Dual mode I. V. infusion device

A device for infusing medical solutions to a patient which comprises:

• a fluid source;
• a compressible tube connecting said fluid source in fluid communication with the patient;
• a case having means for engagingly receiving a portion of said tube therein;
• means mounted on said case and engageable with said portion of said tube for generating a moving zone of occlusion thereon to pump fluid from said source to the patient;
• a gauge mounted on said case and operatively associated with said tube to alternately measure the outside diameter of said tube at a first time when said tube downstream from said gauge is patent and at a second time when said tube upstream from said gauge is patent;
• means for comparing the measurement at the first time with the measurement at the second time to establish a differential;
• and
• means to alarm said device and cease operation when said differential attains a predetermined value.

A method for infusing I.V. medical fluids from a fluid source to a patient through an I.V. tube having a compressible pumping section which comprises the steps of:

• A. engaging said pumping section with a device comprising:
• a case;
• means for holding a portion of said compressible pumping section on said case;
• peristaltic means mounted on said case and operatively engaged with said tube to sequentially squeeze said pumping section and produce at least one moving zone of occlusion along said pumping section for infusing fluids to the patient;
• B. monitoring the fluid pressure at a fixed location of said pumping section with a gauge operatively coupled with said pumping section for sensing fluid pressure in said pumping section at said location at a first time when said I.V. tube downstream from said location is patent and at a second time when said I.V. tube upstream from said location is patent;
• C. determining a pressure differential between said first time and said second time;
• and
• D. discontinuing the infusion of fluids to the patient when said pressure differential attains a predetermined minimum value.