Proper treatment of a patient frequently requires that a particular medicament be introduced into the body in liquid form. Continuous infusion is preferred when it is desired that the concentration be substantially constant or otherwise appropriately controlled over a given length of time. This control may be effected through a metering valve or, in certain cases, through the use of a pump. Regardless of how control is attempted, it has not been possible with prior art devices to provide accurate control over the delivery of essentially all of the large number of medicaments now in use. For this reason, a great number of infusion systems have been developed, each primarily directed towards infusion of a particular medicament.
The simplest infusion system involves a metering valve downstream of a conventional intravenous (I.V.) fluid containing container. These I.V. containers are usually attached to a support stand so that the fluid flows under gravity condition through an inclined ramp metering valve. Unfortunately, these simple systems cannot maintain constant drip rate, are cumbersome and substantially prevent ambulation of the patient, and the valves do not adequately respond to changes, such as volume changes, patient changes and the like.
Various types of pumps have also been utilized in an attempt to provide accurate infusion over a given period of time. The most common type of pump involves peristaltic action. We have found that peristaltic action is itself subject to certain difficulties because of the rolling nature of the wave, as well as the inability to accurately control the pumped volume.
As noted, each particular medicament must usually be infused with a pump system specifically designed therefor, such that a large number of infusion systems are required in a modern hospital complex. The large number of infusion pumps required may allow mistakes to occur due to the unfamiliarity of the attendant personnel with the particular pump. Naturally, each infusion pump has its own settings, connections and the like, thereby greatly increasing the amount of information which the attendant personnel must possess to adequately utilize these systems. Training of the attendant personnel is thereby complicated and only serves to increase total hospital costs.
Hospitals have recently been under great pressure to minimize costs. The ever increasing number of infusion systems only serves to increase costs, thereby adding to consumer complaints. Ambulation of the patient is one means for shortening the hospital stay, thereby one means for decreasing patient costs.
The disclosed invention is an infusion pump system and conduit which is designed to replace the large number of infusion systems presently known. The disclosed invention includes a modular infusion pump which is extremely lightweight, thereby permitting ready ambulation by the patient. Furthermore, the invention is battery powered, thereby cutting the tether to the A/C power supply system. Lastly, the disclosed invention is a positive displacement volumetric pump which operates on a known pumping volume, thereby assuring accurate delivery and includes a brake assembly to prevent reverse infusion as can occur in prior art pumps.