Lung ultrasound for pneumothorax: literature for practice & simulation

Here’s a few articles on lung ultrasound. This post is a result of discussions as ARHT has recently added portable ultrasound as a new tool on the helicopters. This should be particularly useful in the assessment of pneumothorax! One study showed that rotor rotation doesn’t really affect image acquisition in M-mode – very cool!

In the trauma or pre-hospital setting, if you’re using ultrasound you want to be able to slap it on quickly and rule out that pneumo. Where to scan on the chest however hasn’t been well delineated and different institutions use different protocols. This study shows that we might need to scan lower down than we usually do. It may not change management but could be helpful to know your patient has a pneumo if they suddenly deteriorate in the trauma bay or in flight for those transporting patients. The authors suggest, based on CT scan analysis, that >80% of pneumothoraces will be detected by scanning between the 5th & 8th intercostals parasternally and 7-8th intercostal lateral to mid-clavicular line. Equates to regions 9, 11 and 12 on the image below. Much higher than the frequency of pneumothorax over the traditional regions scanned (regions 3 and 6 or the 2nd – 4th intercostals). This will definitely be useful for those in the pre-hospital setting who want to make a decision regarding flight as it may change with a patient who has a pneumothorax.

Regions 9, 11 and 12 based on CT scan analysis have higher frequencies of pneumothorax compared to regions 3 & 6. Image from Am J Emerg Med. 2012 Sep;30(7):1025-31

Finally, as we strive to make simulation accessible, this article outlines a slick way of simulating lung ultrasound at a very low cost! This is extremely useful if you’re running a sim scenario and don’t have access to pre-generated images or you forgot to bring them! The authors describe performing an ultrasound on the palm of the hand. To recreate the lung slide, you move the dorsum of the hand while scanning on the palm – they show some images how this worked using M-mode. Great idea and look forward to using it!