Oral anticoagulation in the hospital: analysis of patients at risk.
Warfarin is one of the most commonly used medications associated with adverse events. Warfarin therapy is often initiated or continued in the hospital, yet hospitalization increases the risk of poor anticoagulation control with warfarin. To help understand this, we retrospectively reviewed the records of patients admitted to our hospital during a 6-month period who were given at least one dose of warfarin. To explore factors that may have contributed to poor anticoagulation control, we compared characteristics of patients with an international normalized ratio (INR) ≥ 5 at some point during hospitalization with those of a group of matched controls who also received warfarin and had INR <5. Among the 35 patients identified who had an INR ≥ 5, concomitant use of antibiotics was more common than among 105 matched controls; improper warfarin dosing also appeared to contribute to the high INRs. These findings indicate possible targets for intervention to improve patient safety.
Dawson
Nancy L
NL
Division of Hospital Medicine, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA. dawson.nancy11@mayo.edu
Klipa
Dusko
D
O'Brien
Angela K
AK
Crook
Julia E
JE
Cucchi
Melanie W
MW
Valentino
Alden K
AK
D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage / Q000493:pharmacokinetics*; D005260:Female; D006760:Hospitalization; D006801:Humans; D019934:International Normalized Ratio / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014859:Warfarin / Q000008:administration & dosage / Q000493:pharmacokinetics*
D000925:Anticoagulants; D014859:Warfarin
Ann Pharmacother. 2004 Dec;38(12):2115-21
15522981
Ann Intern Med. 1997 Jan 15;126(2):133-6
9005747
Lancet. 1996 Aug 17;348(9025):423-8
8709780
Am J Cardiol. 2006 Aug 15;98(4):535-7
16893712
Ann Pharmacother. 2000 May;34(5):567-72
10852081
Pharmacotherapy. 2004 Aug;24(8):953-63
15338843
JAMA. 2002 Apr 3;287(13):1690-8
11926893
Ann Intern Med. 2003 May 6;138(9):714-9
12729425
Thromb Res. 2007;119(6):705-14
16844204
Chest. 2008 Jun;133(6 Suppl):71S-109S
18574259
Arch Intern Med. 1999 Jan 11;159(1):46-8
9892329
J Gen Intern Med. 2005 Jul;20(7):653-6
16050864