Enoxaparin dose reduction for thrombocytopenia in patients with cancer: a quality assessment study

Abstract

The development of thrombocytopenia in the setting of therapeutic anticoagulation for venous thromboembolic disease (VTE) is common in cancer patients, but guidelines for management are based on limited past data and have not been validated. In 2011, Memorial Sloan Kettering Cancer Center (MSKCC) implemented the following guidelines in this setting: administer full dose enoxaparin for a platelet count > 50,000/mcL, half-dose enoxaparin for a platelet count of 25,000-50,000/mcL, and hold anticoagulation for a platelet count < 25,000/mcL. We now report validation of safety and efficacy of these guidelines. As a Quality Assessment Initiative, we evaluated our guidelines for adult cancer patients at MSKCC who were on therapeutic-dose enoxaparin for VTE during the years 2011 through 2013 and experienced at least one 7-day period of thrombocytopenia (platelet count ≤ 50,000/mcL). We assessed adherence to the enoxaparin dose modification guidelines, major bleeding, clinically relevant non-major bleeding, recurrent VTE, and mortality during the thrombocytopenic episodes. We identified 99 patients with 140 episodes of thrombocytopenia of 7 or more days. The median duration of these thrombocytopenic episodes was 12 days. The enoxaparin dose was modified in 133 of the 140 episodes (95%), reflecting satisfactory adherence to our institutional guidelines. There were no recurrent VTE events or major bleeding episodes when the anticoagulant dose was reduced or held. In this cohort, there was only one major bleeding episode, a trauma-associated retroperitoneal hemorrhage that occurred on the third day of a thrombocytopenic episode, prior to enoxaparin dose modification. There were 13 clinically relevant non-major bleeding episodes. Lastly, 10 patients died of cancer-related causes during an episode of thrombocytopenia. This Quality Assessment Initiative supports the safety and efficacy of our guidelines for therapeutic enoxaparin dose modification.

Keywords: Anticoagulation; Cancer; Thrombocytopenia; Thrombosis.

Fig. 1

Mean thrombocytopenic episode-specific platelet counts according to management. The top of a box represents the 3rd quartile, while the bottom corresponds to the 1st quartile and the line within the box is the median. Upper whiskers correspond to the maximum value which does not exceed the 3rd quartile plus 1.5 times the interquartile range and lower whiskers are situated at the minimum value which is not lower than 1st quartile minus 1.5 times the interquartile range. Circles outside the whiskers represent individual outliers