The provision of high-quality compressions with minimal interruptions is central to the management of cardiac arrest. Along with defibrillation, high-quality compressions are the only interventions proven to improve patient-oriented outcomes. Recently, point-of-care ultrasound (POCUS) has gained greater use in cardiac arrest care for determination the cause of arrest as well as guiding the resuscitation and interventions. Performance of POCUS during arrest can be challenging particularly in terms of obtaining cardiac windows. Among these challenges is obtaining images of the heart during compressions. As a result, cardiac POCUS is often performed during rhythm checks when there is a scheduled pause in compressions. Despite the potential benefit from POCUS, prolonged interruptions in compressions while attempting to get optimal windows is unlikely to benefit the patient and, may be harmful.

Clinical Question

Does the use of POCUS during cardiac arrest care alter the duration of pauses in compressions?


All patients presenting to a single, academic ED who either presented in cardiac arrest or experienced cardiac arrest in the ED.


POCUS used during rhythm check


POCUS not used during rhythm check


Primary: The differences in CPR pause duration with and without the use of POCUS in Cardiac Arrest?


Prospective cohort study


Traumatic arrest, patients with ROSC prior to ED arrival, fewer than 2 CPR pauses or if the resuscitation was not videoed.

Primary Results

  • 24 cardiac arrest patients enrolled (out of a total of 82 arrest that were resuscitated in the time period)
  • 110 CPR pauses with rhythm check in 86 of the pauses

Critical Results:

  • Ultrasound used for any pulse check: 69% (59/86)
  • Duration of pulse check (primary outcome)
    • Without POCUS: 14.2 seconds (95% CI: 11.1 – 17.4)
    • With POCUS: 19.3 seconds (95% CI: 16.5 – 22.0)
    • Diff: 5.0 seconds (95% CI: 0.9 – 9.1 p < 0.0001)
  • When resus leader also performed POCUS, association with 6.1 second longer CPR pause (95% CI 0.4 – 11.7)
  • US fellowship trained attending associated with shorter CPR pause vs non-US fellowship trained: – 3.9 seconds (95% CI – 8.4 to 0.7)

Duration of Pulse Check (seconds)

95% Confidence Interval

Without POCUS


11.1 – 17.4



16.5 – 22.0



0.9 – 9.1


  • Prospective, cohort study with videotaped resuscitation removing recall bias and ensuring accurate times
  • All video footage was reviewed by two data abstractors
  • Performed analysis and recorded experience level of person performing US
  • Adds to the scant literature on the topic of US impact on pauses during cardiac arrest care


  • Does not look at patient centered outcomes
  • Small study and most of the cardiac arrests that occurred were not included due to absence of video
  • Absence of explanation of pauses without rhythm check
  • Single center study reduces external validity

Author's Conclusions

“In this prospective cohort trial of 24 patients with CA, POCUS during CPR pauses was associated with longer interruptions in CPR.”

Our Conclusions

The use of intra-arrest POCUS was associated with an increased length of rhythm checks and, thus, an increased length in compression interruptions.

Potential Impact To Current Practice

While this study is too small to show an effect on patient outcomes from prolonged interruptions, everything in the existing literature tells us that longer interruptions will lead to worse outcomes. Regardless of whether POCUS is used intra-arrest or not, interruptions in compressions should be minimized. Extending rhythm checks to obtain good US images is not acceptable.
The use of POCUS intra-arrest or of POCUS driven arrest care must be thoughtfully applied to reduce potentials for harm. Employing transesophogeal echo for assessment of compression quality, assessment of rhythm and reversible etiologies may be a superior approach as compression interruptions are unnecessary.

Bottom Line

Intra-arrest POCUS may increase the duration of rhythm checks which has the potential to worsen outcomes. Providers should be cautious to not allow POCUS to interfere with interventions proven to be beneficial (compressions and defibrillation). More research is required to investigate why interruptions are longer, potential benefits of POCUS in arrest and the impact of prolonged pauses in this situation.

Read More


Huis in’t Veld, MA et al. Ultrasound use during cardiopulmonary resuscitation associated with delays in chest compressions. Resuscitation 2017. PMID: 28754527

Read More

REBEL EM: Beyond ACLS: POCUS in Cardiac Arrest

REBEL EM: The REASON Trial: POCUS in Cardiac Arrest

Core EM: ED POCUS in OHCA – The REASON Study

Core EM: Impact of US Guided Cardiac Arrest Resuscitation on Compression Pauses