Ultrasound can be used to reveal accumulation of secretions in the subglottic space of intubated patients. (A), which was produced using a 6- to 13-MHz linear array ultrasound probe (SonoSite, USA) and a long-axis lateral approach with the head rotated 20 to 30° to the opposite side,1 shows a sonolucent area that appeared after injecting 3 ml of saline through a subglottic catheter above the endotracheal tube (ETT) cuff, which had been insufflated with air. The sonolucent area disappeared after the injected saline had been suctioned out (B). Dynamic changes in sonolucency during injection followed by aspiration of saline via a subglottic catheter are shown (Supplemental Digital Content 1, http://links.lww.com/ALN/C472). Aspirating and reinjecting saline into the subglottic space of another intubated patient with supracuff secretions also revealed these phenomena (Supplemental Digital Content 2, http://links.lww.com/ALN/C473). In addition to the sonolucent area, a comet-tail artifact caused by bubble-rich secretions can also be seen in the ultrasound images (Supplemental Digital Content 2, http://links.lww.com/ALN/C473). This artifact resembles B-lines, which are specific to subpleural interstitial edema.2 Ultrasound seems to be a reliable technique for identifying secretions in the subglottic space and assessing the effectiveness of suctioning such secretions from an intubated patient in an operating room or intensive care unit setting. Given that suctioning subglottic secretions reduces the incidence of ventilator-associated pneumonia,3 we believe that ultrasound is a useful tool for airway care in an intubated patient. Whether it is as effective as existing techniques for minimizing ventilator-associated pneumonia remains to be determined by systematic studies.
The authors thank Dr. Trish Reynolds, M.B.B.S., F.R.A.C.P., Liwen Bianji, Edanz Group, Beijing, China, for editing the English text of a draft of this article.
The authors declare no competing interests.