Module 6 Flashcards
Module 6
Transesophageal Echocardiography
“What is the Best Advanced Hemodynamic Monitor?”
- Advanced blood pressure monitoring may be beneficial
- Beat-to-beat BP/stroke volume/SVV
- Easy to interpret, ability to monitor ABG
- Technologies like FloTrac, LiDCO, and PiCCO: These systems provide beat-to-beat blood _______(1), and _______(2), which are valuable for assessing fluid responsiveness in real-time.
- They are non-invasive or minimally invasive, easy to interpret, and some can offer insights into arterial blood _______(3) when integrated with blood sampling technologies.
- Risk and benefit should guide use of more advanced cardiovascular monitors
- Pulmonary artery catheter
- Swan-Ganz Catheter: The PAC has been the _______(4) for direct measurement of cardiac output, pulmonary artery pressures, and mixed venous oxygen _______(5). It’s especially beneficial in managing severe heart failure, complex cardiac conditions, and in settings where precise measurement of cardiac filling pressures and cardiac output is crucial for guiding therapy.
- However, its use comes with potential risks, such as arrhythmias, infection, and pulmonary artery rupture, and requires _______(6) for insertion and data interpretation.
- Pulmonary artery catheter
- Transesophageal Echo
- TEE provides dynamic, real-time images of the heart and great vessels. It is invaluable for diagnosing structural cardiac problems, assessing ventricular function, guiding complex cardiac surgeries, and managing critical care patients with hemodynamic instability.
- TEE can offer immediate feedback on the effectiveness of therapeutic interventions. Its limitations include the need for operator _______(7) and the semi-invasive nature of the procedure.
Answers:
1. blood pressure monitoring, stroke volume
2. stroke volume variation (SVV)
3. gases (ABG)
4. gold standard
5. saturation
6. specific expertise
7. expertise
- LV, RV, global and regional function
- TEE: _______(1)
- PAC: Indirect
- Left and right heart preload
- TEE: _______(2)
- PAC: Indirect
- CO and stroke volume
- TEE: _______(3)
- PAC: _______(4)
- Pulmonary artery pressure
- TEE: _______(5)
- PAC: _______(6)
- Anatomy
- TEE: _______(7)
- PAC: _______(8)
- Shunts
- TEE: _______(9)
- PAC: _______(10)
- Tamponade
- TEE: _______(11)
- PAC: Indirect
- Valve dysfunction
- TEE: _______(12)
- PAC: Indirect
- Observer dependent
- TEE: _______(13)
- PAC: _______(14)
- Complications
- TEE: _______(15)
- PAC: 1-5%
Answers:
1. +++
2. Direct
3. +
4. +++
5. ++
6. +++
7. +++
8. -
9. +++
10. +
11. +++
12. +++
13. Significant
14. Moderate
15. <1% (LESS)
Echocardiography
- Echocardiography is the application of ultrasound for imaging of the _______(1).
- Standard ultrasound techniques are used to image _______(2).
- Apart from 2-D, conventional echocardiography also employs M-mode and _______(3).
- Color Doppler is used to image flowing blood
- Red/Blue depending on if the blood is _______(4) or away from the probe
- Continuous wave Doppler and Pulsed wave Doppler are used to measure the velocity of flowing blood. Latest developments in the field of echocardiography include:
- Real time 3-D imaging
- _______(5) Doppler
- many specialized techniques
- American Society of Echocardiography (ASE) and the Society of Cardiovascular Anesthesiologists (SCA) publish position statements
______(a) Echocardiography
- Assessment of heart function and volume
- Evaluation of myocardial ischemia
- Assessment of valvular anatomy and function
- Evaluation of the aorta
- Detection of intracardiac defects
- Evaluation of pericardial effusions
- Detection of intracardiac air, clots or masses
______(b) Echocardiogram
- The usual echocardiogram is also known as a transthoracic echocardiogram, or TTE.
- In TTE, _______(6) is imaged from outside through the chest wall. The echocardiography probe is placed on the chest wall of the subject and images are obtained.
- This is a simple, highly accurate test.
- Some limitations: obesity, emphysema, surgical dressings, prosthetic valves and for examining cardiac structures not well visualized with TTE (left atrial appendage)
Answers:
1. heart
2. two-dimensional slices of the heart
3. Doppler
4. moving towards
5. tissue
a. Transesophageal
b. Transthoracic
6. heart
Transesophageal Echocardiogram
- Transesophageal echocardiogram, or TEE, requires insertion of a specialized endoscope containing an echocardiography transducer into the patient’s _______(1).
- TEE has the advantage of giving better images. This is because the transducer is closer to the heart. Some of the posterior structures of the heart are better imaged with TEE to include the aorta, the pulmonary artery, the valves of the heart, and the left _______(2).
- Most robust monitor of cardiac and hemodynamic function
- Direct assessment vs. indirect assessment
- Easily placed _______(3) as long as head is accessible
- Complex and unconventional interpretation
Ultrasound and Transesophageal Echo
- Echo passes sound waves through a medium or tissue
- Electrical energy is converted into brief pulses of sound
- Returning pulses of sound are converted into energy which generates an image
- Acoustic impedance of different tissues affects wave propagation and image
- Best image is generated when the beam is _______(4) to the structure
TEE and 2-D Ultrasound Imaging
- Image is scanned from the esophagus
- Near field objects are closest to the _______(5) (e.g., left atrium)
- Reflected signals are collated to produce a 2-D image of the structures
- Decreasing the depth _______(6) signal quality
- Manipulation of the TEE probe changes the sector and structures that are scanned
Answers:
1. esophagus
2. atrium
3. intrapop
4. perpendicular
5. esophagus
6. improves
Transesophageal Echo Imaging Maneuvers
- Advance or withdraw the _______(1)
- Turn the probe from side to side
- Rotate the sector (imaging plane) from 0-180 degrees (“omni”)
- Change the angle of the probe
- Forward (anteflex)
- Backward (retroflex)
- Left or _______(2)
Principles and Technology
- Ultrasound is _______(3) mechanical vibrations or pressure waves above a frequency the human ear can hear.
- Ultrasound uses a pulse-echo technique of imaging the body.
- Pulses are transmitted into _______(4) and give rise to echoes when they encounter interfaces/reflectors.
- Basically, the US probe sends sound waves into the body, and listens for those sound waves to come back. This information creates an image on the US screen.
- Fundamentals of the physics of ultrasound.
- Piezoelectric crystals are known to produce sound waves by vibrating when exposed to an electric current
- Some sound waves are reflected back to the crystals. In turn the crystals create an electric current. The ultrasound machine displays this electric current as an image on the screen.
- Within the esophagus, sound waves emitted by piezoelectric crystals are:
- Absorbed
- Scattered
- _______(5)
Technology
- When reflected by an organ (heart), the sound waves are received by the piezoelectric crystals housed within the TEE probe.
- These crystals then generate an electrical impulse that is processed, amplified and displayed as an _______(6).
- Frequency of the crystals in TEE probes ranges from ______(7) MHZ (megahertz).
Imaging Techniques
- Clinically, 4 primary ultrasound imaging techniques are used:
- M-Mode
- 2 dimensional (2-D) imaging
- Doppler exam
- 3 dimensional (3-D) imaging
Answers:
1. probe
2. right
3. high frequency
4. patient
5. Reflected
6. image
7. 3.7 to 7
M-mode Echocardiography
- High picture resolution with _______(1) images per second.
- One dimensional and produces a well-focused, narrow u/s beam (“icepick” view).
- This takes the 2-D image and graphs the image selected by the doppler line over time.
- This is a classic mode of 2-D transthoracic echocardiography to measure chamber sizes, valve area & _______(2).
2-D Echocardiography
- Two-dimensional echocardiography allows a plane of tissue (both depth and width) to be imaged in real _______(3).
- The anatomic relationships between various structures are easier to appreciate than with M-mode echocardiographic images.
- Standard views are used to evaluate the intra- and extra-cardiac structures, with triangular images (“a slice of pie” shaped).
6 Doppler Echocardiography
- Doppler imaging allows evaluation of blood flow patterns, direction, and _______(4).
- Permits documentation and quantification of valvular insufficiency or stenosis (etiology of regurgitation; adequacy of repairs) and cardiac shunts.
- Estimations of blood flow and cardiac output can also be made.
- Doppler echocardiography is based on detection of frequency changes (the ______(a)) occurring as ultrasound waves reflect off individual blood cells moving either away from or toward the transducer.
- Calculation of blood flow velocity is possible when the flow is parallel to the angle of the ultrasound _______(5).
Answers:
1. 1000
2. EF (ejection fraction)
3. time
4. velocity
a. Doppler shift
5. beam
Doppler Imaging
- 2-D imaging of structures does not reveal _______(1).
- Doppler ultrasound overcomes this limitation by providing direction and velocity of flow.
- To determine the velocity and direction of blood flow Doppler systems examine the change in frequency reflected from red blood cells.
Use of Doppler to Plot Velocity over Time
- Flow _______(2) and away from the transducer is plotted as velocity vs. time.
- High velocity flow across a valve signifies _______(3).
- Bidirectional flow may signify _______(4).
- _______(5) wave Doppler measures flow in a specific sample.
- Continuous wave Doppler measures flow along a line.
Color Doppler and Color Flow Mapping
- Doppler shifts and velocity in a plane are measured in several thousand samples.
- For each sample volume the average Doppler shift is encoded as a color.
- Direction and velocity of blood is depicted as:
- _______(6) towards the transducer
- Blue-_______(7) from the transducer
- “BART”
Answers:
1. blood flow
2. towards
3. stenosis
4. regurgitation
5. Pulse
6. Red
7. away
Principles of Echocardiography
- Acoustic ______(a) is a measure of the resistance to sound passing through a medium.
- Large differences in acoustic impedance between interfaces result in a _______(1) image.
- Small differences between interfaces result in a hypoechoic image.
- Amount of energy from returning echoes determine the color of the image (shades of gray)
- _______(2) (white) – large amount of energy returning from echoes
- i.e., pericardial/pleural effusion
- Hypoechoic (gray) – less energy from returning echoes
- i.e., muscle
- _______(3) (black) – areas without returning echoes; waves travel ______(b) without reflecting back
- i.e., blood/pericardial effusion
Intraoperative TEE
- Provides comprehensive evaluation of cardiac performance
- myocardium (systemic wall _______(4) abnormalities)
- Valves
- Are they opening?
- Have we blown a Mitral leaflet?
- hemodynamics (calculation of EF, ventricular preload, and measuring blood flow across chambers and valves)
Information Available by Basic TEE
- Left and right ______(6) function
- Heart wall ______(7)
- Heart chamber ______(8)
- ______(9) integrity
- ______(10) function and integrity
- _______(c)
- Heart ______(11)
- Pericardial effusion
Answers:
a. Impedance
1. hyperechoic
2. Hyperechoic
3. Anechoic
b. unimpeded
4. motion
c. Vegetation
6. ventricular
7. motion
8. volume
9. Vessel
10. Valve
11. tumors
TEE-knobology
1. On/Off
2. Quick keys
3. Gain
4. iScan (auto gain)
5. Depth adjustment
6. Zoom image
7. Lateral gain
8. Color imaging
9. 2-D reset
10. Freeze the image
11. Acquire an image
12. Review acquired images
13. Caliper (straight line)
14. Trace image (circular measurement for area)
15. Pulse Wave Doppler
16. Continuous Wave Doppler
(You don’t need to know the button Numbers on this image)
Probe/Equipment Considerations
- Bite block used, ______(a)
- Protects _______(1) and Probe
- Generous lubrication
- Jaw thrust utilized
- Insert to _______(2) cm
- ______(b)
- Contraindications include esophageal and gastric pathology
Complications
- Esophageal perforation
- Gastrointestinal hemorrhage
- Dental damage
- ______(c) damage (most common)
- Airway compromise
- Distraction from patient
- Because _______(3)
- Misinterpretation
Answers:
a. wheels unlocked
1. Teeth
2. 20-25
b. Unlock wheel to remove
c. Oral/lip
3. your eyes are on the TEE
Basic TEE Exam
- Benefits must outweigh the risks
- ______(1) Contraindications
- Previous esophagectomy
- Severe esophageal obstruction
- Esophageal perforation
- Ongoing esophageal hemorrhage
- ______(2) contraindications
- Esophageal diverticulum
- Varices
- How long after banding should you wait? She asks but didn’t answer
- Fistula
- Previous esophageal surgery
- Gastric surgery
- Mediastinal radiation
- Unexplained swallowing difficulties
- Anesthesia is induced; trachea secured
- Suction stomach as air can degrade the images
- Gently massage LUQ during suctioning
- Neck is extended
- Probe must be well lubricated
- Probe introduced
- Midline of the hypopharynx
- Transducer facing anteriorly
- May use a laryngoscope to assist with placement
- Control must be in the neutral or relaxed position
- Follow natural course of the esophagus
- Minimize risk of trauma
- Control must be in the neutral or relaxed position
- Basic applications include
- Detect abnormal ventricular filling or function
- Identify myocardial ischemia or infarction
- Large air emboli
- Severe valve dysfunction
- Large cardiac masses or thrombi
- Large pericardial effusions
- Major lesions of the great vessels
- Probe is advanced into the upper esophagus (UE), mid-esophagus (ME) and into the stomach (TG)
- Shaft can be manually rotated left or right
- Head of the probe can be anteflexed (anterior) or retroflexed (posterior)
- U/S beam can be rotated from 0 degrees (transverse plane) to 180 degrees in 1 degree increments
Answers:
1. Absolute
2. Relative
PLEASE STUDY THE FOLLOWING IMAGES AS CHATPGT CANNOT GENERATE NOTES OUR FROM THESE:
- Mid esophageal view
- Mid to Upper esophageal view
- Cont, Mid to Upper esophageal view
- Transgastric views
Transgastric long axis view is particularly helpful for evaluation of patients with ______(a) valves because this view generally produces less artifact.
- Aortic Views
- Cross-sectional views of the 11 views of the ASE and SCA basic PTE examination
Answers:
a. prosthetic
Detection of Myocardial Ischemia
- Can detect ischemia ______(a) ST changes are visible on the ECG
- Within moments of the onset of ischemia, affected areas of the myocardium cease to contract normally; i.e., “segmental wall motion _______(1).”
- Sudden, severe decrease in segmental contraction is likely due to ischemia
Limitations include
- Heart rotates markedly during _______(2)
- Uncoordinated contractions 2° BBB or LV pacing
- Surgical manipulation (_______(3)) or gauze packing
Additional causes of segmental wall motion abnormalities include
- Myocarditis
- Old myocardial infarction (thinning of the wall)
- Myocardial stunning
Complications w/ TEE
- ______(b) (most common)
- Dental damage
- Esophageal perforation
- Gastrointestinal hemorrhage
- Airway compromise
- Distraction from patient
- Misinterpretation
Answers:
a. before
1. abnormalities
2. systole
3. OPCABG (Off-Pump Coronary Artery Bypass Grafting)
b. Oral/lip injury
3-step TEE Examination (possible SATA?)
- Basal short axis exam (insert ______(a) cm)
- Aortic valve
- RV Inflow-Outflow
- Ascending aorta
- Four chamber exam (insert ______(b) cm)
- Four chamber
- Two chamber
- ME Long axis
- ME Descend thoracic aorta
- Transgastric exam (insert ______(c) cm)
- _______(1) LV/RV
Answers:
a. 20-25
b. 25-30
c. 35-40
1. Midpapillary
Midesophageal aortic valve short axis (ME AV SAX)
- Ideal for detection of _______(1)
- Evaluation of aortic insufficiency
- Examine the interatrial septum for a patent foramen ovale (PFO)
- The familiar “______(2)” sign denotes the 3 cusps of the aortic valve
Answers:
1. aortic stenosis
2. Mercedes Benz
Midesophageal aortic valve long axis (ME AV LAX)
- What do the PL and AL abbreviations represent? LVOT?
- PL: _______(1)
- AL: _______(2)
- LVOT: _______(3)
- Detection of ascending aortic abnormalities
- including ______(a)
- Color Flow Doppler for assessment of AV competence (AI)
- AV masses or vegetations
- LV outflow tract pathology
- Calcification or dissection flaps in the proximal AA
Answers:
1. Pleural Leaflet
2. Aortic Leaflet
3. Left Ventricular Outflow Tract
a. type I aortic dissection
