Gima 35306, Руководство пользователя

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ENGLISH
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Patient’s inspiratory/expiratory cycle,
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Placement of catheter with relation to proximity of lung field,

The catheter itself,

The patient rhythm and hemodynamic status, and

Any other rapid IV solutions which are infused while the C.O. measurement is being performed
The following are some technique suggestions to obtain accurate C.O.:

Injectate solution must be cooler than the patient’s blood.

Inject solution rapidly and smoothly.

Inject at end expiration.
Chapter 15 Monitoring Anaesthesia Gas (AG)
15.1 Introduction
The anaesthetic gas (AG) module measures the patient’s anesthetic and respiratory gases, and incorporates the features
of the O
2
module as well.
The AG module determines the concentration of certain gases using the infrared (IR) light absorption measurement. The
gases that can be measured by the AG module absorb IR light. Each gas has its own absorption characteristic. The gas
is transported into a sample cell, and an optical IR filter selects a specific band of IR light to pass through the gas. For
multiple gas measurement, there are multiple IR filters. The higher the concentration of gas in a given volume the more
IR light is absorbed. This means that higher concentration of IR absorbing gas cause a lower transmission of IR light. The
amount of IR light transmitted after it has been passed though an IR absorbing gas is measured. From the amount of IR
light measured, the concentration of gas present can be calculated.
Oxygen does not absorb IR light as other breathing gases and is therefore measured relying on its paramagnetic properties.
Inside the O
2
sensor are two nitrogen-filled glass spheres mounted on a strong rare metal taut-band suspension. This
assembly is suspended in a symmetrical non-uniform magnetic field. In the presence of paramagnetic oxygen, the glass
spheres are pushed further away from the strongest part of the magnetic field. The strength of the torque acting on the
suspension is proportional to the oxygen concentration. From the strength of the torque, the concentration of oxygen is
calculated.
AG module can identify two anesthetic gases in a mixture automatically and distinguish between them according to their
contributions to the MAC value for display as the primary and secondary anesthetis agent.
15.2 Safety Information

Avoid explosion hazard, do not use flammable anesthetic agent such as ether and cyclopropane for this equipment.
15.3 Measurement Limitation
The following factors may influence the accuracy of measurement:

Leaks or internal venting of sampled gas

Mechanical shock

Cyclic pressure up to 10 kPa (100 cmH2O)

Other sources of interference, if any