Editorial
Scanning for the Full Picture: Building Evidence for Imaging After In-Hospital Cardiac Arrest
Nicholas J. Johnson, Kelley R.H. Branch
Chest 2026; 170: 15-16
https://doi.org/10.1016/j.chest.2026.02.011
The 2025 American Heart Association (AHA) guidelines mark an important evolution in postcardiac arrest care by introducing a Class IIb recommendation that it may be reasonable to perform advanced imaging after the return of spontaneous circulation (ROSC), specifically head-to-pelvis CT scans and point-of-care ultrasound (POCUS) scans.1This recommendation rests primarily on evidence from out-of-hospital cardiac arrest (OHCA) where undifferentiated arrest is common and clinical information is often sparse.2, 3, 4 Although physiologic overlap exists between OHCA and in-hospital cardiac arrest (IHCA), their clinical contexts often differ. OHCA usually occurs away from immediate emergency medical care with incomplete prior arrest history, and the causes of OHCA can range widely from acute coronary syndrome to drug overdose to intracranial hemorrhage to trauma. By contrast, IHCA typically unfolds in monitored hospital wards or ICUs with readily available prior arrest clinical information. ICHA often results from decompensation of severe, known illnesses or complications that result from inpatient care. The rationale for imaging between OCHA and IHCA, especially to identify arrest cause, may not align between the 2 populations, and the diagnostic yield of imaging studies could differ substantially. Transporting an unstable patient with IHCA for CT scanning also introduces logistical and clinical risks not present in the emergency department where standardized workflows and diagnostic imaging are readily available.5
To partially fill this gap, Andrea et al6 in this issue of CHEST described a 4-center, retrospective cohort study of 345 patients with IHCA who achieved ROSC. They examined the utility of clinically ordered CT scans and POCUS scans within 48 hours of ROSC and reported the key process outcomes of diagnostic yield and change in clinical treatment. The CT scans most commonly imaged the head, followed by chest and abdomen/pelvis. Across all CT scans performed, nearly two-thirds revealed new information; approximately the same proportion prompted changes in treatment. Chest CT scans had the highest yield by identifying new findings in more than 90% of scans and changed treatment plans for nearly two-thirds of patients, in alignment with prior OHCA data.2,7In contrast, head CT scans had a lower yield, with only one-quarter of patients showing new findings and fewer resulting in changes to treatment. This differs from prior OHCA studies where head CT scans had abnormal findings in up to one-half of patients and where underlying causes of OHCA were uncovered in approximately 1 in 5 cases.1,8,9
POCUS were used even more frequently, were performed in more than three-quarters of patients, and most often were images of the heart or lungs. Again, the yield was substantial, with more than one-half revealing previously unknown findings and more than 40% prompting changes in care. POCUS revealed the likely cause of arrest in nearly 20% of cases. Cardiac POCUS was the highest yield modality, but thoracic ultrasound scans also identified pulmonary edema, consolidation, and pleural pathologic evidence. Importantly, POCUS could be performed rapidly at the bedside, with a median time from ROSC to imaging of just over 2 hours compared with over 6 hours for CT scans. Prior literature has demonstrated feasibility and reasonable diagnostic yield with POCUS and echocardiography.10,11
This multicenter study demonstrates that CT scans and POCUS performed early (< 48 hours) after ROSC in IHCA survivors yielded common, clinically important findings that often lead to changes in treatment. In particular, the yield of CT chest scans suggests that thoracic imaging should be prioritized in IHCA, where pulmonary processes such as aspiration, pneumonia, pulmonary embolism, and pleural pathologic findings and resuscitation complications are common. Isolated head CT scans had a lower diagnostic yield and impact in this cohort compared with OHCA data and could be individualized. POCUS, with its rapid availability at the bedside and negligible risk, was similarly valuable and able to identify time-critical problems before CT scans.
Together, these findings further support the 2025 AHA recommendations for post-arrest imaging, albeit with important caveats, limitations, and bias that are common with retrospective data. For example, this study does not address whether an empiric full-body CT scan strategy is superior to more selective CT scan approaches after IHCA. As a retrospective observational study, the analysis relied on clinical documentation, which may incompletely capture imaging indications, findings, or the nuances of treatment decisions. Confounding by indication is also possible because patients who did not undergo CT scans could have been too unstable for transport or conversely deemed stable enough not to require imaging, although illness severity scores did not differ between groups. Neither hospital had a formal protocol for after arrest imaging, so observed patterns reflect selection bias that can affect diagnostic yield and generalizability. The study also did not assess adverse effects systematically, such as CT scan contrast-associated acute kidney injury, although prior research in OHCA populations has not demonstrated an increased incidence of acute kidney injury.12 This study did not evaluate direct links between imaging and patient-centered outcomes such as survival or neurologic recovery. Finally, imaging reviews were not blinded, and abstractors considered broader medical record context along with radiology reports, possibly introducing potential observer bias.
In conclusion, this study fills an important evidence gap by quantifying the utility and safety of early imaging in IHCA, which is a population underrepresented in the after arrest literature. These results support the 2025 AHA recommendations and highlight the value of integrated imaging strategies that create a “full picture” after cardiac arrest by combining POCUS for urgent bedside evaluation with CT scans for comprehensive, detailed imaging. Future studies should evaluate the effect of individualized or clinician-driven vs universal imaging after IHCA on patient outcomes, as well as impacts on operational efficiency and resource utilization.
