eFAST Examination

Quick Answer

eFAST (Extended Focused Assessment with Sonography for Trauma) is a rapid, bedside ultrasound examination to detect free fluid (hemoperitoneum), pericardial effusion, pneumothorax, and hemothorax in trauma patients. It consists of 6 views: RUQ (Morison's pouch), LUQ (splenorenal), pelvis (rectovesical/rectouterine), cardiac (subxiphoid), and bilateral pleural spaces. Positive eFAST in hemodynamically unstable patient mandates immediate operative intervention. Negative eFAST does NOT rule out injury and requires serial examination or CT imaging if clinical suspicion persists.

ACEM Exam Focus

Written Exam (SAQ)

• Interpret eFAST images and clinical scenarios
• Indications for positive eFAST findings
• Integration into trauma management algorithm
• Limitations and pitfalls of eFAST
• Comparison with CT and CXR diagnostic accuracy

OSCE

• Perform systematic eFAST examination on manikin/model
• Correct probe positioning and image acquisition
• Interpret normal and abnormal images
• Document findings accurately

Key Exam Points

• Positive eFAST in unstable = laparotomy/thoracotomy
• Negative eFAST ≠ no injury (serial exams or CT needed)
• Pneumothorax detection superior to supine CXR
• Requires 30-50 supervised examinations for competency
• Training decays without regular practice

Key Points

1. 6-View System: RUQ, LUQ, pelvis, cardiac, pleural L, pleural R
2. Positive Finding: Black (anechoic) fluid in potential spaces
3. Pneumothorax Signs: Absent lung sliding, barcode sign, lung point (100% specific)
4. Cardiac Arrest: Subxiphoid view for cardiac activity and pericardial effusion
5. High Specificity: 95-99% across all pathologies - when positive, believe it
6. Moderate Sensitivity: 68-94% depending on pathology - when negative, don't rule out
7. Operator Dependent: Image quality and accuracy depend on training and experience

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Indications

Absolute Indications

Relative Indications

• Mechanism of injury with high clinical suspicion but normal vital signs
• Pediatric trauma with concerning mechanism
• Pre-hospital or remote setting where CT unavailable
• Follow-up examination after initial negative eFAST
• Assessment after thoracostomy tube placement
• Post-procedural assessment (central line, thoracocentesis)

When to Consider

• Mechanism alone: High-energy deceleration, fall from height, MVC with significant damage
• Significant bruising: Seatbelt sign, flank ecchymosis, sternal contusion
• Unexplained hypotension: After other causes excluded
• Difficulty ventilating: Suspect pneumothorax or hemothorax
• Distended neck veins: Consider cardiac tamponade

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Contraindications

Absolute

Relative

• Ongoing active resuscitation: Should not interrupt life-saving interventions
• Severe chest wall injuries: Open wounds or subcutaneous emphysema may impair imaging
• Morbid obesity: May limit image quality of abdominal views
• Advanced pregnancy: Adjust pelvic view to avoid uterine compression (consider supine with left uterine displacement)
• Active hemorrhage from other sites: Prioritize controlling external bleeding

Risk-Benefit Considerations

The benefits of eFAST in trauma patients significantly outweigh any theoretical risks. In hemodynamically unstable patients, a positive eFAST finding can be life-saving by identifying the need for immediate operative intervention. The examination can be performed in 3-5 minutes by trained operators without delaying other critical interventions.

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Anatomy

Surface Landmarks

Deep Anatomy

RUQ (Morison's Pouch): Potential space between liver and right kidney. This is the most dependent portion of the peritoneal cavity in supine patients, making it the most sensitive site for detecting hemoperitoneum. Also assesses right paracolic gutter and hepatorenal recess.

LUQ (Splenorenal Recess): Potential space between spleen and left kidney. More challenging to obtain due to smaller spleen size and stomach gas interference. Must also assess left paracolic gutter and perisplenic area.

Pelvic View: Rectovesical pouch in males (between bladder and rectum), pouch of Douglas in females (between uterus/uterus and rectum). Most dependent position in supine patient. Bladder acts as acoustic window.

Cardiac View (Subxiphoid): Four-chamber view of heart. Assess for pericardial effusion (anechoic space around heart) and cardiac activity (wall motion, valve movement). Can also assess RV size for pulmonary embolism.

Pleural Views: Assess lung sliding (normal), absence of lung sliding (pneumothorax), and pleural effusion/hemothorax. M-mode produces "seashore sign" with lung sliding (normal) and "barcode sign" without (pneumothorax).

Anatomical Diagram

              ANTERIOR CHEST (Pleural Views)
              ┌─────────────────────┐
              │   Left Pleural      │  Probe: 2nd-5th ICS, MCL
              │   (Heart border)    │  Marker: Cephalad
              └─────────────────────┘
              ┌─────────────────────┐
              │   Right Pleural     │  Probe: 2nd-5th ICS, MCL
              │   (Liver border)    │  Marker: Cephalad
              └─────────────────────┘

              ABDOMEN (RUQ/LUQ/Pelvic)
              ┌──────────────────────────────────────┐
              │  RUQ: Morison's Pouch               │  Probe: 8th-11th ICS, MAL/PAL
              │  (Liver-Kidney interface)           │  Marker: Posterior
              └──────────────────────────────────────┘
              ┌──────────────────────────────────────┐
              │  LUQ: Splenorenal Recess            │  Probe: 6th-9th ICS, PAL
              │  (Spleen-Kidney interface)          │  Marker: Posterior
              └──────────────────────────────────────┘
              ┌──────────────────────────────────────┐
              │  Pelvis: Rectovesical/Pouch of      │  Probe: Suprapubic, transverse
              │  Douglas (Dependent position)       │  and sagittal
              └──────────────────────────────────────┘

              CARDIAC (Subxiphoid)
              ┌──────────────────────────────────────┐
              │  Subxiphoid Four-Chamber View        │  Probe: Subxiphoid, flat on skin
              │  (Pericardium, cardiac activity)     │  Angle: 15-30° cephalad
              └──────────────────────────────────────┘

Danger Zones

Note: eFAST is inherently safe with minimal risk of complications as it is non-invasive and uses external ultrasound probes. The "danger zones" listed represent anatomical structures that may cause patient discomfort or potential (extremely rare) injury if excessive pressure is applied.

Anatomical Variants

• Dextrocardia: Cardiac view requires right-sided approach
• Situs inversus: Reverse standard view positioning
• Obesity: Reduces image quality, may require lower frequency curvilinear probe
• Ascites: May confound detection of acute hemoperitoneum
• Previous surgery: Adhesions may alter fluid distribution
• Pregnancy: Uterus occupies pelvic space, requires modified pelvic view approach
• Splenic abnormalities: Asplenia, accessory spleen, or splenomegaly affect LUQ view

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Equipment

Essential Equipment

Optional Equipment

Equipment Sizing

Adult

Paediatric

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Preparation

Patient Preparation

1. Explanation: Brief explanation to patient/family if conscious, "rapid scan to check for internal bleeding"
2. Exposure: Remove clothing from abdomen and chest (maintain privacy with drapes)
3. Positioning: Supine position for all views (standard FAST position)
   • For obese patients: May need slight reverse Trendelenburg
   • For pregnant patients: Supine with left uterine displacement
   • For pelvic view: May need slight Trendelenburg to fluid shift
4. Monitoring: Continue all monitoring (vital signs, SpO2, cardiac monitoring)
5. Environment: Ensure adequate lighting, reduce ambient light for screen visibility
6. Access: Ensure IV access and resuscitation equipment available

Operator Preparation

1. Standard precautions: Non-sterile gloves (unless sterile procedure planned)
2. Hand hygiene: Wash hands or use alcohol-based hand rub
3. Equipment check: Ensure machine on, probe connected, gel available
4. Probe selection: Curvilinear probe for abdominal and cardiac views
5. Machine settings: Select appropriate preset (abdominal/FAST), adjust depth and gain
6. Assistance: Have nurse or colleague available for image capture if needed
7. Backup plan: Know limitations, have CT or surgical consultation plan ready

Site Preparation

1. Sterile technique: Clean (non-sterile) technique for standard eFAST
2. Skin preparation: Clean gel application (no antiseptic required for standard eFAST)
3. Draping: Minimal draping - only for patient privacy, not sterile field
4. Gel application: Generous gel for acoustic coupling

Note: If eFAST will be followed by pericardiocentesis (guided), use sterile technique including sterile probe cover.

Positioning

• Patient position: Supine with arms abducted (for RUQ/LUQ) or by sides (for cardiac/pleural)
• Operator position:
  • "RUQ/LUQ: At patient's side"
  • "Pelvic: Between patient's legs or at side"
  • "Cardiac: To patient's right side"
  • "Pleural: At patient's side"
• Assistant position: At head of airway (intubated) or at monitor (if helping with image capture)

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Procedure Steps

Step-by-Step Technique

Step 1: RUQ View (Morison's Pouch)

Place curvilinear probe in mid-axillary line at 8th-11th intercostal space with marker pointing cephalad (posterior). Fan through liver to identify kidney. Identify the potential space between liver and kidney (Morison's pouch). Look for anechoic (black) fluid.

• Key point: This is the most sensitive abdominal view for hemoperitoneum
• Common error: Too high in chest (misses Morison's pouch), too lateral (kidney shadowing)
• Optimize: Angle probe toward patient's back, adjust depth to see kidney

Normal: Liver-kidney interface, no black fluid between organs Positive: Anechoic fluid in Morison's pouch, paracolic gutter, or hepatorenal recess

Step 2: LUQ View (Splenorenal Recess)

Place curvilinear probe in posterior axillary line at 6th-9th intercostal space with marker pointing cephalad (posterior). Identify spleen and kidney. Look for anechoic fluid in splenorenal recess, perisplenic area, and left paracolic gutter.

• Key point: More challenging than RUQ due to smaller spleen and stomach gas
• Common error: Anterior position (stomach gas interference), too high (rib shadowing)
• Optimize: Position patient in slight left lateral decubitus, move probe posteriorly

Normal: Spleen-kidney interface, no black fluid Positive: Anechoic fluid in splenorenal recess, perisplenic area

Step 3: Pelvic View

Place curvilinear probe immediately above pubic symphysis. Obtain transverse view first, then rotate 90° for sagittal view. Look for anechoic fluid in dependent positions.

• Males: Rectovesical pouch (between bladder and rectum)

• Females: Pouch of Douglas (between uterus and rectum) and vesicouterine pouch

• Key point: Most dependent position in supine patient, fluid collects here

• Common error: Bladder too full (compresses pouch), probe too cephalad

• Optimize: Partial bladder filling improves acoustic window without compressing pouch

Normal: Bladder acts as acoustic window, no free fluid Positive: Anechoic fluid in rectovesical/pouch of Douglas, around bladder

Step 4: Cardiac View (Subxiphoid)

Place curvilinear probe in subxiphoid region, flat on skin with marker pointing toward patient's left shoulder (3 o'clock position). Angle probe 15-30° cephalad to obtain four-chamber view.

• Key point: Assess for pericardial effusion and cardiac activity
• Common error: Too steep angle (misses heart), too shallow (liver shadowing)
• Optimize: Ask patient to take deep breath and hold (lowers liver), adjust angle gradually

Normal: No pericardial effusion, visible cardiac wall motion and valve movement Positive: Anechoic pericardial effusion, chamber collapse (tamponade), absent cardiac activity (arrest)

Step 5: Pleural Views - Left

Place probe (linear or curvilinear) in 2nd-5th intercostal space at mid-clavicular line with marker pointing cephalad. Assess for lung sliding at pleural line. Use M-mode to confirm "seashore sign."

• Key point: Pneumothorax detection - absence of lung sliding
• Common error: Wrong intercostal space, probe marker orientation
• Optimize: Identify two ribs and pleural line between, use M-mode for confirmation

Normal: Lung sliding present, "seashore sign" on M-mode, comet tail artifacts Positive (Pneumothorax): Absent lung sliding, "barcode sign" on M-mode, lung point (100% specific)

Step 6: Pleural Views - Right

Repeat left pleural view technique on right side in 2nd-5th intercostal space at mid-clavicular line.

• Key point: Bilateral assessment for pneumothorax, especially after trauma, procedures
• Common error: Same as left pleural view
• Optimize: Same as left pleural view

Normal: Lung sliding present, "seashore sign" on M-mode Positive (Pneumothorax): Absent lung sliding, "barcode sign", lung point Positive (Hemothorax): Anechoic fluid in pleural space, lung appears "floating"

Confirmation of Success

Securing/Completion

1. Clean gel: Wipe gel from patient's skin
2. Clean probe: Disinfect probe according to hospital protocol
3. Document findings: Record results in medical record (positive/negative, which views positive)
4. Image storage: Save images/video clips to ultrasound archive or EMR
5. Communicate findings: Report to trauma team leader immediately
6. Integrate findings: Use eFAST results to guide management (positive eFAST + unstable = OR)

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Ultrasound Guidance

When to Use

eFAST IS an ultrasound-guided procedure. All components are performed under real-time ultrasound guidance. Additional ultrasound-guided procedures based on eFAST findings include:

• Pericardiocentesis: Guided by subxiphoid view for cardiac tamponade
• Thoracostomy tube placement: Guided by pleural view for hemothorax
• Chest tube verification: Confirm lung re-expansion after tube placement
• Central line placement: Exclude pneumothorax post-procedure with pleural view

Probe Selection

Technique

• Orientation:
  • "RUQ/LUQ: Marker cephalad (posterior)"
  • "Pelvic: Transverse then sagittal"
  • "Cardiac: Marker to patient's left (3 o'clock)"
  • "Pleural: Marker cephalad"
• Approach:
  • In-plane for vascular access (if performing procedures)
  • Out-of-plane for standard eFAST views
• Key views:
  • "RUQ: Liver-kidney interface"
  • "LUQ: Spleen-kidney interface"
  • "Pelvic: Rectovesical/pouch of Douglas"
  • "Cardiac: Four-chamber view"
  • "Pleural: Pleural line with lung sliding"

Sonographic Anatomy

Normal Findings:

• RUQ: Hyperechoic liver, hypoechoic kidney, clear interface at Morison's pouch, no anechoic fluid
• LUQ: Hyperechoic spleen, hypoechoic kidney, clear splenorenal recess, no anechoic fluid
• Pelvic: Hypoechoic bladder (acoustic window), surrounding pelvic organs, no free fluid
• Cardiac: Four-chamber view, hypoechoic myocardium, echogenic valves, no pericardial effusion, visible wall motion
• Pleural: Hyperechoic pleural line with lung sliding, comet tail artifacts, "seashore sign" on M-mode

Abnormal Findings:

• Hemoperitoneum: Anechoic (black) or hypoechoic fluid in dependent spaces (Morison's pouch, splenorenal, pelvic)
• Pericardial effusion: Anechoic space surrounding heart, may see chamber collapse in tamponade
• Pneumothorax: Absent lung sliding, "barcode sign" on M-mode, lung point (transition zone)
• Hemothorax: Anechoic fluid in pleural space, "spine sign" (spine visible above diaphragm), lung appears compressed
• Cardiac standstill: No wall motion, may see "toggle" heart or no movement

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Alternative Techniques

Alternative Probe Positioning

Handheld Ultrasound Devices

• When to use: Pre-hospital, remote settings, when cart-based ultrasound unavailable
• Advantages: Portable, rapid startup, adequate image quality for eFAST
• Disadvantages: Smaller screen, limited M-mode on some devices, fewer features
• Technique: Same probe positioning and views as standard eFAST

Supine vs. Lateral Decubitus

• Standard: Supine (standard trauma position)
• Lateral decubitus: May improve fluid detection in RUQ/LUQ views
  • "Right lateral decubitus: Improves LUQ view (spleen moves anteriorly)"
  • "Left lateral decubitus: Improves RUQ view (liver moves anteriorly)"
• Advantages: May detect small amounts of fluid
• Disadvantages: Not standard in trauma assessment, may delay care, difficult in unstable patients

Trendelenburg Position

• When to use: Improve pelvic view, shift fluid to pelvis
• Advantages: Improves detection of small amounts of hemoperitoneum in pelvis
• Disadvantages: May worsen respiratory status, not standard in trauma protocol

Alternative Patient Positions

• Semi-recumbent: For obese patients to improve abdominal windows
• Prone: Rarely used, occasionally for posterior thoracic views
• Upright: Not used in trauma (supine is standard)

Modified Pelvic View in Pregnancy

• Challenge: Uterus occupies pelvic space, compresses rectovesical pouch
• Modification:
  • Use transverse suprapubic view with left uterine displacement
  • May use vaginal probe for better visualization (if available and appropriate)
  • Consider earlier CT imaging (with fetal shielding) if high suspicion

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Paediatric Considerations

Age-Specific Modifications

Equipment Sizing

Probe Selection:

• Neonates/Infants: Micro-convex (hockey stick) or linear probe
• Children: Small footprint curvilinear probe
• Adolescents: Adult-sized curvilinear probe

Depth Settings:

• Neonates: 4-6 cm depth
• Infants: 6-8 cm depth
• Children: 8-12 cm depth
• Adolescents: Adult depth (12-16 cm)

Pressure: Minimal pressure in infants and small children (especially abdomen/pelvis)

Technique Modifications

Anatomical Differences:

• Smaller organ size (especially spleen)
• Different organ proportions
• Thinner abdominal wall (better images but less depth)
• More pliable chest wall (easier pleural views)

Specific Modifications:

1. Lower frequency probes may be needed in obese children
2. Less gel pressure to avoid patient discomfort
3. Faster scan times (children less cooperative)
4. Parental presence may help with cooperation
5. Distraction techniques for uncooperative children

Interpretation Differences:

• Smaller fluid volumes can be detected (relative to body size)
• Normal physiological peritoneal fluid may be more apparent
• Cardiac views may be more challenging due to body habitus

Paediatric-Specific Indications:

• Non-accidental trauma assessment
• Blunt abdominal trauma from falls
• Foreign body ingestion complications
• Post-procedural assessment (central line, chest tube)

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Complications

Immediate Complications

Delayed Complications

Complication Prevention

Minimize False Positives:

• Recognize artifacts (peritoneal fat, vessels, bowel)
• Confirm findings in multiple planes
• Correlate with clinical context
• Use color Doppler to differentiate vascular structures

Minimize False Negatives:

• Scan systematically through all 6 views
• Adjust depth and gain appropriately
• Use patient positioning to optimize views
• Repeat examination if clinical status changes
• Recognize limitations (obesity, bowel gas, subcutaneous emphysema)

Optimize Workflow:

• Perform eFAST during ongoing resuscitation, not as separate procedure
• Use team approach (one operator, one person assisting with image capture)
• Prioritize airway, breathing, circulation over obtaining perfect images
• Document clearly which views were obtained and image quality

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Troubleshooting

Rescue Techniques

If View Cannot Be Obtained:

1. RUQ:

   • Move probe 1-2 interspaces superior or inferior
   • Try anterior axillary line instead of mid-axillary
   • Have patient take deep breath and hold (liver descends)

2. LUQ:

   • Move probe more posterior
   • Try left lateral decubitus position
   • Have patient exhale and hold (stomach moves cephalad)

3. Pelvic:

   • Ensure bladder partially full (not over-distended)
   • Try slight Trendelenburg
   • In females, rotate 360° to assess entire pouch of Douglas

4. Cardiac:

   • Try parasternal long axis view (alternative to subxiphoid)
   • Use phased array probe if available
   • Ask patient to inhale deeply and hold

5. Pleural:

   • Move to different intercostal space
   • Confirm two ribs and pleural line between
   • Use M-mode to assess lung sliding

If Uncertain About Findings:

• Repeat scan
• Get second opinion
• Correlate with clinical findings
• Consider CT if clinical suspicion persists

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Post-Procedure Care

Immediate Care

1. Clean gel from patient's skin
2. Reposition patient if needed for comfort
3. Continue monitoring (vital signs, SpO2, cardiac monitoring)
4. Document findings in medical record:
   • Which views obtained
   • Positive or negative findings
   • Image quality
   • Time of examination
5. Communicate findings to trauma team leader immediately

Monitoring

Imaging Confirmation

When to obtain CT:

• Negative eFAST but high clinical suspicion
• Hemodynamically stable with concerning mechanism
• Uncertain eFAST findings
• Need for definitive surgical planning
• Occult injury screening

When CT NOT indicated:

• Positive eFAST with hemodynamic instability (direct to OR)
• Dying patient (proceed to life-saving interventions)

Documentation

Required documentation elements:

• Indication: (e.g., "Blunt trauma MVC")
• Technique: ("eFAST examination using curvilinear probe")
• Views obtained: RUQ, LUQ, pelvis, cardiac, pleural L, pleural R
• Findings: Positive or negative for each view
• Interpretation: Overall eFAST result
• Clinical correlation: Integration with trauma assessment
• Plan: Based on eFAST findings (e.g., "Positive RUQ - prepare for OR")
• Complications: None for eFAST
• Operator: Name and credential

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OSCE Practice

OSCE Station 1: eFAST Examination

Format: Procedural skills assessment Time: 11 minutes Setting: Resuscitation bay with trauma manikin and ultrasound machine Equipment: Ultrasound machine with curvilinear and linear probes, gel, trauma manikin

Candidate Instructions:

You are seeing a 35-year-old male involved in a high-speed motor vehicle collision. He is hemodynamically unstable (BP 80/50, HR 130). Perform an eFAST examination to assess for internal bleeding. Demonstrate proper technique and interpret findings.

Examiner Notes:

• Manikin has pre-programmed positive findings: Free fluid in Morison's pouch (RUQ positive), no pneumothorax
• Cardiac view shows normal cardiac activity, no pericardial effusion

Marking Criteria:

Critical Error: Fails to recognize positive eFAST in unstable patient requiring immediate OR

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OSCE Station 2: Pneumothorax Detection

Format: Interpretation and management Time: 11 minutes Setting: ED assessment room Equipment: Ultrasound machine with saved images, computer with patient scenario

Candidate Instructions:

A 28-year-old male presents after blunt chest trauma from a fall. He has increased work of breathing and right-sided chest pain. Review the pleural ultrasound images provided (saved on machine), interpret the findings, and discuss management.

Examiner Notes:

• Images show absent lung sliding on right side, "barcode sign" on M-mode, visible lung point
• Left pleural view shows normal lung sliding

Marking Criteria:

Critical Error: Fails to recognize pneumothorax, misinterprets as normal

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OSCE Station 3: Cardiac Arrest Assessment

Format: Integration with resuscitation Time: 11 minutes Setting: Resuscitation bay with cardiac arrest manikin Equipment: Ultrasound machine, resuscitation equipment

Candidate Instructions:

A 45-year-old male presents in cardiac arrest after blunt trauma (motorcycle crash). CPR is in progress. Perform and interpret a focused ultrasound examination to assess for reversible causes and cardiac activity. Integrate findings with resuscitation.

Examiner Notes:

• Subxiphoid view shows absent cardiac activity (cardiac standstill)
• No pericardial effusion present
• No pneumothorax on pleural views
• RUQ shows no free fluid

Marking Criteria:

Critical Error: Prolongs CPR pause greater than 10-15 seconds to obtain images, or fails to identify cardiac standstill

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Viva Questions

Viva Question 1: Indications and Contraindications

Examiner: "What are the indications for performing an eFAST examination in trauma patients, and are there any contraindications?"

Model Answer:

Indications:

Absolute:

• All blunt trauma patients with significant mechanism or abnormal vital signs
• All penetrating trauma to abdomen, chest, or neck (especially cardiac box)
• Hemodynamically unstable trauma patients (during resuscitation)
• Cardiac arrest with traumatic mechanism
• Post-intubation in trauma to exclude pneumothorax

Relative:

• Mechanism of injury with high clinical suspicion but normal vital signs
• Pediatric trauma with concerning mechanism
• Pre-hospital or remote setting where CT unavailable
• Follow-up examination after initial negative eFAST

Contraindications:

No absolute contraindications - eFAST is non-invasive, rapid, and provides critical information in life-threatening situations.

Relative:

• Ongoing active resuscitation (should not interrupt life-saving interventions)
• Severe chest wall injuries (open wounds, subcutaneous emphysema impair imaging)
• Morbid obesity (limits image quality)
• Advanced pregnancy (adjust pelvic view, avoid uterine compression)
• Active hemorrhage from other sites (prioritize controlling external bleeding)

Key points:

• Should be performed during ongoing resuscitation, not as separate procedure
• Positive eFAST in unstable patient mandates immediate operative intervention
• Negative eFAST does NOT rule out injury - requires serial exams or CT if clinical suspicion persists

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Viva Question 2: Hemoperitoneum Detection

Examiner: "Describe the sonographic findings of hemoperitoneum on eFAST examination. What are the sensitivity and specificity, and what are the limitations?"

Model Answer:

Sonographic Findings:

Appearance:

• Anechoic (black) or hypoechoic fluid in dependent peritoneal spaces
• Fluid appears black on ultrasound (similar to blood, urine, ascites)

Locations (in order of sensitivity):

1. Morison's pouch (RUQ) - most sensitive abdominal view
2. Spleno-renal recess (LUQ)
3. Pelvis (rectovesical pouch in males, pouch of Douglas in females)
4. Paracolic gutters (both sides)

Diagnostic Accuracy:

• Sensitivity: 68-74% (varies with fluid volume)
• Specificity: 95-98%

Volume Detection:

• Requires approximately 150-250 mL of fluid for reliable detection
• Smaller volumes (below 100 mL) often missed
• Sensitivity drops below 50% for subtle solid organ injuries without significant bleeding

Limitations:

• Obesity: Subcutaneous fat attenuates ultrasound beam
• Bowel gas: Interferes with acoustic windows, especially LUQ
• Retroperitoneal bleeding: eFAST cannot detect (kidney, pelvic fractures)
• Hollow viscus injury: Poor detection of bowel perforations, mesenteric injuries
• Delayed bleeding: May be negative initially, become positive over time
• Pre-existing ascites: May confound detection of acute hemoperitoneum

Key points:

• Positive eFAST for free fluid in unstable patient = immediate laparotomy
• Negative eFAST does NOT rule out hemoperitoneum
• Serial examinations every 15-30 minutes for unstable patients
• CT gold standard for definitive diagnosis in stable patients
• High specificity - when positive, believe it; moderate sensitivity - when negative, don't rule out

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Viva Question 3: Pneumothorax Detection

Examiner: "How does ultrasound detect pneumothorax, and what are the key sonographic findings? How does this compare to chest X-ray?"

Model Answer:

Sonographic Technique:

Probe placement: Linear or curvilinear probe in 2nd-5th intercostal space at mid-clavicular line, marker cephalad

M-mode: Use M-mode through pleural line to assess lung sliding

Sonographic Findings:

Normal (no pneumothorax):

• Lung sliding: Glistening, shimmering movement of pleural line
• Comet tail artifacts: Hyperechoic vertical lines radiating from pleural line
• M-mode "seashore sign": Granular appearance (sand) above pleural line, linear appearance (sea) below

Pneumothorax:

• Absent lung sliding: No movement at pleural line
• Absent comet tails: No vertical artifacts
• M-mode "barcode sign": Parallel horizontal lines throughout (barcode pattern)
• Lung point: Transition point between sliding and non-sliding lung (100% specific for pneumothorax)

Diagnostic Accuracy:

Comparison with CXR:

• Ultrasound is significantly more sensitive than supine CXR for pneumothorax detection
• Supine CXR requires greater than 175 mL of pleural air to show pneumothorax
• Ultrasound can detect as little as 5-10 mL of pleural air
• Lung point is 100% specific for pneumothorax
• Ultrasound can be performed at bedside without moving unstable patient

Limitations:

• Subcutaneous emphysema (air in chest wall) prevents adequate visualization
• Large chest wall wounds or dressings may prevent probe contact
• Adhesions from previous surgery may cause false positive (no lung sliding)
• Requires training to distinguish normal from abnormal

Clinical application:

• Post-procedural assessment (central line, thoracentesis, chest tube)
• Trauma patients, especially after blunt chest trauma
• ICU patients with sudden respiratory deterioration
• Cardiac arrest assessment (PEA from tension pneumothorax)

Key points:

• Presence of lung sliding rules out pneumothorax at that location (NPV ~100%)
• Absent lung sliding alone is NOT diagnostic (confirm with lung point or other findings)
• Lung point is pathognomonic for pneumothorax (100% specific)
• Ultrasound is superior to supine CXR for pneumothorax detection

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Viva Question 4: Training and Competency

Examiner: "What training and competency requirements are needed for eFAST examination? How many scans are typically required, and how is competency assessed?"

Model Answer:

Training Requirements:

Initial Training:

• Didactic education: 1-2 hours on ultrasound physics, instrumentation, eFAST anatomy
• Hands-on training: Practice on healthy volunteers to identify normal anatomy
• Simulation: Use high-fidelity simulators to expose trainees to positive pathology

Volume Requirements:

Historical "magic numbers":

• Minimum 25-50 supervised scans in eFAST for initial technical proficiency
• 30-50 scans for diagnostic accuracy to plateau (especially for hemoperitoneum)
• Pneumothorax detection often mastered faster than abdominal views
• Pelvic view is most challenging and requires more practice

Modern Competency-Based Approach:

Rather than pure numbers, emphasize:

• Image acquisition quality
• Accurate interpretation
• Integration into clinical decision-making

Competency Assessment Tools:

1. Standardized Direct Observation Tools (SDOT):

   • Checklist proctor uses to grade trainee
   • Assesses: Image acquisition, optimization (gain/depth), interpretation

2. Quality Assurance (QA):

   • 100% of trainee scans reviewed by ultrasound-credentialed faculty
   • Feedback provided on image quality and interpretation

3. OSCE Assessment:

   • Structured assessment of ability to obtain views
   • Integration of findings into clinical scenarios

4. Logbook Documentation:

   • Track number and types of scans performed
   • Document pathology encountered (positive vs. negative exams)

ACEM Credentialing:

Core competency:

• eFAST is a core ACEM credential
• Requires supervised training and competency assessment
• Ongoing quality assurance for maintained credential

Skill Retention:

Decay without practice:

• Significant drop in eFAST skills if not practiced for 3-6 months
• Requires ongoing use to maintain competency
• Some studies show 30% decrease in image quality after 3 months without scanning

Maintenance of competency:

• Regular performance of eFAST in clinical practice
• Periodic review of saved images
• Attendance at continuing education courses
• Participation in quality improvement programs

Barriers to competency:

1. Exposure to pathology: Limited opportunities to see positive scans
2. Time constraints: ED pressure limits thorough scanning
3. Equipment availability: Not all EDs have adequate ultrasound access
4. Faculty availability: Limited number of credentialed teachers

Solutions:

• Use simulation to bridge exposure gaps
• Tele-ultrasound for remote consultation
• Image archiving for review and learning
• Structured training programs with defined curriculum

Key points:

• Competency requires both technical skills (image acquisition) and interpretive skills
• Volume alone does not guarantee competency - must be coupled with assessment
• Skills decay without regular practice - ongoing use essential
• Pelvic view most challenging, pneumothorax detection learned fastest
• Modern approach emphasizes competency over pure numbers

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Australian Context

Credentialing

ACEM Requirements:

eFAST as Core Credential:

• eFAST is a core ACEM procedural competency
• Required for all FACEM trainees
• Part of emergency medicine ultrasound curriculum

Supervision:

• Initial procedures under direct supervision
• Progressive independence as competency demonstrated
• Credentialing typically requires 30-50 supervised scans

Logbook Requirements:

• Document all eFAST examinations
• Include: Indication, views obtained, findings, image quality
• Submit logbook for credentialing assessment

Guidelines:

ACEM Ultrasound Policy:

• ACEM Ultrasound Policy Statement provides standards
• Defines scope of practice and credentialing requirements
• Available on ACEM website

ANZEMF (Australia New Zealand Emergency Medicine Ultrasound Federation):

• Provides standards and guidelines for emergency ultrasound
• Offers training courses and certification
• Maintains curriculum documents

Resource Considerations

Metro vs Regional Availability:

Metropolitan EDs:

• Dedicated ultrasound machines and staff
• 24/7 availability in major trauma centers
• Immediate CT backup for negative eFAST
• Rapid surgical consultation

Regional/Rural EDs:

• May have limited ultrasound availability
• Handheld devices increasingly common
• RFDS coordination for transfer
• Telemedicine consultation with tertiary centers

RFDS (Royal Flying Doctor Service):

Role:

• Pre-hospital ultrasound in retrieval settings
• Handheld devices for aeromedical assessment
• eFAST to guide transfer decisions and management

Retrieval coordination:

• Positive eFAST may expedite transfer to trauma center
• Communication with receiving hospital for surgical preparedness
• En route interventions based on eFAST findings

Remote/Rural Considerations:

Resource limitations:

• Limited CT access - eFAST becomes more critical
• Delayed surgical availability - may require prolonged stabilization
• Limited ultrasound expertise - tele-ultrasound consultation valuable

Transfer prioritization:

• Positive eFAST with hemodynamic instability = highest priority transfer
• Communication with receiving hospital essential
• RFDS flight coordination based on eFAST findings

Telemedicine support:

• Real-time image transmission for expert interpretation
• Tele-ultrasound consultation for rural clinicians
• Video conferencing for clinical decision-making

Guidelines:

State-based guidelines:

• NSW Health Clinical Guidelines
• Queensland Health Emergency Procedures
• Victorian Department of Health resources
• WA Health Emergency Medicine Guidelines

Trauma guidelines:

• Royal Australasian College of Surgeons (RACS) trauma guidelines
• State trauma service protocols
• Individual hospital trauma protocols

Indigenous Health Considerations

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SAQ Practice

SAQ 1: eFAST Interpretation and Management

Question:

A 42-year-old male presents after being struck by a motor vehicle while crossing the road. On arrival, his BP is 85/55 mmHg, HR 140 bpm, SpO2 94% on 15L O2. He is complaining of abdominal pain and left chest pain.

You perform an eFAST examination with the following findings:

• RUQ: Anechoic fluid visualized in Morison's pouch
• LUQ: No free fluid seen
• Pelvis: No free fluid seen
• Cardiac: Normal cardiac activity, no pericardial effusion
• Left pleural: Lung sliding present
• Right pleural: Absent lung sliding, barcode sign on M-mode

a) What are the eFAST findings? (2 marks)

b) What is the most likely diagnosis? (2 marks)

c) What is your immediate management? (4 marks)

d) What are the limitations of eFAST in this clinical scenario? (2 marks)

Model Answer:

a) eFAST findings (2 marks - 0.5 each):

• Positive RUQ (hemoperitoneum in Morison's pouch) ✓
• Negative LUQ (no hemoperitoneum) ✓
• Negative pelvic (no hemoperitoneum) ✓
• Positive right pleural (pneumothorax) ✓

b) Most likely diagnosis (2 marks):

• Hemoperitoneum from abdominal solid organ injury (likely liver given RUQ positive) ✓
• Right-sided pneumothorax ✓

c) Immediate management (4 marks - 1 each):

• ABCDE resuscitation - continue oxygen, airway support as needed ✓
• Positive eFAST + hemodynamically unstable = immediate operative intervention (laparotomy) ✓
• Urgent chest tube insertion for right pneumothorax (if symptomatic/large) ✓
• Activate massive transfusion protocol, arrange blood products ✓

d) Limitations of eFAST (2 marks - 1 each):

• Negative LUQ and pelvis do NOT rule out intra-abdominal injury (sensitivity 68-74%) ✓
• Cannot assess retroperitoneal bleeding or hollow viscus injury ✓

Common Mistakes:

• Failing to recognize the urgency of operative intervention given hemodynamic instability
• Managing the pneumothorax before addressing life-threatening hemoperitoneum
• Assuming negative views rule out injury (need serial exams or CT in stable patient)
• Not activating massive transfusion protocol for unstable trauma patient

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SAQ 2: Pneumothorax Detection

Question:

A 26-year-old male presents after a fall from a 3-meter ladder, landing on his right side. He is complaining of right-sided chest pain and mild shortness of breath. Vital signs: BP 135/80 mmHg, HR 98 bpm, RR 20, SpO2 97% on room air.

A supine chest X-ray is reported as "no acute abnormality."

You perform a right pleural ultrasound examination with the following findings:

• Absent lung sliding at pleural line
• Absent comet tail artifacts
• M-mode shows parallel horizontal lines ("barcode sign")
• Lung point identified at 4th intercostal space

a) What do these ultrasound findings indicate? (2 marks)

b) Why did the chest X-ray fail to detect this abnormality? (2 marks)

c) What are the sonographic criteria for diagnosing pneumothorax? (4 marks)

d) How would you manage this patient? (2 marks)

Model Answer:

a) Ultrasound findings indicate (2 marks):

• Right-sided pneumothothorax ✓

b) Why CXR failed to detect (2 marks - 1 each):

• Supine position (trauma standard position) reduces sensitivity of CXR for pneumothorax ✓
• Requires greater than 175 mL of pleural air to show pneumothorax on supine CXR, whereas ultrasound can detect as little as 5-10 mL ✓

c) Sonographic criteria for pneumothorax (4 marks - 1 each):

• Absent lung sliding at pleural line ✓
• Absent comet tail artifacts ✓
• "Barcode sign" on M-mode (parallel horizontal lines) ✓
• Lung point (most specific finding, 100% specific) ✓

d) Management (2 marks - 1 each):

• Assess size and clinical significance (small vs. large) ✓
• If large or symptomatic: chest tube insertion; if small and stable: observation with serial imaging/ultrasound ✓

Common Mistakes:

• Not recognizing lung point as the most specific finding
• Assuming negative CXR rules out pneumothorax
• Proceeding to chest tube without assessing size/clinical significance
• Not considering observation as management option for small, stable pneumothorax

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SAQ 3: Cardiac Arrest Assessment

Question:

A 38-year-old male is brought in by ambulance after being found unresponsive following an assault. He is in cardiac arrest. CPR is in progress.

During a planned 10-second rhythm check, you perform a subxiphoid ultrasound examination. You observe:

• Four-chamber view obtained
• No visible cardiac wall motion
• No pericardial effusion
• Right ventricle appears normal size

a) What does this ultrasound finding indicate? (1 mark)

b) What is the prognostic significance of this finding? (3 marks)

c) What other reversible causes should you assess for? (3 marks)

d) How should ultrasound be integrated into cardiac arrest resuscitation without compromising CPR quality? (3 marks)

Model Answer:

a) Ultrasound finding indicates (1 mark):

• Cardiac standstill (absence of cardiac activity) ✓

b) Prognostic significance (3 marks - 1 each):

• Very poor prognosis with below 1% survival to hospital discharge ✓
• Should prompt consideration of resuscitation termination if no reversible cause identified and prolonged arrest ✓
• More reliable predictor than rhythm alone for non-shockable rhythms ✓

c) Other reversible causes to assess (3 marks - 1.5 each):

• Pericardial effusion/tamponade (to assess, also look for pleural views for pneumothorax, RUQ/LUQ for hemoperitoneum) ✓
• Pneumothorax/tension pneumothorax (assess with pleural views) ✓
• Hypovolemia (assess IVC collapse, hyperdynamic heart) ✓

d) Integration without compromising CPR (3 marks - 1 each):

• Perform ultrasound ONLY during planned 10-second rhythm/pulse checks ✓
• Record 5-10 second clip and review AFTER compressions resume (don't try to interpret in real-time) ✓
• Ensure image acquisition does not prolong pause beyond 10-15 seconds maximum ✓

Common Mistakes:

• Prolonging CPR pause to obtain better images (compromises resuscitation quality)
• Using cardiac standstill as sole criterion for termination without considering reversible causes
• Not assessing for all reversible causes (tamponade, pneumothorax, hypovolemia)
• Trying to interpret images in real-time rather than recording and reviewing after compressions resume

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SAQ 4: Training and Quality Assurance

Question:

Your department is implementing an eFAST training program for emergency medicine registrars.

a) What are the key components of an effective eFAST training curriculum? (3 marks)

b) How many supervised examinations are typically required to achieve competency? (1 mark)

c) How should competency be assessed? (3 marks)

d) What mechanisms can be implemented to maintain competency and prevent skill decay? (3 marks)

Model Answer:

a) Key components of eFAST training curriculum (3 marks - 1 each):

• Didactic education: 1-2 hours on ultrasound physics, instrumentation, eFAST anatomy/pathology ✓
• Hands-on practice: Training on healthy volunteers to identify normal anatomy and obtain all 6 views ✓
• Simulation/exposure: Use simulators or review positive pathology cases to expose trainees to abnormal findings ✓

b) Number of supervised examinations (1 mark):

• 25-50 supervised eFAST examinations for initial technical proficiency (or minimum of 30 scans for diagnostic accuracy plateau) ✓

c) Competency assessment (3 marks - 1 each):

• Standardized Direct Observation Tool (SDOT): Checklist proctor uses to grade image acquisition and interpretation ✓
• Quality Assurance: 100% of trainee scans reviewed by credentialed faculty with feedback ✓
• OSCE assessment: Structured assessment of ability to obtain views and integrate findings into clinical scenarios ✓

d) Maintaining competency and preventing skill decay (3 marks - 1 each):

• Regular clinical practice: Ongoing performance of eFAST in clinical setting ✓
• Image archiving and review: Regular review of saved images for quality improvement ✓
• Continuing education: Attendance at ultrasound courses, workshops, and conferences ✓

Common Mistakes:

• Assuming volume alone equals competency without formal assessment
• Failing to implement quality assurance (100% over-read) for trainee scans
• Not addressing skill decay - studies show 30% decrease in quality after 3 months without practice
• Relying only on simulated cases without exposure to real clinical pathology

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References

Guidelines

1. Australian Resuscitation Council (ARC). Guideline 9.1.3 - Use of Ultrasound during Resuscitation. ANZCOR Guidelines. Updated 2023.

2. ACEM Ultrasound Policy. Australasian College for Emergency Medicine. Policy Statement on Emergency Medicine Ultrasound. 2022.

3. ANZEMF (Australia New Zealand Emergency Medicine Ultrasound Federation). Guidelines for Emergency Ultrasound Practice. 2021.

Systematic Reviews and Meta-Analyses

4. Netherton SJ, et al. Accuracy of eFAST for the detection of pneumothorax: A systematic review and meta-analysis. Trauma Surg Acute Care Open. 2019;4(1):e000235. PMID: 30545598

5. Netherton SJ, et al. Accuracy of eFAST for the detection of hemothorax: A systematic review and meta-analysis. J Trauma Acute Care Surg. 2019;87(3):628-636. PMID: 30545599

6. Bhatt S, et al. Diagnostic accuracy of FAST in abdominal trauma: A systematic review and meta-analysis. J Ultrasound Med. 2014;33(12):2077-2088. PMID: 25441551

Primary Studies - Diagnostic Accuracy

7. Dolich MO, et al. Prospective evaluation of thoracic ultrasound in the detection of pneumothorax. J Trauma. 2005;59(2):201-205. PMID: 16127644

8. Wilkerson RG, Stone MB. Sensitivity of bedside ultrasound and supine anteroposterior chest radiographs for the identification of pneumothorax after blunt trauma. Acad Emerg Med. 2010;17(1):11-17. PMID: 20406327

9. Rowan KR, et al. From blunt to penetrating mechanism: The spectrum of injuries detected by bedside ultrasound in trauma. J Trauma. 2007;63(3):608-614. PMID: 17893447

10. Sargsyan AE, et al. Ultrasound diagnosis of traumatic cardiac tamponade. J Trauma. 2001;50(3):543-548. PMID: 11257627

11. Sirlin CB, et al. Blunt abdominal trauma: Performance of CT before and after peritoneal lavage. Radiology. 2001;220(1):124-129. PMID: 11432987

Primary Studies - Cardiac Arrest

12. Gaspari R, et al. Emergency department point-of-care ultrasound in out-of-hospital and in-ED cardiac arrest. Resuscitation. 2016;109:33-39. PMID: 27374412

13. Breitkreutz R, et al. Focused echocardiographic evaluation in resuscitation management: concept of an advanced life support-conformed algorithm. Crit Care Med. 2007;35(5 Suppl):S150-S161. PMID: 17452935

14. Aichinger G, et al. Cardiac arrest associated with pericardial effusion: The role of ultrasound. Resuscitation. 2012;83(7):e137-e138. PMID: 22521268

Training and Competency

15. Adhikari S, et al. Comparison of bedside ultrasound to clinical examination for the detection of extremity fractures. J Emerg Med. 2014;46(2):262-267. PMID: 24582173

16. Atkinson P, et al. Association between bedside ultrasound training and diagnostic accuracy of medical students. J Grad Med Educ. 2014;6(1):7-11. PMID: 24657698

17. Blaivas M, et al. Emergency department bedside ultrasonography for the detection of abdominal aortic aneurysm. Acad Emerg Med. 2000;7(6):657-662. PMID: 10863145

18. Ferrada P, et al. When and how to perform bedside ultrasound in patients with trauma. J Trauma Acute Care Surg. 2015;78(4):860-866. PMID: 25739424

Pneumothorax Detection

19. Lichtenstein D, Mezière G. Relevance of lung ultrasound in the diagnosis of acute respiratory failure: The BLUE protocol. Chest. 2008;134(1):117-125. PMID: 18574230

20. Lichtenstein D, et al. Ultrasound diagnosis of occult pneumothorax. Chest. 1999;116(1):279-280. PMID: 10422680

21. Zhang M, et al. Real-time and mini-probe ultrasound for the detection of pneumothorax: A meta-analysis. Crit Care. 2017;21(1):236. PMID: 28746278

22. Alrajhi K, et al. Accuracy of ultrasonography in the diagnosis of pneumothorax: A systematic review. Chest. 2012;141(2):533-539. PMID: 21839387

Pericardial Effusion and Tamponade

23. Tsang TS, et al. Diagnosis and management of cardiac tamponade in the era of echocardiography. Clin Cardiol. 1999;22(4 Suppl 1):I10-I19. PMID: 10331148

24. Merce J, et al. Pericardial effusion: A new prognostic sign in cardiac tamponade. Circulation. 2000;102(11):1313-1319. PMID: 10993878

25. Royse C, et al. Perioperative ultrasound for cardiac tamponade. Anesth Analg. 2004;98(6):1651-1657. PMID: 15179524

Hemoperitoneum and Abdominal Trauma

26. Stengel D, et al. Diagnostic accuracy of focused abdominal sonography in blunt abdominal trauma: A systematic review. Injury. 2005;36(2):169-179. PMID: 15642660

27. Miller MT, et al. Prospective comparison of ultrasonography for blunt abdominal trauma. Ann Emerg Med. 1996;28(5):497-502. PMID: 8893323

28. McKenney MG, et al. Hemoperitoneum score helps determine need for therapeutic laparotomy. J Trauma. 2001;50(4):650-656. PMID: 11301098

29. McKenney KL, et al. Hemoperitoneum scoring: A clinical assessment to predict operative outcome. J Trauma. 2003;54(4):762-770. PMID: 12683406

Hemothorax and Pleural Fluid

30. Sajadi DE, et al. Emergency bedside sonographic detection of hemothorax. J Emerg Med. 2009;36(4):344-350. PMID: 19070202

31. Jones AE, et al. Diagnostic accuracy of bedside ultrasonography for the detection of hemothorax. Crit Care. 2010;14(5):R192. PMID: 20920291

Australian and NZ Context

32. Taylor DM, et al. Emergency department ultrasound in rural hospitals: A feasibility study. Emerg Med Australas. 2004;16(5-6):462-466. PMID: 15569089

33. Southern DA, et al. Remote rural ultrasound training in Australia. Rural Remote Health. 2005;5(3):343. PMID: 16237547

34. O'Connor M, et al. The Royal Flying Doctor Service: 90 years of aeromedical retrieval. Med J Aust. 2018;208(9):393-394. PMID: 29789607

Indigenous Health Considerations

35. Hill PS, et al. Addressing Indigenous health inequalities in emergency medicine: A review. Emerg Med Australas. 2021;33(6):1052-1060. PMID: 33726720

36. Layland B, et al. Māori health disparities in New Zealand: A review for emergency physicians. N Z Med J. 2022;135(1554):74-82. PMID: 35252342

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Quick Reference Card

eFAST Views and Positive Findings

Diagnostic Accuracy Summary

Key Decision Rules

• Positive eFAST + Unstable → Immediate operative intervention (OR)
• Negative eFAST + High suspicion → Serial exams OR CT if stable
• Absent cardiac activity + Arrest → Consider termination if no reversible cause
• Pneumothorax → Chest tube if large/symptomatic, observation if small/stable