A male patient presents to the emergency department. The arterial blood gas report is as follows: pH, 7.2; pCO2, 81 mmHg; and HCO3, 40meq/L. which of the following is the most likely diagnosis?
To solve the given problem, we must analyze the arterial blood gas (ABG) values to determine the most likely diagnosis. We are provided the following values:
pH: 7.2
pCO2: 81 mmHg
HCO3-: 40 meq/L
Let's evaluate these:
Normal physiological values: The normal pH range is 7.35 to 7.45. The normal pCO2 range is 35 to 45 mmHg. The normal HCO3- range is 22 to 26 meq/L.
In this case, the pH is 7.2, which indicates acidosis (since it is below the normal range of 7.35-7.45).
The pCO2 is elevated at 81 mmHg, suggesting a retention of CO2, which is typical of respiratory acidosis.
The HCO3- is elevated at 40 meq/L, suggesting renal compensation by increasing bicarbonate to attempt to normalize the pH.
Conclusion: The primary issue is an elevated pCO2, leading to an acidic pH, indicative of respiratory acidosis. This also matches the elevated HCO3- value, indicating compensation. Hence, the most likely diagnosis is respiratory acidosis, making this the correct choice for the given arterial blood gas values.