Early Head-to-Pelvis CT for OHCA
May 6, 2021
Written by Jonathan Brewer
Obtaining an expedited CT head-to-pelvis after resuscitation from idiopathic out-of-hospital circulatory arrest (OHCA) appears to be safe and may help identify and rule out critical life-threatening diagnoses and change clinical management.
Why does this matter?
Many times, we are simply told “CPR in progress via EMS. ETA 5 minutes.” It’s our job to make sure we assess for reversible causes and perform our job as the experts of resuscitation. However, it is often difficult to obtain a good history and determine the exact cause of cardiac arrest once the patient is resuscitated and return of spontaneous circulation (ROSC) is achieved. Could an early head-to-pelvis CT assist with our workup and safely identify potential causes of OHCA?
“Just send ‘em to the donut of truth”
This was a prospective, observational cohort study of 104 patients who had OHCA without obvious cause (idiopathic OHCA) status post ROSC. These patients were enrolled in an early “sudden-death” CT (SDCT) protocol within 6 hours of hospital arrival that included a non-contrast CT head, an electrocardiogram-gated cardiac and thoracic CT angiogram, and a non-gated venous-phase abdominopelvic CT angiogram. Of note, patients that needed emergent cardiac catheterization or were too hemodynamically unstable for SDCT were excluded from this cohort.
Based on this study, scans occurred within 1.9 +/- 1.0 h of hospital arrival and identified 39% (41/104) of all causes of OHCA and 95% (39/41) of all causes potentially identifiable by SDCT. SDCT was also useful for identifying life-threatening complications of the resuscitation in 16% of patients such as pneumothorax/thoracic organ injury (n=8) and complications from a liver or spleen laceration (n=6). In addition, in 13% of cases, SDCT determined causes of OHCA that would not have been identified by standard of care without CT scanning. Overall, 28% of patients developed acute kidney injury (AKI), but only 1 patient required initiation of dialysis. Of note, transient renal dysfunction is very common after OHCA (40-50%) and so the incidence of AKI in the study may not be related to iodinated contrast exposure from SDCT. No other significant safety outcomes were noted.
What I take from this study is that early head-to-pelvis CT appears to be a safe procedure that can rapidly identify potential causes of OHCA and could significantly change a patient’s management in the post-ROSC scenario.
Edited and Peer Reviewed by Sam Parnell
Early head-to-pelvis computed tomography in out-of-hospital circulatory arrest without obvious etiology. Acad Emerg Med. 2021 Apr;28(4):394-403. doi: 10.1111/acem.14228. Epub 2021 Mar 24.