Fluke-biomedical MPS450 User Manual download pdf (Page 68)

MPS450

Operators Manual

2-36

Cardiac Output

Cardiac output is a term encompassing blood flow, pulse rate, and other vascular-related

elements. Of the entire circulatory system, cardiac output is arguably the most important

single factor for health since it controls the degree of blood being received by every other

tissue in the body. Diseases of the heart can cause a decrease of cardiac output, leading to

a condition of insufficient nutrition for the body cells. Cardiac output is expressed as the

measure of blood pumped out of the heart each minute, also called the heart-minute

volume (HMV).

One method of determining cardiac output is to measure the transference of heat in the

blood through a method called thermodilution. Thermodilution is the measurement of the

temperature change caused by the injection into the heart of a series of cold or room-

temperature solutions (such as a saline solution) into the heart. A thermistor (as integrated

into the distal lumen port of a Swan-Ganz catheter) measures the average change in blood

temperature. From this information, a determination can be made as to ventricular blood

volume and cardiac output.

The MPS450 simulates blood cooling, as the result of an injectate, to below-normal

temperatures. On most monitors, the blood temperature curve is in the positive direction,

even though the blood is cooling. Following the simulated cardiac-output test, ECG

reverts to normal sinus rhythm at 80 BPM.

To simulate cardiac output, use the cardiac-output adapter box, which is supplied as part

of the cardiac-output option. (See the section in the “Setting Up for a Cardiac-Output

Test” section later in this chapter.)

Setting Up For a Cardiac-Output Test

Action

1. Configure the cardiac-output monitor to the settings listed in Table 2-28, which are

compatible with the MPS450 simulation:

Table 2-28. Cardiac-Output Monitor Settings

Variable Setting

CATHETER TYPE / SIZE: Baxter Edwards, 93a-131-7f

CALIBRATION COEFFICIENT: 0.542 for 0 °C injectate; 0.595 for 24 °C injectate

INJECTATE VOLUME: 10 cc

INJECTATE TEMPERATURE: 0 °C or 24 °C

2. Connect the cardiac-output adapter box to the CO/TEMP connector on the right-side

panel of the MPS450.

3. Connect the BT thermistor cable from the cardiac-output monitor to the smaller 4-pin

connector on the cardiac-output adapter box. This is the blood-temperature-

simulation line directly wired to the MPS450.

4. Connect the injectate-temperature cable from the cardiac-output monitor to the bigger

4-pin switchcraft connector on the cardiac-output adapter box. This line is wired to

the trimpot on the front panel of the CO adapter box, enabling the resistance to be set

correctly to either 0 °C or 24 °C, as displayed on the CO monitor.

5. With the MPS450 turned on, the blood-temperature indicator on the CO monitor

should read approximately 37 °C.

6. Turn the trimpot on the CO adapter box until the injectate-temperature (IT) sensor

1 2 ... 63 64 65 66 67 68 69 70 71 72 73 ... 125 126

Comments to this Manuals

No comments

Fluke-biomedical MPS450 User Manual Page 68

Comments to this Manuals

Related products and manuals for Equipment Fluke-biomedical MPS450