Clinical scenario

A 30 year old man is brought to the emergency department with a Glasgow Coma Scale score of 8 after falling down stone steps while drunk. Although he has not vomited, you are concerned that he cannot protect his airway. You decide to do a rapid sequence induction. As you organise and check your equipment, you ask the nurse to bring the departmental capnograph to the bedside. She tells you that it is still in ITU where it was left after transferring the last intubated patient. She does, however, suggest you use a disposable colourimetric CO₂ detector found in the paediatric arrest trolley. You wonder whether you should wait five minutes while the capnograph is brought from ITU, or whether the colourimetric indicator will be just as accurate?

Three part question

In an [emergency intubation] is [a colourimetric carbon dioxide detector as reliable as capnography] at [verifying endotracheal tube placement]?

Search strategy

Medline 1966–02/03 using the OVID interface. [(exp Carbon Dioxide OR end-tidal.mp OR exp Capnography OR carbon dioxide.mp OR capnograph$.mp) AND (colorimetric.mp OR exp Colorimetry OR colourimetric.mp)] LIMIT to human AND English language.

Search outcome

Altogether 69 papers were found of which four were relevant to the question. Details of these papers are shown in table 3.

Comment(s)

There have been no studies investigating the use of these devices exclusively within the emergency department.

Clinical bottom line

The colourimetric CO₂ detector is as accurate as IR capnography at detecting tracheal intubation, but is potentially less accurate at detecting oesophageal intubation.