Calibration apparatus

• US 4,119,406 A
• Filed: 05/06/1976
• Issued: 10/10/1978
• Est. Priority Date: 05/06/1976
• Status: Expired due to Term

• Current Assignee: Miles Laboratories, Inc. (Bayer AG)
• Original Assignee: Miles Laboratories, Inc. (Bayer AG)
• Inventors: Clemens, Anton Hubert
• Primary Examiner(s): Reese, Robert M.
• Application Number:
  US05/683,806
• Time in Patent Office: 887 Days
• Field of Search: 23/253 R, 23/259, 23/253 A, 23/230 A, 23/230 R, 128/DIG. 5, 128/2 G, 128/2.05 D, 128/2 F, 128/2.05 R, 128/214 E, 137/597
• US Class Current: 422/81
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: G01N 27/3274 Corrective measures, e.g. error detection, compensation for temperature or hematocrit, calibration coding of calibration information G01N33/48771
• CPC Class Codes: Y10T 137/87249 Multiple inlet with multiple outlet
• CPC Class Codes: Y10T 436/117497 with a continuously flowing sample or carrier stream

Abstract

Calibration apparatus is described for use in a calibratable analytical system wherein a continuously flowing liquid sample, either alone or in admixture with other liquids, is normally caused to contact a sensor. The novel calibration apparatus enables diversion of said continuously flowing sample out of contact with the sensor and alternate contact of a calibration reference liquid or other calibration sample with the sensor. The calibration apparatus of the present invention is particularly useful in a system for analytical monitoring of a continuously flowing liquid blood sample obtained through a double lumen cannula inserted into a blood vessel of a human or animal subject. This apparatus permits the analytical system to be calibrated without the necessity of removing any portion of the cannula from the subject thereby avoiding the risk of loss of sterility inherent in such removal.

Claims

1. Apparatus for calibration of a sensor during use in a calibratable system for monitoring a specific characteristic of a continuously flowing blood sample comprising in combination a first peristaltic pump means for introducing a continuously flowing blood sample from a source connected thereto;

a sensor for detecting said specific characteristic, said sensor having flow path means, said first peristaltic pump means communicating with said sensor flow path means to supply a continuously flowing blood sample thereto;

a drain communicating with said sensor flow path means; and

a second peristaltic pump means communicating with said sensor flow path means for introducing a reference liquid from a source connected thereto to said sensor flow path means for contact with said sensor, said second pump means being capable when in pumping operation of introducing said reference liquid to said sensor flow path means during sensor calibration at a flow rate and pressure which is greater than the flow rate and pressure of the blood sample in the sensor flow path means from the first peristaltic pump means thus causing a diversion of the continuously flowing blood sample from the sensor to the drain during calibration of the sensor.

2. Apparatus for calibration of a sensor during use in a calibratable system for monitoring a specific characteristic of a continuously flowing blood sample comprising in combination first peristaltic pump means for introducing a continuously flowing blood sample from a source connected thereto;

second peristaltic pump means for introducing a buffer solution from a source connected thereto;

third peristaltic pump means for introducing a gas from a source connected thereto;

a manifold comprising a main conduit having an inlet portion, a helical portion and an outlet portion and a dububbler communicating with said outlet portion, with said helical portion and with an outlet for spent liquid, said inlet portion of said manifold communicating with said first, second and third peristaltic pump means;

a sensor for detecting said specific characteristic, said sensor having flow path means, said outlet portion of said manifold conduit communicating with said sensor flow path means to supply a continuously flowing blood sample thereto;

fourth peristaltic pump means for introducing a reference liquid from a source connected thereto to said sensor flow path means for contact with said sensor, said fourth pump being capable when in pumping operation of introducing said reference liquid to said sensor flow path means during sensor calibration at a flow and pressure which is greater than the flow rate and pressure of the blood sample in the sensor flow path means from the first peristaltic pump means thus causing a diversion of the continuously flowing blood sample from the sensor to the outlet for spent liquid during calibration of the sensor.