Patent ID: 8062281

Claim:
A method for injecting liquid under pressure to a patient, the method comprising: providing liquid under pressure to a patient through a length of tubing, the tubing including a pressurizing system, a first occlusion system and a regulation system located upstream from the first occlusion system, the first occlusion system and the regulation system defining an intermediate segment having an intermediate pressure, wherein the intermediate segment includes a disconnection system located upstream from the first occlusion system having an upstream piece for multiple use and a downstream piece for single use, the tubing also including a segment downstream of the first occlusion system having a downstream pressure; creating a positive pressure in the intermediate segment and the downstream segment with the pressurizing system during injecting of a liquid to a patient; and preventing backflow away from the patient and into the intermediate segment when injection to a patient is desired to be stopped, by maintaining a greater pressure in the entire intermediate segment than in the downstream segment, at least until the patient is disconnected from the tubing.