From the Research
Corticosteroids can increase serum CO2 levels in some patients, particularly those with underlying respiratory conditions or kidney disease, due to their metabolic effects and potential to worsen conditions like COPD. The mechanism involves corticosteroids' metabolic effects, which can lead to increased bicarbonate retention by the kidneys and metabolic alkalosis, as well as fluid retention and muscle weakness, potentially causing respiratory compromise and CO2 retention 1. This effect is dose-dependent, with higher doses (such as prednisone >20mg daily) more likely to cause significant changes. Key points to consider include:
- The impact of corticosteroids on CO2 levels is usually reversible when steroid doses are reduced or discontinued, though this should always be done gradually under medical supervision to prevent adrenal crisis.
- Patients on high-dose steroid therapy should have their electrolytes and CO2 levels monitored regularly.
- The use of corticosteroids in patients with acute respiratory distress syndrome (ARDS) has been shown to reduce all-cause mortality and the duration of mechanical ventilation, and increase the number of ventilator-free days, but may also increase the risk of hyperglycemia 1.
- The certainty of evidence for the use of corticosteroids in ARDS is moderate to low, and caution is recommended in the actual clinical application of these results. Overall, the decision to use corticosteroids should be made on a case-by-case basis, taking into account the potential benefits and risks, and monitoring patients closely for any adverse effects.