Brown Ultrasound Tape Review: 10/15/15
Article 1: FAST Exam to Predict Survivors of ED Thoracotomy
Inabi, et al. FAST Ultrasound Examination as a Predictor of Outcomes After Resuscitative Thoracotomy. Annals of Surgery 262(3):512-518, 2015.
Fresh off the trauma surgical press last month, this study examined the utility of FAST exam (specifically parasternal and subxiphoid cardiac views) to predict positive outcomes (survival to discharge or organ donation) of ED resuscitative thoracotomy (RT).
This was a prospective cohort study at LA County/USC Medical Center. In 3.5 years, 187 patients arrived in traumatic arrest and underwent FAST and RT (that’s 4-5 thoracotomies a month – WOW!). They documented +/- pericardial fluid and +/- cardiac motion. PGY2-4 EM residents performed the FAST exams after some formal training, and they were supervised by “faculty” – not clear if those were surgeons or EM attendings.
About ½ patients lost vitals at the scene and another ¼ both en route and in the ED. Overall survival – 6 patients (3.2%). Overall organ donation – 3 patients (1.6%). Cardiac motion on FAST was 100% sensitive for the identification of survivors and organ donors (and 73.7% specific). While the tables and discussion include a lot on the presence or absence of pericardial fluid, this did not impact the sensitivity or specificity of FAST. If cardiac motion was absent, the likelihood of survival was 0.
Bottom line: Given that RT is such a high risk, low survival procedure, cardiac FAST can be used (with excellent sensitivity) to identify traumatic arrest patients with better odds of survival or organ donation from ED thoracotomy. No cardiac motion means pretty much no chance of survival or organ donation.
Article 2: Handheld E-FAST for Pneumothorax
Kirkpatrick, et al. Hand-Held Thoracic Sonography for Detecting Post-Traumatic Pneumothoraces: The Extended Focused Assessment With Sonography for Trauma (EFAST). Journal of Trauma 57:288-295, 2004.
This was another trauma surgery study out of Vancouver Hospital and Health Sciences Centre interested in the test characteristics of hand-held US to look for PTX in trauma patients. They compared EFAST examinations for PTX to:
(1) CXR results
(2) a “composite standard” of clinical information, which included some combination of CXR, CT if it happened, clinical course, and need for chest tubes/needle decompression
(3) CT alone (the gold standard for patients who had a CT).
This was a retrospective chart review on trauma patients (note – those who were in “physiologic extremis” with suspected PTX were excluded). All EFASTs were done by the attending trauma surgeon using a linear transducer. They looked for lung sliding or comet tail artifacts or color power Doppler evidence of pleural sliding in at least 3 rib spaces. PTX was diagnosed if neither sliding nor comet tail artifacts were seen.