Question

A febrile patient is receiving non-invasive positive pressure ventilation with an IPAP of 26 and an EPAP of 10 cmH2O. The following uncorrected blood gas data on these settings is available:

pH 7.32 PaCO2 48 mm Hg PaO2 80 mm Hg HCO3- 24 mEq/L BE 0 mEq/L Which of the following change is most appropriate?
A. maintain settings
B. increase IPAP
C. decrease EPAP
D. increase IPAP and EPAP

Answer 1

The patient with slight acidosis should have an increased IPAP to enhance ventilation and CO2 removal, correcting the acidosis. The correct answer is to increase IPAP, not EPAP or both IPAP and EPAP. This approach aims to bring the patient's pH back into the normal range. Option B is correct.

Step-by-step explanation:

The febrile patient's uncorrected blood gas data indicates a pH of 7.32, which is slightly lower than the normal range of pH (7.35-7.45), a PaCO2 of 48 mm Hg, which is at the upper limit of the normal range (male: 35-48 mm Hg, female: 32-45 mm Hg), and a PaO2 of 80 mm Hg, which is within normal oxygen levels for arterial blood. The bicarbonate, HCO3-, at 24 mEq/L is within the normal range, and the BE (Base Excess) of 0 mEq/L indicates that there is no significant metabolic compensation occurring.

Given this information, the most appropriate change to address the slight acidosis (as indicated by the low pH) and fully normalised PaCO2 would be to increase the IPAP (Inspiratory Positive Airway Pressure). This would enhance the ventilation, hence increasing CO2 removal and raising the pH towards the normal range. Therefore, the best answer would be option B: increase IPAP.

Changing the EPAP (Expiratory Positive Airway Pressure) is not primarily indicated in this scenario as the focus is on adjusting the carbon dioxide removal, which is more directly impacted by the IPAP setting.