Haemodialysis before emergency surgery in a patient treated with dabigatran

Perioperative Management of Direct Oral Anticoagulants in Intracranial Surgery

The use of direct oral anticoagulants is increasing rapidly, because of perceived benefits over older agents, such as predictable pharmacokinetics and a reduced risk of bleeding. Elderly patients, who are more likely to be prescribed these drugs, are also presenting for neurosurgical procedures more often. The combination of these factors will result in neurosurgeons and neuroanesthesiologists encountering patients prescribed direct oral anticoagulants on an increasingly frequent basis. This review provides a summary of the current evidence pertaining to the perioperative management of these drugs, in the context of elective and emergency intracranial surgery. It highlights emerging therapies, including specific antidotes, as well as areas where the evidence base is likely to improve in the future.

Impaired renal function and abnormal level of ferritin are independent risk factors of left ventricular aneurysm after acute myocardial infarction: A hospital-based case-control study

This study was performed to determine the prognostic value of glomerular filtration rate (GFR) and ferritin compromised in left ventricular aneurysm (LVA) patients who suffered acute myocardial infarction (AMI) beforehand.A hospital-based case-control study was conducted in the Department of Cardiology, First Affiliated Hospital, Zhejiang University in 2013 and 2014. Patients were divided into 3 groups according to kidney function and ferritin level. Observation outcomes include age, sex, C-reaction protein (CRP), medical history including major risk factors for CAD, ferritin and GFR, previous angina, time between MI and coronary angiography or time to rescue (TTR), and prior treatment.Around 60 patients were included in the case group (AMI with LVA) and 133 matched patients (AMI without LVA) in the control group. The prevalence of single-vessel disease (odd ratio [OR] = 2.490; 95% confidential interval [95% CI] = 1.376-4.506; P = .002), total LAD occlusion (OR = 1.897; 95% CI = 1.024-3.515; P = .041), absence of previous angina (OR = 1.930; 95% CI = 1.035-3.600; P = .037), time between myocardial infraction (MI) and coronary angiography more than 12 h (OR = 1.970; 95% CI = 1.044-3.719; P = .035), GFR less than 60 mL/min (OR = 2.933; 95% CI = 1.564-5.503; P = .001), and ferritin levels (P = .0003) were all higher in the aneurysm group compared with those in the control group. After adjustments for other variables, single-vessel disease (OR = 1.211; 95% CI = 1.080-1.342; P = .02), GFR lower than 60 mL/min (OR = 1.651; 95% CI = 1.250-2.172; P = .013), and high or low levels of ferritin (OR = 1.151; 95% CI = 1.050-1.252; P = .042) remained the independent determinants of LVA formation after AMI.Decreased GFR and abnormal ferritin levels are independent risk factors of LVA formation after AMI.

Enhanced elimination of dabigatran through extracorporeal methods

Several pharmacokinetic studies have suggested that dabigatran possesses a number of ideal properties for expedited removal via extracorporeal methods. However, this practice has not been prospectively evaluated in patients with life-threatening bleeding or requiring emergency surgery secondary to dabigatran-associated coagulopathy. The purpose of this literature review is to evaluate the published evidence surrounding extracorporeal removal of dabigatran in the setting of emergency surgery or life-threatening bleeding. A query of MEDLINE, Web of Science, International Pharmaceutical Abstracts, and Google Scholar using the terms dabigatran, dabigatran etexilate, hemodialysis, renal replacement therapy, hemorrhage, and atrial fibrillation was used to retrieve relevant literature. Furthermore, a manual search of the references of the identified literature was performed to capture additional data. Current evidence suggests that extracorporeal removal of dabigatran may play a role in the setting of life-threatening bleeding and emergent surgery. Conflicting evidence exists with regard to the potential for redistribution based on serum dabigatran concentrations. In addition, a number of practicalities must be considered before incorporating this technique in the clinical setting. Extracorporeal removal of dabigatran may be a treatment modality in selected patients who require emergency reversal.

Hemodialysis for the treatment of dabigatran-associated bleeding: a case report and systematic review

BACKGROUND

Dabigatran, a direct thrombin inhibitor, is effective for the treatment of venous thromboembolism and the prevention of stroke and systemic embolism resulting from atrial fibrillation. The most effective way of reversing the anticoagulant effect of dabigatran in patients who have bleeding complications is unknown.

OBJECTIVES

To document the clinical outcomes of patients undergoing renal replacement therapy (RRT) for dabigatran-associated bleeding.

METHODS

We searched MEDLINE and EMBASE up to May 2015. Articles were selected if the patients presented with dabigatran-associated bleeding, underwent RRT for dabigatran removal, and reported an effect on bleeding.

RESULTS

The search yielded 22 studies representing 35 unique patient cases. The median patient age was 74.1 years (range, 56-94 years). Thirteen patients (37.1%) were female, and 32 (91.4%) patients received dabigatran for atrial fibrillation. Twenty-three patients (65.7%) underwent intermittent hemodialysis, 10 patients (28.6%) underwent continuous RRT (CRRT), and two patients underwent both intermittent hemodialysis and CRRT. Following RRT, there were significant reductions in dabigatran concentrations (P = 0.001). Rebound of the dabigatran concentration was reported in 12 (57.1%) patients following cessation of RRT. Hemostasis was reportedly achieved in 24 patients (70.6%), and 10 patients (29.4%) died because of bleeding.

CONCLUSIONS

In patients with dabigatran-associated bleeding, RRT appears to be effective in reducing dabigatran concentrations, and in case reports this has been associated with a reduction in the duration and/or severity of bleeding. However, a rebound in concentrations may be seen following withdrawal of RRT, suggesting that a prolonged course of RRT may be more effective.

Venovenous haemodiafiltration for the management of dabigatran overdose in intensive care unit

Dabigatran is a direct thrombin inhibitor indicated for thromboembolism prophylaxis in patients with non-valvular atrial fibrillation. The procedure to manage dabigatran-associated haemorrhages is not well formalized. Conventional haemodialysis has been evaluated with good results. Patients with dabigatran-associated bleeding may be unstable and convective techniques like venovenous haemodiafiltration (HDF) can be interesting. We report the case of a 74-year-old, critically ill patient with haemorrhagic shock and dabigatran overexposure due to acute kidney injury. He underwent HDF and dabigatran blood concentrations decreased from 325.3 ng/mL to 160.5 ng/mL. We report here key pharmacokinetics parameters (half-life, extraction coefficient, clearance).

Balancing the risk of complications in foot and ankle surgical patients taking antithrombotic medication

This review intends to provide guidance regarding perioperative management of anticoagulation and antiplatelet drug therapy as they relate to foot and ankle surgery. Venous and arterial thromboembolism are conditions in which the blood clots inappropriately, causing considerable morbidity and mortality. With an increase in awareness of thromboembolic risk factors and expansion of therapeutic options, more patients are routinely taking antithrombotic medication. When these patients require invasive procedures, a decision needs to be made if antithrombotic medication should be held perioperatively and if additional precautions are needed in the interim. Understanding the factors affecting the management of thromboembolism during the perioperative period can reduce the potential for complications.

LEVELS OF EVIDENCE

Therapeutic, Level V: Expert opinion.

Management of gastrointestinal bleeding in patients anticoagulated with dabigatran compared with warfarin: a retrospective, comparative case review

BACKGROUND

Dabigatran etexilate, was found to be effective for stroke prevention in patients with non-valvular atrial fibrillation. Given its predictable pharmacodynamics, laboratory monitoring is not required. Moreover, the risks of overall bleeding, intracranial bleeding, and life-threatening hemorrhage from dabigatran were found to be lower than warfarin. However, a higher risk of gastrointestinal (GI) bleeding caused by dabigatran from the randomized evaluation of long-term anticoagulant therapy (RE-LY) trial has raised the concern regarding clinical outcomes of patients with GI bleeding caused by dabigatran compared with warfarin.

METHODS

We retrospectively studied patients who were hospitalized for GI bleeding from dabigatran compared with warfarin with therapeutic anticoagulation monitoring during 2009 to 2012. Initial laboratory findings at presentation, number of transfused packed red blood cells (PRBCs), acute kidney injury, clinical outcomes (e.g., hypotension, tachycardia), length of stay, and death were compared.

RESULTS

Thirteen patients taking dabigatran and 26 patients who were on warfarin with therapeutic international normalized ratio (INR) were hospitalized during the study period. Demographic data and baseline parameters between the two groups were not significantly different except for concurrent aspirin use (84.6% vs. 50%, P=0.036). Fifty-four percent of patients taking dabigatran did not have activated partial thromboplastin time (aPTT) level performed at presentation (7/13). The patients with GI bleeding from warfarin received significantly more PRBC transfusions compared with the dabigatran group (1.92±2.2 vs. 0.69±1.1 units, P=0.024). After controlling for initial hemoglobin and history of chronic kidney disease by using multivariate analysis, the patients in the warfarin group were likely to receive more PRBC. Hypotension at presentation was more common in GI bleeding caused by warfarin than dabigatran but the P value was insignificant (30.8% vs. 7.7%, P=0.11). Nevertheless, no differences in clinical outcomes or length of stay were found between the two groups.

CONCLUSIONS

From our data, the patients with GI bleeding from dabigatran were likely to receive fewer PRBC transfusions; however, clinical outcomes and length of stay were comparable to GI bleeding caused by warfarin. Our sample generalizes to an elderly population (mean age of 77.9±10 years old) with creatinine clearance (CrCl) >30 mL/min who experience GI bleeding during chronic anticoagulation.

Dabigatran anticoagulation and Stanford type A aortic dissection: lethal coincidence: Case report with literature review

BACKGROUND

Novel oral anticoagulants are now encountered in patients needing emergency surgery. Knowledge and treatment options are limited.

METHODS AND RESULT

We present the case of a 76-year-old patient who suffered from an acute Stanford type A aortic dissection, needing emergency surgical aortic repair. He was anticoagulated with dabigatran due to past atrial fibrillation. Despite haemodiafiltration, surgical revision and massive transfusion of packed red blood cells, fresh frozen plasma, platelets, coagulation factors, and recombinant factor VIIa, the patient died from intractable bleeding with sustained therapeutic levels of dabigatran.

CONCLUSION

After reviewing the literature, we summarize the limited treatment options and show possible approaches for patients treated with dabigatran needing emergency surgery.

Prothrombin complex concentrates and a specific antidote to dabigatran are effective ex-vivo in reversing the effects of dabigatran in an anticoagulation/liver trauma experimental model

Introduction

New oral anticoagulants are effective alternatives to warfarin. However, no specific reversal agents are available for life-threatening bleeding or emergency surgery. Using a porcine model of trauma, this study assessed the ability of prothrombin complex concentrate (PCC), activated PCC (aPCC), recombinant FVIIa (rFVIIa) and a specific antidote to dabigatran (aDabi-Fab) to reverse the anticoagulant effects of dabigatran.

Methods

Dabigatran etexilate (DE) was given orally for 3 days (30 mg/kg bid) and intravenously on day 4 to achieve consistent, supratherapeutic concentrations of dabigatran. Blood samples were collected at baseline, after oral DE, after intravenous dabigatran, and 60 minutes post-injury. PCC (30 and 60 U/kg), aPCC (30 and 60 U/kg), rFVIIa (90 and 180 μg/kg) and antidote (60 and 120 mg/kg) were added to blood samples ex-vivo. Coagulation was assessed by thromboelastometry, global coagulation assays and diluted thrombin time.

Results

Plasma concentrations of dabigatran were 380 ± 106 ng/ml and 1423 ± 432 ng/ml after oral and intravenous administration, respectively, and all coagulation parameters were affected by dabigatran. Both PCCs and aDabi-Fab, but not rFVIIa, reversed the effects of dabigatran on thromboelastometry parameters and prothrombin time. In contrast, aPTT was only normalised by aDabi-Fab. Plasma concentration (activity) of dabigatran remained elevated after PCC and rFVIIa therapy, but was not measureable after aDabi-Fab.

Conclusion

In conclusion, PCC and aPCC were effective in reducing the anticoagulant effects of dabigatran under different conditions, while aDabi-Fab fully corrected all coagulation measures and decreased the plasma concentration of dabigatran below the limit of detection. No significant effects were observed with rFVIIa.