TEE to Shorten Compression Pauses in Cardiac Arrest

TEE pulse check graphic

Transesophageal Echocardiography During Cardiopulmonary Resuscitation Is Associated With Shorter Compression Pauses Compared With Transthoracic Echocardiography

Ann Emerg Med Epub February 2019 - Pubmed Link


Take Home Points

1. In cardiac arrest, TEE unlike TTE, appears not to prolong interruptions in chest compressions compared to manual palpation.

2. This data supports the use of TEE in cardiac arrest, especially with consideration of other theoretical advantages not addressed in this study.

3. We need to do better with TTE, using it wisely and not discounting the modality altogether.


Background

Point of care Transesopheal echocardiography (TEE) is blowing up. Some say it’s use and popularity are outpacing the evidence to support it. In cardiac arrest, there are advantages of continuous evaluation of chest compressions, identifications of etiologies of arrest, and perhaps decreasing the time needed to evaluate for a pulse. The idea here is that you don’t need to wait for manual pulse if there is standstill on the TEE. Transthoracic echo (TTE) can sure be useful in cardiac arrest as well, but a few studies (Huis 2017, Clattenburg 2018) have shown that it can prolong pulse check time, which we know is bad for brains and hearts. Most experts agree that this can be fixed. You just have to be judicious with your timing, or perhaps use a specific protocol. Another option is to abandon TTE and use TEE. This study tries to assemble some evidence that TEE is a better solution, providing better information with less adverse effect to the patient.


Read more about the Evidence for Point of Care Echo here The Evidence Atlas - Echocardiography


Questions

Are TEE guided pulse and rhythm checks shorter than TTE or manual pulse and rhythm checks?


Population

Single US Center


Inclusion:

  • ≥18 years

  • Medical or traumatic cardiac arrest with CPR

  • Had to have had video captured and available


Design

Retrospective cohort

Abstractors reviewed digital recordings of all cardiac arrests available between March 1, 2016 and May 25, 2017

They timed pauses from time of last compression until start of next compression, rounded to 1 second.

All interventions were documented, such as ultrasound (transesophageal or transthoracic), intubation, arterial access, defibrillation, etc.

Pauses where only ultrasound and pulse check were performed were analyzed for timing.

Each pulse check was categorized by modality, the same arrest could have different modalities used.


Who did the ultrasounds?

Emergency physicians - residents or attendings. All trained and credentialed in ultrasound. A few (4) ultrasound fellowship trained attendings trained in TEE.


The Scan

Transesophageal Transducer

TEE


No specific protocol specified for this study


5minsono

5 Min Sono -TEE


thePOCUSAtlas

The Image Atlas - Echo


A ton of great TEE resources at ResuscitativeTEE.com including this excellent video that will convince you that you need TEE


Results

25 cardiac arrests (23 medical, 2 traumatic) → 208 pauses → 139 pauses where only ultrasound was done during pause (checks with other procedures performed were not analyzed)

N = 139 pauses

  • 22% TTE

  • 30% TEE

  • 47% palpation


Primary Outcome - Mean Pause Duration

TEE 9 s (CI 5-12 s)

TTE 19 s (CI 16-22 s)

Palpation 11 s (CI 8-14 s)

*No significant difference between TEE and Palpation but difference between TEE and TTE and Manual and TTE


Unadjusted Analysis

  • TEE 7 s (SD 5 s)

  • TTE 18 s (SD 8 s)

  • Palpation 10 s (SD 5 s)


Intraclass correlation for agreement was 0.99


Limitations

Retrospective. Single center.

Ultrasound checks may decrease as time goes on (since less information is needed each time). Resuscitations that went on longer could favor that modality with decreased times. If one of the modalities, by nature of the patients in which it was used, led to longer resuscitations - that would be a point of bias. This would really only matter for TTE because theoretically, you don't have to stop anything for TEE.

In this study, TEE use meant that an ultrasound fellowship trained attending was present. A prior study (Huis 2017) showed that this alone reduces time of compressions for TTE. Presumably, this is because people are wasting less time interpreting, or perhaps they are more attentive to the risk of delays. However, since we cannot know the specific mechanism by which this advantage is conferred, perhaps it could also have improved the TEE times as opposed to TTE times where there may not have been an ultrasound fellowship trained attending present.


Discussion

Is this evidence enough to advocate for TEE in cardiac arrest? This is a complex issue. First of all, if it turns out TEE is superior - will that mean that every emergency department needs to purchase a TEE and train all faculty in TEE? That is a big undertaking to impose, especially on a small community center. Secondly, could doing TTE correctly eliminate the advantage of TEE? Unclear. There are many other potential advantages to TEE, but not much evidence for those...yet.

If we do not have TEE, should we just stop doing echoes during cardiac arrest? NOOOOOOoooooooooo! As we have tried to hammer home, TTE can still be done as long as you are cognizant of the risks and intentional about mitigated them. These are simple things: be prepared prior to stopping compressions (get a window while compressions ongoing), save a quick clip and interpret it afterwards, and FOR PETE'S SAKE JUST HAVE SOMEONE TIMING THE PAUSES. The point is that there are advantages to using TTE during cardiac arrest that should not be discarded without a fight. Instead of giving up on TTE, just learn/teach to do it better.


Take Home Points

1. In cardiac arrest, TEE unlike TTE, appears not to prolong interruptions in chest compressions compared to manual palpation.

2. This data supports the use of TEE in cardiac arrest, especially with consideration of other theoretical advantages not addressed in this study.

3. We need to do better with TTE, using it wisely and not discounting the modality altogether.


More Great FOAMed on this Topic

Ultrasound Podcast - Does US delay pulse checks in cardiac arrest?


Our score

4 Probes


Expert Reviewer for this Post

Liu

Rachel Liu, MD @RubbleEM

Assistant Professor, Emergency Ultrasound Fellowship Director, and Director of Clinical Ultrasound Education for Yale School of Medicine


Cite this post as

Michael Prats, MD. TEE to Shorten Compression Pauses in Cardiac Arrest. Ultrasound G.E.L. Podcast Blog. Published on March 18, 2019. Accessed on November 15, 2019. Available at https://www.ultrasoundgel.org/65.
Published on 03/18/19 06:00 AM
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