A 58-year-old man returns from theatre following an emergency splenectomy after a motorcycle accident. A secondary trauma survey reveals that he has suffered left sided rib fractures and a right compound tibial fracture. On admission to the intensive care unit, he is sedated, intubated and ventilated, hypotensive (80/40 mmHg), has a tachycardia (140 beats per minute) and is cool peripherally.
a) List the likely causes of this man's shock state.
b) List the clinical features that would help distinguish between these likely causes.
c) What echocardiographic features are associated with the causes you have described?
a) List the likely causes of this man's shock state.
b) List the clinical features that would help distinguish between these likely causes
c) What echocardiographic features are associated with the causes you have described?
This is a question about the different causes of shock in trauma, and their relevant features, with a focus on the early use of ultrasound.
Questions a) and b) clearly favour the candidate who has recently done the EMST and is familiar with the ATLS manual, which is the best source for this sort of thing. I made my own summaries when I did that course.
Because questions a) and b) are rather straightforward, I will focus more on the echocardiographic investigation of shock in trauma.
A certain James Lai (FRCA, FANZCA) has published a brilliant set of slides for public delectation, which does this topic justice.
A 2011 study has also demonstrated that fluid assessment can be carried out quickly and effectively using IVC diameter and IVC respiratory variation, although in this study a surgical intensivist or an ultrasonographer (rather than an ED registrar) were performing the study. To address this concern, the same group later demonstrated that even a shaved ape could be trained to perform a limited goal-directed TTE.
Interestingly, there are also many studies of transoesophageal echo in trauma. One is tempted to salute the bravery of the man who would jam a TOE probe down into a trauma patient. However, it certainly seems to be helpful. A study comparing transthoracic and trasoesophageal assessment has demonstrated that TOE is significantly more accurate, and that TTE in severe chest trauma usually gives unsatisfactory images.
Ferrada, Paula, et al. "Transthoracic focused rapid echocardiographic examination: real-time evaluation of fluid status in critically ill trauma patients."Journal of Trauma and Acute Care Surgery 70.1 (2011): 56-64.
Ferrada, Paula, et al. "Limited transthoracic echocardiogram: so easy any trauma attending can do it." Journal of Trauma and Acute Care Surgery 71.5 (2011): 1327-1332.
Chirillo, Fabio, et al. "Usefulness of transthoracic and transoesophageal echocardiography in recognition and management of cardiovascular injuries after blunt chest trauma." Heart 75.3 (1996): 301-306.