In order to minimize interruptions in compressions due to pulse checks, continuous end tidal CO2 (ETCO2) monitoring during compressions is recommended. Before spontaneous circulation returns, the ETCO2 is likely to be on the order of < 10 mmg Hg. At the moment spontaneous circulation returns, the ETCO2 is expected to abruptly increase to at least 35-40 mm Hg. Be wary, though, that the administration of sodium bicarbonate may transiently increase the ETCO2 even in the absence of return of spontaneous circulation (ROSC).
Use of ETCO2 in this manner allows one to assess the patient for ROSC without ever having to stop compressions for pulse checks.
