Jerome Chee Yung Wong MD, Presenter: Nothing to Disclose

Fern Karlicki MD, Abstract Co-Author: Nothing to Disclose

Chris Christodoulou MD, Abstract Co-Author: Nothing to Disclose

Ross Brown MD, Abstract Co-Author: Nothing to Disclose

One of the leading causes of malpractice in anesthesia is unrecognized esophageal intubation, which can result in significant morbidity such as brain damage, pulmonary aspiration and even death. Sonographic assessment of endotracheal tubes in the cervical esophagus offers a non-invasive real-time approach in assessing tube positioning . To date, there are no studies demonstrating endotracheal tubes in the esophagus of anesthetized or comatose patients. There are also limited studies in determining how frequent the cervical esophagus can be seen with ultrasound. We performed a prospective sonographic study to determine the sensitivity of detecting the cervical esophagus. In addition we undertook a prospective study looking to determine the sensitivity and appearance of a nasogastric tube in the cervical esophagus.

Ninety three adult patients were recruited in a randomized fashion and a linear array probe was used to search for the cervical esophagus using the thyroid glands as a window. Twelve adult patients with an indwelling nasogastric tube (Med-Rx™, 14 or 16F) were recruited in a randomized fashion and the cervical esophagus was scanned with a linear array probe from the anterolateral aspect of the neck. This study is ongoing and a sample size of fifty patients will be achieved prior to the RSNA conference.

The cervical esophagus is successfully visualized in 93% of patients in the transverse and longitudinal planes. The nasogastric tube in the esophagus has a characteristic echogenic “double wall” signature corresponding to the outer and inner walls. It was detected in 92% and 58% in the parasagittal plane and transverse plane respectively. The long reflective surface in the parasagittal plane as opposed to the transverse plane allows easy and accurate identification.

Ultrasound is a convenient, fast, and effective method in detecting the cervical esophagus. It is a highly sensitive tool for detecting nasogastric tubes in the cervical esophagus. Considering that an endotracheal tube is larger than a nasogastric tube, sonographic imaging of the esophagus could potentially be used to rapidly identify accident esophageal intubation.

Wong, J, Karlicki, F, Christodoulou, C, Brown, R, Sonographic Detection of the Cervical Esophagus and Nasogastric Tube in the Esophagus.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4407007.html