A patency check protocol (150) for evaluating a patency check injection (156) is disclosed. The protocol (150) incorporates a pressure standard (152) (e.g., a pressure threshold a target pressure curve). A pressure associated with the patency check injection is monitored (160) and compared against this pressure standard (164). If a first condition is identified (166) (e.g., if the pressure threshold is reached if the monitored pressure deviates from the target pressure curve by more than a certain predetermined amount), one or more actions may be undertaken (168) (e.g., one or more notifications or alerts may be issued the flow rate may be reduced for the patency check injection the patency check injection may be suspended/terminated).
