心电图教程8

• Belt tension may need adjustment (biomed dept) • Leakage current checked (biomed dept) • Unplug treadmill when moving it (do not place hands
beneath the treadmill when it is plugged in
display does not change
• Press on/standby key (shuts down after a possible delay of up to 5 seconds • Press on/standby again to restart
• Waveforms are flat for all leads on tracing
department or manufacturer’s technical support
Holter - Calibration
• No calibration is required for the monitor or
the analysis system • Holter monitor places calibration signals at the start of each recording automatically
Treadmill - Operation
Guidelines for Safe Operation
• Keep treadmill area clear (maintain open space at each side of at least 0.5 m and 2 m at the back) • Do not start treadmill with someone standing on the belt • Do not leave patient unattended on the treadmill • Secure loose clothing (check shoelaces) before starting treadmill • Keep speed and grade at minimum settings when patient gets on the treadmill • Patient should hold the handrail as the treadmill slows down. • Technologist must be in a position to support and assist the patient when the belt stops • Use the emergency stop button only for emergencies
Treadmill - Troubleshooting
• If the belt does not run, check the
Holter - Maintenance
• Cleaning: • Dampen a soft cloth with mild detergent and water • Clean recorder, lead wires, and belt clip • Do not leave batteries in the recorder
• Low battery
• Inspect battery compartment, clean contacts if necessary • Install a new alkaline battery
• Battery does not last 24 or 48 hours
• Ensure a new alkaline battery is being used
ECG – Troubleshooting
• Unit will not turn on
• Unit not connected to AC line voltage • Battery has no charge • Faulty power cord or AC outlet
• Unit has frozen – will not respond to key strokes and
• Noise artifacts on ECG signal
• Ensure all electrodes are securely attached to the patient • Replace the patient cable
• If problems persist, contact facility biomedical
• • • • Pat Poor electrode contact with skin If problem persists, try changing filter setting to 40 Hz – manufacturer warns that this may affect the ECG output
ECG - Maintenance
• Computerized units perform a self-test self-
every time they are powered up
• No calibration is necessary
• Visually inspect patient cable for cracks
• Baseline drift for one or more leads
• Poor patient prep • Use of dissimilar electrodes or electrodes not recommended for ECG unit used • Electrodes need to sit longer on skin • Poor electrode contact with skin
when it is not in use
• Damage from corrosion could result
Holter Monitor – Troubleshooting
• No display
• Ensure patient cable is connected • Ensure battery is inserted with correct polarity • Install a new alkaline battery
ECG Troubleshooting
• Incorrect HR printed or displayed: • Bigeminal rhythm • Poor data quality (artifact) • QRS amplitude and T wave amplitude almost the same • Incorrect or missing measurement on printout • Poor data quality (artifact) • Rapid, large and erratic deflections • Broken lead wire
• The button will cut power to the belt drive motor • The button will lock into place • Turn counter-clockwise to unlock it counter-
Treadmill - Maintenance
HLT0073 Cardiac Diagnostics Instrumentation
Class 8
Instructor: Joanne Lambley, MSc (Kin)
Agenda
Discuss: • Electrocardiograph • Holter monitor • Treadmill • Exercise Testing System In terms of: • Maintenance • Troubleshooting • Calibration
• Electrodes not applied properly • ECG acquired too quickly (wait for ‘sensors OK’) • Patient cable not attached properly to unit or is faulty
ECG - Troubleshooting
• Inspect treadmill belt for wear • Check position of belt
• Should not rub against the frame • Should be centered
• Cleaning:
• • • • • Turn off treadmill and unplug Clean exterior and belt with damp sponge Do not use detergents or cleaning agents on deck Do not let liquids enter the interior of the treadmill Once per week, elevate treadmill to maximum grade and clean floor underneath (excess dust may interfere with operation)
and broken or bent pins • Test with a simulator
• Check the signal transmission through the cable by flexing the cable and electrode lead wires and observing the ECG rhythm for irregular tracings