Hypocapnia

No ETCO2

No ETCO2

* Oesophageal intubation
* Accidental extubation
* Disconnection
* Equipment failure ­ has the machine and monitor been checked prior to induction?
* Cardiac arrest

Low ETCO2

Low ETCO2

* Airway
* Circuit
* Ventilation
* Gas exchange
* Decreased production

Airway

Airway

* Oesophageal intubation
* Accidental extubation

Circuit

Circuit

* Air entrainment (leak)
* Dilution with circuit gases (sampling problem)

Ventilation

Ventilation

* Ventilation settings
* Overenthusiastic hand ventilation
* Metabolic acidosis ­ spontaneously ventilating patient

Gas Exchange

Gas Exchange

* Pulmonary embolism
Air
Clot
Fat
Other
* Decreased cardiac output/arrest
* Severe hypotension

Decreased Production

Decreased Production

* Hypothermia
* Hypothyroidism
* Decreased Metabolism