Patent GB-920584-A (GB)
Title: Apparatus for injecting or ejecting substances into and out of a laboratory animal
Inventor: STILL JOSEPH W
IPC: A61M5/00
Filed: 1960-01-26
Abstract: 920,584. Surgical syringes. DECKER CORPORATION. Jan. 26, 1960, No. 2788/60. Class 81 (2). [Also in Group XVIII] Apparatus for collecting blood samples or introducing substances into the blood of an animal comprises a blood column tube 12 for connection at one end with a blood vessel of the animal and having a terminal receptacle 20 at the other end, a plurality of blood receptacles 18 or substance containers 19 communicating with the tube at spaced intervals and actuating means associated with each receptacle or container to express substances into the tube or withdraw blood from the tube. A stainless steel Y-tube 12 which is filled with heparinized saline solution is attached to a polyethylene tube which is connected with the aorta or another blood vessel of an animal and projects from the back of its neck. Syringes 18, 19 for receiving blood samples or injecting food or drugs &c. are connected to helically arranged nipples 17 on the leg of the Y-tube. A saline supply syringe 20 and a waste collecting syringe 22 are connected to the outlets of the branch bores 14, 15 respectively of the Y-tube. The saline supply and waste collecting syringes are actuated step-bystep by a rack 47 or 52 and a pawl 48 or 53 under the control of solenoids 50, 54, respectively. Each blood sampling or food or drug supplying syringe comprises a glass barrel having a threaded ferrule for attachment to a nipple 17 and a glass plunger 28. The plunger has a magnetizable metal extension tube 38 by means of which it is withdrawn or projected under the control of a solenoid 39, 39a respectively. A ball valve 33 having a copper or synthetic resin spring-loaded stem 37, which passes through the syringe barrel and the plunger extension, is disposed in the nipple 17 and is opened under the control of a solenoid 41. The syringes 18 are operated by an electronic control unit 72 at preset times in accordance with a punched programme tape 67. Indexers 78, 82 select the syringe to be operated. When an individual syringe is selected for use, instructions are fed into the control unit from a sequencer tape 62 for the operation of the waste collecting syringe to withdraw saline solution from the Y-tube which then fills with blood from the animal, followed by operation of the solenoids 41 and 39 or 39a of the appropriate syringe for a predetermined time to open the ball valve 33 and actuate the syringe plunger so that a blood sample is withdrawn from or a food or drug is injected into the blood in the tube 12. The sequencer tape then determines the filling of the tube with saline from the syringe 20, which causes the return of blood to the animal, and the operation of the appropriate indexer to select the next syringe to be operated according to the programme. Provision is made for overriding the preset programme by instructions from an electrocardiograph 73 or an electroencephalograph 74 connected to the animal, a blood pressure measuring instrument 26 connected to the Y-tube or a radio receiver 75. A transmitter transmits signals denoting the animal's condition from the electrocardiograph, electroencephalograph and blood pressure measuring instrument.