An assessment of published pediatric dosage guidelines for enoxaparin: a retrospective review.
OBJECTIVE
To evaluate the ability of published dosage guidelines for enoxaparin to achieve therapeutic anticoagulation and to determine whether the routine monitoring of anti-Xa levels is still necessary at a tertiary care pediatric institution.


METHODS
Consecutive charts and laboratory records were reviewed for all patients receiving treatment doses of enoxaparin for thrombosis in the authors institution over a 4-year period (1998-2002).


RESULTS
Sixty-six percent (25/38) of the anti-Xa levels were within the recommended therapeutic range (0.5-1.0 [+/- 10%] U/mL) after two doses. The success rates of achieving therapeutic levels were 1/6, 2/3, 6/9, 10/11, and 6/9, for patients 2 months or younger, more than 2 months to 1 year, more than 1 year to 6 years, more than 6 years to 12 years, and more than 12 years of age, respectively. Patients with cardiac or renal disease were more likely to achieve high anti-Xa levels. Thirty-seven percent of patients reported adverse effects. The most common effects were injection site-related bruising and minor bleeding. One patient experienced a major bleed that was not life-threatening.


CONCLUSIONS
Most patients achieved therapeutic anticoagulation when dosed according to the published guidelines. Children with cardiac conditions or renal insufficiency or those younger than 2 months were more likely to require dosage adjustments to achieve the therapeutic range. Routine monitoring of anti-Xa levels is still necessary in these patient populations, particularly when the early establishment of therapeutic anticoagulation may be critical. Enoxaparin appears to be well tolerated in the authors' patient population.
Ho
Sharon H
SH
Department of Pharmacy, British Columbia's Children's Hospital, Vancouver, British Columbia, Canada. sho@cw.bc.ca
Wu
John K
JK
Hamilton
Donald P
DP
Dix
David B
DB
Wadsworth
Louis D
LD
D000293:Adolescent; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D017984:Enoxaparin / Q000008:administration & dosage* / Q000009:adverse effects; D015951:Factor Xa / Q000032:analysis; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008500:Medical Records Department, Hospital; D012189:Retrospective Studies; D013927:Thrombosis / Q000188:drug therapy* / Q000378:metabolism / Q000517:prevention & control
D000925:Anticoagulants; D017984:Enoxaparin; D015951:Factor Xa