Title 1615_21Mar25_Piper A_Transcutaneous carbon dioxide monitoring.pdf ✅

Transcutaneous carbon dioxide monitoring: How, when and why Amanda Piper, PhD Clinical Lead, Respiratory Support Service Royal Prince Alfred Hospital Camperdown 1

• PCO2 (or surrogate) >55mmHg for >10mins or • ↑PCO2 (or surrogate) >10mmHg from awake supine value to >50mmHg for 10mins AASM, J Clin Sleep Med 2012 Defining hypoventilation during sleep Surrogates: End-tidal CO2 or Transcutaneous CO2 Continuous monitoring permits identification of isolated rises (REM/position/obstruction) 3
ETCO2 Altered by mouth breathing & leak Poorer correlation with ABG Not valid in COPD, small lung volumes, obesity etc TcCO2 Good correlation with ABGs Requires time to equilibrate Altered by skin abnormalities & perfusion Time lag to reflect change CO2 Piper, Sleep Med Clin 2014 Sleep: non-invasive CO2 monitoring ADVANTAGES OVER ABGS Non-invasive & painless Continuous Easy to apply Does not wake the patient 4