ECG Cable and Pulse/Pulse Oximeter Setup
- Plug the red, black and green leads into the REACH color coded ports.
- Snap the leads onto the stickie electrodes, then place the stickie electrodes like this:
- The black lead goes under the right clavicle.
- The red lead goes on the lower left abdomen.
- The green (ground) lead goes on the lower right abdomen.
Make sure you snap the leads onto the stickie electrodes before putting them on yourself.
- Keep the REACH-DL flat on the table and rest your pointer or middle finger of your non-dominant hand on the pulse port. This is the hand you do not use all the time. Make sure your arm is flat on the table and your finger is relaxed.
- When you are ready to start recording data, just make sure the you relax and sit very still so there is no movement interference on the data.
The ECG and the Pulse Oxygen Saturation in a Resting Subject
Aim
To measure and correlate the oxygen saturation, heart rate, and the pulse latency in a resting individual.
Procedure
- While keeping your finger on the pulse port of the REACH-DL, use your other hand to click on the Record button.
NOTE – It can take 30 seconds or more for the O2 sensor to level out. If the reading is 80%, then the PulseOx has not registered. The reading should be in the 90s.
- Click on the AutoScale All button.
- Type "Resting ECG" in the Mark box and click the Mark button. This will make a black mark with text on your screen.
- Record for 5 minutes then click Stop.
- Click File ---> Save As, name the file "ECG-PO2", and save your data to your LabScribe Data folder on your Desktop.
Data Analysis
- Go to the beginning of your recording by clicking on the down arrow just to the right of the Mark Button and click the mark "Resting-ECG".
- Make sure to have at least 10 ECG cycles on screen. Double or half the display time by clicking the mountain icons once.
- Click the Analysis icon to bring you to the Analysis window.
- Move the cursors so they are on either side of all 10 ECG waves.
- Look at the names at the top of the ECG channel. The names of the functions used in the analysis are: T2-T1, Max, Min, and Mean. These are the values that you will be measuring.
- Record the following information from the O2 Saturation and the Heart Rate channels:
- Maximum Oxygen Saturation Level, which is the value for Max on the O2 Saturation channel.
- Minimum Oxygen Saturation Level, which is the value for Min on the O2 Saturation channel.
- Mean Oxygen Saturation Level, which is the value for Mean on the O2 Saturation channel.
- Maximum Heart Rate, which is the value for Max on the Heart Rate channel.
- Minimum Heart Rate, which is the value for Min on the Heart Rate channel.
- Mean Heart Rate, which is the value for Mean on the Heart Rate channel.
- Measure the Pulse Latency. This is the time interval between the peak of the R wave and the peak of the pulse wave that follows the R wave. Place one cursor on the peak of an R wave and the second cursor on the peak of the
pulse wave just to its right. The value for T2-T1 on any channel is the Pulse Latency.
- Measure this time for two additional ECG/Pulse cycles. Calculate the average Pulse Latency by adding these values together and then dividing by 3.
Click the "M" icon on the toolbar to get back to the Main recording screen.
Reset Your Display Time - In the display time box, type 10 and click enter. This will reset your display time to 10 seconds for Exercise 2.
Note - Write all your values on a data table so you can refer back to them when answering the questions.
You can open and close the Journal by clicking the "Notebook" icon.
The ECG and the Pulse Oxygen Saturation After Exercising
Aim
To measure the effects of exercise on blood oxygen saturation level, heart rate, and pulse latency.
Procedure
- After finishing Exercise 1, carefully unsnap the leads from the stickies. Leave the stickies on.
- Exercise for at least 10 minutes - do jumping jacks, go run around, or do some other form of exercise. You should have a very elevated heart rate and be breathing deeply when you are done.
- As soon as your are done exercising, sit down and resnap the leads onto the stickies, Place your thumb on the pulse/pulse oximeter port. Remember to use your non-dominant hand.
- Click Record. Click AutoScale. While recording, type "After Exercise" in the Mark box and click the Mark button.
- Continue recording until your heart rate has returned to normal or for 5 minutes, whichever comes first.
- Enter marks every 1 minute by typing "1", "2", "3", etc... in the Mark area and click the Mark button.
- Click Stop after 5 minutes even if the your heart rate has not returned to normal.
- Click Save to save your data.
Data Analysis
- Go to the beginning of your recording by clicking on the down arrow just to the right of the Mark Button and click the mark "After Exercise". This will bring you to right when you sat down after exercising.
- Make sure to have at least 10 ECG cycles on screen. Double or half the display time by clicking the mountain icons once.
- Move the cursors so they are on either side of all 10 ECG cycles.
- Record the following information from the O2 Saturation and the Heart Rate channels:
- Maximum Oxygen Saturation Level, which is the value for Max on the O2 Saturation channel.
- Minimum Oxygen Saturation Level, which is the value for Min on the O2 Saturation channel.
- Mean Oxygen Saturation Level, which is the value for Mean on the O2 Saturation channel.
- Maximum Heart Rate, which is the value for Max on the Heart Rate channel.
- Minimum Heart Rate, which is the value for Min on the Heart Rate channel.
- Mean Heart Rate, which is the value for Mean on the Heart Rate channel.
- Measure the Pulse Latency. This is the time interval between the peak of the R wave and the peak of the pulse wave that follows the R wave. Place one cursor on the peak of an R wave and the second cursor on the peak of the
pulse wave just to its right. The value for T2-T1 on any channel is the Pulse Latency.
- Measure this time for two additional ECG/Pulse cycles. Calculate the average Pulse Latency by adding these values together and then dividing by 3.
- Click the "M" icon on the toolbar to get back to the Main recording screen.
- Click the down arrow to the right of the Mark button and click "1" to bring you to the section of data 1 minute after sitting down. Then click the Analysis button to go back into the Analysis window.
- Repeat the data analysis for this section of data. Measure the same parameters as above. Click the “M” icon to get back to the Main window.
- Move through the sections of data by clicking the down arrow by the Mark button and choosing the next mark ("2", "3" etc…) and then go back into the Analysis window. Measure the same parameters for each 1 minute interval throughout the recovery period. Stop when your heart rate returned to normal and note down how long that took.
Note - Write all your values on a data table so you can refer back to them when answering the questions.
You can open and close the Journal by clicking the "Notebook" icon.
Answer the following:
Exercise 1
- What electrical and mechanical events take place during the R wave?
- What events take place in the cardiovascular system during the R and pulse waves?
- Does your oxygen saturation level remain constant throughout the ECG cycles?
- If the levels fluctuate during the ECG cycles, what could be a cause for this fluctuation?
- Is the heart rate consistent throughout the recordings? If there are changes in heart rate, what could be causing these changes?
Exercise 2
- How does your heart rate at rest and at 0, 1, 2, 3, and 4 (or more) minutes after exercise (recovery) compare? Is there any variation between the rates for each time period? Is there a trend and what is it?
- Does your oxygen saturation level remain constant throughout the ECG cycles after exercising? Does it change between 1 minute and 5 minutes after exercise?
- If the levels fluctuate during the ECG cycles after exercise, what could be a cause for this fluctuation?
- How does the heart rate change after exercise? Did you recover back to your resting heart rate? If so, how long did it take? If not, why do you think that is?
- Is there any effect on the blood flow through subject’s finger as the subject is exercising? How would you explain this? Does this affect the O2 concentration in the blood? Explain physiologically what is happening with the oxygen concentration in your blood.
- How does your body maintain blood oxygen concentration?
- Did you see a change in pulse latency between resting and each minute after exercise? What happened and why?