Washington University Emergency Medicine Journal Club – September 22nd, 2022
Vignette:
You are working a shift in TCC when you get a pager about a 68-year-old gentleman with a history of atrial fibrillation who was found pulseless after passing out during his weekly golf game. Bystander CPR was initiated and upon EMS arrival his first rhythm was ventricular tachycardia. He was shocked x 2 with brief return of ROSC and then went into PEA. EMS reports that he was down 10 minutes prior to their arrival and they were on scene for 15 minutes.
On arrival to ED, CPR is in progress. You notice a middle-age male, normal BMI, no external signs of trauma. He is in PEA and is receiving ACLS. On the next pulse check, he gets ROSC and is orotracheally intubated without event. Current vitals signs are HR 107 with a wide complex, MAP 50, ETCO2 19. You are preparing an epinephrine infusion and grabbing the ultrasound when he goes into a ventricular arrhythmia. ACLS is re-initiated and an antiarrhythmic is delivered.
As you are grabbing the ultrasound, you wonder if you should use transesophageal echocardiography (TEE) during this cardiac arrest. You proceed to grab the transthoracic echo (TTE) probe and have limited visibility during 10 second breaks in CPR. ACLS is continued for an additional 15 minutes with PEA.
It has now been 25 minutes of ACLS without ROSC in your ED. Resuscitation efforts are ceased. Being an astute reader of the literature and attentive resident, you remember that the ultrasound division has been talking about the increasing benefits of TEE over TTE during medical cardiac arrest. That night after your shift, you wonder if you should have performed a TEE to guide ACLS. Unable to sleep, you email Wendy Huang to sign up for focused TEE training in cardiac arrest and head online to search the literature for answers…
PICO Question
Population: Intubated adult patients with any indication for bedside cardiac
echocardiogram (cardiac arrest, hypotension, etc.)
Intervention: Transesophageal echocardiogram by an emergency
Comparison: Transthoracic echocardiogram or standard or care
Outcome: Feasibility, ability to obtain interpretable images, any change in
management, mortality, ROSC, length of stay
Search Strategy
The four most relevant articles were selected by experts in Emergency Medicine,
Critical Care, and Ultrasonography.
Article 1: Teran F, Dean AJ, Centeno C, Panebianco NL, Zeidan AJ, Chan W, Abella BS. Evaluation of out-of-hospital cardiac arrest using transesophageal echocardiography in the emergency department. Resuscitation . 2019;137:140-7. Answer Key.
Article 2: Arntfield R, Pace J, Hewak M, Thompson D. Focused transesophageal echocardiography by emergency physicians is feasible and clinically influential: Observational results from a novel ultrasound program. J Emerg Med. 2016;50(2):286-94. Answer Key.
Article 3: Reardon RF, Chinn E, Plummer D, Laudenbach A, Rowland Fisher A, Smoot W, Lee D, Novik J, Wagner B, Kaczmarczyk C, Moore J, Thompson E, Tschautscher C, Dunphy T, Pahl T, Puskarich MA, Miner JR. Feasibility, utility, and safety of fully incorporating transesophageal echocardiography into emergency medicine practice. Acad Emerg Med . 2022;29(3):334-43. Answer Key.
Article 4: Fair J,III, Mallin MP, Adler A, Ockerse P, Steenblik J, Tonna J, Youngquist ST. Transesophageal echocardiography during cardiopulmonary resuscitation is associated with shorter compression pauses compared with transthoracic echocardiography. Ann Emerg Med . 2019;73(6):610-6. Answer Key.
Bottom Line
Cardiopulmonary resuscitation (CPR) in the emergency department is a
multidisciplinary effort to save a patient’s life. Minute changes in CPR quality, such
as identifying the area of maximum compression, and the percentage of hands-on
time, correlate strongly with overall survival. Despite low survival rates of cardiac
arrests, the goal of every emergency physician is to give everyone who presents to
the ED in cardiac arrest the best chance of walking out of the hospital.
Emergency physicians frequently employ echocardiography to assist in diagnosis
and therapy for patients with arrest or hemodynamic instability. The internal
placement of a TEE probe during cardiac arrest has been shown to decrease CPR
pauses by close to 50% when compared to TTE. The questions, then, become: how
feasible is it to implement ED-wide TEE adoption, how safe is the procedure, and
what additional clinical bene>its can TEE provide in critically ill patients? The
articles selected aim to provide some insight to the above questions.
The >irst article was a prospective observational study of emergency medicine
physicians at an urban university medical center (Teran 2019); it included only nontraumatic
out-of-hospital cardiac arrest cases. The study enrolled 33 patients, of
whom 21 (64%) had ongoing CPR, while 12 (36%) presented with ROSC. Four
views, called resuscitative TEE views (mid-esophageal 4 chamber, mid-esophageal
long axis, trans-gastric 2 chamber, and bicaval) were obtained in all cases.
Resuscitative TEE was used to assist in diagnosis, assess cardiac activity, and assess
CPR quality by identifying the area of maximal compression. TEE detected 12 cases
of >ine v->ib, 12 cases of RV dilation, and found that the area of maximum
compression was identi>ied over the aortic root/LVOT in 53% of cases. The authors
concluded that TEE was feasible and clinically impactful for out-of-hospital cardiac
arrests. The limitations of the study include: small, single institution study, not well
generalized; all TEE exams were performed by 7 EM physicians, 5 of whom were
investigators for the study; concern for investigator bias with 30/33 studies
supervised by the clinician who oversees the TEE resuscitative program.
The second article discussed the feasibility, >indings, and clinical in>luence observed
from the >irst TEE program implemented in an ED POCUS program (Arnt>ield 2016).
The study also examined the presence of any complications related to TEE. It was a
single centered retrospective observational study of 54 TEE examinations
performed by 12 emergency physicians. The most common indications for TEE were
cardiac arrest (43%), post-arrest management (26%), and undifferentiated shock
(40%). Probe insertion was successful in all cases. TEE imparted a diagnostic
in>luence in 78% of cases and impacted therapeutic decisions in 67% of cases. The
authors were able to conclude that ED-based TEE showed a high degree of feasibility
and clinical utility, with a diagnostic and therapeutic in>luence seen in the majority
of cases. The main limitation of the study was that the number of cases included was
very small compared to the total number of cardiac arrest cases at the institution.
The third article discussed resuscitative TEE feasibility involving images obtained
mostly by faculty with no advanced ultrasound training (Reardon 2022). It showed
that 4 hours of focused TEE training was adequate and that 99% of the images
obtained were clinically relevant (YOU CAN DO IT). It was a retrospective analysis of
a continuous QI database of patients who presented to Hennepin County Medical
Center. There was no set protocol or algorithm for TEE use; clinicals were free to use
it whenever they thought it would be helpful for intubated patients with shock,
cardiac arrest, or peri-arrest. This is the only study where all ED faculty, full and part
time, were trained in TEE use, with the majority of faculty having no advanced US
training beyond residency. The study reported 557 TEE studies performed by 52 EM
physicians over a 42-month period. The primary outcome of the study was whether
the provider was able to obtain interpretable f-TEE images during the resuscitation
(able to insert the probe, obtain images, and interpret them). The secondary
outcome measures included the quality of images and post-procedural
complications. The results were quite encouraging: 75% of studies were performed
by non-ultrasound faculty; physicians were able to obtain viewable image 99% of
the time (with no difference between non-US faculty and US faculty); the quality of
recorded images was considered “good” in 85.9% of cases, fair in 9.7%, and poor in
only 4.5%.
The fourth paper reported on the evidenced-based bene>it of TEE, speci>ically
reduction in pulse-check time during CPR (Fair 2019). This was a retrospective
analysis of video recordings obtained routinely for quality improvement purposes
during CPR, conducted at a level 1 trauma center and tertiary care facility. The
authors compared the duration of chest compression pauses between TEE, TTE, and
manual pulse checks on video recordings of CPR. A total of 25 patients were enrolled
for a total of 139 pulse check CPR pauses; 69 pauses for procedures/other
resuscitative activities were not included. The results revealed that:
o TEE provided the shortest mean pulse check duration or 9 seconds
o TTE mean pulse check duration was 19 seconds
o Manual check mean duration was 11 seconds
The study was limited by its retrospective nature, with pulse check times
extrapolated from video review; it included both medical and traumatic cardiac
arrests; it was a single center study; and all operators performing TEE were USfellowship
trained.
Overall, this data suggests that implementation and performance of emergency
department resuscitative TEE is feasible. A provider does not need advanced
ultrasound training to learn and perform TEE, as long as a regimented teaching
protocol is in place. In addition, resuscitative TEE is a safe procedure with very low
complication rates. One of the biggest foreseeable bene>its of TEE use in cardiac
arrest revolves around reduced pulse-check time, which has strong correlation with
patient survival. In addition, TEE can provide real-time feedback on CPR quality, and
information regarding potentially reversible patient pathologies. It should be noted
that thus far, no studies have demonstrated bene>it in terms of patient-centered
outcomes. In the future, this skill can potentially be used beyond cases of medical
cardiac arrest to bene>it critically ill, intubated patients in the emergency
department.