Cardiac Ultrasound in Emergency Medicine Anthony J. Weekes MD, RDMS Sarah A. Stahmer MD For the SAEM US Interest Group

Primary Indications Thoraco-abdominal trauma Pulseless Electrical Activity Unexplained hypotension Suspicion of pericardial effusion/tamponade

Secondary Indications Acute Cardiac Ischemia Pericardiocentesis External pacer capture Transvenous pacer placement

Main Clinical Questions What is the overall cardiac wall motion? Is there a pericardial effusion?

Cardiac 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 views Parasternal Subcostal Apical

Wall Motion Normal Hyperkinetic Akinetic Dyskinetic: may fail to contract, bulges outward at systole Hypokinetic

Orientation Subcostal or subxiphoid view Best all around imaging window Good for identification of: Circumferential pericardial effusion Overall wall motion Easy to obtain – liver is the acoustic window\

Subcostal View Most practical in trauma setting Away from airway and neck/chest procedures

Subcostal View Liver as acoustic window Alternative to apical 4 chamber view

Subcostal View

Subcostal View

Subcostal View Angle probe right to see IVC Response of IVC to sniff indicates central venous pressure No collapse Tamponade CHF PE Pneumothorax

Parasternal Views Next best imaging window Good for imaging LV Comparing chamber sizes Localized effusions Differentiating pericardial from pleural effusions

Parasternal Long Axis Near sternum 3rd or 4th left intercostal space Marker 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 Axis

Parasternal Long Axis View

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 View

Parasternal Short Axis

Apical View Difficult view to obtain Allows comparison of ventricular chamber size Good window to assess septal/wall motion abnormalities

Apical 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 view Marker pointed to the floor Similar to parasternal view but apex well visualized Angle beam superiorly for 5 chamber view

Apical 4 chamber view

Apical 2 chamber view Patient in left lateral decubitus position Probe placed at PMI Probe marker at 3 o’clock 2 chamber view

Apical 2 chamber view Good look at inferior and anterior walls

Apical 2 chamber view From apical 4, rotate probe 90° counterclockwise Good view for long view of left sided chambers and mitral valve

Abnormal findings Pericardial Effusion

Case 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 140 PE: Neck veins are distended Chest: Clear, muffled heart sounds Bedside sonography was performed

Echo free space around the heart Pericardial effusion Pleural effusion Epicardial fat (posterior and/or anterior) Less common causes: Aortic aneurysm Pericardial cyst Dilated pulmonary artery

Size of the Pericardial Effusion Not Precise Small: confined to posterior space, < 0.5cm Moderate: anterior and posterior, 0.5-2cm (diastole) Large: > 2cm

Pericardial Fluid: Subcostal

Clinical features of Pericardial effusion Pericardial fluid accumulation may be clinically silent Symptoms are due to: mechanical compression of adjacent structures Increased intrapericardial pressure

Pericardial Effusion:Asymptomatic Up to 40% of pregnant women Chronic hemodialysis patients one study showed 11% incidence of pericardial effusion AIDS CHF Hypoproteinemic states

Symptoms of Pericardial Effusion Chest discomfort (most common) Large effusions: Dyspnea Cough Fatigue Hiccups Hoarseness Nausea and abdominal fullness

Cardiac Tamponade Increased intracardiac pressures Limitation of ventricular diastolic filling Reduction of stroke volume and cardiac output

Ventricular collapse in diastole

Tamponade Perefftamponade

Hypotension

Abnormal findings Is the cause of hypotension cardiac in etiology? Is it due to a pericardial effusion? Is is due to pump failure?

Unexplained Hypotension Cardiogenic shock Poor LV contractility Hypovolemia Hyperdynamic ventricules Right ventricular infarct/large pulmonary embolism Marked RV dilitation/hypokinesis Tamponade RV diastolic collapse

Cardiogenic shock Dilated left ventricle Hypocontractile walls Chf avi

Hypovolemia Small chamber filling size Aggressive wall motion Flat IVC or exaggerated collapse with deep inspiration

Massive PE or RV infarct Dilated Right ventricle RV hypokinesis Normal Left ventricle function Stiff IVC

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: clear Ext: No edema Bedside sonography was performed

PE

Chest pain then code 55 yo male suffered witnessed Vfib arrest in the ED ALS protocol - restoration of perfusing rhythm Persistant hypotension ED ECHO was performed

R sided leads

Non Traumatic Resuscitation

Direct Visualization Is there effective myocardial contractility? Asystole Myocardial “twitch” Hypokinesis Normal Is there a pericardial effusion?

ECHO 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

ECHO in PEA RV dilatation Profound hypokinesis Asystole Hypoxic?? – Likely PE ECG – IMI with RV infarct? Profound hypokinesis Inotropic support Asystole Follow ACLS protocols (for now) Early data suggesting poor prognosis

ECHO in PEA False positive cardiac motion Transthoracic pacemaker Positive pressure ventilation

Case 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 contractions

Optimizing Performance Assessing capture by transthoracic pacemaker Pericardiocentesis Transvenous pacemaker placement

Optimizing Performance Assessment of capture by transthoracic pacemaker Ettin D et al: Using ultrasound to determine external pacer capture JEM 1999

Case 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? Why is she hypotensive? Volume loss Pump failure ?Ruptured AAA Pump failure Bedside sonography was performed while we were waiting for the “labs”

Increase HR with PM “on”

What did this tell us? Normal wall motion No pericardial/pleural effusion Good capture with the transthoracic PM

Asystole w/ Transthoracic PM Asystole epm.avi

Optimizing performance Pericardiocentesis Standard of care by cardiology/CT surgery to use ECHO to guide aspiration

US Guided- Pericardiocentesis 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 effusion

Technique

Optimizing performance Placement of transvenous pacemaker Aguilera P et al: Emergency transvenous cardiac pacing placement using ultrasound guidance. Ann Emerg Med 2000

Untimely end 30 yo brought in after he “fell out” Ashen m with no spontaneous respirations VS: No pulse, agonal rhythm on monitor Intubated/CPR Transvenous pacemaker placed, no capture. ECHO showed

PM placement

Penetrating Chest Trauma

Penetrating 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 Injury Emergency 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 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

Penetrating Cardiac Trauma 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 chest SAEM Pericardial effusion

Penetrating Cardiac Trauma 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 Problems Subcutaneous air Pneumopericardium Mechanical ventilation Scanning limited by: Pain/tenderness Spinal immobilization Ongoing procedures

Technical Problems Narrow intercostal spaces Obesity Muscular chest COPD Calcified rib cartilages Abdominal distention

Sonographic Pitfalls Pericardial versus pleural fluid Pericardial clot Pericardial fat

Pericardial or Pleural Fluid Left 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 fluid Pleural perica

Pleural effusion

Blunt Cardiac Trauma Cardiac contusion Cardiac rupture Valvular disruption Aortic disruption/dissection

Blunt Cardiac Trauma Pericardial effusion Assess for wall motion abnormality RV dyskinesis (takes the first hit) Assess thoracic aorta: Hematoma Intimal flap Abnormal contour Valvular dysfunction or septal rupture

Cardiac Contusion Akinetic anterior RV wall Small pericardial effusion Diminished ejection fraction

RV Contusion

Blunt Cardiac Trauma Assess thoracic aorta Hematoma Intimal flap Abnormal contour Requires TEE and expertise! Valvular dysfunction or septal rupture Requires expertise beyond our scope

Summary 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