[Hemorrhages among patients treated with low-molecular-weight heparins].
OBJECTIVE
Several cases have been reported of patients with severe hemorrhages caused by low-molecular-weight heparins (LMWH). The objective of the present report was to analyse risk factors for hemorrhage among patients diagnosed of hemorrhage due to LMWH.


METHODS
Retrospective study (1989-1999) of patients diagnosed of LMWH hemorrhages in a third-level teaching hospital. A review was made of: a) clinical records from hospital files; b) reports of adverse drug reactions from a program on intensive surveillance of hospital adverse reactions. Information was collected of clinical perameters of patients, treatment, site, and severity of hemorrhage.


RESULTS
A total of 36 patients diagnosed of LMWH hemorrhages were identified. The median age of patients was 76 years (range: 39 to 94 years). In 11 (31%) patients, hemorrhage originated during an ambulatory treatment, which prompted hospital admission. All patients had one or more risk factors for hemorrhage: age > or = 65 years (34; 94%); co-morbidities with hemorrhagic risk (28; 78%); use of platelet anti-aggregants or NSAIDs (17; 47%); length of treatment > 7 days (17; 47%) and use of anticoagulant doses (16; 44%). Hemorrhages occurred most commonly in the gastrointestinal tract and muscles (24; 67%). Most patients had major hemorrhages (26; 72%); and in 5 cases hemorrhages were fatal. In no patient was the dose adjusted by anti-Xa activity monitoring.


CONCLUSIONS
Most patients with LMWH hemorrhages have different risk factors for hemorrhage. A careful assessment of hemorrhagic risk factors on patients is needed when LMWH are used, particularly in the ambulatory setting. LMWH doses should be adjusted in patients with hemorrhagic risk factors.
Vallano Ferraz
A
A
Servicio de Farmacología Clínica. Hospital Universitari Vall d'Hebron. Departamento de Farmacología, Terapéutica y Toxicología. Universidad Autónoma de Barcelona. Barcelona. Spain. tv@icf.uab.es
Pedrós Cholvi
C
C
Montané Esteva
E
E
Bejarano Romero
F
F
López Andrés
A
A
Cereza García
G
G
Arnau de Bolós
J M
JM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced*; D006495:Heparin, Low-Molecular-Weight / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors
D006495:Heparin, Low-Molecular-Weight