary efficacy outcome), mortality from bleeding episodes (primary safety outcome), fatal and non-fatal arterial thrombotic events, fatal and non-fatal venous thrombotic events, micro-circulation events, transient neurological and ocular manifestations, major and minor bleeding episodes, and all-cause mortality and any adverse events. We based quantitative analysis of outcome data on an intention-to-treat principle. We used the pooled odds ratio (OR) with 95% confidence interval (CI) with a fixed-effect model (Mantel-Haenszel) to estimate the overall treatment effect.

MAIN RESULTS

We identified no new studies from the updated searches. We included in this review two RCTs for a total of 630 participants. Both RCTs included participants with an established diagnosis of polycythaemia vera and with no clear indication or contraindication to aspirin therapy. We judged both studies to be of moderate quality. Published data from both studies were insufficient for a time-to-event data analysis and for some of the primary and secondary outcomes that we planned. The use of low-dose aspirin, compared with placebo, was associated with a lower risk of fatal thrombotic events (although this benefit was not statistically significant (OR 0.20, 95% CI 0.03 to 1.14; P = 0.07). No data on mortality from bleeding episodes were available. A non-significant benefit of aspirin was shown for all-cause mortality (OR 0.46, 95% CI 0.21 to 1.01; P = 0.05). No increase in the risk of major bleeding was reported in participants taking aspirin compared with those given placebo (OR 0.99, 95% CI 0.23 to 4.36; P = 0.99), and a non-significant increase with aspirin treatment was shown for minor bleeding (OR 1.85, 95% CI 0.90 to 3.79; P = 0.09). No published studies have reported findings in participants with essential thrombocythaemia or in the study of other antiplatelet drugs.

AUTHORS' CONCLUSIONS

For patients with polycythaemia vera who have no clear indication or contraindication to aspirin therapy, available evidence suggests that the use of low-dose aspirin, when compared with no treatment, is associated with a statistically non-significant reduction in the risk of fatal thrombotic events and all-cause mortality, without an increased risk of major bleeding.

Antifibrinolytic therapy for preventing oral bleeding in people on anticoagulants undergoing minor oral surgery or dental extractions

BACKGROUND

Individuals on continuous treatment with vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs) are at increased risk of bleeding complications during and after oral or dental procedures. Anticoagulant treatment is preferably continued at the same dose, since dose reduction or discontinuation of treatment is associated with an increased risk of thromboembolism. The use of haemostatic measures during or after the procedure (or both) could enable continuation of the oral anticoagulant treatment.

OBJECTIVES

We aimed to assess the efficacy of antifibrinolytic agents for preventing bleeding complications in people on oral anticoagulants undergoing minor oral surgery or dental extractions.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Coagulopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews. We searched PubMed, Embase and the Cochrane Library. Additional searches were performed using ClinicalTrials.gov, the International Clinical Trials Registry Platform (ICTRP), the CINAHL database of nursing and allied health services, the open access ProQuest dissertation database, papers and reports from the American College of Clinical Pharmacy (ACCP) and abstract books from annual scientific conferences.Date of last search: 04 January 2018.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials in people on continuous treatment with VKAs or DOACs undergoing oral or dental procedures using antifibrinolytic agents (tranexamic acid (TXA) or epsilon aminocaproic acid) to prevent perioperative bleeding compared to no intervention or usual care with or without placebo.

DATA COLLECTION AND ANALYSIS

Two authors independently screened the titles and abstracts of all identified articles. Full texts were obtained from potentially relevant abstracts and two authors independently assessed these for inclusion based of the selection criteria. A third author verified trial eligibility. Two authors independently performed data extraction and risk of bias assessments using standardized forms. The quality of the evidence was assessed using GRADE.

MAIN RESULTS

No eligible trials in people on continuous treatment with DOACs undergoing oral or dental procedures were identified.Three randomised trials and one quasi-randomised trial (follow-up in all was seven days) in people on continuous treatment with VKAs were included with a total of 253 participants (mean age 60 years). Two trials published in 1989 and 1993 compared the antifibrinolytic agent TXA with placebo in people using VKAs. Two other trials were published in 1999 and 2015 and compared TXA with gelatin sponge and sutures, and dry gauze compression, respectively. In all included trials, those who were treated with VKAs had international normalised ratio (INR) values within the therapeutic range and TXA was applied locally, not systemically.The two trials from 1989 and 1993 comparing TXA with placebo showed a statistically significant beneficial effect regarding the number of major postoperative bleeding episodes requiring intervention, with a pooled risk difference (RD) of -0.25 (95% confidence interval (CI) -0.36 to -0.14) (128 participants) (moderate-quality evidence). For the two trials that compared TXA with either gelatin sponge and sutures or with dry gauze compression, there was no difference between the TXA and the standard care group, RD 0.02 (95% CI -0.07 to 0.11) (125 participants) (moderate-quality evidence). The combined RD of all included trials was -0.13 (95% CI -0.30 to 0.05) (moderate-quality evidence). There were no side effects of antifibrinolytic therapy that required treatment withdrawal (128 participants) (moderate-quality evidence). Despite heterogeneity between trials with respect to the different haemostatic measures used in the control groups, the trials were comparable regarding design and baseline participant characteristics.Overall, we considered the risk of bias to be low in the trials comparing TXA with placebo and moderate in the trials comparing TXA with alternative haemostatic measures.

AUTHORS' CONCLUSIONS

Based on the results of this Cochrane Review, there seems to be a beneficial effect of locally applied TXA in preventing oral bleeding in people on continuous treatment with VKAs undergoing minor oral surgery or dental extractions. However, the small number of identified randomised controlled trials, the relatively small number of participants included in the trials and the differences in standard therapy and treatment regimens between trials, do not allow us to conclude definite efficacy of antifibrinolytic therapy in this population.We were unable to identify any eligible trials in people on continuous treatment with DOACs undergoing oral or dental procedures. Therefore, a beneficial effect of antifibrinolytic therapy can currently only be assumed based on data from the people using VKAs.

Once versus twice daily low molecular weight heparin for the initial treatment of venous thromboembolism

BACKGROUND

In the initial treatment of venous thromboembolism (VTE) low molecular weight heparin (LMWH) is administered once or twice daily. A once daily treatment regimen is more convenient for the patient and may optimise home treatment. However, it is not clear whether a once daily treatment regimen is as safe and effective as a twice daily treatment regimen. This is the second update of a review first published in 2003.

OBJECTIVES

To compare the efficacy and safety of once daily versus twice daily administration of LMWH.

SEARCH METHODS

For this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched May 2013) and CENTRAL (2013, Issue 4).

SELECTION CRITERIA

Randomised clinical trials in which LMWH given once daily is compared with LMWH given twice daily for the initial treatment of VTE.

DATA COLLECTION AND ANALYSIS

Two review authors assessed trials for inclusion and extracted data independently.

MAIN RESULTS

Five studies were included with a total of 1508 participants. The pooled data showed no statistically significant difference in recurrent VTE between the two treatment regimens (OR 0.82, 0.49 to 1.39; P = 0.47). A comparison of major haemorrhagic events (OR 0.77, 0.40 to 1.45; P = 0.41), improvement of thrombus size (OR 1.41, 0.66 to 3.01; P = 0.38) and mortality (OR 1.14, 0.62 to 2.08; P = 0.68) also showed no statistically significant differences between the two treatment regimens. None of the five included studies reported data on post-thrombotic syndrome.

AUTHORS' CONCLUSIONS

Once daily treatment with LMWH is as effective and safe as twice daily treatment with LMWH.

Prolonged thromboprophylaxis with low molecular weight heparin for abdominal or pelvic surgery

BACKGROUND

This an update of the review first published in 2009.Major abdominal and pelvic surgery carries a high risk of venous thromboembolism (VTE). The efficacy of thromboprophylaxis with low molecular weight heparin (LMWH) administered during the in-hospital period is well-documented, but the optimal duration of prophylaxis after surgery remains controversial. Some studies suggest that patients undergoing major abdominopelvic surgery benefit from prolongation of the prophylaxis up to 28 days after surgery.

OBJECTIVES

To evaluate the efficacy and safety of prolonged thromboprophylaxis with LMWH for at least 14 days after abdominal or pelvic surgery compared with thromboprophylaxis administered during the in-hospital period only in preventing late onset VTE.

SEARCH METHODS

We performed electronic searches on 28 October 2017 in the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, LILACS and registered trials (Clinicaltrials.gov October 28, 2017 and World Health Organization International Clinical Trials Registry Platform (ICTRP) 28 October 2017). Abstract books from major congresses addressing thromboembolism were handsearched from 1976 to 28 October 2017, as were reference lists from relevant studies.

SELECTION CRITERIA

We assessed randomized controlled clinical trials (RCTs) comparing prolonged thromboprophylaxis (≥ fourteen days) with any LMWH agent with placebo, or other methods, or both to thromboprophylaxis during the admission period only. The population consisted of persons undergoing abdominal or pelvic surgery for both benign and malignant pathology. The outcome measures included VTE (deep venous thrombosis (DVT) or pulmonary embolism (PE)) as assessed by objective means (venography, ultrasonography, pulmonary ventilation/perfusion scintigraphy, spiral computed tomography (CT) scan or autopsy). We excluded studies exclusively reporting on clinical diagnosis of VTE without objective confirmation.

DATA COLLECTION AND ANALYSIS

Review authors identified studies and extracted data. Outcomes were VTE (DVT or PE) assessed by objective means. Safety outcomes were defined as bleeding complications within three months after surgery. Sensitivity analyses were also performed with unpublished studies excluded, and with study participants limited to those undergoing solely open and not laparoscopic surgery. We used a fixed-effect model for analysis.

MAIN RESULTS

We identified seven RCTs (1728 participants) evaluating prolonged thromboprophylaxis with LMWH compared with control or placebo. The searches resulted in 1632 studies, of which we excluded 1528. One hundred and four abstracts, eligible for inclusion, were assessed of which seven studies met the inclusion criteria.For the primary outcome, the incidence of overall VTE after major abdominal or pelvic surgery was 13.2% in the control group compared to 5.3% in the patients receiving out-of-hospital LMWH (Mantel Haentzel (M-H) odds ratio (OR) 0.38, 95% confidence interval (CI) 0.26 to 0.54; I2 = 28%; seven studies, n = 1728; moderate-quality evidence).For the secondary outcome of all DVT, seven studies, n = 1728, showed prolonged thromboprophylaxis with LMWH to be associated with a statistically significant reduction in the incidence of all DVT (M-H OR 0.39, 95% CI 0.27 to 0.55; I2 = 28%; moderate-quality evidence).We found a similar reduction when analysis was limited to incidence in proximal DVT (M-H OR 0.22, 95% CI 0.10 to 0.47; I2 = 0%; moderate-quality evidence).The incidence of symptomatic VTE was also reduced from 1.0% in the control group to 0.1% in patients receiving prolonged thromboprophylaxis (M-H OR 0.30, 95% CI 0.08 to 1.11; I2 = 0%; moderate-quality evidence).No difference in the incidence of bleeding between the control and LMWH group was found, 2.8% and 3.4%, respectively (HM-H OR 1.10, 95% CI 0.67 to 1.81; I2 = 0%; seven studies, n = 2239; moderate-quality evidence).Estimates of heterogeneity ranged between 0% and 28% depending on the analysis, suggesting low or unimportant heterogeneity.

AUTHORS' CONCLUSIONS

Prolonged thromboprophylaxis with LMWH significantly reduces the risk of VTE compared to thromboprophylaxis during hospital admittance only, without increasing bleeding complications after major abdominal or pelvic surgery. This finding also holds true for DVT alone, and for both proximal and symptomatic DVT. The quality of the evidence is moderate and provides moderate support for routine use of prolonged thromboprophylaxis. Given the low heterogeneity between studies and the consistent and moderate evidence of a decrease in risk for VTE, our findings suggest that additional studies may help refine the degree of risk reduction but would be unlikely to significantly influence these findings. This updated review provides additional evidence and supports the previous results reported in the 2009 review.

Treatment for superficial infusion thrombophlebitis of the upper extremity

BACKGROUND

Although superficial thrombophlebitis of the upper extremity represents a frequent complication of intravenous catheters inserted into the peripheral veins of the forearm or hand, no consensus exists on the optimal management of this condition in clinical practice.

OBJECTIVES

To summarise the evidence from randomised clinical trials (RCTs) concerning the efficacy and safety of (topical, oral or parenteral) medical therapy of superficial thrombophlebitis of the upper extremity.

SEARCH METHODS

The Cochrane Vascular Group Trials Search Co-ordinator searched the Specialised Register (last searched April 2015) and the Cochrane Register of Studies (2015, Issue 3). Clinical trials registries were searched up to April 2015.

SELECTION CRITERIA

RCTs comparing any (topical, oral or parenteral) medical treatment to no intervention or placebo, or comparing two different medical interventions (e.g. a different variant scheme or regimen of the same intervention or a different pharmacological type of treatment).

DATA COLLECTION AND ANALYSIS

We extracted data on methodological quality, patient characteristics, interventions and outcomes, including improvement of signs and symptoms as the primary effectiveness outcome, and number of participants experiencing side effects of the study treatments as the primary safety outcome.

MAIN RESULTS

We identified 13 studies (917 participants). The evaluated treatment modalities consisted of a topical treatment (11 studies), an oral treatment (2 studies) and a parenteral treatment (2 studies). Seven studies used a placebo or no intervention control group, whereas all others also or solely compared active treatment groups. No study evaluated the effects of ice or the application of cold or hot bandages. Overall, the risk of bias in individual trials was moderate to high, although poor reporting hampered a full appreciation of the risk in most studies. The overall quality of the evidence for each of the outcomes varied from low to moderate mainly due to risk of bias and imprecision, with only single trials contributing to most comparisons. Data on primary outcomes improvement of signs and symptoms and side effects attributed to the study treatment could not be statistically pooled because of the between-study differences in comparisons, outcomes and type of instruments to measure outcomes.An array of topical treatments, such as heparinoid or diclofenac gels, improved pain compared to placebo or no intervention. Compared to placebo, oral non-steroidal anti-inflammatory drugs reduced signs and symptoms intensity. Safety issues were reported sparsely and were not available for some interventions, such as notoginseny creams, parenteral low-molecular-weight heparin or defibrotide. Although several trials reported on adverse events with topical heparinoid creams, Essaven gel or phlebolan versus control, the trials were underpowered to adequately measure any differences between treatment modalities. Where reported, adverse events with topical treatments consisted mainly of local allergic reactions. Only one study of 15 participants assessed thrombus extension and symptomatic venous thromboembolism with either oral non-steroidal anti-inflammatory drugs or low-molecular-weight heparin, and it reported no cases of either. No study reported on the development of suppurative phlebitis, catheter-related bloodstream infections or quality of life.

AUTHORS' CONCLUSIONS

The evidence about the treatment of acute infusion superficial thrombophlebitis is limited and of low quality. Data appear too preliminary to assess the effectiveness and safety of topical treatments, systemic anticoagulation or oral non-steroidal anti-inflammatory drugs.

Slow versus fast subcutaneous heparin injections for prevention of bruising and site pain intensity

BACKGROUND

Heparin is an anticoagulant medication that is usually injected subcutaneously. Subcutaneous administration of heparin may result in complications such as bruising, haematoma, and pain at the injection site. One of the factors that may affect pain, haematoma, and bruising is injection speed. For patients and healthcare providers, strategies that can reduce pain and bruising are considered important. Reducing patients' discomfort and concerns whenever and wherever possible is an important aim of nursing. Several studies have been carried out to see if speed of injection affects the amount of pain and bruising where the injection is given, but results of these studies have differed and study authors have not reached a clear final conclusion. This is the first update of the review first published in 2014.

OBJECTIVES

To assess the effects of duration (speed) of subcutaneous heparin injection on pain, haematoma, and bruising at the injection site in people admitted to hospitals or clinics who require treatment with unfractionated heparin (UFH) or low molecular weight heparin (LMWH).

SEARCH METHODS

For this update, the Cochrane Vascular Information Specialist (CIS) searched the Specialised Register (last searched March 2017) and the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2). The CIS also searched trials registries for details of ongoing or unpublished studies. Review authors searched two Persian databases - Iranmedex and Scientific Information Database (SID) - as well as Google Scholar.

SELECTION CRITERIA

We sought randomised controlled trials (RCTs) comparing the effects of different durations of subcutaneous injection of heparin on pain, bruising, and haematoma at the injection site.

DATA COLLECTION AND ANALYSIS

Two review authors (MM, LJ), working independently, extracted data onto a structured form and assessed study quality. We used the criteria recommended by Cochrane to assess the risk of bias of included studies. For the outcomes, we calculated the mean difference (MD) or the standardised MD (SMD) with corresponding 95% confidence intervals (CIs). We pooled data using fixed-effect and random-effects models. We used GRADE to assess the overall quality of evidence supporting outcomes assessed in this review.

MAIN RESULTS

For this update, we identified three new studies and therefore included in the Review four studies with a total of 459 participants who received subcutaneous injections of LMWH into the abdomen. Only one trial reported the injected drug volume (0.4 mL). Owing to the nature of the intervention, it was not possible to blind participants and care givers (personnel) in any included study. Two studies described blinding of outcome assessors; therefore overall, the methodological quality of included studies was moderate. The duration of the fast injection was 10 seconds and the duration of the slow injection was 30 seconds in all included studies.Three studies reported site pain intensity after each injection at different time points. Two studies assessed site pain intensity immediately after each injection, and meta-analysis on 140 participants showed no clear difference in site pain intensity immediately post slow injection when compared to fast injection (low-quality evidence; P = 0.15). In contrast, meta-analysis of two studies with 59 participants showed that 48 hours after the heparin injection, slow injection was associated with less pain intensity compared to fast injection (low-quality evidence; P = 0.007). One study (40 participants) reported pain intensity at 60 and 72 hours after injection. This study described no clear difference in site pain intensity at 60 and 72 hours post slow injection compared to fast injection.All four included studies assessed bruise size at 48 hours after each injection. Meta-analysis on 459 participants showed no difference in bruise size after slow injection compared to fast injection (low-quality evidence; P = 0.07). None of the included studies measured the incidence of haematoma as an outcome.

AUTHORS' CONCLUSIONS

We found four RCTs that evaluated the effect of subcutaneous heparin injection duration on pain intensity and bruise size. Owing to the small numbers of participants, we found insufficient evidence to determine any effect on pain intensity immediately after injection or at 60 and 72 hours post injection. However, slow injection may reduce site pain intensity 48 hours after injection (low-quality evidence). We observed no clear difference in bruise size after slow injection compared to fast injection (low-quality evidence). We judged this evidence to be of low quality owing to imprecision and inconsistency.

Vitamin K for improved anticoagulation control in patients receiving warfarin

BACKGROUND

Effective use of warfarin involves keeping the international normalised ratio (INR) within a relatively narrow therapeutic range. However, patients respond widely to their dose of warfarin. Overcoagulation can lead to an increased risk of excessive bleeding, while undercoagulation can lead to increased clot formation. There is some evidence that patients with a variable response to warfarin may benefit from a concomitant low dose of vitamin K.

OBJECTIVES

To assess the effects of concomitant supplementation of low-dose oral vitamin K for anticoagulation control in patients being initiated on or taking a maintenance dose of warfarin.

SEARCH METHODS

To identify previous reviews, we searched the Database of Abstracts of Reviews of Effects (DARE via The Cochrane Library, Wiley) (Issue 2, 2011). To identify primary studies, we searched the Cochrane Central Register of Controlled Trials (CENTRAL via The Cochrane Library, Wiley) (Issue 2, 2014), Ovid MEDLINE (R) In-Process & Other Non-Indexed Citations database and Ovid MEDLINE (R) (OvidSP) (1946 to 25 February 2014), Embase (OvidSP) (1974 to week 8 of 2014), Science Citation Index Expanded™ & Conference Proceedings Citation Index - Science (Web of Science™) (1945 to 27 February 2014), and the NHS Economics Evaluations Database (NHS EED) (via The Cochrane Library, Wiley) (Issue 2, 2014). We did not apply any language or date restrictions. We used additional methods to identify grey literature and ongoing studies.

SELECTION CRITERIA

Randomised controlled trials comparing the addition of vitamin K versus placebo in patients initiating warfarin or already taking warfarin.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected and extracted data from included studies. When disagreement arose, a third author helped reached a consensus. We also assessed risk of bias.

MAIN RESULTS

We identified two studies with a total of 100 participants for inclusion in the review. We found the overall risk of bias to be unclear in a number of domains. Neither study reported the time taken to the first INR in range. Only one study (70 participants) reported the mean time in therapeutic range as a percentage. This study found that in the group of participants deemed to have poor INR control, the addition of 150 micrograms (mcg) oral vitamin K significantly improved anticoagulation control in those with unexplained instability of response to warfarin. The second study (30 participants) reported the effect of 175 mcg oral vitamin K versus placebo on participants with high variability in their INR levels. The study concluded that vitamin K supplementation did not significantly improve the stability of anticoagulation for participants on chronic anticoagulation therapy. However, the study was only available in abstract form, and communication with the lead author confirmed that there were no further publications. Therefore, we interpreted this conclusion with caution. Neither study reported any thromboembolic events, haemorrhage, or death from the addition of vitamin K supplementation.

AUTHORS' CONCLUSIONS

Two included studies in this review compared whether the addition of a low dose (150 to 175 mcg) of vitamin K given to participants with a high-variability response to warfarin improved their INR control. One study demonstrated a significant improvement, while another smaller study (published in abstract only) suggested no overall benefit. Currently, there are insufficient data to suggest an overall benefit. Larger, higher quality trials are needed to examine if low-dose vitamin K improves INR control in those starting or already taking warfarin.

Slow versus fast subcutaneous heparin injections for prevention of bruising and site pain intensity

BACKGROUND

Heparin is an anticoagulant medication that is usually injected subcutaneously. Subcutaneous administration of heparin may result in complications such as bruising, haematoma, and pain at the injection site. One of the factors that may affect pain, haematoma, and bruising is injection speed. For patients and healthcare providers, strategies that can reduce pain and bruising are considered important. Reducing patients' discomfort and concerns whenever and wherever possible is an important aim of nursing. Several studies have been carried out to see if speed of injection affects the amount of pain and bruising where the injection is given, but results of these studies have differed and study authors have not reached a clear final conclusion. This is the first update of the review first published in 2014.

OBJECTIVES

To assess the effects of duration (speed) of subcutaneous heparin injection on pain, haematoma, and bruising at the injection site in people admitted to hospitals or clinics who require treatment with unfractionated heparin (UFH) or low molecular weight heparin (LMWH).

SEARCH METHODS

For this update, the Cochrane Vascular Information Specialist (CIS) searched the Specialised Register (last searched March 2017) and the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2). The CIS also searched trials registries for details of ongoing or unpublished studies. Review authors searched two Persian databases - Iranmedex and Scientific Information Database (SID) - as well as Google Scholar.

SELECTION CRITERIA

We sought randomised controlled trials (RCTs) comparing the effects of different durations of subcutaneous injection of heparin on pain, bruising, and haematoma at the injection site.

DATA COLLECTION AND ANALYSIS

Two review authors (MM, LJ), working independently, extracted data onto a structured form and assessed study quality. We used the criteria recommended by Cochrane to assess the risk of bias of included studies. For the outcomes, we calculated the mean difference (MD) or the standardised MD (SMD) with corresponding 95% confidence intervals (CIs). We pooled data using fixed-effect and random-effects models. We used GRADE to assess the overall quality of evidence supporting outcomes assessed in this review.

MAIN RESULTS

For this update, we identified three new studies and therefore included in the Review four studies with a total of 459 participants who received subcutaneous injections of LMWH into the abdomen. Only one trial reported the injected drug volume (0.4 mL). Owing to the nature of the intervention, it was not possible to blind participants and care givers (personnel) in any included study. Two studies described blinding of outcome assessors; therefore overall, the methodological quality of included studies was moderate. The duration of the fast injection was 10 seconds and the duration of the slow injection was 30 seconds in all included studies.Three studies reported site pain intensity after each injection at different time points. Two studies assessed site pain intensity immediately after each injection, and meta-analysis on 140 participants showed no clear difference in site pain intensity immediately post slow injection when compared to fast injection (low-quality evidence; P = 0.15). In contrast, meta-analysis of two studies with 59 participants showed that 48 hours after the heparin injection, slow injection was associated with less pain intensity compared to fast injection (low-quality evidence; P = 0.007). One study (40 participants) reported pain intensity at 60 and 72 hours after injection. This study described no clear difference in site pain intensity at 60 and 72 hours post slow injection compared to fast injection.All four included studies assessed bruise size at 48 hours after each injection. Meta-analysis on 459 participants showed no difference in bruise size after slow injection compared to fast injection (low-quality evidence; P = 0.07). None of the included studies measured the incidence of haematoma as an outcome.

AUTHORS' CONCLUSIONS

We found four RCTs that evaluated the effect of subcutaneous heparin injection duration on pain intensity and bruise size. Owing to the small numbers of participants, we found insufficient evidence to determine any effect on pain intensity immediately after injection or at 60 and 72 hours post injection. However, slow injection may reduce site pain intensity 48 hours after injection (low-quality evidence). We observed no clear difference in bruise size after slow injection compared to fast injection (low-quality evidence). We judged this evidence to be of low quality owing to imprecision and inconsistency.

Methods for administering subcutaneous heparin during pregnancy

BACKGROUND

Pregnant women with a history of venous thromboembolism (VTE), antithrombin deficiency, or other risk factors for VTE, need heparin (unfractionated heparin (UFH) or low-molecular weight heparin (LMWH)) prophylaxis, mainly through administering subcutaneously. Several methods of administering heparin (UFH or LMWH) subcutaneously have been introduced to prevent adverse pregnant outcomes. The effectiveness and safety of different methods administering subcutaneous heparin (UFH or LMWH) during pregnancy have not been systematically evaluated.

OBJECTIVES

To compare the effectiveness and safety of different methods of administering subcutaneous heparin (UFH or LMWH) to pregnant women.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2013) and reference lists of retrieved studies.

SELECTION CRITERIA

All randomised controlled trials (individual and cluster) comparing the effectiveness and safety of different methods of administering subcutaneous heparin (UFH or LMWH) during pregnancy. Studies reported only as abstracts were eligible for inclusion and would have been placed in studies awaiting assessment, pending the full publication of their results. Quasi-randomised studies and cross-over trials were not eligible for inclusion..Methods of administering subcutaneous heparin include intermittent injections versus indwelling catheters or programmable (auto) external infusion pumps, or any other devices to facilitate the subcutaneous administration of heparin (UFH or LMWH) during pregnancy.

DATA COLLECTION AND ANALYSIS

If eligible trials had been identified, trial quality would have been assessed and data extracted, unblinded by review authors independently.

MAIN RESULTS

No trials met the inclusion criteria for the review.

AUTHORS' CONCLUSIONS

There is no evidence from randomised controlled trials to evaluate the effectiveness and safety of different methods of administering subcutaneous heparin (UFH or LMWH) to pregnant women.

Interrupted versus uninterrupted anticoagulation for cardiac rhythm management device insertion

BACKGROUND

Guideline-recommended strategies to interrupt chronic anticoagulation with warfarin or direct oral anticoagulants (DOAC) during the perioperative period of cardiac implantable electronic device (CIED) surgery differ worldwide. There is uncertainty concerning the benefits and harms of interrupted and uninterrupted anticoagulation in patients undergoing CIED surgery.

OBJECTIVES

To assess the benefits and harms of interrupted anticoagulation (IAC) with either warfarin or DOAC in the perioperative period of CIED surgery versus uninterrupted anticoagulation (UAC), with or without heparin bridging, during an equivalent time frame, for CIED surgery.

SEARCH METHODS

CENTRAL, MEDLINE, Embase, Web of Science, and two trials registers were searched on 26 November 2021 together with reference checking, citation searching and contact with study authors to identify additional studies. We plan to update this review imminently.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) evaluating IAC vs. UAC in adults with a diagnosed cardiac rhythm disorder, who underwent elective CIED surgery and received at least one month of warfarin or DOAC anticoagulation. Comparisons of interest were: (1) continued warfarin vs. interrupted warfarin anticoagulation, with or without heparin bridging; and (2) continued DOAC (apixaban, betrixaban, dabigatran, edoxaban, or rivaroxaban) vs. interrupted DOAC, with or without heparin bridging.

DATA COLLECTION AND ANALYSIS

Primary outcomes were composite thromboembolic events (transient ischemic attack, ischemic stroke, deep vein thrombosis, pulmonary embolism, peripheral embolism, or valve thrombosis) and device-pocket hematoma. Secondary outcomes included individual components of composite thromboembolic events, composite bleeding events, all-cause mortality, adverse events, quality of life and days of hospitalization. Two authors independently selected studies, extracted data, and assessed the risk of bias. We assessed the certainty of evidence using GRADE. The inverse variance random-effects model was used for meta-analyses, and the DerSimonian and Laird method was used for calculating the between-study variance Tau2. Dichotomous outcomes were calculated as risk ratios (RRs) and we used mean differences (MDs) for continuous outcomes, with respective 95% confidence intervals (95% CIs).

MAIN RESULTS

We identified 10 eligible studies (2221 participants), of which one is ongoing. Of these 10 studies, six compared IAC vs. UAC with warfarin (1267 participants) and four compared IAC vs. UAC with DOAC (954 participants). Follow-up duration ranged between 0.5 to three months. The mean age of participants ranged from 68 to 76 years. Definitions of thromboembolic events, device-pocket hematoma, and bleeding events varied across studies. IAC vs. UAC with warfarin IAC with warfarin may result in little to no difference in composite thromboembolic events (RR 0.85, 95% CI 0.18 to 4.11; 5 RCTs, n = 1266; low-certainty evidence). The evidence is very uncertain about the effect of IAC on device-pocket hematoma (RR 1.87, 95% CI 0.83 to 4.22; 5 RCTs, n = 1266; very low-certainty evidence), ischemic stroke (RR 0.70, 95% CI 0.11 to 4.40; 5 RCTs, n = 1266; very low-certainty evidence) and composite bleeding events (RR 1.92, 95% CI 0.84 to 4.43; 5 RCTs, very low-certainty evidence). IAC with warfarin likely results in little to no difference in deep vein thrombosis or pulmonary embolism (0 events in both groups; 2 RCTs, n = 782; moderate-certainty evidence). IAC may result in a slight reduction of all-cause mortality (RR 0.35, 95% CI 0.04 to 2.93; 3 RCTs, n = 953; low-certainty evidence). IAC vs. UAC with DOAC IAC with DOAC may result in little to no difference in composite thromboembolic events (RR 0.98, 95% CI 0.06 to 15.63; 3 RCTs, n = 843; low-certainty evidence) and ischemic stroke (RR 0.98, 95% CI 0.06 to 15.63, 2 RCTs, n = 763; low-certainty evidence). The evidence is very uncertain about the effect of IAC with DOAC on device-pocket hematoma (RR 1.07, 95% CI 0.55 to 2.11; 4 RCTs, n = 954; very low-certainty evidence) and composite bleeding events (RR 1.07, 95% CI 0.55 to 2.06; 4 RCTs, n = 954; very low-certainty evidence). IAC may result in little to no difference in ischemic stroke (RR 0.98, 95% CI 0.06 to 15.63, 2 RCTs, low-certainty evidence). IAC likely results in little to no difference in deep vein thrombosis or pulmonary embolism (0 events in both groups; 2 RCTs, n = 763; moderate-certainty evidence). IAC may result in a slight reduction of all-cause mortality (RR 0.49, 95% CI 0.04 to 5.39; 2 RCTs, n = 763; low-certainty evidence).

AUTHORS' CONCLUSIONS

Interrupted anticoagulation in people undergoing elective CIED surgery had similar outcomes to uninterrupted anticoagulation with either warfarin or DOAC medications. Certainty of evidence was judged to be low to very low for most of the assessed outcomes. Further RCTs are particularly needed to help identify whether IAC significantly impacts the risks of thromboembolic events and device-pocket hematoma.

Non-vitamin K antagonist oral anticoagulants (NOACs) after transcatheter aortic valve replacement (TAVR): a network meta-analysis

BACKGROUND

Balancing the risk of thromboembolism and bleeding after transcatheter aortic valve replacement (TAVR) remains clinically challenging. Questions regarding the efficacy and safety of non-vitamin K oral anticoagulants (NOACs) after TAVR still need to be definitively answered.

OBJECTIVES

To evaluate the efficacy and safety of NOACs after TAVR in individuals with and without indication for anticoagulation.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Web of Science, ClinicalTrials.gov, and WHO ICTRP on 7 October 2023 together with reference checking and citation searching to identify additional studies.

SELECTION CRITERIA

We searched for randomised controlled trials (RCTs) that compared NOACs versus antiplatelet therapy or vitamin K antagonists (VKAs) after TAVR in adults with or without an indication for anticoagulation.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods and conducted random-effects pair-wise analyses and network meta-analyses (NMAs). Our primary outcomes were all-cause mortality, cardiovascular mortality, stroke, and major bleeding. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included four RCTs with 4808 participants in the NMA. Of these, one compared rivaroxaban versus antiplatelet therapy in people without an indication for anticoagulation after TAVR; one compared apixaban versus antiplatelet therapy in people without an indication for anticoagulation or versus VKA in people with an indication for anticoagulation after TAVR; one compared edoxaban versus VKA in people with an indication for anticoagulation after TAVR; and one compared edoxaban with antiplatelet therapy in people without an indication for anticoagulation after TAVR. The mean age of trial participants was 81 years. Follow-up duration ranged from 6 to 18 months. Overall, we judged the risk of bias in the included trials to be low in all domains except for blinding, which was assessed as high in all four studies. No studies evaluated dabigatran. In people without an indication for anticoagulation, rivaroxaban and apixaban may increase all-cause mortality after TAVR as compared to antiplatelet therapy (rivaroxaban: risk ratio (RR) 1.67, 95% confidence interval (CI) 1.13 to 2.46; studies = 1, participants = 1644; moderate-certainty evidence; apixaban: RR 1.71, 95% CI 0.97 to 3.02; studies = 1, participants = 1049; low-certainty evidence), while edoxaban may result in little or no difference (RR 1.59, 95% CI 0.27 to 9.36; studies = 1, participants = 229; low-certainty evidence). Low-certainty evidence suggests little or no difference between rivaroxaban, apixaban, or edoxaban and antiplatelet therapy in cardiovascular mortality (rivaroxaban: RR 1.28, 95% CI 0.78 to 2.10; studies = 1, participants = 1644; apixaban: RR 1.30, 95% CI 0.64 to 2.65; studies = 1, participants = 1049; edoxaban: RR 7.44, 95% CI 0.39 to 142.38; studies = 1, participants = 229) and between rivaroxaban or edoxaban and antiplatelets in stroke (rivaroxaban: RR 1.19, 95% CI 0.71 to 2.00; studies = 1, participants = 1644; edoxaban: RR 1.06, 95% CI 0.15 to 7.42; studies = 1, participants = 229). While rivaroxaban versus antiplatelets probably increases major bleeding after TAVR (RR 1.98, 95% CI 1.07 to 3.65; studies = 1, participants = 1644; moderate-certainty evidence), there may be little or no difference between apixaban and antiplatelet therapy (RR 1.07, 95% CI 0.70 to 1.64; studies = 1, participants = 1049; low-certainty evidence). It is unclear if edoxaban has an effect on major bleeding, although the point estimate suggests increased bleeding (versus antiplatelets: RR 2.13, 95% CI 0.54 to 8.30; studies = 1, participants = 229; low-certainty evidence). In people with an indication for anticoagulation, low-certainty evidence suggests apixaban or edoxaban may result in little to no difference in our predefined primary efficacy outcomes after TAVR when compared to VKA (all-cause mortality: apixaban: RR 1.02, 95% CI 0.59 to 1.77; studies = 1, participants = 451; edoxaban: RR 0.91, 95% CI 0.69 to 1.20; studies = 1, participants = 1426; cardiovascular mortality: apixaban: RR 1.43, 95% CI 0.76 to 2.70; studies = 1, participants = 451; edoxaban: RR 1.07, 95% CI 0.72 to 1.57; studies = 1, participants = 1426; stroke: apixaban: RR 1.28, 95% CI 0.35 to 4.70; studies = 1, participants = 451; edoxaban: RR 0.83, 95% CI 0.51 to 1.34; studies = 1, participants = 1426). While apixaban may result in a similar rate of bleeding as VKA in this population, edoxaban probably increases major bleeding after TAVR in people with an indication for anticoagulation (apixaban: RR 0.90, 95% CI 0.53 to 1.54; studies = 1, participants = 451; low-certainty evidence; edoxaban: RR 1.44, 95% CI 1.08 to 1.93; studies = 1, participants = 1426; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

In people without an indication for oral anticoagulation, rivaroxaban and apixaban may increase all-cause mortality when compared to antiplatelet therapy, while edoxaban may result in little or no difference. There might be little or no difference between rivaroxaban, apixaban, or edoxaban and antiplatelet therapy in cardiovascular mortality, and between rivaroxaban or edoxaban and antiplatelets in stroke. While rivaroxaban probably increases major bleeding following TAVR, there might be little or no difference between apixaban and antiplatelet therapy, and the effect of edoxaban on major bleeding remains unclear. In people with an indication for anticoagulation, apixaban and edoxaban may be as effective as VKA in preventing all-cause mortality, cardiovascular death, and stroke. Apixaban may lead to a similar rate of major bleeding as VKA in this population. However, edoxaban probably increases major bleeding following TAVR when compared to VKA. Our NMA did not show superiority of one NOAC over another for any of the primary outcomes. Head-to-head trials directly comparing NOACs against each other are required to increase the certainty of the evidence.

Standard- versus extended-duration anticoagulation for primary venous thromboembolism prophylaxis in acutely ill medical patients

BACKGROUND

Venous thromboembolism (VTE) includes two interrelated conditions, deep vein thrombosis (DVT) and pulmonary embolism (PE). Risk factors include dehydration, prolonged immobilization, acute medical illness, trauma, clotting disorders, previous thrombosis, varicose veins with superficial vein thrombosis, exogenous hormones, malignancy, chemotherapy, infection, inflammation, pregnancy, obesity, smoking, and advancing age. It is estimated that hospitalized patients are 100 times more likely to develop VTE and, compared with surgical patients, medical patients often have more severe forms of VTE. VTE carries a significant risk of morbidity and mortality. Prophylactic strategies, including mechanical and pharmacological methods, are recommended for patients at risk of VTE. Pharmacological prophylaxis is considered the standard practice for acutely ill medical patients at risk of developing VTE in the absence of contraindications. For hospitalized patients, the risk of VTE extends beyond hospital stay and up to 90 days, with most events occurring within 45 days of discharge. Despite that, it remains unclear whether extended-duration anticoagulation for primary VTE prophylaxis would provide benefits without added risks or harm.

OBJECTIVES

To assess the benefits and risks of standard- versus extended-duration anticoagulation for primary VTE prophylaxis in acutely ill medical patients.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialized Register, CENTRAL, MEDLINE, Embase, CINAHL and Web of Science databases, as well as the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers up to 27 March 2023. We also searched reference lists of all included studies for additional references and searched the last five years of the American Society of Hematology conference proceedings.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing standard-duration versus extended-duration anticoagulation for primary VTE prophylaxis in acutely ill medical patients (adults being treated in a medical inpatient setting).

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures set by Cochrane. At least two authors independently screened titles and abstracts for inclusion and performed data extraction. Two authors independently assessed the risk of bias (RoB) using the Cochrane RoB 2 tool. We analyzed outcomes data using the risk ratio (RR) with 95% confidence intervals (CIs). We used the GRADE approach to assess the certainty of evidence for each outcome. Our outcomes of interest were assessed in the short term (during the treatment period and within 45 days of hospitalization) and long term (assessed beyond 45 days of hospitalization). Primary outcomes were symptomatic VTE, major bleeding, and all-cause mortality. Secondary outcomes were total VTE, a composite of fatal and irreversible vascular events (including myocardial infarction, non-fatal PE, cardiopulmonary death, stroke), fatal bleeding, and VTE-related mortality.

MAIN RESULTS

A total of seven RCTs fulfilled our inclusion criteria, comprising 40,846 participants. All studies contributing data to our outcomes were at low risk of bias in all domains. Most studies reported the outcomes in the short term. Extended-duration anticoagulation, compared with standard-duration anticoagulation, for primary VTE prophylaxis in acutely ill medical patients reduced the risk of short-term symptomatic VTE (RR 0.60, 95% CI 0.46 to 0.78; standard-duration 12 per 1000, extended-duration 7 per 1000, 95% CI 6 to 10; number needed to treat for an additional beneficial outcome [NNTB] 204, 95% CI 136 to 409; 4 studies, 24,773 participants; high-certainty evidence). This benefit, however, was offset by an increased risk of short-term major bleeding (RR 2.05, 95% CI 1.51 to 2.79; standard-duration 3 per 1000, extended duration 6 per 1000, 95% CI 5 to 8; number needed to treat for an additional harmful outcome [NNTH] 314, 95% CI 538 to 222; 7 studies, 40,374 participants; high-certainty evidence). Extended-duration anticoagulation, compared with standard-duration, results in little to no difference in short-term all-cause mortality (RR 0.97, 95% CI 0.87 to 1.08; standard-duration 34 per 1000, extended-duration 33 per 1000, 95% CI 30 to 37; 5 studies, 38,080 participants; high-certainty evidence), reduced short-term total VTE (RR 0.75, 95% CI 0.67 to 0.85; standard-duration 37 per 1000, extended duration 28 per 1000, 95% CI 25 to 32; NNTB 107, 95% CI 76 to 178; 5 studies, 33,819 participants; high-certainty evidence), and short-term composite of fatal and irreversible vascular events (RR 0.71, 95% CI 0.56 to 0.91; standard-duration 41 per 1000, extended-duration 29 per 1000, 95% CI 23 to 37; NNTB 85, 95% CI 50 to 288; 1 study, 7513 participants; high-certainty evidence). Extended-duration anticoagulation may result in little to no difference in short-term fatal bleeding (RR 2.28, 95% CI 0.84 to 6.22; standard-duration 0 per 1000, extended-duration 0 per 1000, 95% CI 0 to 1; 7 studies, 40,374 participants; low-certainty evidence), and likely results in little to no difference in short-term VTE-related mortality (RR 0.78, 95% CI 0.58 to 1.05; standard-duration 5 per 1000, extended-duration 4 per 1000 95% CI 3 to 6; 6 studies, 36,170 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

In the short term, extended- versus standard-duration anticoagulation for primary VTE prophylaxis in acutely ill medical patients reduced the risk of symptomatic VTE at the expense of an increased risk of major bleeding. Extended-duration anticoagulation resulted in little to no difference in all-cause mortality. Extended-duration anticoagulation reduced the risk of total VTE and the composite of fatal and irreversible vascular events, but may show little to no difference in fatal bleeding and VTE-related mortality. Further data, with longer follow-up, are needed to determine the optimal agent and duration for primary VTE prophylaxis in acutely ill medical patients.

Bivalirudin anticoagulation for cardiopulmonary bypass: an unusual case

The standard agent used for systemic anticoagulation during cardiopulmonary bypass is heparin. Alternative methods of anticoagulation are required for patients with heparin hypersensitivity. We present the case of a patient with heparin hypersensitivity who was anticoagulated with bivalirudin during cardiopulmonary bypass for coronary artery bypass grafting. This presented unusual challenges surrounding the monitoring of anticoagulation and the method of myocardial protection.