Recent studies have identified that a significant cause of morbidity and mortality in women, elderly, and patients with renal failure is the failure to consider renal insufficiency in dosing certain anticoagulants and anti-platelet medications, resulting in bleeding complications. Medications should be based on creatinine clearance, NOT SERUM CREATININE. When the creatinine clearance is < 30 mL/min, the dose of any renally-excreted medications should be decreased.
For example, an 85 yo woman that is 110 lbs and has a serum creatinine of 1.2 (sounds normal!) actually has a creatinine clearance < 30, which means that she has relative renal insufficiency. Her dosages of medications (e.g. enoxaparin) should be adjusted for this.
Creatinine clearance can easily be calculated via computer programs that you can "google" (e.g. just google "creatinine clearance calculation"). If you enter the patient's gender, age, weight, and serum creatinine, the programs will calculate the value for you.
