During respiratory distress, carboxyhemoglobin monitoring may be performed under what condition?

• A. Only in ambulance
• B. For hyperthermia only
• C. PRN, if available
• D. Not used in BLS

Answer: (C)

Carboxyhemoglobin monitoring is an optional test used when carbon monoxide exposure might be a factor in respiratory distress. If the monitor includes a CO-oximeter, perform this measurement as needed—PRN—when there is suspicion and the device capability exists. It isn’t required in every case and isn’t universally available on all EMS setups. This is why the correct approach is to use it if available and deemed helpful.