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 cardiac 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.
Article: Huis in’t Veld, MA et al. Ultrasound use during cardiopulmonary resuscitation associated with delays in chest compressions. Resuscitation 2017. PMID: 28754527
Clinical Question: Does the use of POCUS during cardiac arrest care result in prolonged interruptions of compressions?
Population: Patients > 18 years of age presenting to the ED in cardiac arrest or suffering an arrest in the ED.
Intervention: POCUS used during rhythm check
Control: POCUS not used during rhythm check
(Primary): Duration of rhythm checks in cardiac arrest patients with POCUS employed versus those without POCUS employed
Design: Prospective cohort study
- Patients < 18
- No documentation of a rhythm check
- Were not resuscitated in a designated resuscitation room with continuous video monitoring
- Video recording not available or image quality too poor
- 23 cardiac arrest patients enrolled
- 123 individual rhythm checks
- Survival to ED discharge/hospital admission: 35% (8/23)
- Survival to hospital discharge: 4% (1/23)
- Survival at 30 days: 4% (1/23)
- Number of pulse checks/patient: Median = 6 (range 1-11)
- Ultrasound used for any pulse check: 83% (19/23)
- Duration of pulse check (primary outcome)
- Effect of performance of a procedure
- Increased duration of pause by 2.9 seconds (95% CI: 1.2 – 4.6)
- Not statistically significant
- Data collection was prospective and researchers were notified of an arrest by an automatic email sent by the EMR
- All videos reviewed by two team members with a third member available if any discrepancies occurred
- Video data collection obviated concerns for recall bias
- Did not look at a patient centered outcome
- Single center study reduces external validity
- Unclear of the level of training with US of individuals performing the US
- Due to low survival rate, cannot comment on benefit of POCUS
- Small sample size may underestimate benefits of POCUS
- Unclear why POCUS performed on some cardiac arrest patients but not others and during some rhythm checks but not others
- No information on what the POCUS operator was looking for or what prompted POCUS
Authors Conclusions: “The use of POCUS during cardiac arrest resuscitation was associated with significantly increased duration of pulse checks, nearly doubling the 10-second maximum duration recommended in current guidelines. It is important for acute care providers to pay close attention to the duration of interruptions in the delivery of chest compressions when using POCUS during cardiac arrest resuscitation.”
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 to Impact 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.
For More on This Topic Checkout:
- 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
- Rory Spiegel at EM NERD (EMCrit): The Case of the Bridge to Nowhere Continues
- Ultrasound Podcast: Don’t Lolly-Gag Around with that Ultrasound Probe During the Pulse Check
- Ultrasound Podcast: Does US Delay Pulse checks in Cardiac Arrest?
Post Peer Reviewed By: Salim R. Rezaie (Twitter: @srrezaie)