Respiratory Acidosis and Alkalosis
Activity 1: Normal Breathing
1.At 20 seconds, pH = 7.41
2.At 40 seconds, pH = 7.41
3.At 60 seconds, pH = 7.41
4.Did the pH level of the blood change at all during normal breathing? If so, how?No, not at all.
5.Was the pH level always within the “normal” range for the human body? yes
6.Did the PCO2 level change during the course of normal breathing? If so, how? No
Activity 2a: Hyperventilation – Run 1
1.At 20 seconds, pH = 7.68
2.At 40 seconds, pH = 7.68
3.At 60 seconds, pH = 7.68
4.Maximum pH = 7.68
5.Did the pH level of the blood change at all during this run? If so, how? Yes, it went extremely high then low.
6.Was the pH level always within the “normal” range for the human body? If not, when was the pH value outside of the normal range, and what acid/base imbalance did this pH value indicate? No, Alkalosis
7.Did the PCO2 level change during the course of this run? If so, how? Yes, the levels were as high as 40 and as low as 19.7
8.If you observed an acid/base imbalance during this run, how would you expect to renal system to compensate for this condition? By retaining more H+
This is correct below in Activity 3, here you want to retain H+, excrete HCO3-
9.How did the hyperventilation trace differ from the trace for the normal breathing? Did the tidal volumes change? The tidal volumes were different than those of normal. The waves were a lot larger than those of the normal breathing.
10.What might cause a person to hyperventilate? Anxiety
Activity 2b: Hyperventilation – Run 2
1.What happened to the trace after the 20-second mark when you stopped the hyperventilation? Did the breathing return to normal immediately? Explain your observation. The breathing did not return to normal immediately after returning to normal breathing. The pH level stayed the same for a few seconds before returning to the normal breathing patterns.
Activity 3: Rebreathing
1.At 20 seconds, pH = 7.41
2.At 40 seconds, pH = 7.41
3.At 60 seconds, pH = 7.24
4.Did the pH level of the blood change at all during this run? If so, how? Yes, the pH level increased as time passed.
5.Was the pH level always within the “normal” range for the human body? If not, when was the pH value outside of the normal range, and what acid/base imbalance did this pH value indicate? No, Acidosis
6.Did the PCO2 level change during the course of this run? If so, how? Yes, the levels varied between 40 and 53.02
7.If you observed an acid/base imbalance during this run, how would you expect the renal system to compensate for this condition? Excrete more H+
8.How did the rebreathing trace differ from the trace for normal breathing? Did the tidal volumes change? The tidal volumes became larger as the time passed.
9.Give examples of respiratory problems that would result in pH and PCO2 patterns similar to what you observed during rebreathing? Breathing into a bag
Renal System Compensation
Activity 4: Renal Response to Normal Acid/Base Balance
1.At normal PCO2 and pH levels, what level of H+ was present in the urine? Normal
2.What level of [HCO3-] was present in the urine? Normal
3.Why does the blood pH value change as PCO2 changes? Because the Pco2 has an effect on the pH.
4.How does the blood pH value change as Pco2 changes? The pH value either decreases or increases with the Pco2 value.
Activity 5: Renal Response to Respiratory Alkalosis
1.What level of [H+] was present in the urine at each of these PCO2/pH levels? Normal
2.What level of [HCO3-] was present in the urine at each of these PCO2/pH levels? Normal
3.Assuming that enough time has passed for the renal system to fully compensate for respiratory alkalosis, would you expect PCO2 levels to increase or decrease? Would you expect blood pH levels to increase or decrease?
4.Which type of breathing resulted in PCO2 levels closest to the ones we experimented with in this activity – normal breathing, hyperventilation, or rebreathing?
5.Explain why this type of breathing resulted in alkalosis. Too little carbon dioxide
Activity 6: Renal Response to Respiratory Acidosis
1.What level of [H+] was present in the urine at each of these PCO2/pH levels?Elevated
2.What level of [HCO3-] was present in the urine at each of these PCO2/pH levels?Decreased
3.Assuming that enough time has passed for the renal system to fully compensate for respiratory acidosis, would you expect PCO2 levels to increase or decrease? Would you expect blood pH levels to increase or decrease?
4.Which type of breathing resulted in PCO2 levels closest to the ones we experimented with in this activity – normal breathing, hyperventilation, or rebreathing?
5.Explain why this type of breathing resulted in acidosis. Too much CO2
Metabolic Acidosis and Alkalosis
Activity 7: Respiratory Response to Normal metabolism
1.What is the respiratory rate? 15
2.What is the blood pH? 7.4
3.Are the blood pH and PCO2 values within normal ranges? yes
Activity 8: Respiratory Response to Increased Metabolism
1.How did respiration change? Increased to 17
2.How did blood pH change? Decreased to 7.34
3.How did PCO2 change? Increased to 45
4.How did [H+] change? Increased to 47
5.How did [HCO3-] change? Decreased to 20
I did not understand the next 4 questions and how to answer them.
6.Explain why these changes took place as metabolic rate increased?
As the body’s metabolic rate decreased, less carbon dioxide was formed as a metabolic waste product. This caused a decrease in [H+] generation, which increased the plasma pH, causing respiration to decrease in order to retain more carbon dioxide in the blood and restore pH to a normal value. -1.5pts
7.Which metabolic rates caused pH levels to decrease to a condition of metabolic acidosis?
8.What were the pH values at each of these rates?
At metabolic rate = 30, the pH value was about 7.47. At metabolic rate = 20, the pH value was about 7.51. Alkalosis occurs at pH values above 7.45. (The pH values will vary slightly from run to run.) -1.5pt
9.By the time the respiratory system fully compensated for acidosis, how would you expect the pH values to change?
By the time the respiratory system fully compensated for alkalosis, you would expect pH levels to decrease to normal values. -1.5pts
Activity 9: Respiratory Response to Decreased Metabolism
1.How did respiration change? Decreased to 13
2.How did blood pH change? Increased to 7.43
3.How did PCO2 change? Decreased to 37
4.How did [H+] change? Decreased to 38
5.How did [HCO3-] change? Increased to 26
6.Explain why these changes took place as metabolic rate decreased?
7.Which metabolic rates caused pH levels to increase to a condition of metabolic alkalosis?
8.What were the pH values at each of these rates?
9.By the time the respiratory system fully compensated for alkalosis, how would you expect the pH values to change?
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