Patent ID: 8348896

Claim:
A power injector, comprising: a powerhead; a syringe plunger drive assembly; patency check logic configured to execute a patency check injection to assess for both blockage in a flowpath to a patient's vein and existence of an extravasation condition where fluid is being introduced into a patient's tissue instead of a vein, wherein said patency check logic comprises a pressure standard; pressure monitoring logic, wherein an output from said pressure monitoring logic is provided to said patency check logic for comparison with said pressure standard, wherein said patency check logic is configured to identify an existence of a first condition, wherein said first condition is either when a monitored pressure during a patency check injection reaches or exceeds a pressure threshold, or when a monitored pressure during a patency check injection deviates from a target pressure curve by more than a certain amount; and injection protocol logic, separate from said patency check logic, configured to execute an injection protocol after said patency check logic executes a patency check injection, wherein said injection protocol logic comprises a comparator, wherein a first input to said comparator comprises a pressure from a patency check injection when said patency check logic failed to identify an occurrence of said first condition, and wherein a second input to said comparator comprises a monitored pressure during a subsequent execution of an injection protocol.