Fluid assist arrangement for determining a fluid characteristic of a fluid

A fluid assist arrangement for determining at least one fluid characteristic of a fluid in a fluid system comprising a drip chamber and a fluid tube in fluid connection with the drip chamber, wherein the fluid assist arrangement comprises an assist controller and a monitoring device, wherein the monitoring device comprising

• a body having a front side and a back side, wherein the front side comprises a body recess defining a body recess volume, and wherein the body recess is adapted to accommodate at least a portion of a drip chamber,
• one or more light emitting elements arranged to emit at least one light beam to pass at least a portion of the body recess volume, wherein the at least one light beam has a beam axis,
• one or more light receiving elements are configured to receive at least a portion of said at least one light beam and to convert said portion of said at least one light beam into an electrical signal,
• wherein the assist controller is in data communication with at least the one or more light receiving elements and is adapted to receive the electrical signal and wherein the assist controller is configured for determining at least one fluid characteristic of the fluid by the received electrical signal.