Toxic effects of drugs used in the ICU. Anticoagulants and thrombolytics. Risks and benefits.
Anticoagulation is being used increasingly in the critical care areas. Thrombolytic therapy is now commonly used in emergency departments and coronary care units for treatment of AMI. Heparin therapy for unstable angina and for a 48 to 72 hour period following thrombolytic therapy for AMI is becoming commonplace. Beginning warfarin therapy concomitantly with heparin to decrease the total duration of heparin and the duration of hospital stay for DVT therapy is encouraged. The use of low-dose warfarin to prevent DVT in hip surgery, improve catheter patency, and prevent catheter-related subclavian thrombosis is increasing. Along with the increased use of anticoagulation must come a greater appreciation of the complications associated with the agents used, and of how to prevent or treat the hemorrhagic or thrombotic morbidity that may arise. Acute hemorrhage with thrombolytic agents must be recognized and the immediate implementation of conservative and aggressive measures begun. Heparin-induced thrombocytopenia with thrombosis is an often-unrecognized problem that may occur in 1% to 2% of heparin recipients and result in limb amputations. A delayed onset (6-10 days) requires frequent platelet counts for early diagnosis and treatment. The resurgence of warfarin use for prevention of cardiovascular and cerebrovascular disorders demands observation for skin necrosis from protein C and S inhibition. Early recognition of symptoms and syndromes associated with organ system hemorrhage in patients receiving chronic anticoagulation is imperative. The use of antagonists, such as protamine sulfate for heparin, vitamin K1 for warfarin, and antifibrinolytic drugs for thrombolytic agents, may be necessary in treating hemorrhagic events. However, their use may worsen the thromboembolic event initially treated.
Guidry
J R
JR
Clinical Pharmacy Services, Good Samaritan Regional Medical Center, Tucson, Arizona.
Raschke
R A
RA
Morkunas
A R
AR
D000925:Anticoagulants / Q000009:adverse effects* / Q000627:therapeutic use; D000075202:Contraindications; D003422:Critical Care; D005260:Female; D005343:Fibrinolytic Agents / Q000009:adverse effects* / Q000494:pharmacology; D006493:Heparin / Q000009:adverse effects / Q000627:therapeutic use; D006801:Humans; D007362:Intensive Care Units; D011247:Pregnancy; D015912:Thrombolytic Therapy / Q000009:adverse effects*; D014859:Warfarin / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use
D000925:Anticoagulants; D005343:Fibrinolytic Agents; D014859:Warfarin; D006493:Heparin