Gima 35145, Руководство пользователя

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Note : The current C.O. measurement result will be displayed in the table “Examin. records” and saved in histo-
ry records as well. When the device is shutdown, the content listed in the table “Examin. records” will be lost,
but the history records still exists in the database. The history record includes patient ID, measuring time, TI,
TB, C.O., C.I., and BT waveform as well.
• Average C.I.(l/min/m
2
) : the calculated average C.I. for the past examination records.
•
Average C.O.(l/min)
: the calculated average C.O. for the past examination records.
You can press “ ” button to delete the record if the tolerance is too large.
14.6 Factors Affecting C.O.Measurement
• Heart
A. Preload: the blood volume in the ventricle at the end of diastolic phase, which is related with the volume of
venous return and the residual blood. Normally the pulmonary capillary wedge pressure (PCWP, its normal
value is 6-12mmHg, or 0.8-1.6kPa) is regarded as the reliable indication for the preload in right ventricle.
B. Afterload: the resistance against blood ejection.
C. The myocardial contraction and its harmonization, the heart compliance and heart rate.
• Monitor
The type of catheter, the correction constant of this catheter, the temperature, volume and speed of injection.
• Temperature of injectate solution,
• Volume of injectate solution,
• Patient’s baseline blood temperature,
• Patient’s inspiratory/expiratory cycle,
• 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 meas-
urement. The gases that can be measured by the AG module absorb IR light. Each gas has its own absorp-
tion 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 paramag-
netic 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 pres-
ence of paramagnetic oxygen, the glass spheres are pushed further away from the strongest part of the mag-
netic 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 accord-
ing 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.