ECC VPOCUS Flashcards
Veterinary Point-of-Care Ultrasound (VPOCUS)
- what is it? what do we use it for?
Extension of physical examination, modern visual stethoscope
- Initial screening test: answer specific (Y/N) clinical questions
> direct stabilization & resuscitation efforts
> guide diagnostic plans & clinical course
> monitor progression or resolution
Veterinary Point-of-Care Ultrasound (VPOCUS) does not replace what?
DO NOT replace clinical assessment, thoracic auscultation, formal diagnostic imaging (x-rays, ultrasound, CT, echocardiography)
Advantages of VPOCUS
- Non-invasive, safe
- Bedside, portable, widely available
- Minimal restraint (unstable patients)
- Rapid, early detection
- expedites timely diagnosis of many conditions
- Inexpensive, serial examinations
- Radiation sparing
- Achievable proficiency, easily-mastered skills
- No clipping, alcohol sufficient
avoid what position for VPOCUS
dorsal recumbency
what dictates stabilization & order of POCUS
Triage Exam
what colour are fluids, soft tissue, air, bone, stones, on US?
anechoic / black = some fluid
hypoechoic / isoechoic / shades of grey
= soft tissue, some fluid
hyperechoic / whites = air, bone, stones, fibrous tissue
()
Air looks like striped lines
fluid looks black
soft tissue is grey
fibrous tissue is white
stones/bones are white with defined border
properties of linear array probe
- frequency, depth, resolution
- higher frequency
- less penetration (↓ depth)
- better resolution (details)
properties of curvilinear array probe
- frequency, depth, resolution
Curvilinear (microconvex) array
- lower frequency
- greater penetration (↑ depth)
- poorer resolution (details)
how do we keep out bearings with US?
reference mark on probe,
- should point to head if longitudinal
- points to patient’s right if transverse
what is FAST and what is it used for?
- Focused Assessment with Sonography for Trauma, Triage, Tracking
- 2004 veterinary: free fluid (trauma) > intraabdominal, intrathoracic lesions (beyond trauma) > trending (monitoring)
what is included in global FAST
- Abdominal FAST® +/- specific target organs
- Thoracic FAST®
- Vet BLUE®
- Focused ECHO
Abdominal FAST® or POCUS - what is included?
- Original AFAST: 4 sites
> Diaphragmaticohepatic (DH) - Subxiphoid
> Splenorenal (SR)
> Cystocolic (CC)
> Hepatorenal (HR) - 5-point standardized AFAST: 5 sites
> NEW: 5th umbilical view - Free fluid: Y/N
- Specific target organs of interest
Abdominal fluid scores (AFS)
- what do they mean?
- # of FAST positive sites: 0-4> if ≤ 5mm (cat) or ≤ 1cm (dog): give score of 0.5
positive sites: origin of injury? - Degree of hemorrhage, need for blood transfusions
> AFS 3-4: big bleeder
> AFS 1-2: small bleeder - Serial exams q 4-6 hours: monitor ongoing/resolution
> n=27, 17% became positive on serial AFAST®
> time, fluid resuscitation
Thoracic FAST® & Evolution of TFAST®
- what is our scanning positions? what views do we take? what are we assessing?
- Scanning position: standing or sternal*
- Original TFAST: 4 views
> Chest tube sites (CTS) 7th to 9th ICS
> Pericardial sites (PCS) - 5-point standardized TFAST: 5 views
> DH site: window into pleural & pericardial spaces
> Dogs: heart rests on diaphragm - Free fluid: Y/N
- Pneumothorax: Y/N
Vet BLUE® or PLUS - what are they? what are they for?
- Veterinary Bedside Lung Ultrasound Examination
> more extensive regionally-based lung scan
> wet lung (B-lines) vs. dry lung (glide sign and A-lines) - Pleural space & Lung UltraSound
- Screening evaluation: respiratory distressed / respiratory-compromised
- Pattern-based approach, categorize into probable causes:
> upper airway vs. lower airway
> heart failure vs. lung disease vs. respiratory look-a-likes
Vet BLUE® Protocol
- 8 sites:
- Caudodorsal lung lobe region (CdLL)
- Perihilar lung lobe region (PhLL)
- Middle lung lobe region (MdLL)
- Cranial lung lobe region (CrLL)
Lung Surface Artifacts
- normal? abnormal?
Normal:
Gator/bat sign
P-P line
A-lines
Z-lines
Glide sign
Seashore sign
Curtain sign
()
Abnormal:
Barcode sign
Lung point
B-lines
Shred sign
Tissue sign
Nodule sign
Free fluid (quad sign)
Gator/Bat Sign
- what is it?
- Normal: intercostal orientation
P-P (Pulmonary-Pleural) Line
- what is it?
- Hyperechoic linear continuity between ribs
- Normal: parietal & visceral pleura
A-Lines
- what are they?
- Equidistant hyperechoic parallel lines distal to P-P line
- Normal: air reverberation artifacts
Glide Sign
- what is it? good or bad? how to enhance?
- Normal: Glide is Good
- Real-time shimmering appearance at P-P line
- Parietal (thoracic wall) & visceral (lung) pleura apposition
- To-and-fro sliding motion at different speed & direction
- Absent = pneumothorax
()
3 tricks to enhance:
1. reduce gain (brightness)
2. tilt probe to scan at an angle
3. slide probe over a rib
Seashore vs. Barcode Sign
- what does it mean?
pneumothorax
B-Lines (a.k.a. Lung Rockets, Comet Tails)
- what are they? what do they mean?
- Laser-like hyperechoic lines extending from P-P line to the far field
- Obliterates A-lines, oscillate (bold arrows) with respiration
() - Wet lung, alveolar-interstitial syndrome = non-specific, ↓ aeration in lungs
- Patient signalment, history, PE findings, regional lesion distribution pattern:
- Cardiogenic pulmonary edema
- Non-cardiogenic pulmonary edema
- Pulmonary contusions / hemorrhage
- Pneumonia - Atelectasis
- Fibrosis, etc.
() - Rule out pneumothorax
The Vet BLUE® B-Line Scoring System
- Normal = infrequent 1-3 B-lines at single site
- ↑↑B-lines∝↑↑severity
() - Sentinels:
- wet lung (interstitial syndrome)
- alveolar flooding (alveolar syndrome) - lung consolidation (shred, tissue signs)
Shred Sign
- what does this mean?
- Lung consolidation with aeration
- Sig. deviation from normal linear continuity of hyperechoic P-P line
- Hypoechoic, echo-poor tissue with rough-jagged margins (shredded)
Tissue Sign
- what does this mean?
- Lung consolidation with no aeration
- Ultrasonographic appearance of lung similar to tissue
- Tissue (lung) hepatization = looks like liver
Nodule Sign
- what does this look like?
- Focal, well-marginated, circumscribe hypoechoic structure(s)
- Surrounded distally by air-filled lung
Free Fluid (Quad Sign)
- what does it look like?
Ranges in echogenicity
- anechoic (black) > moderate echogenicity (shades of grey)
- degree of viscosity & cellularity
Limitations of Vet BLUE® or PLUS
- US cannot adequately image through aerated lung (air)
- Lung surface pathologies: 3 mm
> detect lesions extended to lung periphery
> unable to detect centrally (deeper) located pulmonary lesions - DO NOT replace formal diagnostic imaging (x-rays, CT scan)
() - Non-specific, pattern-based approach
> cannot definitively diagnose lung conditions
> similar to interpretation of thoracic x-rays findings
Focused ECHO
- what is the purpose? not a replacement for what?
- Investigate causes of clinical signs > immediate treatment decisions
> pericardial effusion
> volume status (hypovolemia), cardiac contractility (systolic dysfunction, DCM)
> LA enlargement (L-CHF, volume overload), R-sided enlargement (PH)
> cardiac mass(es), thrombus, thickened valves (endocarditis)
() - Particularly useful in cats: respiratory distress
> +/- murmur, gallop, non-specific radiographic findings
> differentiate heart failure from other causes
() - DO NOT replace formal echocardiography
Focused ECHO scanning position? views?
- Scanning position: standing or sternal*
() - R parasternal long-axis view:
> Four-chamber view
() - R parasternal short-axis view:
> LV papillary muscle (mushroom) view
> Mitral valve (fish-mouth) view
> LA:Ao (Mercedes-Benz) view
Focused ECHO
- Tips & tricks:
- rolled towel under cranial thorax
- optimize probe maneuverability, better heart base visualization - point of maximal intensity (PMI)
- reference mark towards shoulder/elbow
- find short-axis (mushroom) view 1st
