Fluid management system for coronary intervention

A fluid injection system is disclosed The system is adapted to employ first and second injectors which may sequentially, or simultaneously, inject first and second fluids into a patient via a catheter. The first and second injectors may be power actuated. The actuation of the injectors may be controlled via a controller of the system. The user may be provided with an operator interface module to enable the control of the system to be affected during operation. A separate waste line may be provided to drain the system effectively and efficiently. A pressure sensor may be provided proximate the catheter to reduce pressure signal wave dampening and fluid waste.

FIELD OF THE DISCLOSURE

The disclosure generally relates to fluid dispensing machines and, more particularly, relates to fluid dispensing machines for use with power actuated syringes.

BACKGROUND OF THE DISCLOSURE

During medical procedures, fluids of different types need to be injected into human tissue and vascular structures. One such procedure is known as angiography. Angiography is a procedure used in the detection and treatment of abnormalities or restrictions in blood vessels, heart chambers and heart valves. During angiography, a radiographic image of a vascular structure is obtained by injecting radiographic contrast material through a catheter into such a vessel, heart chamber, or heart valve. X-rays are then passed through the region of the body in which the contrast material was injected. The X-rays are absorbed by the contrast material causing a radiographic outline or image of the blood vessel containing the contrast material. The x-ray images of the blood vessels filled with the contrast material are usually recorded on the film or videotape and displayed on a fluoroscope monitor.

The injection of the contrast or other fluids can be performed either manually or automatically. In both procedures, a catheter is inserted into a vessel, which in turn is connected to a fluid line leading to a manifold and in turn to an injector or syringe. The plunger of the syringe is then either manually or automatically depressed to inject fluid through the fluid line, the catheter, and into the patient.

In certain situations, it is necessary to dilute the concentration of contrast being injected into a patient. For example, in those patients with renal insufficiency incapable of processing concentrated contrast through their system, or in cases where a large amount of contrast is used, such as complicated coronary interventions (PTCA) or peripheral (PTA) cases with runoffs, direct injections of contrasts, are not possible. Accordingly, it is necessary to mix the contrasts and saline prior to injection to arrive at the appropriate dilution percentage. Such processes are necessarily slow and are currently difficult to achieve.

In addition, during injections, it is desirable for the physician or technician to be provided with feedback as to the pressure within the vessel. This is commonly provided by way of a pressure transducer mounted relatively close to the injection apparatus. However, since a relatively long expanse of conduit exists between the catheter and the injector, typically on the order of four feet or more, pressure waveforms must be transmitted through the fluid contained within that conduit all the way from the body of the patient, through the catheter, and back to the pressure transducer. Due to such distances, the waveforms may be substantially dampened by the time they reach the transducer thereby providing an inaccurate or poor signal for display to the physician.

Furthermore, after an injection is made, and it is desired to remove the contrast from the injection system or change the fluid being injected, it is currently necessary to evacuate or aspirate the entire injection line. It would be advantageous if the waste could be quickly removed, while at the same time limiting the total volume of waste fluid encountered by the system.

SUMMARY OF THE DISCLOSURE

In accordance with one aspect of the disclosure, an injection system is provided which comprises a first power actuated injector, a second power actuated injector, a fitting, and a catheter. The first power actuated injector is adapted to inject a first fluid through a first fluid line having a distal end, and the second power actuated injector is adapted to inject a second fluid through a second fluid line having a distal end. The fitting has first and second inputs and an output, with the distal ends of the first and second fluid lines being connected to the first and second inputs of the fitting, respectively. The catheter is connected to the fitting output.

In accordance with another aspect of the disclosure, a method of injecting fluid is provided which comprises the steps of providing a first power actuated injector, providing a second power actuated injector, connecting first and second fluid lines to a single catheter, and actuating one of the first and second power actuated injectors. The first power actuated injector is adapted to transport a first fluid from a first receptacle through the first fluid line, while the second power actuated injector is adapted to transport a second fluid from a second receptacle through the second fluid line.

These and other aspects and features of the disclosure will become more apparent upon reading the following detailed description in conjunction with the accompanying drawings.

DETAILED DESCRIPTION

Referring now to the drawings, an injection system constructed in accordance with the teachings of the disclosure is generally depicted by reference numeral20. While the system20is described herein in conjunction with angiographic procedures wherein radiopaque contrast is utilized, it is to be understood that the teachings of the disclosure can be utilized to construct injection systems for any other type of fluid as well. In the paragraphs that follow, the relative positions of the components of the system20will be described in terms of being “upstream” or “downstream” from one another. It is to be understood that if two components A and B are provided with component A being closer to a patient, component A is said to be “downstream” of component B, and component B is said to be “upstream” of component A.

The injection system20includes, in the first embodiment ofFIG. 1, a first injector22and a second injector24adapted to draw fluid from a first fluid supply26and a second fluid supply28, respectively. In the depicted embodiment, the first fluid supply26may be a supply of contrast while the second fluid supply28may be a supply of saline. The saline and contrast are directed by the first and second injectors22,24through first and second fluid lines30and32, respectively. A bubble detector33may be provided to detect and/or remove gas entrained in the liquid of supplies26and28. As used herein, solid lines are provided in the figures to illustrate fluid connections, while dashed lines are used to illustrate electrical connections.

The first and second fluid lines30,32include distal ends34,36, respectively, which may terminate at first and second inputs38,40, respectively, of a Y-shaped fitting42. The Y-shaped fitting42further includes an outlet44connected to an output conduit46. An advantage of using such a fitting having multiple inlets and one outlet is that multiple fluids can be supplied under pressure from multiple sources and be mixed in the fitting42prior to injection. Accordingly, the injected fluid can be tailored in terms of viscosity, concentration, etc., during the procedure without requiring pre-mixing of same as is required by the prior art. Control valves48and50may be provided within the first and second fluid lines30,32, respectively. It is to be understood that the fitting42need not be Y-shaped, and that in alternative embodiments may be T-shaped, or otherwise shaped to allow coupling of fluid lines as would be contemplated by one skilled in the art. Moreover, the control valves48and50may be provided in a variety of forms such as, but not limited to, check valves, pinch valves, or any other type of valve contemplated by one skilled in the art.

The output conduit46terminates at a valve52having first and second inputs54,56and an output58. The input54is connected to the output conduit46. The input56is connected to a medication supply59. The output58is connected to a conduit60which leads to a medical device62which may be a catheter, or the like.

Also depicted inFIG. 1is a waste line64having an input66connected to the output conduit46, and an output68connected to a waste receptacle70. A pump72is operatively associated with the waste line64to draw fluid from the output conduit46and any fluid lines fluidically connected to the output conduit46. It can therefore be seen that separate lines30,32and64are supplied for the contrast, saline, and waste, respectively. This is advantageous in that when it is desired, for example, to inject saline after injecting contrast, and injection can occur immediately without first clearing the system of contrast from the prior injection. This is in direct opposition to the prior art wherein the contrast existing in the line (e. g., 4-5 ccs of fluid) would have to first be injected into the patient, or cleaned, prior to saline injection. Moreover, by providing the waste line64close to the medical device62, when the device62is to be drained of waste, it can be done quickly and with far less waste. Put another way, since prior art systems drain the device using a pump (run in reverse) mounted back by the injector, not only must the device be drained with prior art systems, but the entire line connecting the injector to the device must be drained as well, which is overcome by the present disclosure. This represents not only a large volume (e. g., 4-5 ccs) of waste, but a source of delay as well.

A pressure sensor74may be positioned proximate the catheter62. The pressure sensor74is shown connected to the catheter conduit60. An advantage of positioning the pressure transducer74close to the catheter62is that, unlike prior art systems, the pressure waveforms need not be communicated all the way down the line to the injector and thus be subjected to substantial waveform dampening, but rather can be monitored before such dampening can occur and thus result in a much more accurate signal. The pressure sensor74generates a signal76representative of fluid pressure within the output conduit46. The signal76is communicated to a controller78which in turn generates a display signal78for transmission to an operator interface module79, enabling the physician or technician to monitor pressure.

In alternative embodiments, the pressure signal76may be used by the controller78in determining or modifying control signals80,82for controlling actuators84and86connected to the first and second injectors22and24, respectively. The actuators84and86may be any suitable actuating device such as, but not limited to, motor driven, hydraulically powered, or pneumatically powered plungers. However, it is to be understood that the control signals80,82are primarily generated by the operator depressing or otherwise actuating buttons, keypads, or the like for varying the ratio of a first fluid (e. g., contrast) to a second fluid (e. g., saline), and that the pressure signal76is provided mainly to enable the physician to monitor pressure.

The operator interface module88is associated with the controller78to enable a user to affect operation of the system20and provide the user with valuable feedback as to the operation of the system20. For example, the operator interface module88may include a display screen such as a glass plasma, liquid crystal, or cathode ray tube display, or the like, and/or a plurality of input/output devices such as the aforementioned keypad, buttons, mouse or the like for entering and receiving data. The controller may be electrically connected to valves48,50,90,92,94, and96to monitor the valves, or control movement of fluid flow directions.

In operation, the system20is able to inject fluid or fluids through the catheter62and into a patient (not shown). By employing the first and second injectors22and24, first and second fluids, such as saline and contrast, can be sequentially injected with substantially no down time for the system20. In addition, the saline and contrast can be simultaneously injected by simultaneously operating the first and second injectors22. This in turn forces saline and contrast into the fitting42and automatically mixes the fluids. Moreover, as opposed to existing systems which employ a single injector for contrast and a peristaltic pump for saline/flushing, the separate injector dedicated to saline injection enables smooth flow without the pulsating flow associated with peristaltic pumps.

When the system is to be drained, the separate waste line64can be utilized along with pump72to quickly and efficiently draw fluid out of the system20and ready the system24for additional injections. By providing the pressure sensor74proximate the catheter62, the signal76representative of fluid pressure within the catheter conduit60is more accurate and less susceptible to wave dampening.

Referring now toFIG. 2, an alternative embodiment of an injection system is generally referred to by reference numeral100. Wherein like elements are utilized, like reference numerals are employed. A difference in the alternative embodiment is that only a single injector22is employed. More specifically, the injector22is used to inject contrast, in the depicted embodiment, while the saline is injected by the peristaltic pump72run in reverse.

FIG. 2also depicts a possible position of the injector22and actuator84relative to an operating table102. As shown therein, the injector22and actuator may be proximate the table102, i.e., on an underside104thereof. In so doing, the system100is made more efficient in that the supply lines of the system100can be made shorter, thereby reducing the amount of contrast or other fluid needed in the system. Such placement of the injector and other equipment of the system can be employed with the first embodiment with equal efficacy.

With regard to the actual valves used to control fluid flow through the various fluid lines, any number of valve types, including but not limited to check valves, high pressure valves, rotary manifold valves, pinch valves and the like could be employed. In the embodiment ofFIGS. 3-7, a pinch valve system is disclosed.FIGS. 3-7also depict one potential type of user control incorporated within the operator interface88.

Beginning withFIG. 3, it will be noted that each valve is depicted as a pinch valve, meaning the valve includes an anvil110, and a movable wedge112adapted to move toward and away from the anvil110as by a pneumatic/hydraulic cylinder, motor or the like to pinch a flexible tube (forming the fluid line) therebetween and thus prevent fluid flow. It is to be understood that other types of pinch valves, such as those employing multiple movable elements adapted to move toward one another, are possible. For example, inFIG. 3, the contrast valve96is depicted in an open position, with the waste valve92, saline valve94, and an output valve116shown closed. The pressure valve90, as described herein, is always open except during injection (FIG. 4) to provide the user with a constant pressure reading.

With the contrast valve96open, the injector22can retract, thereby drawing contrast from supply26, through the valve96and into the injector22. The user can then adjust a control unit120of the operator interface88to specify injection as shown inFIG. 4, whereupon the contrast valve96is closed and the output valve116is opened. The injector plunger (not shown) can then advance, thereby pushing contrast from the injector22to the catheter62and patient.

FIGS. 5-7are much the same, but with the control unit120moved to positions corresponding to saline, waste, and pressure, respectively, with the corresponding valve (94,92,90) being depicted in an open position when selected with the control unit120. It is to be understood that the control unit120need not be provided by way of the rotary knob depicted but could be any other suitable mechanism enabling a setting to be selected and a corresponding valve signal to be generated. This may include, but not be limited to push buttons and toggle switches, or non-handheld units such as monitor touch screens, and the like. The valve signal generated could be used to actuate a motor (not shown) for moving the wedge112, energizing a solenoid, pressurizing a hydraulic or pneumatic cylinder, releasing a spring, or the like. Moreover, the signal could be used to manipulate the valve such that vacuum pressure created by the retracting plunger of the injector22could cause the desired valve to open. For example, the valves could be provided as normally closed valves wherein the actuation of a solenoid holds the valve open. The control signal could actuate the solenoid so as to release the valve, allowing only a spring or the like to hold the valve closed. The spring could be sized such that the vacuum pressure created by the retracting injector plunger could overcome the spring force and thereby open the valve. Other systems are certainly possible.

From the foregoing, one of ordinary skill in the art will appreciate that the present disclosure sets forth an apparatus and method for managing fluids injected and otherwise used in a medical procedure.