Anticoagulation during continuous renal replacement therapy with lepirudin in patients with heparin-induced thrombocytopenia

Introduction

Heparin-induced thrombocytopenia type II is a serious complication during heparin therapy. Treatment with lepirudin is an alternative when anticoagulation is indispensable. However, lepirudin accumulates in patients with acute renal failure treated with renal replacement therapy. This might lead to an increase in bleeding complications, longer ICU length of stay, and more therapeutic interventions. We conducted a retrospective study of all patients after cardiothoracic surgery that developed acute renal failure, treated by continuous renal replacement therapy, during a 17-month study period. We grouped the patients according to anticoagulation with heparin or lepirudin, respectively, and analyzed the groups for differences in length of ICU stay, bleeding complications, scores (APACHE II, SAPS, TISS), and mortality.

Methods

One hundred and thirty-seven (7.2%) of a total of 1888 patients were treated with renal replacement therapy. Of those, eight patients received lepirudin, due to confirmed heparin-induced thrombocytopenia, and the remaining 129 patients were treated with heparin. Continuous heparin and lepirudin treatment was adjusted to an activated partial thromboplastin time of 1.5 times baseline values. Age, sex, type of surgery, re-operation, transfusion requirements, APACHE II score, SAPS score, TISS76 score, length of ICU stay, and ICU mortality were recorded. Statistical analysis was performed by chi-square test, likelihood ratio test, and Wilcoxon–Kruskal–Wallis test, where appropriate. Data are expressed as mean ± standard deviation, or median with 25th-75th percentiles.

Results

Patients that were anticoagulated with lepirudin remained significantly longer in the ICU (18 [13.5–53.25] vs 7 [3–16.5] days; P = 0.013). Lepirudin-treated patients were transfused significantly more frequently with packed red blood cells, and pooled thrombocytes (packed red blood cells 7 [3–15] vs 17 [8.25–27] units; P = 0.037; pooled thrombocytes 3.5 [1–8.5] vs 1 [0–2] units; P = 0.025). Additionally, these patients had significantly higher TISS scores (53 [44.75–62.25] vs 50 [44–53.5] adjusted for days; P = 0.046). Age, sex, number of re-operations, APACHE II score, SAPS score, type of surgery, and mortality did not differ significantly between the groups.

Conclusion

Lepirudin treatment after cardiac surgery in patients that develop acute renal failure, treated with continuous renal replacement therapy, leads to longer ICU length of stay, higher transfusion requirements, and more therapeutic interventions, and thus higher costs.