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Three Part Question

Is [cardiac ultrasound] useful to [inform clinical decisions on treatment] for [patients in cardiac arrest in the Pre-hospital environment]

Clinical Scenario

A 36yr old male patient is found at home in cardiac arrest. Initial ECG shows PEA and the resus is continued for 20 mins with one episode of VF but no ROSC. The decision is made to take him to the nearest A&E but there is no improvement and he pronounced dead in A&E. You wonder if being able to perform cardiac ultrasound would have helped the decision to continue or terminate the resus

Search Strategy

Prehospital OR pre-hospital AND Echo OR ultrasound AND arrest
Searched Pubmed on 28th June 2018

Search Outcome

63 papers from intial search with 25 identified to read in full. An extra 5 papers were reviewed from the references.

13 papers were identified as the most relevant and/or good quality

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Breitkreutz R et al. November 2010 Germany	230 patients 100 in Cardiac arrest and 104 in a shock state (peri-resuscitation state)	Prospective observational study	FEEL examination	Emergency physician trained with a modified hand-held ultrasound device	Non-randomised study using registry data. Self-evaluation for whether therapy changed after ultrasound Small total numbers for each rhythm state Not all images could be later reviewed to confirm correct interpretation was made
			Image quality	Images of diagnostic quality found in 96%
			Rhythm detected	In 35% (13/37) of those with asystole and 75% (38/51) of those in PEA on ECG, coordinated cardiac wall motion was detected.
			Pericardial tamponade detected	5.4% of patients had pericardial effusions – PPEA (5/38) 13% and asystole 3/37 8% - not detected by other methods. All patients in PPEA with effusion gained a ROSC on pericardiocentesis
			Change in management	Altered management in 78% of case – 89% of cardiac arrest causes and 66% of peri-arrest as determined by EP
Price S et al. June 2010 United Kingdom	All patient ages	Literature review		Up to 45% of healthcare professionals cannot accurately palpate central pulses leading to early termination or initiation of resus. Echo is useful to identify cardiac motion	Majority of review focused on in-hospital rather than out-of-hospital use of echo
Cureton et al. July 2012 USA	318 patients in pulseless cardiac arrest following trauma 162 had EKG and Echo pre-hospital	Retrospective cohort database analysis	Survival to hospital overall	From 17 patients with cardiac motion on ultrasound, 4 survived to hospital (2.3%) From 64 patients with activity on EKG but not on echo, 4 survived to hospital (6%) Total 4.3% survival	Non-randomised study using registry data. Focus on trauma alone In many situations, ultrasound is skipped to perform thoracotomy
			Stratified by electrical activity on EKG and Echo	162 pulseless patients had an echo and EKG 135 patients had electrical activity on EKG, 71 of these had an echo performed and 17 of whom had cardiac motion
			Negative predictive values	Absence of cardiac motion in pulseless patients with trauma predicted death with a Negative Predictive Value of 99% so may be suitable to determine when resuscitation would be futile
Aichinger G et al. April-June 2012 Austria	42 patients in pulseless CPR Excluded under 18s and trauma patients Only included patients when physician staff available	Prospective observational study	Type of ultrasound examination	20 patients had Cardiac Echo alone and 22 patients had multiple examinations	Non-randomised study using registry data. Small sample size Ultrasound could not be checked for correct diagnosis after resus Patients with achieved ROSC after a short time of CPR did not get a ultrasound so there was a selection bias
			Survival	5/42 survived to hospital admission (11.9%)
			Survival and echo	10/42 had cardiac movement on first echo (23.8%). 4 survived to hospital admission (40%) Out of the 32 with no cardiac motion only 1 survived to admission (3.1%). Only 1 of the patients had survived to hospital had a good neurological outcome and survived past 3 days. He had electrical activity on echo
			Predictive values	Cardiac standstill at any time in resus had a positive predictive value of 97.1% for death at scene and negative predictive value of 57.1%
Busch M. July 2006 Norway	38 patients – 19 medical, 15 trauma, 1 obstetric and 3 excluded due to technical difficulties	Prospective cohort study over a 3 month period	Quality of ultrasound	74% considered good quality, 26% moderate quality	Not all patients in cardiac arrest as included other examinations such as FAST and lung examination so small numbers Single operator so images were not re-examined after the resus
			Medical endpoints	7 patients were in cardiac arrest and 4 in peri-arrest acute shock 3 patients from the shock group showed signs of cardiogenic shock with poor contractility on ultrasound 1 patient had PEA with minor pericardial effusion but was negative for effusion in the ED
Rooney KP et al. 2016 USA	19 patients with 17 deemed adequate images for clinical decision making Over 18 only and excluded pregnant women	Prospective educational study with a convenience sample of paramedics with some ultrasound experience Clips were reviewed by two trained physicians	Types of images	17 images of cardiac activity and 2 showing cardiac standstill	Small number of patients Focus on education and ability to perform echo rather than clinical decisions
			Paramedic reliability	100% of paramedics could distinguish between cardiac activity and standstill on the ultrasound
Salen et al. July 2005 USA	70 subjects over a 12 month period From 16yrs-92yrs 67/70 were pre-hospital cardiac arrest	Prospective cohort study	Rhythms by ECG	36/70 were in asystole, 34/70 were in PEA	Small total sample size The ultrasounds were not reviewed for accuracy
			Ultrasound frequency	Serial ultrasounds performed in 53 and single ultrasound in the other 17
			Ultrasound results	59/70 has no cardiac activity on ultrasound 23/36 with PEA had no cardiac activity on ultrasound 11/36 in PEA had some cardiac activity. Of these 8 achieved ROSC but 6 died within 11hrs of ICU admission
Byhahn C et al. January 2008 Germany	1 patient – Pregnant teenager with out-of-hospital cardiac arrest following a stabbing	Case report		Diagnosed pericardial tamponade during cardiac arrest leading to successful pericardiocentesis and positive outcome for the teenager	Case study so one case alone but shows use of ultrasound in rare cause of cardiac arrest
Ketelaars R et al. April 2013 Netherlands	326 patients of all ages had US examinations of the chest 39 US examinations during CPR in 31 patients (average 1.26 per patient in CPR)	Retrospective cohort study	Quality of image	Rated “good” in 55% of scans with moderate for 25% and poor for 4% of examinations	Some data missing Note data was not always clear on process for decision making Only change could be recorded after each US examination No on scene data as all retrospective entry
			Cardiac echo results	48 patients were shown to systolic, 17 had poor contractility and 12 with poor ventricular filling across trauma and primary CPR patients
			Effect on management	Management changed in 21% of cases. In 9/60 the decision to stop all treatment was made after cardiac echo In two trauma patients the decision to initiate ionotropic medication was made due to echo
Blaivas M and Fox JC June 2001 USA	169 patients Arriving to ED with CPR in progress	Prospective cohort study	Rhythm recognised	136 patients were in cardiac standstill on echo. 71 of these patients had a recognised rhythm on ECG.	The ultrasound took place within the ED so selection bias of patients brought to ED undergoing CPR
			Survival outcomes	No patient with cardiac standstill identified survived regardless of rhythm on ECG
			Predictive value	Positive predictor value of 100% for death in the ED with a negative predictive value of 58%
O’Dochartaigh D et al. January-February 2017 Canada	455 missions over a 5yr period	Retrospective data analysis over 5 year period Critical care Air ambulance team only	Number scanned	Cardiac scans were performed in 105 patients – 82 medical and 23 trauma patients	Scans done pre-hospital were not available for review Single organisation Data selection was not blinded
			Clinical decisions	Ultrasound used to decide continuation in 25 patients and decision to cease in 31 patients
			Cardiac echo reports	Cardiac activity reviewed in 79 cases. Found to be positive in 33 patients, negative in 38, and poor in 8
			Pericardial effusions present	Pericardial effusion detected in 4 cases and the check was negative in 29 cases
Salen, P et al. June 2001 USA	112 patients over 12 month period	Prospective cohort study	Cardiac activity	Presence of cardiac activity at any point during resus was associated with survival to hospital admission 11/41 (27%) Only 2/61 with no cardiac activity (3%)	Non-randomised protocol driven observational study Observational rather than focused on clinical decision making Images were not reviewed after resus
Gaspari et al. December 2016 USA and Canada	793 patients across 20 hospitals presenting with PEA or asystole	Prospective observational study	Survival outcomes	114 survived to hospital admission (14.4%) with 13 surviving to hospital discharge	Non-randomised protocol driven observational study Different timing to ultrasound
			Cardiac activity related to outcome	On multivariate regression modelling, cardiac activity was associated with increased survival to hospital admission (OR 3.6 (2.2-5.9)) Ultrasound also identified pericardial effusion and those had pericardiocentesis had a higher survival rate of 15.4%

Comment(s)

Many non-randomised studies have focused on the use of cardiac ultrasound during cardiac arrest in the pre-hospital environment. However, the studies suffer from similar drawbacks including the inability to review the images at a later point to check accuracy and many focus on feasibility or outcome alone rather than how the ultrasound affected the clinical decisions made. The difficulty in randomisation during these studies and retrospective design also increases selection and recall bias so the results are less reliable than other study designs. The clear majority of studies show ultrasound is a reliable technique with few reporting a significant proportion of poor quality images so could be used in the assessment of the patient. The main conclusion from these studies suggest cardiac standstill has a high predictive value for death but the presence of cardiac activity does not have a strong association with survival. The other use for echo was identified in a small number of patients who had pericardial effusion and underwent pericardiocentesis as a result of the ultrasound finding. Although this is a small number of patients per study they had increased survival compared to the other groups identified by ultrasound.

Clinical Bottom Line

Cardiac ultrasound is useful in cardiac arrest primarily for detection of cardiac activity and in the absence of activity can help the decision for termination of resuscitation. Ultrasound also provides a useful tool to detect pericardial effusion although this is not a common cause of arrest

References

1. Breitkreutz R et al. Focused echocardiographic evaluation in life support and peri-resuscitation of emergency patients: a prospective trial. Resuscitation 2010; Volume 81, Issue 11, 1527-33
2. Price S et al. Echocardiography in cardiac arrest. Current Opinion in Critical Care 2010; Volume 16, Issue 3, 211-5
3. Cureton et al. The heart of the matter: utility of ultrasound of cardiac activity during traumatic arrest. Journal of Trauma and Acute Care Surgery 2012; Volume 73, Issue 1, 102-10
4. Archinger G et al. Cardiac movement identified on prehospital echocardiography predicts outcome in cardiac arrest patients. Prehospital Emergency Care 2012; Volume 16, Issue 2, 251-5
5. Busch M. Portable ultrasound in pre-hospital emergencies: a feasibility study. Acta Anaesthesiologica Scand 2006; Volume 50, Issue 6, 754-8
6. Rooney et al. Pre-hospital assessment with ultrasound in emergencies: implementation in the field. World Journal of Emergency medicine 2016; Volume 7, Issue 2, 117-23
7. Salen et al. Does the presence or absence of sonographically identified cardiac activity predict resuscitation outcomes of cardiac arrest patients? American Journal of Emergency Medicine 2005; Volume 23, Issue 4, 459-62
8. Byhahn et al. Prehospital ultrasound detects pericardial tamponade in a pregnant victim of stabbing assault. Resuscitation 2008; Volume 76, Issue 1, 146-8
9. Ketelaars R et al. Prehospital Echocardiography During Resuscitation Impacts Treatment in a Physician-Staffed Helicopter Emergency Medical Service: an Observational Study. Prehospital Emergency Care 2018; Volume 22, 1-8
10. Blaivas M, Fox JC. Outcome in cardiac arrest patients found to have cardiac standstill on the bedside emergency department echocardiogram. Academic Emergency Medicine 2001; Volume 8, 616–21.
11. O’Dochartaigh D et al. Five-year Retrospective Review of Physician and Non-physician Performed Ultrasound in a Canadian Critical Care Helicopter Emergency Medical Service. Prehospital Emergency Care 2017; Volume 21, Issue 1, 24-31
12. Salen P et al. Can cardiac sonography and capnography be used independently and in combination to predict resuscitation outcomes? Academic Emergency Medicine 2001; Volume 8, 610-5
13. Gaspari et al. Emergency department point-of-care ultrasound in out-of-hospital and in-ED cardiac arrest. Resuscitation 2016; Volume 109, 33-39