cardiac ultrasound in emergency medicine anthony j. weekes md, rdms sarah a. stahmer md for the saem...

Cardiac Ultrasound in Cardiac Ultrasound in Emergency MedicineEmergency Medicine

Anthony J. Weekes MD, RDMSSarah A. Stahmer MD

For the SAEM US Interest Group

Primary IndicationsPrimary Indications

Thoraco-abdominal trauma

Pulseless Electrical Activity

Unexplained hypotension

Suspicion of pericardial

effusion/tamponade

Secondary IndicationsSecondary Indications

Acute Cardiac Ischemia

Pericardiocentesis

External pacer capture

Transvenous pacer placement

Main Clinical QuestionsMain Clinical Questions

What is the overall cardiac wall motion?

Is there a pericardial effusion?

Cardiac probe selectionCardiac probe selection

Small round footprint for scan between ribs

2.5 MHz: above average sized patient

3.5 MHz: average sized patient

5.0 MHz: below average sized patient or child

Main cardiac viewsMain cardiac views

Parasternal Subcostal Apical

Wall MotionWall Motion

NormalHyperkineticAkineticDyskinetic: may fail

to contract, bulges outward at systole

Hypokinetic

OrientationOrientation

Subcostal or subxiphoid viewBest all around imaging windowGood for identification of:

– Circumferential pericardial effusion– Overall wall motion

Easy to obtain – liver is the acoustic window\

Subcostal ViewSubcostal View

Most practical in trauma setting

Away from airway and neck/chest procedures


Liver as acoustic window

Alternative to apical 4 chamber view


Angle probe right to see IVC

Response of IVC to sniff indicates central venous pressure

No collapse– Tamponade– CHF– PE– Pneumothorax

Parasternal ViewsParasternal Views

Next best imaging windowGood for imaging LVComparing chamber sizesLocalized effusionsDifferentiating pericardial from pleural

effusions

Parasternal Long AxisParasternal Long Axis

Near sternum3rd or 4th left intercostal spaceMarker pointed to patient’s right

shoulder (or left hip if screen is not reversed for cardiac imaging)

Rotate enough to elongate cardiac chambers

Parasternal Long AxisParasternal Long Axis

Parasternal Long Axis ViewParasternal Long Axis View

Parasternal Short Axis Parasternal Short Axis

Obtained by 90° clockwise rotation of the probe towards the left shoulder (or right hip)

Sweep the beam from the base of the heart to the apex for different cross sectional views

Parasternal Short Axis ViewParasternal Short Axis View

Parasternal Short AxisParasternal Short Axis

Apical ViewApical View

Difficult view to obtainAllows comparison of ventricular

chamber sizeGood window to assess septal/wall

motion abnormalities

Apical ViewsApical Views

Patient in left lateral decubitus position

Probe placed at PMI

Probe marker at 6 o’clock (or right shoulder)

4 chamber view

Apical 4 chamber viewApical 4 chamber view Marker pointed to

the floor Similar to

parasternal view but apex well visualized

Angle beam superiorly for 5 chamber view

Apical 4 chamber viewApical 4 chamber view


Patient in left lateral decubitus position

Probe placed at PMI

Probe marker at 3 o’clock

2 chamber view

Apical 2 chamber viewApical 2 chamber view Good look at inferior and anterior walls


From apical 4, rotate probe 90° counterclockwise

Good view for long view of left sided chambers and mitral valve

Abnormal findingsAbnormal findings

Pericardial Effusion

Case PresentationCase Presentation

45 year old male presents with SOB and dizziness for 2 days. He has a long smoking history, and has complained of a non-productive cough for “weeks”

Initial VS are BP 88/palp, HR 140PE: Neck veins are distendedChest: Clear, muffled heart soundsBedside sonography was performed

Echo free space around the heartEcho free space around the heart

Pericardial effusionPleural effusionEpicardial fat (posterior and/or

anterior)Less common causes:

– Aortic aneurysm– Pericardial cyst– Dilated pulmonary artery

Size of the Pericardial Size of the Pericardial EffusionEffusion

Not PreciseSmall: confined to posterior space,

< 0.5cmModerate: anterior and posterior,

0.5-2cm (diastole)Large: > 2cm

Pericardial Fluid: Subcostal Pericardial Fluid: Subcostal

Clinical features of Clinical features of Pericardial effusionPericardial effusion

Pericardial fluid accumulation may be clinically silent

Symptoms are due to:– mechanical compression of adjacent

structures– Increased intrapericardial pressure

Pericardial Pericardial Effusion:AsymptomaticEffusion:Asymptomatic

Up to 40% of pregnant womenChronic hemodialysis patients

– one study showed 11% incidence of pericardial effusion

AIDSCHFHypoproteinemic states

Symptoms of Pericardial Symptoms of Pericardial EffusionEffusion

Chest discomfort (most common)Large effusions:

– Dyspnea– Cough– Fatigue– Hiccups– Hoarseness– Nausea and abdominal fullness

Cardiac TamponadeCardiac Tamponade

Increased intracardiac pressures

Limitation of ventricular diastolic filling

Reduction of stroke volume and cardiac output

Ventricular collapse in Ventricular collapse in diastolediastole

TamponadeTamponade

HypotensionHypotension

Abnormal findingsAbnormal findings

Is the cause of hypotension cardiac in

etiology?

Is it due to a pericardial effusion?

Is is due to pump failure?

Unexplained HypotensionUnexplained Hypotension

Cardiogenic shock – Poor LV contractility

Hypovolemia– Hyperdynamic ventricules

Right ventricular infarct/large pulmonary embolism– Marked RV dilitation/hypokinesis

Tamponade– RV diastolic collapse

Cardiogenic shockCardiogenic shock

Dilated left ventricle

Hypocontractile walls

HypovolemiaHypovolemia

Small chamber filling size

Aggressive wall motion

Flat IVC or exaggerated collapse

with deep inspiration

Massive PE or RV infarctMassive PE or RV infarct

Dilated Right ventricle

RV hypokinesis Normal Left

ventricle function Stiff IVC

Case presentation ? overdose Case presentation ? overdose

27 yo f brought in with “passing out” after night of heavy drinking.

Complaining of inability to breathe!PE: Obese f BP 88/60 HR 123 Ox

78% Chest: clearExt: No edemaBedside sonography was performed

Chest pain then codeChest pain then code

55 yo male suffered witnessed Vfib arrest in the ED

ALS protocol - restoration of perfusing rhythm

Persistant hypotensionED ECHO was performed

R sided leads

Non Traumatic Non Traumatic ResuscitationResuscitation

Direct VisualizationDirect VisualizationIs there effective myocardial

contractility?– Asystole– Myocardial “twitch”– Hypokinesis– Normal

Is there a pericardial effusion?

ECHO in PEAECHO in PEA

Perform ECHO during “quick look” and in pulse checks

Change management based on “positive” findings

Pericardial tamponade– Pericardiocentesis

Hyperdynamic cardiac wall motion– Volume resuscitate


RV dilatation– Hypoxic?? – Likely PE– ECG – IMI with RV infarct?

Profound hypokinesis– Inotropic support

Asystole– Follow ACLS protocols (for now)– Early data suggesting poor prognosis


False positive cardiac motion

– Transthoracic pacemaker

– Positive pressure ventilation

Case presentationCase presentation

Morbidly obese female with severe asthma Intubated for respiratory failure Subcutaneous emphysema developed Bilateral chest tubes placed Persistent hypotension at 90/palp Dependent mottling noted ECHO was performed

Ineffective cardiac Ineffective cardiac contractionscontractions

Optimizing PerformanceOptimizing Performance

Assessing capture by transthoracic pacemaker

Pericardiocentesis

Transvenous pacemaker placement

Optimizing PerformanceOptimizing Performance

Assessment of capture by transthoracic pacemaker

Ettin D et al: Using ultrasound to determine external pacer capture JEM 1999

Case PresentationCase Presentation

70 yo f collapsed in lobby. She was brought into the ED apneic, hypotensive. She was quickly intubated and volume resuscitation begun.

VS: BP 80/50 HR 50 Afebrile Physical exam : Thin, minimally responsive f.

Clear lungs, nl heart sounds, abdomen slightly distended with decreased bowel sounds. No HSM, ? Pelvic mass

ECG: SB, LVH, no active ischemia

Clinical questions?Clinical questions?

Why is she hypotensive?Volume loss

?Ruptured AAAPump failureBedside sonography was performed

while we were waiting for the “labs”

Increase HR with PM “on”Increase HR with PM “on”

What did this tell us?What did this tell us?

Normal wall motion

No pericardial/pleural effusion

Good capture with the transthoracic PM

Asystole w/ Transthoracic PMAsystole w/ Transthoracic PM

Optimizing performance Optimizing performance

Pericardiocentesis– Standard of care by cardiology/CT surgery

to use ECHO to guide aspiration

US Guided- US Guided- PericardiocentesisPericardiocentesis Subcostal approach

– Traditional approach– Blind– Increased risk of injury to liver, heart

Echo guided– Left parasternal preferred for needle entry

or…– Largest area of fluid collection adjacent to

the chest wall

Large pericardial effusionLarge pericardial effusion

TechniqueTechnique

Optimizing performanceOptimizing performance

Placement of transvenous pacemakerAguilera P et al: Emergency

transvenous cardiac pacing placement using ultrasound guidance. Ann Emerg Med 2000

Untimely end Untimely end

30 yo brought in after he “fell out”Ashen m with no spontaneous

respirationsVS: No pulse, agonal rhythm on monitorIntubated/CPRTransvenous pacemaker placed, no

capture.ECHO showed

Penetrating Chest TraumaPenetrating Chest Trauma

Penetrating Cardiac TraumaPenetrating Cardiac Trauma

Physician’s ability to determine whether there is a hemodynamically significant effusion is poor

Beck’s Triad – Dependent on patient cardiovascular status– Findings are often late

Determinants of hemodynamic compromise– Size of the effusion– Rate of formation

Penetrating Cardiac InjuryPenetrating Cardiac InjuryEmergency department

echocardiography improves outcome in penetrating cardiac injury.

Plummer D et al. Ann Emerg Med. 1992

28 had ED echo c/w 21 without ED echo Survival: 100% in echo, 57.1% in nonecho Time to Dx: 15 min echo, 42 min nonecho

Penetrating Cardiac InjuryPenetrating Cardiac Injury

The role of ultrasound in patients with possible penetrating cardiac wounds: a prospective multicenter study.

Rozycki GS: J Trauma. 1999

Pericardial scans performed in 261 patients Sensitivity 100%, specificity 96.9% PPV: 81% NPV:100% Time interval BUS to OR: 12.1 +/- 5.9 min

Emergency Department Echocardiography Improves Outcome in Penetrating Cardiac Injury

Plummer D, et al. Ann Emerg Med 21:709-712, 1992.

“Since the introduction of immediate ED two-dimensional echocardiography, the time to diagnosis of penetrating cardiac injury has decreased and both the survival rate and neurologic outcome of survivors has improved.”


Stab wound to the chestStab wound to the chest

Echocardiographic signs of rising intrapericardial pressure– Collapse of RV free walls– Dilated IVC and hepatic veins

Goal: Early detection of pericardial effusion– Develops suddenly or discretely– May exist before clinical signs develop

Salvage rates better if detected before hypotension develops


Technical ProblemsTechnical Problems

Subcutaneous airPneumopericardiumMechanical ventilation Scanning limited by:

– Pain/tenderness– Spinal immobilization– Ongoing procedures

Technical Problems Technical Problems

Narrow intercostal spacesObesityMuscular chest COPDCalcified rib cartilagesAbdominal distention

Sonographic PitfallsSonographic Pitfalls

Pericardial versus pleural fluid

Pericardial clot

Pericardial fat

Pericardial or Pleural FluidPericardial or Pleural FluidLeft parasternal long axis:

– Pericardial fluid does not extend posterior to descending aorta or left atrium

Subcostal: – No pleural reflection between liver and R

sided chambers– A pleural effusion will not extend between

to RV free wall and the liver

Pleural and Pericardial fluidPleural and Pericardial fluid

Pleural effusionPleural effusion

Blunt Cardiac TraumaBlunt Cardiac Trauma

Cardiac contusion

Cardiac rupture

Valvular disruption

Aortic disruption/dissection


Pericardial effusionAssess for wall motion abnormality

– RV dyskinesis (takes the first hit)Assess thoracic aorta:

– Hematoma– Intimal flap– Abnormal contour

Valvular dysfunction or septal rupture

Cardiac ContusionCardiac Contusion

Akinetic anterior RV wall

Small pericardial effusion

Diminished ejection fraction

RV ContusionRV Contusion


Assess thoracic aorta– Hematoma– Intimal flap– Abnormal contour– Requires TEE and expertise!

Valvular dysfunction or septal rupture– Requires expertise beyond our scope

SummarySummary

Bedside ECHO can help assess:– Overall cardiac wall motion– Identify clinically significant pericardial effusions

Useful in the assessment of the patient with:– Unexplained hypotension– Dyspnea– Thoracic trauma

cardiac ultrasound in emergency medicine anthony j. weekes md, rdms sarah a. stahmer md for the saem...

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