(129) Sodium Bicarbonate Versus Heparin Purge Solutions in Patients With an Impella Device

Introduction: The Impella system is used in cardiogenic shock to augment cardiac output and improve hemodynamic stability. To prevent device thrombosis and malfunction, patients are treated with systemic unfractionated heparin (UFH) along with UFH in the device purge solution. Sodium bicarbonate (NaHCO3) purge solutions are a newer alternative to UFH purge solutions, which prevents pump thrombosis without increasing overall UFH exposure. The purpose of this study is to evaluate safety outcomes of NaHCO3 versus UFH purge solutions in patients with an Impella device.

Methods: This retrospective review was conducted at Texas Health Presbyterian Dallas. Adult patients with an Impella device who received either UFH or NaHCO3 based purge solutions were included. The primary outcome was incidence of bleeding, as defined by the TIMI criteria. Bleeding events were subdivided into major (fatal or intracranial bleeding or clinically overt signs of hemorrhage with a ≥5 g/dL hemoglobin drop), minor (clinically overt signs of bleeding with a hemoglobin drop of 3 to < 5 g/dL), and minimal (any clinically overt sign of hemorrhage with a < 3 g/dL hemoglobin decrease). Secondary outcomes included incidence of thrombocytopenia (platelet count < 100 k/µL) and incidence of proven or suspected pump thrombosis, defined as the need for alteplase in the purge solution.

Results: An analysis of 32 patients was conducted (16 patients in each group). The average duration of Impella use was 108 ± 65 hours in the NaHCO3 group and 114 ± 69 hours in the UFH group (p=0.79). Each group had a total of 7 bleeding events, with no major bleeding in either group. The NaHCO3 group had 1 minor bleed versus 4 minor bleeds in the UFH arm (p=0.27). There were 6 minimal bleeds in the NaHCO3 arm and 3 in the UFH arm (p=0.26). Thrombocytopenia was significantly lower in the NaHCO3 group (13% vs 28%, p=0.04). There was no difference in the rate of suspected thrombosis, as alteplase was used in one patient in each group.

Conclusions: This data provides further support for NaHCO3 as an alternative Impella purge solution to UFH. In this study, NaHCO3 demonstrated a significant decrease in incidence of thrombocytopenia with a trend toward less severe bleeding events.