During procedural sedation, which of the following is an early sign of respiratory compromise?

During procedural sedation, which of the following is an early sign of respiratory compromise?

• A. Rising end-tidal CO2
• B. Normal respiratory rate
• C. Decreased work of breathing
• D. Decreasing oxygen saturation

Answer: (C)

In procedural sedation, monitoring ventilation with capnography is essential because end-tidal CO2 reflects how well a patient is ventilating. An early sign of respiratory compromise is a rising end-tidal CO2, which shows CO2 is not being cleared adequately and ventilation is becoming inadequate—even before oxygen levels fall. A normal respiratory rate can still hide hypoventilation if breaths are shallow or ineffective, so rate alone isn’t reliable. Decreased work of breathing would suggest the opposite—less effort, not more need for intervention. Decreasing oxygen saturation tends to occur later, after ventilation has already declined. So, an upward trend in end-tidal CO2 is the earliest warning and should prompt prompt assessment and potential intervention.

In procedural sedation, monitoring ventilation with capnography is essential because end-tidal CO2 reflects how well a patient is ventilating. An early sign of respiratory compromise is a rising end-tidal CO2, which shows CO2 is not being cleared adequately and ventilation is becoming inadequate—even before oxygen levels fall. A normal respiratory rate can still hide hypoventilation if breaths are shallow or ineffective, so rate alone isn’t reliable. Decreased work of breathing would suggest the opposite—less effort, not more need for intervention. Decreasing oxygen saturation tends to occur later, after ventilation has already declined. So, an upward trend in end-tidal CO2 is the earliest warning and should prompt prompt assessment and potential intervention.