GE CARESCAPE, Руководство пользователя

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Neuromuscular transmission
Post tetanic count (PTC) mode
When the response to the fourth TOF stimulation pulse disappears or the first twitch is
very weak, the TOF% is not available and only the counts can be observed.
When the stimulation pulses no longer give any stimulation response, the count also
disappears. To monitor the relaxation level, you can then start tetanic stimulation and
estimate the relaxation level from the post tetanic count, PTC. Tetanic stimulation
is a continuous stimulation of five seconds. After tetanic stimulation, single twitch
stimulations are generated. The number of detected responses is counted and
expressed as PTC. The fewer the responses, the deeper the relaxation.
If the responses do not fade away, a maximum of 20 responses are counted and the
measurement value is replaced by >20.
After tetanic stimulation, NMT measurement is stopped for one minute. After that, the
monitor automatically continues with the previously selected cycle.
Single twitch (ST) mode
In single twitch stimulation one pulse is generated and its response is measured.
NMT practicalities
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Normally, defasciculating doses of non-depolarizing neuromuscular blocking
agents (precurarisation) do not affect the supramaximal current nor the reference
value.
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Average lifetime of a MechanoSensor is two years, depending on the use. The
sensor has been validated to last 700,000 twitches.
Inappropriate function of the measurement is often caused by incorrect accessory
connection or misuse of the products. Therefore, note the following:
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Handle the sensor and cables carefully to maximize their lifetime.
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Piezosensor inside the MechanoSensor is very sensitive to shocks.
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Attach the MechanoSensor correctly.
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It is recommended to secure the MechanoSensor with a narrow tape. Wide
tape might prevent adequate movement of the sensor with the thumb during
the measurement.
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Check the quality of the stimulation electrodes.
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Use GE approved NMT electrodes for stimulation. They are tested with the
module and provide low impedance, which is crucial for accurate measurement.
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Do not use the electrodes after their expiration date.
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Perform a visual check of the MechanoSensor or ElectroSsensor and cable.
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Regular visual checking of the cable and sensor is recommended. If you see any
signs of broken cables or joints of the MechanoSensor, replace those parts.
NMT troubleshooting
Problem Solution
NMT reference search and measurement fail.
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Check the electrode quality and positioning.
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Replace stimulating electrodes.
Measurement is disturbed.
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Check the black ground electrode.
370 CARESCAPE Modular Monitors 2062971-001