Pt has respiratory acidosis (low blood pH) due to his asthma exacerbation. What will the nurse expect to see?
Explanation & Rationale
Choice A reason: Respiratory acidosis does not cause no change in affinity of hemoglobin with oxygen. It causes a decrease in affinity of hemoglobin with oxygen, which means that hemoglobin releases more oxygen to the tissues. This is known as the Bohr effect, which is a physiological response to low pH and high CO2 levels. Choice B reason: Respiratory acidosis causes a decrease in affinity of hemoglobin with oxygen, which means that hemoglobin releases more oxygen to the tissues. This is the correct statement that describes the expected finding in this patient. The decrease in affinity of hemoglobin with oxygen is a compensatory mechanism that tries to restore the oxygen balance in the body. Choice C reason: Respiratory acidosis does not cause an increase in affinity of hemoglobin with oxygen. It causes a decrease in affinity of hemoglobin with oxygen, which means that hemoglobin releases more oxygen to the tissues. An increase in affinity of hemoglobin with oxygen would mean that hemoglobin holds on to oxygen more tightly, which would worsen the hypoxia in the patient. Choice D reason: Respiratory acidosis does not cause a decrease in blood CO2. It causes an increase in blood CO2, which is the primary cause of the low pH. A decrease in blood CO2 would indicate respiratory alkalosis, which is a condition of high pH and low CO2 levels.