Ultrasound Associated with Delays in Chest Compressions

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Ultrasound use during cardiopulmonary resuscitation is associated with delays in chest compressions

Resuscitation July 2017 (Epub) - Pubmed Link


Take Home Points

1.Ultrasound during arrest poses risk for delay in chest compressions.

2. This doesn’t mean stop doing it, just do it judiciously and quickly.


Background

Lots of clinicians use point of care ultrasound during cardiac arrest. There is some evidence that cardiac activity on ultrasound is associated with survival (see prior post on REASON trial). In addition, you can potentially diagnose a cause for the cardiac arrest and intervene. Now, we know that in cardiac arrest, perfusing the brain and heart are key to good outcomes. Although ultrasound is commonly used, there is the risk that using it could lead to more time off the chest, meaning less time that that the coronary arteries and brain are getting oxygen. This paper aims to discover whether or not performing an ultrasound is associated with longer periods between chest compressions.


Questions

Does POCUS during cardiac arrest lead to longer delays in chest compressions?


Population

Single adult ED, tertiary care academic medical center


Inclusion

  • ≥18 years old

  • Cardiac arrest (either prior to arrival or while in ED)

Exclusion

  • < 18 years old

  • No pulse check documented

  • Not in one of three rooms with video monitoring

  • Video not available or poor image quality


Design

Prospective cohort study

Patients identified by receipt of documentation of arrest

Videos analyzed by two team members

Timed pulse checks (from compression pause until resuming compressions)

Stratified by whether or not POCUS was used during pulse check

Procedures were also documented

Outcome = duration of pulse checks with POCUS compared to duration of pulse checks without POCUS

Linear mixed-effects model

Power calculation determined that 8 patients in each group needed


Intervention

Patients underwent resuscitation per direction of treating team.

There was no specific ultrasound intervention. When ultrasound was used during a pulse check, this was documented by the investigators reviewing the video footage.


Who did the ultrasounds?

Not mentioned in article.


The Scan

Not mentioned in article.

Presumably a subxiphoid or PLAX cardiac view with either the phased array or the curvilinear tranducer

phased array


Generally, there are a few focused questions you are addressing simultaneously:

Is the heart beating?

Does it look like ventricular tachycardia or ventricular fibrillation?

Is there evidence of cardiac tamponade?

Is there evidence of right heart strain suggesting an acute pulmonary embolism?

Here's a great lecture by Dr. Felipe Teran (@FTeranmd) all about POCUS in Arrest


Results

23 patients enrolled → 123 pulse checks


Primary Outcome

Mean duration of pulse checks

POCUS: 21 seconds (CI 18-24)

Without POCUS: 13 seconds (CI (12-15)

Difference: 8.4 seconds


Other Findings

Age and BMI did not affect duration of pulse checks

Procedures increased duration by 2.9 seconds but not statistically significant

No POCUS images prompted procedure (like a pericardiocentesis)

1/23 patients survived


Limitations

Small study, single center

Convenience sample - only when patients were in certain rooms.

It is unclear the level of training of those performing the ultrasound - perhaps more experienced providers could avoid this delay?

Using transesophageal echocardiography can potentially avoid these delays by providing continuous imaging throughout chest compressions

Since there was no standardized protocol or instruction given to the people performing the ultrasound, the time difference observed is not unavoidable.


Pointers on Performing (Transthoracic) Ultrasound in Cardiac Arrest

  1. Get ready prior to pulse check. Machine on, probe with gel in hand. Have a count down to pulse check.

  2. Obtain an image as quickly as possible, save a clip, then move away so compressions can restart. Interpret the clip after moving away (even if after compressions have restarted)

  3. There should be a separate person keeping track of time between compressions (counting out loud or giving verbal reminder) to avoid time off the chest (ideally <10 seconds total).


Take Home Points

1.Ultrasound during arrest poses risk for delay in chest compressions.

2. This doesn’t mean stop doing it, just do it judiciously and quickly.


Our score

4 Probes


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Published on 08/14/17 02:00 AM
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