title: Evaluation of therapeutic anticoagulation with enoxaparin and associated anti-Xa monitoring in patients with morbid obesity: a case series.
abstract: Our purpose was to describe anti-Xa levels, dosage requirements, and complications associated with enoxaparin treatment doses in patients with morbid obesity. Inpatients with a BMI >40 kg/m(2) at an academic medical center prescribed therapeutic enoxaparin from 2004 to 2010 who also had an associated anti-Xa level were included in this retrospective evaluation. Twenty-six patients were identified having median weight of 162 kg (range 106-243), median BMI of 49.5 kg/m(2) (range 40.1-98.1), and median enoxaparin duration of 4 days (range 1-32). Venous thromboembolism was the most common reason for anticoagulation (n = 19, 73%). The median starting dose was 0.8 mg/kg actual body weight (range 0.51-1; absolute dose 80-150 mg) every 12 h. Twelve patients (46%) achieved a goal anti-Xa level, 10 (38%) were above goal and 4 (15%) were uninterpretable. Among the 10 patients with anti-Xa levels above goal, the median initial dose was 0.85 mg/kg (range 0.75-1) versus 0.74 mg/kg (range 0.51-1) for patients at goal with similar median peak serum creatinine (PSCr) values between these two groups (P > 0.05). No bleeding events occurred in patients achieving goal anticoagulation versus 4/10 (40%) with high anti-Xa levels (P = 0.033) with similar median PSCr between these groups. No thrombotic events occurred while on therapy. The majority in this cohort with morbid obesity achieved anti-Xa levels at or above goal at doses less than the recommended 1 mg/kg every 12 h. Bleeding events were more frequent among patients with anti-Xa levels above goal, despite similar PSCr values.
authors.affiliation: Internal Medicine, Barnes-Jewish Hospital, 216 S. Kingshighway Blvd, St. Louis, MO 63110, USA. end0164@bjc.org
authors.forename: Eli N
authors.initials: EN
authors.lastname: Deal
authors.forename: James M
authors.initials: JM
authors.lastname: Hollands
authors.forename: Jennifer N
authors.initials: JN
authors.lastname: Riney
authors.forename: Lee P
authors.initials: LP
authors.lastname: Skrupky
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Smith
authors.forename: Richard M
authors.initials: RM
authors.lastname: Reichley
mesh_terms: D000328:Adult; D000368:Aged; D019774:Blood Coagulation Factor Inhibitors / Q000097:blood*; D017984:Enoxaparin / Q000008:administration & dosage*; D005069:Evaluation Studies as Topic; D065427:Factor Xa Inhibitors; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage*; D006470:Hemorrhage / Q000097:blood / Q000188:drug therapy / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D009767:Obesity, Morbid / Q000097:blood* / Q000150:complications / Q000188:drug therapy*; D012189:Retrospective Studies; D054556:Venous Thromboembolism / Q000097:blood / Q000188:drug therapy / Q000209:etiology
chemical_list: D019774:Blood Coagulation Factor Inhibitors; D017984:Enoxaparin; D065427:Factor Xa Inhibitors; D005343:Fibrinolytic Agents