Clinical tests for confirming tracheal intubation or excluding oesophageal intubation: a diagnostic test accuracy systematic review and meta‐analysis

Abstract

Unrecognised oesophageal intubation causes preventable serious harm to patients undergoing tracheal intubation. When capnography is unavailable or doubted, clinicians still use clinical findings to confirm tracheal intubation, or exclude oesophageal intubation, and false reassurance from clinical examination is a recurring theme in fatal cases of unrecognised oesophageal intubation. We conducted a systematic review and metaanalysis of the diagnostic accuracy of five clinical examination tests and the oesophageal detector device when used to confirm tracheal intubation. We searched four databases for studies reporting index clinical tests against a reference standard, from inception to 28 February 2023. We included 49 studies involving 10,654 participants. Methodological quality was overall moderate to high. We looked at misting (three studies, 115 participants); lung auscultation (three studies, 217 participants); combined lung and epigastric auscultation (four studies, 506 participants); the oesophageal detector device (25 studies, 3024 participants); `hang-up´(two non-human studies); and chest rise (one non-human study). The reference standards used were capnography (22 studies); direct vision (10 studies); and bronchoscopy (three studies). When used to confirm tracheal intubation, misting has a false positive rate (95%CI) of 0.69 (0.43-0.87); lung auscultation 0.14 (0.08-0.23); fivepoint auscultation 0.18 (0.08-0.36); and the oesophageal detector device 0.05 (0.02-0.09). Tests to exclude events that invariably lead to severe damage or death must have a negligible false positive rate. Misting or auscultation have too high a false positive rate to reliably exclude oesophageal intubation and there is insufficient evidence to support the use of `hang-up´or chest rise. The oesophageal detector device may be considered where other more reliable means are not available, though waveform capnography remains the reference standard for confirmation of tracheal intubation.

Ten Steps Toward Improving In-Hospital Cardiac Arrest Quality of Care and Outcomes

“…An end-tidal carbon dioxide waveform capnography device should be used to confirm and monitor tracheal tube placement, 82 as classic clinical signs of tracheal intubation are not reliable. 83 Inject intravenous epinephrine (adrenaline) as quickly as possible for IHCAs with a nonshockable rhythm (and ideally within the first 5 minutes) 73 and after the second or third defibrillation for IHCAs with a shockable rhythm. 84 Repeat epinephrine at 3-to 5-minute intervals.…”

Capnography—An Essential Monitor, Everywhere: A Narrative Review

“…38,39 Historically used clinical signs (such as chest movement, auscultation, and tracheal tube [TT] condensation) have an unacceptably high false-positive rate. 40 If EI occurs and is not corrected quickly, it is associated with a high risk of severe hypoxemia and brain damage, pulmonary aspiration, cardiac arrest, and death. 26,31 Based on the British data from the Fourth National Audit Project (NAP4), EI causing severe harm occurred in approximately 1 in 1000,000 tracheal intubations in the OR, 1 in 15,000 in the ICU, and 1 in 10,000 in the ED.…”

The Theatre Recovery and Anaesthetic nurse Capnography Education (TRACE) project*

“…Misinterpretation of capnography and reliance on clinical signs to confirm correct tube position are themes common to all cases [1,4].…”