Test Indications Pulse oximetry Respiratory distress, failure Capnography ABG, VBG Comments Measures oxygen saturation Relative contraindication if agitation will worsen distress Not reliable if severe anemia No information about ventilation Respiratory distress, Measures end-tidal failure CO2 , CO2 Confirm, monitor waveform endotracheal tube Can be used in placement, ventilatory intubated or failure nonintubated Diagnose, differentiate patients upper and lower Approximates ABG airway obstruction, Paco2 if monitor therapeutic cardiovascular interventions status intact; Etco2 Monitor ventilation values 2–5 mm Hg during sedation