Veterinary anesthesia monitoring system

Abstract

A veterinary anesthesia monitor system useful in establishing, maintaining, and reporting upon the anesthesia gas mixture delivered to or exhaled by a patient.

Description

[0001]This application is a continuation of U.S. patent application Ser. No. 11 / 015,412, filed Dec. 17, 2004, now U.S. Pat. No. 7,997,268, issued Nov. 16, 2011, which claims the benefit under 35 U.S.C. §119(e) of U.S. provisional patent application No. 60 / 530,689, filed Dec. 17, 2003, each hereby incorporated by reference herein.I. BACKGROUND[0002]An anesthesia device which monitors the amount of anesthetic held for vaporization and the amount of anesthetic and carbon dioxide in the mixture of gases in the circular re-breathing system.[0003]During veterinary or human surgical procedures, a conventional anesthesia device entrains an amount of anesthetic into a mixture of gases utilizing an anesthetic vaporizer. The anesthetic entrained in the mixture of gases can be delivered for inhalation by a patient in a circular re-breathing system. The depth of general anesthesia depends on the partial pressure (or gas fraction) exerted by the inhalation anesthetic (or inhalation agent) on the ...

AI Technical Summary

Benefits of technology

"The invention is an anesthesia device that monitors the mixture of gases in the re-breathing circuit, which is used during anesthesia. The device includes sensors that can measure the amount of anesthetic in the circuit, the amount of carbon dioxide, the type or kind of anesthetic, and the flow rate of the gas(es) entraining the anesthetic. This allows for independent monitoring of the anesthetic and carbon dioxide levels, as well as control of various parameters such as the flow rate of gas(es) and temperature of the anesthetic. The device also includes a controller that processes the sensor data and provides visual or auditory indicia to the operator or controls various functions of the anesthesia device. Additionally, the invention includes computer hardware for storing and retrieving anesthesia profiles and programmable elements to track the anesthesia profile and ensure correct implementation. The technical effects of the invention include improved monitoring and control of anesthesia, as well as improved safety and efficiency during anesthesia procedures."

Problems solved by technology

A significant problem with conventional anesthetic delivery devices and procedures can be that the anesthetic vaporizer may not be properly readjusted after delivery of anesthetic during the induction period.

Even during resuscitation attempts oxygen delivered from the anesthesia machine can be contaminated with inhalation anesthetic because the vaporizer has been accidentally been left on the full ON position.

Another significant problem with conventional anesthesia delivery devices and procedures can be that visual observation of the amount of anesthetic in the anesthetic vaporizer can be required to ensure that the proper amount of anesthetic is held for delivery by the anesthetic vaporizer to the inhalation circuit.

However, visualization to estimate the amount of anesthetic in the anesthetic vaporizer and comparison to the prior estimated amount of anesthetic in anesthetic vaporizer to determine the amount of anesthetic delivered from the anesthetic vaporizer may not yield consistent delivery of anesthetic from the anesthetic vaporizer or the proper partial pressure of the inhalant anesthetic delivered to the patient.

Inconsistent, inaccurate, or undesired delivery rates of anesthetic from the anesthetic vaporizer or partial pressures of anesthetic inhalants delivered to the patient can result from the failure of or inconsistency of the operator.

In certain instances, the operator may simply become distracted from visualizing, or forget to visualize, the amount of anesthetic in the anesthetic vaporizer.

Also, visualization by the operator may simply be in error as to the actual amount of anesthetic in the anesthetic vaporizer.

In addition, anesthetic visualization and calibration of the anesthetic vaporizer can be complicated by the numerous different anesthetics which may be delivered to patients, each of which may have unique anesthetic characteristics (density, boiling point, vaporization rate, or the like).

In other instances, conventional vaporizers may be poorly designed contributing to operator error, fail to operate, operate out of calibration, operate inconsistently, or operate in an other undesired manner, making estimation of anesthetic delivery less consistent, less precise, or in some cases not possible at all.

Another significant problem with conventional anesthesia delivery devices and methods can be that only visualization or dependence upon calibration of the anesthetic vaporizer may used to estimate the amount of anesthetic delivered from the anesthetic vaporizer to the re-breathing system.

As discussed above, reliance on calibration or visualization to estimate the partial pressure of anesthetic in the re-breathing system may not provide information as to the actual condition of the gas mixture inhaled by the patient, or the subsequent condition of the gas mixture exhaled by the patient.

The absorbent, which initially absorbs substantially all the CO2, gradually becomes saturated until the absorbent no longer retains CO2 and levels of CO2 in the re-breathing system can rise to levels harmful to the patient.

As such, color change can be unreliable and harmful CO2 levels can build up in the re-breathing circuit of conventional anesthesia device of which the operator can be unaware resulting in harm to the patient.

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