Acoustic reflectometry and endotracheal intubation

David M. Eckmann*, Raymond Glassenberg, Noam Gavriely

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

33 Scopus citations


To determine whether acoustic reflection measurement of the upper airway can be used to identify tracheas that are difficult to intubate, we conducted a pilot study of adults with a documented history of unexpected failed endotracheal intubation (16 cases) and compared them with 16 controls with previous successful intubation. The two groups were matched by age, sex, height, and weight. Acoustic reflection measurements of airway cross sectional area versus distance were made at six combinations of body (upright and supine) and neck (flexed, neutral, and extended) positions. Cumulative airway volumes were calculated from the incisors to the glottis, and these were subdivided into oral and pharyngeal volumes. For supine position with the neck extended, all patients who had been successfully intubated had pharyngeal volumes more than 43.4 mL (mean ± SD, 56.9 ± 8.3 mL), whereas pharyngeal volumes were less than 37.5 mL in all patients who had a history of unexpected failed intubation (mean ± SD, 19.7 ± 10.2 mL; P < 0.05). Using a cutoff of 40.2 mL, acoustic reflection enabled us to distinguish between patients with previous unexpected failed endotracheal intubation and those with previous successful intubation.

Original languageEnglish (US)
Pages (from-to)1084-1089
Number of pages6
JournalAnesthesia and analgesia
Issue number5
StatePublished - 1996

ASJC Scopus subject areas

  • Anesthesiology and Pain Medicine


Dive into the research topics of 'Acoustic reflectometry and endotracheal intubation'. Together they form a unique fingerprint.

Cite this