Blood pump assembly having a sensor and a sensor shield

Inventors

D'Ambrosio, Ralph Louis • Adams, Bruce • Finnegan, Michael Thomas • Spanier, Gerd • Siess, Thorsten

Assignees

Abiomed Inc

Abstract

A blood pump assembly can include various components such as a housing and a sensor configured to detect one or more characteristics of the blood. In some embodiments, the sensor can be coupled to the housing and can include a sensor membrane configured to deflect in response to a change in a blood parameter (e.g., pressure). The blood pump assembly can include a shield that covers at least a portion of the sensor membrane so as to protect the sensor from damage when the blood pump assembly is inserted through an introducer and navigated through the patient's vasculature and/or when the blood pump assembly is inserted into the heart in a surgical procedure. One or more protective layers can be deposited over the sensor membrane to prevent the sensor membrane from being dissolved through interactions with the patient's blood.

Core Innovation

A catheter-based blood pump assembly is described for pumping blood through a cannula assembly coupled to a blood pump housing component. The blood pump housing component includes a peripheral wall extending about a rotational axis of an impeller blade, and an impeller blade is rotated by a drive unit to pump blood. Blood pressure is detected from the pumped blood using an optical pressure sensor coupled to the peripheral wall.

The optical pressure sensor includes a sensor membrane configured to deflect in response to a change in pressure on the sensor membrane, and the sensor membrane is coupled to an optical fiber. The optical pressure sensor further includes a sensor visor overhanging the sensor membrane. A shield protects the sensor, and the shield includes a barrier bump and a sensor visor structure including an optional visor notch and cap.

The assembly includes blood aperture and blood recess arrangements that wash the sensor membrane with blood, in which the blood aperture is located in a blood recess in front of the sensor membrane. Smooth polished metal and biocompatible surfaces are emphasized to reduce thrombosis and blood shear during percutaneous or cardiac insertion. Protective layers are provided on shield and/or sensor regions to prevent dissolution and biological deposits, and optical sensing structures such as a Fabry-Perot resonator sensor head with a cavity and a temperature compensation portion are described.

Claims Coverage

The independent claim is clm-00001, directed to a method of detecting blood pressure using an impeller-driven blood pump and an optical pressure sensor with a deflectable membrane coupled to an optical fiber and overhung by a sensor visor. The claim coverage also adds signal transmission to a processor and specific sensor and blood-flow management structures, including glass ring, blood aperture/recess washing, barrier bump, visor notch and cap concepts, plus quantitative constraints such as sensor membrane thickness and dimensional relationships between the blood recess and the sensor.

Overall, the claim set covers measuring blood pressure in an impeller-driven blood pump using an optical pressure sensor with a deflectable sensor membrane coupled to an optical fiber, further constrained by a sensor visor overhanging the membrane. Dependent claims refine the optical sensing and blood-flow environment by adding signal transmission to a processor, a glass ring around the optical fiber, washing of the sensor membrane using a blood aperture in front of the sensor within a blood recess, and dimensional constraints such as blood recess width relative to the sensor and a maximum sensor membrane thickness of about 2 microns or less.

Stated Advantages

Documented Applications