Transthoracic Echocardiography:

An essential tool for the obstetric

anaesthetist?

Brendan Carvalho MBBCh, FRCA

Department of Anesthesiology

Stanford University, California

Focused TTEStethoscope of the 21st Century

Vignon P. Anesth Analg 2012;105(5):999-103

Russell C. Intensive Care Med 2007; 33:1106

“It is time to demystify echocardiography, and to move it

beyond the confines of cardiology and cardiac anesthesia

into the everyday management of the acutely ill patient”

History of Ultrasound and

Echocardiography

• 1790 Spallanzani: Bats• 1826 Colladon: Sonography underwater bell• 1842 Christian Doppler: Doppler effect/shift• 1931 Mulhauser: Patent ultrasonic waves to

detect flaws in solids

• Late 1940s Ludwig, Wild: Ultrasound applied to human body for medical purposes

• 1962: Contact B-mode scanner • Late 1960s: Doppler ultrasound

B Mode (2D)

M Mode Color DopplerPulsed/Continuous

Wave Doppler

Use of Echocardiography

• Emergency Department 1,2

• Critical Care / Intensive Care 3,4

Class 1 recommendation: US, UK and European Guidelines

• Evaluation of hypotension, shock or hemodynamic instability• Blunt or penetrating chest trauma or suspected aortic injury

“Fundamental tool to expedite diagnostic evaluation at the bedside and initiate

emergent treatment and triage decisions by the emergency physician”

American Society of Echocardiography + American College of Emergency Physicians

• Preoperative and intraoperative setting 5,6

1. Labovitz AJ et al. J Am Soc Echocardiogr 2010;23:1225-30

2. Scalea TM. FAST: J Trauma 1999; 46:466–472

3. Jensen MB. Eur J Anaesthesiol. 2004;21(9):700-7. www.fate-protocol.com

4. Beaulieu Y. Crit Care Med 2007; 35[Suppl.]:S235–S249

5. Cowie B. J Cardiothoracic and Vascular Anesthesia 2009; 23, (4):450-456

6. Canty DJ. Anaesthesia 2012; 67, 618-625

Examination Protocols

• Focused Assessment with Sonography in Trauma (FAST)

• Focus Assessed Transthoracic Echocardiography (FATE)

• Rapid Ultrasound in SHock (RUSH)• Focused cardiac ultrasound (FOCUS) • Bedside limited echocardiography by the emergency

physician (BLEEP)

• Hemodynamic echocardiographic assessment in real time (HART)

• Bedside, inexpensive, portable• Therapeutic and diagnostic• Bedside Lung Ultrasound in Emergency

(BLUE) protocol

• Detected lung pathologies:• Pneumothorax • Pulmonary edema• Pleural effusions and hemothorax• ARDS, Pneumonia, PE

Turner JP. Emerg Med Clin N Am 2012; 30: 451–473

Lichtenstein DA. The BLUE protocol. Chest 2008;134(1):117–25

• Examine unexplained hypotension• Dyspnea (cardiac or pulmonary)• Aid resuscitation during hemorrhage• Preeclampsia• Diagnostic:

• Peripartum cardiomyopathy• Pulmonary or amniotic embolus

• PEA arrestDennis AT. Int J Obstet Anesth 2011;20:160–8

Dennis AT. Anesth Analg 2012;105(5):1033-7

Rapid Obstetric Screening

Echocardiography (ROSE)

• Acceptable and applicable• Bedside test in left lateral position• Comfortable and concise examination

(parasternal and apical views)

• Diagnosis and response to therapy (contractility and volume status)

• Embolism (air, blood, amniotic fluid) Right heart function

• Fetal heart rate assessmentDennis AT. Int J Obstet Anesth 2011;20:160–8

Dennis AT. Anesth Analg 2012;105(5):1033-7

Linear (5-15 MHz)

Curved array (1-5 MHz)

Phased array (1-5 MHz)

• Parasternal long and short axis• Apical 4-chamber and 5-chamber• Sub-xiphoid

Aorta (5-chamber)

Focused Echocardiographic Evaluation

in Life Support (FEEL)

• Confirm cardiac arrest• Effectiveness of chest compressions• Detect ROSC• Diagnosis:

• Myocardial insufficiency• Hypovolemia• Pulmonary embolus• Pericardial tamponade

Breitkreutz R. Crit Care Med 2007; 35[Suppl.]:S150–S161

Oren-Grinberg. Anesth Analg 2012;115(5):1038-41

IVC

Measured% Collapse CVP

< 1.5cm >50% 0-5

1.5-2.5cm >50% 5-10

1.5-2.5cm 2.5 cmLittle

phasicity15-20

Kircher BJ. Am J Cardiology 1990; 66(4):493-96

Hypovolemia

Cardiomyopathy

Qualitative vs. Quantitative

Evaluation• Qualitative evaluation distinguish LV function,

SVC collapsibility, dilated RV 1

• Visual vs. measured estimation of RV size and function inaccurate, inter-observer variability 2

1. Vieillard-Baron A. Intensive Care Med 2006;32:1547–1552

2. Ling LF. J Am Soc Echocardiogr 2012; 25:709-13

Normal

Moderate Severe

ROSE MeasurementsDennis AT. Int J Obstet Anesth 2011;20:160–8 Supplementary Data

Cardiac output = (LVOTd/2) 2× π× VTI × HR

Fractional area change = (LVEDA–LVESA) / LVEDA x 100

Fractional shortening = (LVEDD–LVESD)/LVEDD x 100

Mitral valve E/A ratio

Septal eʹ/ aʹ ratio

N >25%

Pulmonary Embolus

Kircher BJ. Am J Cardiology 1990;66(4):493-96

Pre-Eclampsia

• Untreated pre-eclampsia 1

• ↑ Cardiac output and Vasoconstriction

• ↑ Inotropy and ↓ Diastolic function

• Treated severe pre-eclampsia 2

• Systolic function preserved

• Diastolic function reduced

Large variability in hemodynamics

1. Dennis AT. Anaesthesia 2012; 67: 1105-1118

2. Dennis AT. Anaesthesia 2014; 69; 436-444

• No or limited equipment• Inadequate skills • Quality assurance• Culture of suspicion• Limited outcome data

CompetencyCourses,

Oxorn D. Anesth Analg 2012;105(5):1004-6

Level 1: Qualitative analysis

Wall motion and thickness

Chamber size

Right and left systolic

function

Pericardial assessNational and Institutional

Workshops

Courses

“Shadow” an ECHO tech

or cardiologist

Quality Assurance and Outcome

Recording

• Ongoing education and training• Practical experience

• Supervised scanning (50 cases)• Unsupervised with expert reviews (50 cases) • Ongoing studies (100 cases)

• Report and document examination• Quality assurance from expert practitioner• Outcome recording

ANZCA PS46 2013

Dennis AT. Int J Obstet Anesth 2011;20:160–8

Summary

• Numerous indications for transthoracic

echocardiography in obstetric anesthesia

• Focused TTE integral tool: unexplained

hypotension, dyspnea, resuscitation

• Clinical outcome data is still needed

• Valuable skill for anesthesiologists