Ultrasonography for Diagnosis of Traumatic Pneumothorax Detection
October 2007
October 2007
Ultrasonography for the Diagnosis of Traumatic Pneumothorax Detection
Search Strategy: PUBMED search for pneumothorax combined with PUBMED search for ultrasound. Fifth “hit” is an article addressing the clinical question and Web of Science search performed to identify subsequent citations of this article. Using this search strategy 16 articles are identified with four selected for review:
A 35yr old male motorcyclist presents to you after EMS found him lying supine 50 feet from his bike. He appears clinically intoxicated and clearly altered. He is actively bleeding from a large scalp wound, and is vigorously fighting to remove his straps and c-collar, splashing blood at you and your team members despite your best efforts to verbally control him. You decide that intubation is necessary to control the situation and prevent further harm to him and your team. Using RSI you easily intubate him with direct visualization and confirm it using the usual techniques. Looking at his chest you note ecchymosis on both sides of his chest and extending to his right flank and abdomen. Breath sounds are equal and clear but you note crepitus on the right chest wall. Trachea is midline. You finish your primary survey. Vitals show pulse of 110 regular and BP 100/70. You look at the CXR which shows no rib fractures, infiltrates, or pneumothorax.
A whole-body CT will be required, however Radiology informs you that they are still doing a full body scan on the previous trauma and it will take another 10 minutes to finish. You suspect that clinically he has a pneumothorax but are uncertain which side. Being the astute clinician you remember that evidence has suggested supine CXR is poor at diagnosing pneumothorax (29-72% missed, J Trauma 2005;59:917) and also you recall hearing talk about the extended FAST scan that includes bilateral lung views. You wonder how ultrasound would compare to CXR or CT for diagnosing pneumothorax?
PICO Question
Population: ED patients with suspected pneumothorax (traumatic or spontaneous)
Intervention: EM physician ultrasound for pneumothorax diagnosis
Control: CT chest or CXR for pneumothorax diagnosis
Outcome: Diagnostic test characteristics (Likelihood Ratio), time-delay until identification of pneumothorax, delay-related morbidity
Years
Fourth years: Ultrasound Diagnosis of Pneumothorax. Radiol Med 2006; 111: 516-525. (http://pmid.us/ 16779538)
Articles
Article 1: Surgeon-Performed Ultrasound for Pneumothorax in the Trauma Suite J Trauma 2004; 56: 527-530
ANSWER KEY
Article 2: Rapid detection of pneumothorax by ultrasonography in patients with multiple trauma Critical Care 2006; 10: R112
ANSWER KEY
Article 3: A Prospective Comparison of Supine Chest Radiography and Bedside Ultrasound for the Diagnosis of Traumatic Pneumothorax, Acad Emerg Med 2005; 12: 844-849
ANSWER KEY
Article 4: Ultrasound Diagnosis of Pneumothorax, Radiol Med 2006; 111: 516-525
ANSWER KEY
Bottom Line
Highly trained (minimum 28-hours didactic and hands-on US instruction) EM physician or trauma surgeon-performed ultrasonography as an adjunct to FAST exam can detect blunt or penetrating pneumothorax before portable supine chest x-ray with impressive diagnostic test characteristics (LR+ > 30, LR- < 0.14). The current studies have limited external validity since motivated, experienced, highly trained EM/surgeon ultrasonographers performed the studies in single centers without uniform application of the Gold standard. Future studies using EM-providers with a wide range of US-experience from various ED settings (academic, rural non-academic, space, polar ice caps, etc.) should be done before this imaging modality is accepted as standard of care