Digitally controlled, disposable syringe inflation system, and method for monitoring, displaying balloon catheter inflation data

• US 5,385,549 A
• Filed: 03/04/1993
• Issued: 01/31/1995
• Est. Priority Date: 03/17/1989
• Status: Expired due to Term

• Current Assignee: Merit Medical Systems, Inc.
• Original Assignee: Merit Medical Systems, Inc.
• Inventors: Lampropoulos, Fred P., Foote, Jerrold L.
• Primary Examiner(s): Yasko, John D.
• Assistant Examiner(s): CERMAK, ADAM
• Application Number:
  US08/026,431
• Time in Patent Office: 698 Days
• Field of Search: 604/118-121, 604/96-103, 604/187, 604/189, 606/192-196
• US Class Current: 604/100.03
• CPC Class Codes: A61M 25/10 Balloon catheters A61M25/0125 takes precedence; embolectomy A61B17/22032; retractors A61B17/02; inflatable balloons for placing stents or stent-grafts A61F2/958 ; stomach balloons for treatment of obesity A61F5/0003; oesophagal tubes A61J15/00
• CPC Class Codes: A61M 25/10182 Injector syringes
• CPC Class Codes: A61M 25/10188 Inflation or deflation data displays
• CPC Class Codes: G01D 9/00 Recording measured values

Abstract

An electronically controlled syringe system for connection to a balloon catheter or other balloon-type member and for automatically monitoring, displaying and recording inflation data when the syringe system is used to inflate the balloon of the catheter or other balloon-type member. A syringe having a barrel and a syringe plunger is selectively operable to increase fluid pressure applied to the balloon catheter or other balloon member by sliding the plunger further into the barrel. Positive pressure applied to the balloon catheter or member is released by withdrawing the syringe plunger toward the rear of the barrel. A piezoresistive semiconductor transducer housed on the barrel of the syringe senses fluid pressure applied by the syringe. The electric signal output by the transducer is input to a controller where the signal is digitally processed so as to derive and record therefrom electronic data representing the magnitude of applied fluid pressure, and so as also to derive the length of time that fluid pressure is applied. The electronic data representing this information is automatically displayed and recorded. In one embodiment, the controller is also mounted onto the syringe barrel to provide a digitally controlled inflation syringe system that is completely self-contained, and disposable.

Claims

1. An electronically controlled syringe system for monitoring inflation of a balloon-type member and for displaying inflation data, comprising:

a syringe for connection to said member through tubing, said syringe comprising a barrel and a plunger selectively operable to inflate said member by applying fluid pressure to said member through said tubing by sliding the plunger within the barrel;

transducer means the sensing said applied fluid pressure and for outputting an electrical signal proportional to said sensed fluid pressure, said transducer means being placed in fluid communication with said syringe and the tubing connected thereto;

electronic circuit means, electrically connected to said transducer means, for receiving said electrical signal and for electronically processing said signal so as to derive and so as to display electronic data representing the magnitude of said fluid pressure applied to said member and the length of time said fluid pressure is applied to said member;

display means, electrically connected to said electronic circuit means, for outputting a visual display of the magnitude of said applied fluid pressure and the corresponding length of time said pressure is applied to said member; and

switching means, electrically connected to said electronic circuit means and said display means, for selectively switching the expression on the display means of fluid pressure values from units of atmospheres to units of pounds per square inch as desired by the user.

2. An electronically controlled syringe system the monitoring inflation of a balloon-type member and for displaying inflation data, comprising:

a syringe for connection to said member through tubing, said syringe comprising a barrel and a plunger selectively operable to inflate said member by applying fluid pressure to said member through said tubing by sliding the plunger within the barrel;

transducer means for sensing said applied fluid pressure and for outputting an electrical signal proportional to said sensed fluid pressure, said transducer means being placed in fluid communication with said syringe and the tubing connected thereto;

means for convening said signal output from said transducer means into a series of corresponding digital signals;

digital processor means for processing said digital signals so as to electronically monitor and display inflation pressure applied to said member and the duration of inflation by performing the steps of;

deriving data from said digital signals which represents a numerical value of the magnitude of said applied pressure;

deriving data from said digital signals which represent a numerical value of the duration of said inflation pressure; and

displaying said numerical values in a visually perceptible manner to a system user;

data memory means, electrically connected to said digital processor means, for storing the digital data derived by said digital processor means;

program memory means, electrically connected to said digital processor means, for storing machine readable instructions utilized by said digital processor means to carry out said programmed steps;

display means, electrically connected to said digital processor means, for outputting a visual display of the magnitude of said applied fluid pressure and the corresponding length of time said pressure is applied to said member; and

switching means, electrically connected to said electronic circuit means and said display means, for selectively switching the expression on the display means of fluid pressure values from units of atmospheres to units of pounds per square inch as desired by the user.

3. An electronically controlled syringe system for generating a series of discrete balloon catheter inflations and for displaying inflation data corresponding to each said discrete inflation, comprising:

a control syringe for connection to a balloon of said balloon catheter through tubing, said syringe comprising a barrel and a plunger selectively operable to first apply and then remove positive fluid pressures to said balloon through said tubing by sliding the plunger within the barrel;

a piezoresistive semiconductor transducer connected in fluid communication with said fluid pressures applied to said balloon such that said transducer generates an electrical signal proportional to the sensed fluid pressure;

a controller electrically connected to said transducer, said controller comprising;

means for amplifying said signal output by said transducer;

means for converting said amplified signal from an analog to a digital form;

digital processor means for processing said digital form of said signal so as to electronically monitor and display inflation pressure applied to said balloon and the duration of inflation by performing the steps of;

deriving data from said digital signals which represents a numerical value of the magnitude of said applied pressure;

deriving data from said digital signals which represent a numerical value of the duration of said inflation pressure;

electronically storing all said derived data; and

displaying said numerical values in a visually perceptible manner to a system user;

data memory means, electrically connected to said digital processor means, for storing the digital data derived by said digital processor means;

program memory means, electrically connected to said digital processor means, for storing machine-readable instructions utilized by said digital processor means;

display means the visually identifying a numerical value for each discrete inflation together with corresponding numerical values of said inflation pressures and duration thereof; and

switching means, electrically connected to said electronic circuit means and said display means, for selectively switching the expression on the display means of fluid pressure values from units of atmospheres to units of pounds per square inch as desired by the user.

4. In a system comprising an inflatable balloon member connected through tubing to a syringe barrel and wherein a plunger slidably mounted within said barrel is moveable to selectively apply and then release fluid pressures exerted on said balloon member so as to selectively inflate said balloon member one or more times, a method of monitoring and displaying inflation data comprising the steps of:

selecting a desired unit of pressure such that all the numerical values of said fluid pressures are displayed in the selected unit, wherein the unit of pressure selected may be atmospheres or pounds per square inch;

selectively increasing fluid pressure applied to the balloon member by pushing said plunger into said syringe barrel;

sensing the fluid pressure applied by said syringe and outputting an electrical signal proportional to the sensed fluid pressure;

digitally processing the output electrical signal once a selected threshold level of the applied fluid pressure is reached so as to derive electronic digital data representing the magnitude of the applied fluid pressures and the length of times said fluid pressures are applied to the balloon member;

electronically outputting a visual display of the magnitude of sensed pressure in the selected pressure units, and the corresponding length of time that said fluid pressures are applied to the balloon member; and

releasing the fluid pressure applied to the balloon member by pulling said plunger toward the rear of the syringe barrel.

5. In a system comprising a balloon catheter connected through tubing to a syringe barrel and wherein by movement of a plunger through the barrel fluid pressure applied to the balloon catheter may be selectively increased or decreased, a method of electronically monitoring and displaying the applied fluid pressure each time the balloon catheter is inflated, the method comprising the steps of:

selecting a desired unit of pressure such that all the numerical values of said fluid pressures are displayed in the selected unit, wherein the unit of pressure selected may be atmospheres or pounds per square inch;

inflating a balloon of the balloon catheter a first time by pushing the plunger into the syringe barrel so as to apply a positive inflation pressure to the balloon;

sensing any applied fluid pressure using a piezoresistive semiconductor transducer placed in fluid communication with the applied pressure, and generating at said transducer an electrical signal proportional in magnitude and duration to said applied pressure;

converting said electrical signal to a series of corresponding digital signals and inputting said digital signals to a digital processor;

processing the digital signals using said digital processor to carry out a programmed method comprising the steps of;

deriving data from said digital signals which represents a numerical value of the magnitude of said applied pressure;

deriving data from said digital signals representing a numerical value of the duration of said positive inflation pressure;

electronically storing all said derived data;

displaying said numerical values of sensed pressure in the selected pressure units, in a visually perceptible manner to a system user;

deflating the balloon by withdrawing the syringe plunger so as to remove the positive fluid pressure applied to the balloon; and

repeating each of the above-recited steps for a second inflation of the balloon.