Venous blood reservoir with increased level and volume sensitivity

摘要

A blood reservoir which includes a primary reservoir that smoothly transitions into an outlet reservoir located beneath the primary reservoir. An inlet port permits the inflow of blood into the reservoir and an outlet port permits blood to flow out of the outlet reservoir. The primary reservoir defines an upper cavity that has first average cross sectional flow area. The outlet reservoir defines a lower cavity that has a second average cross sectional flow area which is preferably not more than one-half of the first average cross sectional flow area. The outlet reservoir therefore exhibits an increased sensitivity to blood level changes in the reservoir. The reservoir further includes features which inhibit the flow of blood from the outlet reservoir if the volume of blood in the outlet reservoir is reduced to a predetermined safety level.