UMEM Educational Pearls

"PQRST" - Capnography in Cardiac Arrest

  • Resuscitation of the patient in cardiac arrest can be stressful, chaotic, and variable depending on the setting.
  • Capnography is a valuable tool in the management of patients in cardiac arrest.
  • Heradstveit, et al. published a pneumonic for the use of capnography during cardiac arrest:
    • P - Position of the tube
      • The sensivity and specificity of capnography for endotracheal tube confirmation is superior to auscultation and capnometry.
    • Q - Quality of CPR
      • Early detection of poor-quality compressions.
    • R - ROSC
      • A sudden increase in end-tidal CO2 can indicate ROSC without interrupting CPR for pulse checks.
    • S - Strategy
      • May assist clinicians in determining underlying etiology of cardiac arrest.
    • T - Termination
      • An end-tidal CO2 value < 10 mm Hg after 20 min of resuscitation has been shown to be very accurate in predicting death.


Heradstveit BE, Heltne JK. PQRST - A unique aide-memoire for capnography interpretation during cardiac arrest. Resuscitation 2014; 85:1619-20.