Automatic blood sampling system and method

• US 4,127,111 A
• Filed: 10/26/1976
• Issued: 11/28/1978
• Est. Priority Date: 10/26/1976
• Status: Expired due to Term

• Current Assignee: Free World Trust
• Original Assignee: Roland A. Drolet
• Inventors: Drolet, Roland A.
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): Jaworski, Francis J.
• Application Number:
  US05/735,811
• Time in Patent Office: 763 Days
• Field of Search: 128/2 G, 128/214 B, 128/214 E, 128/2 F, 23/230 B, 23/253 R, 73/425.4 R, 73/425.4 P, 356/39-42
• US Class Current: 600/573
• CPC Class Codes: A61B 5/145 Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissuemeasuring of blood pressure or blood flow A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• CPC Class Codes: A61B 5/15003 for venous or arterial blood
• CPC Class Codes: A61B 5/150229 Pumps for assisting the blood sampling
• CPC Class Codes: A61B 5/150992 Blood sampling from a fluid line external to a patient, such as a catheter line, combined with an infusion line; blood sampling from indwelling needle sets, e.g. sealable ports, luer couplings, valves tubing connectors and couplings A61M39/00
• CPC Class Codes: A61B 5/155 Devices specially adapted for continuous or multiple sampling, e.g. at predetermined intervals devices loaded with multiple lancets simultaneously A61B5/15146
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: G01N 35/1097 characterised by the valves valves in general F16K

Abstract

An automatic blood sampling system and method which are characterized by preventing the transmission of electric shocks to the patient, by the use of only very small blood samples, by evacuating the used blood samples to waste and thus permitting the conduct of destructive tests on the samples, and by automatic and safe cleaning and rinsing of the tubing. This system distinctively defines a pair of mini-bypasses for the blood of a patient to produce blood circulation by-passing the blood stream of the patient and to withdraw the blood samples from the mini-bypasses, upon command from an automatic blood analyser and actuation by a logic circuit. The latter actuates the necessary electromagnetic valves by a binary coding corresponding to the "on" and "off" states respectively and to produce BLOOD SAMPLING, STANDBY, WASTE, WASH and FEED SAMPLE states of actuation of the valves in response to changes in the states of operation of the automatic blood analyser.

Claims

1. A system for automatic sampling of blood and for the automatic feeding of a measured volume of blood to an automatic blood analyser, comprising a tubing having means at both ends for communicating said tubing with two spaced points of a blood vessel of a patient to establish a partial bypass, a power-operated pump means to continuously circulate blood at a constant rate of flow through said tubing by extracting blood from and returning it to said blood vessel, a blood sample withdrawal tubing adapted to be connected at one end to said analyzer, a compressed fluid source connected to the other end of said withdrawal tubing, a branch line tubing interconnecting intermediate points of said partial bypass tubing and of said withdrawal tubing, a first electromagnetic valve in said branch line tubing, a second electromagnetic valve in said withdrawal tubing serially mounted intermediate said fluid source and said branch line, and an electric command circuit means electrically connected to said two valves and giving timed commands to said valves causing opening of said first valve for a predetermined time to allow discharge of a predetermined volume of blood through said branch line within said withdrawal tubing, while said second valve is closed, then causing closing of said first valve and subsequent opening of said second valve, whereby said fluid under pressure pushes into said analyzer the measured quantity of blood in said withdrawal tubing.

2. A system as claimed in claim 1, further including a second branch line opening to waste and connected to said withdrawal tubing intermediate said first branch line and said other end of said withdrawal tubing, and a third electromagnetic valve in said second branch line, said electric command circuit means also electrically connected to said third valve and giving timed command to said third valve to cause the same to be in closed position when either one of said first and second valves are open and to cause opening of said third valve when both said first and second valves are closed, to thus allow the analyzer to clean the withdrawal tubing and to evacuate the content of the same through said second branch line to waste.