Medication Summary
Drugs used in the management of chronic mesenteric ischemia (CMI) include heparin and warfarin for anticoagulation and intra-arterial papaverine for vasodilation.
Anticoagulants
Class Summary
Anticoagulants are given to prevent an acute thrombotic or embolic event.
Warfarin (Coumadin, Jantoven)
Warfarin is an anticoagulant that interferes with epoxide reductase, preventing production of vitamin K–dependent factors II, VII, IX, and X and proteins C and S. Because proteins C and S are the first factors to be inhibited, a prothrombic effect occurs during the initial few days after the start of warfarin therapy. Patients are started on heparin, then switched to warfarin when the prothrombin time (PT), activated partial thromboplastin time (aPTT), and international normalized ratio (INR) are in the therapeutic range. Duration of action is 2-5 day.
Heparin
Heparin is a sulfated mucopolysaccharide. Its anticoagulant effect is related to its ability to activate plasma antithrombin. The main role of heparin in CMI patients is to prevent thrombus propagation.
Vasodilators
Class Summary
Used during arteriogram to decrease vasospasm in occluded arteries, with the objective of improving blood flow.
Papaverine
Papaverine is a benzylisoquinoline derivative with a direct nonspecific relaxant effect on vascular, cardiac, and other smooth muscle.
Nitroprusside (Nitropress)
Nitroprusside causes peripheral vasodilation by direct action on venous and arteriolar smooth muscle, thus reducing peripheral resistance. It is commonly given intravenously because of its rapid onset and short duration of action. It is easily titratable to reach the desired effect.
Antibiotics
Class Summary
Antibiotic therapy must cover all likely pathogens in the context of the clinical setting.
Clindamycin (Cleocin)
Clindamycin is active against anaerobic gram-negative bacilli. It is a lincosamide that is useful in treating serious skin and soft tissue infections caused by most staphylococcal strains. It is also effective against aerobic and anaerobic streptococci, except enterococci. Clindamycin inhibits bacterial protein synthesis by inhibiting peptide chain initiation at the bacterial ribosome, which is where it preferentially binds to the 50S ribosomal subunit, causing bacterial growth inhibition.
Ticarcillin and clavulanate potassium (Timentin)
This drug combination inhibits the biosynthesis of cell wall mucopeptide and is effective during the stage of active growth. It consists of an antipseudomonal penicillin plus a beta-lactamase inhibitor and provides coverage against most gram positives, most gram negatives, and most anaerobes.
Metronidazole (Flagyl, Metro)
Metronidazole is an imidazole ring-based antibiotic that is active against anaerobes. It is usually given in combination with other antimicrobial agents, except in the setting of Clostridium difficile enterocolitis, where monotherapy is appropriate.
Aztreonam (Azactam)
Aztreonam is a monobactam that inhibits cell-wall synthesis during bacterial growth. It is active against aerobic gram-negative bacilli.
Cefoxitin (Mefoxin)
Cefoxitin is active against aerobic and anaerobic gram-negative bacilli. It is a second-generation cephalosporin that is indicated for management of infections caused by susceptible gram-positive cocci and gram-negative rods. Many infections caused by gram-negative bacteria, which are resistant to some cephalosporins and penicillins, respond to cefoxitin.
Cefotetan
Cefotetan is active against aerobic and anaerobic gram-negative bacilli. It is a second-generation cephalosporin that is indicated for management of infections caused by susceptible gram-positive cocci and gram-negative rods. Proper dosage and route of administration are determined on the basis of the patient's condition, the severity of the infection, and the susceptibility of the causative organism.
Meropenem (Merrem)
Meropenem is a bactericidal broad-spectrum carbapenem antibiotic that inhibits cell-wall synthesis. It is effective against most gram-positive and gram-negative bacteria.
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Angiogram of patient with chronic mesenteric ischemia. Note diffuse occlusive disease.
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Radiograph showing tortuous, dilated, meandering artery.
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Narrowing of superior mesenteric artery.
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Chronic aortic occlusion (Leriche syndrome) with acute embolic occlusion of superior mesenteric artery.
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Gas in colon wall, typical of advanced ischemia.
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Meandering artery, sign of chronic mesenteric arterial ischemia.
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Management of chronic mesenteric ischemia. Solid lines indicate accepted management plan; dashed lines indicate alternative management plan. MRA=magnetic resonance angiography; CT=computed tomography. Adapted from Gastroenterology. 2000 May; 118(5): 954-68.
