Anticoagulation: Updated Guidelines for Outpatient Management

Anticoagulation therapy is recommended for preventing, treating, and reducing the recurrence of venous thromboembolism, and preventing stroke in persons with atrial fibrillation. Direct oral anticoagulants are first-line agents for eligible patients for treating venous thromboembolism and preventing stroke in those with nonvalvular atrial fibrillation. Vitamin K antagonists are recommended for patients with mechanical valves and valvular atrial fibrillation. Vitamin K antagonists inhibit the production of vitamin K-related factors and require a minimum of five days overlap with parenteral anticoagulants, whereas direct oral anticoagulants directly inhibit factor II or factor Xa, providing more immediate anticoagulation. The immediate effect of direct oral anticoagulants permits select patients at low risk to initiate treatment in the outpatient setting for venous thromboembolism, including pulmonary embolism. Low-molecular-weight heparin continues to be recommended as a first-line treatment for patients with venous thromboembolism and active cancer, although there is growing evidence of effectiveness for the use of direct oral anticoagulants in this patient population. Validated bleeding risk assessments such as HAS-BLED should be performed at each visit and modifiable factors should be addressed. Major bleeding should be treated with vitamin K and 4-factor prothrombin complex concentrate for patients already being treated with a vitamin K antagonist. Idarucizumab has been effective for reversing the anticoagulant effects of dabigatran, and andexanet alfa has been effective for reversing the effects of rivaroxaban and apixaban.

Subacute management of ischemic stroke

Ischemic stroke is the third leading cause of death in the United States and a common reason for hospitalization. The subacute period after a stroke refers to the time when the decision to not employ thrombolytics is made up until two weeks after the stroke occurred. Family physicians are often involved in the subacute management of ischemic stroke. All patients with an ischemic stroke should be admitted to the hospital in the subacute period for cardiac and neurologic monitoring. Imaging studies, including magnetic resonance angiography, carotid artery ultrasonography, and/or echocardiography, may be indicated to determine the cause of the stroke. Evaluation for aspiration risk, including a swallowing assessment, should be performed, and nutritional, physical, occupational, and speech therapy should be initiated. Significant causes of morbidity and mortality following ischemic stroke include venous thromboembolism, pressure sores, infection, and delirium, and measures should be taken to prevent these complications. For secondary prevention of future strokes, antiplatelet therapy with aspirin should be initiated within 24 hours of ischemic stroke in all patients without contraindications, and one of several antiplatelet regimens should be continued long-term. Statin therapy should also be given in most situations. Although permissive hypertension is initially warranted, antihypertensive therapy should begin within 24 hours. Diabetes mellitus should be controlled and patients counseled about lifestyle modifications to reduce stroke risk. Rehabilitative therapy following hospitalization improves outcomes and should be considered.

Gadolinium-associated nephrogenic systemic fibrosis

Nephrogenic systemic fibrosis is a progressive, potentially fatal multiorgan system fibrosing disease related to exposure of patients with renal failure to the gadolinium-based contrast agents used in magnetic resonance imaging. Because of this relationship between nephrogenic systemic fibrosis and gadolinium-based contrast agents, the U.S. Food and Drug Administration currently warns against using gadolinium-based contrast agents in patients with a glomerular filtration rate less than 30 mL per minute per 1.73 m2, or any acute renal insufficiency related to the hepatorenal syndrome or perioperative liver transplantation. There have been reports of nephrogenic systemic fibrosis developing in patients not exposed to gadolinium-based contrast agents, but most patients have the triad of gadolinium exposure through contrast-enhanced magnetic resonance imaging, renal failure, and a proinflammatory state, such as recent surgery, endovascular injury, or sepsis. Development of nephrogenic systemic fibrosis among patients with severe renal insufficiency following exposure to gadolinium-based contrast agents is approximately 4 percent, and mortality can approach 31 percent. The mechanism for nephrogenic systemic fibrosis is unclear, and current treatments are disappointing. Prevention with hemodialysis immediately following gadolinium-based contrast agents has been recommended, but no studies have shown this to be effective. Because of the large number of patients with clinically silent renal impairment and the serious consequences of nephrogenic systemic fibrosis related to gadolinium exposure, physicians should use alternative imaging modalities for patients who are at risk.

Managing CAP: an evidence-based algorithm

The 2007 guidelines from the Infectious Diseases Society of America/American Thoracic Society are a blend of level-of-evidence strength and consensus opinion--a unified, evidence-based document. These new recommendations address prior discrepancies between the 2 specialties. We developed a CAP treatment algorithm based on the new advisory.