L33: Life Saving Impact of ER and Trauma Radiology Flashcards
What is emergency radiology?
medical imaging (x-ray, ultrasound, MRI, CT scan) taken and interpreted in an emergency room
Describe trauma epidemiology.
- trauma remains the leading causes of death in those below age 50 (or 45?), and 4th leading cause of death overall – accounts for 10% of all deaths
- relative risk of death following major trauma is reduced by up to 20% when patients are treated in designated Level I trauma centers compared to non-designated centers
- with the advent of whole-body CT scanning (WBCT) protocols at most major trauma centers, it is becoming rare for ‘damage control’ surgery to be performed blindly without the use of pre-operative CT imaging
One study reported that up to 78% of major trauma cases may present in the ‘off-hours’ including evenings, nights, and weekends.
What is the problem with this?
What can mitigate this problem?
- these are times when hospitals tend to be understaffed
- problematic given that delays are correlated with worse patient outcomes in trauma – this may partly explain why mortality rates are higher among patients admitted on weekends
- availability of standardized and rapid WBCT imaging can assist with mitigating these risks and thereby lead to improved patient outcomes
What are the most significant mortalities and morbidities in trauma?
- hemorrhagic shock
- brain injury
Who is imaged with WBCT?
- category I: mechanism of trauma
- category II: clinical apparent injuries
- category III: vital signs
if one parameter is positive, serious injuries in one or more organ systems are suspected and WBCT is initiated
WBCT vs. Selective Meta-analysis
Review of 11 studies (32,207 pts) from 2007-2016 (including REACT-2 trial).
despite WBCT group having higher baseline injury severity scores:
WBCT mortality
- lower overall mortality rate
- lower 24 hr mortality
WBCT length of stay
- spent 15 minutes less in the ER
- spent 2 days less in the ICU
- spent 2 days less on ventilation
What is dual-energy computed tomography (DECT)?
2 x-ray sources and 2 data acquisition systems mounted on same x-ray gantry
- simultaneous low and high energy images can be reconstructed with comparable image noise levels
- attenuation measurements at two different tube voltages (80 kV and 140 kV) can be subjected to material decomposition, allowing for subtraction, addition, colour-coded iodine maps, quantification of iodine
Why is post-mortem CT needed to determine cause of death?
- physical examination is unreliable in polytraumatized patients at determining the extent of injuries and cause of death
- PMCT has the potential to identify traumatic injuries and determine the cause of death occult to the clinical team, in a non-invasive manner, with the ultimate goal of improving trauma care at a population level
What technique has traditionally been the gold standard investigation for cause of death?
autopsy – but its applicability is limited
- low utilization rate
- invasiveness
- time to perform procedure
- limited resources, cost
Describe the history of post-mortem CT imaging.
- x-rays have been used for > 100 years
- PMCT first performed in 1977
- PMCT angiography first described in 2011
What are the strengths of post-mortem CT (PMCT)?
- non-invasiveness
- availability, low cost
- short acquisition time
- digital data storage
- remote interpretation
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more SE, SP than autopsy
- bone injuries (skeleton, spine, face)
- air collection
- mediastinal shift
- intraventricular hemorrhage
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- position of medical devices – feedback 1st responders
- localization of foreign bodies – internal ballistics
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- ↑ accuracy of trauma registry change / ↑ ISS score
- accurate roadmap for autopsy
What are the weaknesses of post-mortem CT (PMCT)?
low soft tissue contrast – ↓ sensitivity in detection of:
- soft tissue injuries
- superficial injuries
- organ injuries
- vascular injuries
- if no IA/IV contrast
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- field of view limitation
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- unfamiliarity of radiologists in interpreting studies
- uneasiness of technologists in presence of diseased patients
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- legal and ethics implication towards coroner, consent to be obtained
What role does artificial intelligence (AI) play?
- has potential to increase diagnostic confidence
- optimizes workflow through better triage of patients
- improves diagnostic efficiency to meet increasing demands
AI-supported integrations:
- optimizing order entry for imaging studies
- streamlining image protocolling/image acquisition
- post-processing and decision support
When does the role of emergency radiologists begin?
the role extends beyond interpretation of images and begins when the patient arrives in the ED
