From Surgical Critical Care Services (Ms Dixon and Drs Johnson and Shah) and Burn and Trauma Services (Dr Johnson), MedStar Washington Hospital Center, Washington, DC.
CORRESPONDENCE TO: Nimesh S. Shah, MD, Surgical Critical Care Services, MedStar Washington Hospital Center, 110 Irving St, NW, Washington, DC 20010; e-mail: Nimesh.Shah@medstar.net
Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.
A middle-aged man with 36 h of vertigo, nausea, and vomiting arrived at an outside hospital for evaluation. His medical history was notable for squamous cell carcinoma of the tongue and esophagus treated with chemotherapy, radiation, and surgical resection 7 years prior. His workup revealed a right-sided cerebellar mass with surrounding edema and mass effect. The patient was transferred to our institution for neurosurgical intervention. Preoperatively, his nausea and vomiting were recalcitrant to therapy with corticosteroids and hyperosmolar therapy. The remainder of his preoperative evaluation was unexceptional, including normal chest imaging and hemodynamic and respiratory parameters on ambient air.
Suboccipital craniectomy with metastatic mass resection was performed without complication, but the patient continued to have intermittent nausea and vomiting. Two days later, gradual hypoxia developed, necessitating a 50% Venturi mask to maintain oxygen saturation > 95%. He was without fever, and his WBC count was 15.3 × 103/μL. Chest radiography revealed a new radioopaque density in the right-side hemithorax (Fig 1).
On the same evening, the intensivists evaluated the patient for increasing tachypnea and hypoxia. The patient exhibited moderately labored breathing but was conversant and had an oxygen saturation of 94% on nonrebreather mask. The emesis basin was filled with clear, nonbloody vomit. His respiration was 25/min with decreased breath sounds on auscultation of the right-side lung base. The patient’s heart rate was 118/min with strong pulses in the extremities, and he was warm to the touch. A bedside ultrasound was performed to investigate the etiology of the patient’s hypoxia (Videos 1, 2).
Bedside Ultrasound 1
Bedside Ultrasound 2
On the basis of the images in Video 3 and the patient’s clinical history, it was determined that the opacity was in fact a distended gastric pull-through from the patient’s previous cancer surgery. A nasogastric tube was placed to decompress the stomach. After approximately 12 h and > 1,800 mL gastric output, the patient was able to be weaned from the nonrebreather mask to a 4-L nasal cannula. His respiratory status continued to improve, and he was discharged home on postoperative day 10.
In Videos 1 and 2, pleural ultrasound of the right-side chest reveals a large posteriorly located hypoechoic structure. The image, illustrating the curtain sign, is intermittently obscured by the lung proximally passing in and out with the patient’s respiratory efforts. The lung has comet tail shadows known as B lines, which are ultrasonic artifacts that represent thickening of the interlobular septa and originate from the pleural surface.1 Close examination demonstrates the echo-free space bounded by the diaphragm inferiorly and the lung proximally but not the chest wall, which is atypical of free-flowing pleural effusions. Additionally, a hyperechoic structure is visualized within the echo-free space without dynamic patterns characteristic of pleural effusions. The contrast agent seen entering the echo-free space in Video 3 confirmed that the hypoechoic structure was a distended stomach filled with gastric contents within the chest. The occasional ray-like B lines seen at the lung bases normally are more confluent in this image and likely represented pneumonitis from microaspiration.
Free-flowing pleural effusions take a gravitationally dependent position and are typically echo-free spaces. This space must be bounded by three anatomic landmarks: chest wall, diaphragm, and lung. Dynamic signs of pleural effusion may be visualized as lung flapping in the fluid. Other signs often found in inflammatory effusions are debris floating in the fluid (plankton sign) and echogenic strands moving with cardiac or respiratory motions2 (Discussion Videos 4, 5). The dynamic, but specific sinusoid sign is obtained by applying M mode on free-flowing pleural effusions. A hyperechoic line resembling a sine wave represents the visceral pleura moving proximally toward the inner chest wall during inspiration1 (Fig 2).
Although literature exists on the use of oral contrast agents for GI tract diagnostics, a basic understanding of ultrasound principles is all that is necessary in the acute setting. The interface between fluid and air nearly reflects 100% of ultrasound waves, making it ideally suited for contrast.3 A primarily water-based solution with bubbles can be introduced into the GI tract for ultrasound identification of structures.4 Here, ginger ale was the most readily available.
1. Ultrasound of the chest is better than chest radiograph to elucidate pleural pathology.
2. Free-flowing pleural effusions are hypoechoic structures bounded by lung, chest wall, and diaphragm. They are accompanied by dynamic signs, such as lung flapping, plankton sign, and sinusoid sign; lack of these characteristics should prompt consideration of alternate diagnoses.
3. GI structures can be identified with the instillation of oral contrast (carbonated fluid).
Financial/nonfinancial disclosures: The authors have reported to CHEST that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.
Other contributions:CHEST worked with the authors to ensure that the Journal policies on patient consent to report information were met.
Additional information: To analyze this case with the videos, see the online version of this article.
Become a CHEST member and receive a FREE subscription as a benefit of membership.
Individuals can purchase this article on ScienceDirect.
Individuals can purchase a subscription to the journal.
Individuals can purchase a subscription to the journal or buy individual articles.
Learn more about membership or Purchase a Full Subscription.
Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.
Some tools below are only available to our subscribers or users with an online account.
Download citation file:
Web of Science® Times Cited:
Customize your page view by dragging & repositioning the boxes below.
Enter your username and email address. We'll send you a reminder to the email address on record.
Athens and Shibboleth are access management services that provide single sign-on to protected resources. They replace the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Athens or Shibboleth authentication, please contact your site administrator to receive your user name and password.