TY - JOUR
T1 - Standard prophylactic enoxaparin dosing leads to inadequate anti-Xa levels and increased deep venous thrombosis rates in critically Ill trauma and surgical patients
AU - Malinoski, Darren
AU - Jafari, Fariba
AU - Ewing, Tyler
AU - Ardary, Chris
AU - Conniff, Heather
AU - Baje, Mark
AU - Kong, Allen
AU - Lekawa, Michael E.
AU - Dolich, Matthew O.
AU - Cinat, Marianne E.
AU - Barrios, Cristobal
AU - Hoyt, David B.
PY - 2010/4
Y1 - 2010/4
N2 - BACKGROUND: Deep venous thromboses (DVT) continue to cause significant morbidity in critically ill patients. Standard prophylaxis for high risk patients includes twice-daily dosing with 30 mg enoxaparin. Despite prophylaxis, DVT rates still exceed 10% to 15%. Anti-Xa levels are used to measure the activity of enoxaparin and 12-hour trough levels ≤0.1 IU/mL have been associated with higher rates of DVT in orthopedic patients. We hypothesized that low Anti-Xa levels would be found in critically ill trauma and surgical patients and that low levels would be associated with higher rates of DVT. METHODS:: All patients on the surgical intensive care unit (ICU) service were prospectively followed. In the absence of contraindications, patients were given prophylactic enoxaparin and anti-Xa levels were drawn after the third dose. Trough levels ≤0.1 IU/mL were considered low. Screening duplex exams were obtained within 48 hours of admission and then weekly. Patients were excluded if they did not receive a duplex, if they had a prior DVT, or if they lacked correctly timed anti-Xa levels. DVT rates and demographic data were compared between patients with low and normal anti-Xa levels. RESULTS:: Data were complete for 54 patients. Eighty-five percent suffered trauma (Injury Severity Score of 25 ± 12) and 74% were male. Overall, 27 patients (50%) had low anti-Xa levels. Patients with low anti-Xa levels had significantly more DVTs than those with normal levels (37% vs. 11%, p = 0.026), despite similar age, body mass index, Injury Severity Score, creatinine clearance, high risk injuries, and ICU/ventilator days. CONCLUSION:: Standard dosing of enoxaparin leads to low anti-Xa levels in half of surgical ICU patients. Low levels are associated with a significant increase in the risk of DVT. These data support future studies using adjusted-dose enoxaparin.
AB - BACKGROUND: Deep venous thromboses (DVT) continue to cause significant morbidity in critically ill patients. Standard prophylaxis for high risk patients includes twice-daily dosing with 30 mg enoxaparin. Despite prophylaxis, DVT rates still exceed 10% to 15%. Anti-Xa levels are used to measure the activity of enoxaparin and 12-hour trough levels ≤0.1 IU/mL have been associated with higher rates of DVT in orthopedic patients. We hypothesized that low Anti-Xa levels would be found in critically ill trauma and surgical patients and that low levels would be associated with higher rates of DVT. METHODS:: All patients on the surgical intensive care unit (ICU) service were prospectively followed. In the absence of contraindications, patients were given prophylactic enoxaparin and anti-Xa levels were drawn after the third dose. Trough levels ≤0.1 IU/mL were considered low. Screening duplex exams were obtained within 48 hours of admission and then weekly. Patients were excluded if they did not receive a duplex, if they had a prior DVT, or if they lacked correctly timed anti-Xa levels. DVT rates and demographic data were compared between patients with low and normal anti-Xa levels. RESULTS:: Data were complete for 54 patients. Eighty-five percent suffered trauma (Injury Severity Score of 25 ± 12) and 74% were male. Overall, 27 patients (50%) had low anti-Xa levels. Patients with low anti-Xa levels had significantly more DVTs than those with normal levels (37% vs. 11%, p = 0.026), despite similar age, body mass index, Injury Severity Score, creatinine clearance, high risk injuries, and ICU/ventilator days. CONCLUSION:: Standard dosing of enoxaparin leads to low anti-Xa levels in half of surgical ICU patients. Low levels are associated with a significant increase in the risk of DVT. These data support future studies using adjusted-dose enoxaparin.
KW - Anti-Xa levels
KW - Critical care
KW - Low-molecular weight heparin
KW - Venous thrombosis
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U2 - 10.1097/TA.0b013e3181d32271
DO - 10.1097/TA.0b013e3181d32271
M3 - Article
C2 - 20386282
AN - SCOPUS:77951082865
SN - 0022-5282
VL - 68
SP - 874
EP - 879
JO - Journal of Trauma - Injury, Infection and Critical Care
JF - Journal of Trauma - Injury, Infection and Critical Care
IS - 4
ER -