Smart CapnoLine EtCO2 circuits are ideal for nonintubated applications such as monitoring ventilatory status in asthma, brochospasm, COPD, and procedural sedation-situations where oral ventilation can occur and cause inaccurate readings with nasal only lines. The "smart" design facilitates a crisp continuous waveform and accurate data for patients alternating between oral and nasal breathing. Smart CapnoLine monitors exhaled CO2 from oral and/or nasal ventilation.