Many medical procedures benefit from transporting fluid to or from a treatment site of a patient's body. Devices for transporting fluid in a medical procedure are generally referred to as catheters. They may be used to provide drainage or administer treatment fluids. For example, catheters may be used to drain fluids from organs or from areas of abnormal fluid collection such as in a surgical wound following a surgical procedure. Catheters may also be used to deliver fluid to a treatment site to provide a vast range of therapies from cancer treatment to nutritional supplementation. A few exemplary therapies include stimulating tissue growth, administering antibiotics, flushing away impurities, killing or halting the reproduction of cancer cells, and relieving pain.
Catheters may be used in gravity driven arrangements such as with a collection container located below the treatment site or a medication container located above the treatment site. Likewise, catheters may be used in pressurized arrangements. For example, suction may be applied to a drainage catheter to draw fluids away from the treatment site. Suction devices may include elastomeric bulbs, spring actuated bellows, electromechanical vacuum pumps, and other known medical suction devices. Pressurized fluid may also be delivered through a catheter to the treatment site. For example, fluid infusion devices may include manual syringes, elastomeric infusion devices, spring loaded infusion devices, electromechanical infusion devices, and other known infusion devices.
Typical prior catheters are linear devices having one or more openings formed along a portion of their length through which fluid passes. They often perform poorly due to an inability to drain fluids from or deliver fluids to a sufficiently large area to encompass the entire treatment site. In addition, tissue folds and tissue apposition further affect the movement and collection of fluid making it difficult for prior catheters to adequately address the treatment site. Prior catheters also indiscriminately aspirate or infuse the tissue surrounding the catheter with no ability to target or exclude specific areas. Indiscriminate aspiration or infusion may not provide the desired treatment and it may cause undesired interactions or harm to tissues not intended to be targeted by, for example, suction or treatment fluid. For example, anesthetics are sometimes infused into a surgical wound to provide post-surgical pain relief to disrupted tissues. It is undesirable for motor nerve roots to be anesthetized during pain treatment.