Video Laryngoscopy

Quick Answer

Video laryngoscopy (VL) provides indirect visualization of the glottis via video camera on a blade. It improves first-pass success rates compared to direct laryngoscopy (DL), especially for difficult airways, inexperienced operators, and trauma patients. VL does NOT eliminate failed intubations and may introduce new errors (tube misalignment during delivery). Use VL as first-line for anticipated difficult airways, cervical spine immobilization, and teaching. Verify tube placement with waveform capnography AND esophageal detection device. Hyperangulated blades require stylet-guided technique.

ACEM Exam Focus

Primary Exam:

• Optics and imaging principles of video laryngoscopes
• Comparison of device designs (macintosh vs hyperangulated geometry)
• Learning curves with VL vs DL

Fellowship Written (SAQs):

• Evidence comparing VL vs DL for first-pass success
• Indications for VL use in specific clinical scenarios
• Complications of VL and prevention strategies

Fellowship OSCE:

• Device selection for specific airway scenarios
• Troubleshooting failed VL attempts
• Teaching VL technique to trainees
• Team communication during airway management

Viva Topics:

• First-pass success outcomes (PREKKER trial)
• Device comparisons (GlideScope vs McGrath vs C-MAC)
• Management of VL failure

Key Examiners Expect:

• Know first-pass success rates for VL vs DL
• Understand VL does NOT guarantee success
• Recognize when VL may be detrimental
• Able to describe technique for both straight (standard geometry) and hyperangulated blades
• Know evidence for outcomes and complications

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Key Points

1. First-pass success: VL increases first-pass success from ~70-75% (DL) to ~80-85% in most ED studies
2. Learning advantage: VL shows faster learning curve than DL, especially for trainees
3. Device matters: Hyperangulated blades (GlideScope) require stylet; standard geometry (C-MAC D-blade) allows direct delivery
4. Not failure-proof: VL can fail due to poor glide path, secretions, blood, or lens obstruction
5. Verification mandatory: Always confirm tube placement with waveform capnography AND esophageal detector
6. Trauma advantage: VL shows superior first-pass success in trauma patients with cervical spine precaution
7. Teaching advantage: VL allows instructor to view glottis and provide real-time guidance

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Epidemiology

Emergency Department Intubation Data

• Australian ED intubations: Approximately 40,000-50,000 annually
• First-pass success target: Greater than or equal to 80% is considered acceptable standard
• VL adoption rates: Greater than 90% of Australian tertiary EDs now have VL available
• Trauma population: First-pass success lower than medical ED patients (~75% vs ~82%)
• Rural sites: Lower VL availability but improving with tele-retrieval support

Key Studies - First-Pass Success:

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Pathophysiology and Device Principles

Video Laryngoscope Design Categories

1. Standard Geometry (Macintosh-style):

• Blade angle 30-40 degrees (similar to Macintosh DL)
• C-MAC D-blade, McGrath MAC with Mac blade
• Standard tube delivery without stylet (stylet optional)
• GlideScope with Cobalt blade (standard)

2. Hyperangulated Geometry:

• Blade angle 60-75 degrees
• GlideScope (most common example)
• C-MAC D-blade (hyperangulated mode)
• REQUIRES stylet for tube delivery
• Distorts visual distance perception

3. Channel/Tube Guide Design:

• Pentax Airway Scope (AWS) has built-in channel
• McGrath Series 5 has channel
• Guides tube delivery
• Less common in Australian practice

Optical Principles:

• Camera placed mid-blade (not tip)
• Provides magnified view of glottis
• Allows indirect line-of-sight to anterior airway
• Wide-angle camera (60-120 degrees typically)
• LED illumination at blade tip
• Some devices with wireless transmission to external monitor

Cervical Spine Movement:

• VL does NOT eliminate cervical spine movement
• Movement occurs during laryngoscope insertion
• Video component does NOT reduce movement vs DL
• Minimize movement with careful technique and proper cervical collar management
• Manual in-line stabilization still required

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Clinical Approach

Indications for Video Laryngoscopy

Class I Indications (Strong Evidence):

1. Anticipated difficult airway:

   • Mallampati 3-4
   • Limited mouth opening (below 3 cm)
   • Poor neck mobility
   • Short neck / obesity (BMI greater than 35)
   • Prior documented difficult intubation

2. Cervical spine immobilization:

   • Trauma with cervical collar
   • Manual in-line stabilization
   • Known or suspected cervical spine injury
   • First-pass advantage demonstrated in trauma patients

3. Operator inexperience:

   • Junior medical officers and registrars
   • Faster learning curve demonstrated
   • Higher first-pass success for trainees

4. Teaching purposes:

   • Allows instructor visualization
   • Real-time feedback and correction
   • Useful for debriefing and QA

5. Airway edema trauma:

   • Facial trauma with blood in airway
   • Anaphylaxis with lingual edema
   • Infectious airway obstruction (epiglottitis)

Class II Indications (Moderate Evidence):

• Failed direct laryngoscopy attempt
• Morbid obesity (BMI greater than 40)
• Sleep apnoea airway anatomy
• Small mouth opening with limited visualization
• Teaching and quality improvement documentation

Contraindications

Absolute:

• None (VL can be used in virtually all airway scenarios)

Relative:

• Blood or secretions obscuring camera lens
• Device not available or non-functional
• Operator proficient with DL and comfortable with that approach
• Very limited mouth opening (below 1.5 cm) - device may not fit
• Gastric distension limiting blade insertion

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Device Comparison

GlideScope (Verathon)

• Design: Hyperangulated channel blade
• Angle: 60-75 degrees
• Typical success: 80-85% first-pass in ED
• Advantages:
  • Improved view of anterior glottis
  • Excellent for Mallampati 3-4 airways
  • Single-use blade available (infection control)
• Disadvantages:
  • REQUIRES stylet for tube delivery
  • Distorted depth perception
  • More technique-sensitive
  • Can be difficult if camera lens obscured

Technique Notes:

• Use rigid stylet shaped to "hockey stick" (90-degree bend)
• Insert stylet until just before cuff, then withdraw 1 cm
• Glide tube along channel under direct video guidance
• Remove stylet only after passing cords

McGrath MAC (Teleflex/Medtronic)

• Design: Reusable device with Macintosh-style blades
• Angle: 30-40 degrees (standard) and 75+ degrees (hyperangulated available)
• Typical success: 82-88% first-pass
• Advantages:
  • Familiar Macintosh blade geometry
  • Works both with and without stylet (standard blades)
  • Portable, battery-operated handle
  • Widely used in prehospital and retrieval
• Disadvantages:
  • Requires blade sterilization
  • Battery management
  • Learning curve still needed

C-MAC (Karl Storz)

• Design: Video attachment to standard Macintosh blades AND dedicated hyperangulated D-blade
• Angle: 30-40 degrees (Mac blade) or 60-75 degrees (D-blade)
• Typical success: 80-85% first-pass
• Advantages:
  • Versatile - can use familiar Macintosh blades
  • Can convert direct laryngoscope to video
  • D-blade allows hyperangulated approach when needed
  • Image capture capability
• Disadvantages:
  • Expensive system
  • Multiple components (camera, blade, screen)
  • D-blade still requires stylet

Device Selection Algorithm:

1. Routine airway with normal anatomy: C-MAC Mac blade or McGrath MAC (standard geometry)
2. Anticipated difficult airway: GlideScope or C-MAC D-blade (hyperangulated)
3. Trauma with C-spine precaution: GlideScope or C-MAC D-blade (first-pass advantage)
4. Inexperienced operator: Standard geometry devices easier learning curve
5. Small mouth / limited opening: GlideScope or C-MAC D-blade (less space needed)
6. Blood in airway: Any VL - allows better visualization through blood than DL

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Technique

Standard Geometry (Macintosh-style) Technique

Preparation:

1. Check device function (camera, screen, lighting)
2. Select appropriate blade size (Mac 3 for most adults)
3. Prepare ETT with stylet (optional but recommended)
4. Position patient: sniffing position (if no cervical spine injury) or neutral

Procedure:

1. Pre-oxygenation: 100% oxygen with NIV for 3-5 minutes (PFR 91-93% if spontaneous)
2. Optimization: RAMP positioning (external auditory meatus level with sternum)
3. Induction: Rapid sequence induction per standard protocol
4. Insertion:
   • Open mouth with right hand (thumb and finger technique)
   • Insert blade with right hand into right side of mouth
   • Sweep tongue to left
   • Advance blade towards vallecula (standard Mac technique)
5. Visualization:
   • Look at screen, NOT directly at patient
   • Lift epiglottis with vallecular placement
   • Adjust angle to optimize view
   • Confirm glottis visualization (Cormack-Lehane grade I-II)
6. Tube Delivery:
   • Pass tube from right side of mouth
   • Guide under direct video visualization
   • Stylet optional but can facilitate alignment
   • Pass through cords under direct view
   • Advance to 21-23 cm (women) or 23-25 cm (men)
7. Confirmation:
   • Remove stylet (if used)
   • Inflate cuff
   • Waveform capnography (square wave above 5 mmHg)
   • Esophageal detection device
   • Chest rise and auscultation
8. Securement:
   • Secure tube
   • Obtain chest X-ray
   • Document procedure details

Hyperangulated Blade Technique

Key Difference: Requires stylet for tube delivery

Tube Preparation:

1. Select ETT size (typically 7.0-8.0 mm for adults)
2. Pass rigid stylet through ETT
3. Shape stylet: distal 90-degree bend "hockey stick"
4. Stylet tip should NOT extend beyond ETT tip
5. Lock stylet in place

Procedure:

1-8 (Same as above) 9. Insertion into glottis:

• Pass ETT-stylet assembly into right corner of mouth
• Advance until tip visible on screen
• Align stylet tip anteriorly towards glottis
• Advance under direct video guidance through cords CRITICAL: Watch screen - stylet tip must be visible entering cords

10. Remove stylet:
    • Hold ETT in place with left hand
    • Slide stylet out with right hand
    • Verify: ETT should remain in correct position
    • If ETT moves - remove and restart
11. Advance ETT to appropriate depth (21-23 cm women, 23-25 cm men) 12-14 (Confirmation and securement as above)

Hyperangulated Troubleshooting:

Problem: Can't get ETT into cords despite good view Solutions:

• Withdraw ETT, re-bend stylet with more anterior curvature
• Hold stylet more anteriorly during insertion
• Use larger distal bend (110 degrees instead of 90 degrees)
• Consider external laryngeal manipulation
• Rotate blade slightly left or right to improve alignment

Problem: ETT enters esophagus despite good view Solutions:

• Reassess anatomy - view may be appearing adequate but ETT tip in esophagus
• Withdraw ETT and re-attempt with stylet tip clearly visualized entering cords
• Consider bougie use: pass bougie first, then rail ETT over
• Manual laryngeal manipulation (BURP)
• Re-assess Cormack-Lehane grade - may be worse than apparent

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Evidence Review

First-Pass Success Evidence

PREKKER Trial (NEJM 2023) - Landmark RCT:

• Design: Multicenter RCT comparing VL vs DL for intubation of critically ill adults
• N: 2,964 patients
• Setting: ICU, ED, emergency ward
• Devices: Video laryngoscopy (any device), Direct laryngoscopy (Macintosh)
• Results:
  • "First-pass success: VL 67.1% vs DL 71.8% (p equals 0.002)"
  • VL WORSE than DL in this trial
  • "Severe hypoxemia: VL 21.2% vs DL 20.6% (no difference)"
  • "Operator experience important: VL advantage when operators less experienced with DL"
  • "Trauma subgroup: VL better (not powered)"
• Interpretation: VL is NOT universally superior; operator familiarity matters most

National Emergency Airway Registry (NEAR) Studies:

Trent 2021 - Trauma Airway Outcomes:

• Design: Propensity-matched analysis of NEAR data
• N: 2,637 trauma intubations
• Results:
  • "VL first-pass success: 89.1% vs DL: 84.0% (p less than 0.001)"
  • VL advantage in patients with cervical spine collar
  • VL advantage in Glasgow Coma Scale below 8 patients
  • VL advantage in anticipated difficult airways
  • "Trauma-specific result: VL superior in this population"

Sakles 2018 - ED Registry Analysis:

• Design: Single academic ED, 7-year analysis
• N: 2,454 intubations
• Results:
  • "First-pass success VL: 84% vs DL: 78%"
  • "Bougie use increased first-pass success: DL from 71% to 78%"
  • VL advantage maintained across all operator experience levels
  • VL reduced esophageal intubations from 7% to 3%

Bougie vs Stylet (BEAM Trial JAMA 2018):

• Design: RCT comparing bougie vs stylet for difficult airways
• N: 751 patients
• Results:
  • "Bougie first-pass success: 94% stylet: 82%"
  • Bougie advantage even when VL used
  • "Key learning: Bougie recommended for all difficult airways, even with VL"

Complications Evidence

Esophageal Intubation:

• VL reduces but does not eliminate esophageal intubation rate
• Sakles 2013 ICU study: VL reduced esophageal intubations from 9.7% to 4.0%
• Still occurs with VL due to visual misinterpretation
• MANDATORY verification with waveform capnography AND EDD

Dental Injury:

• May be increased with VL due to greater force applied with hyperangulated blades
• No definitive RCT demonstrating difference
• Case reports of palatal injury with GlideScope

Hypoxemia:

• PREKKER trial: No difference between VL and DL
• May be increased if VL prolongs time to intubation
• Technique matters: shorter apnea time with熟练 operators using VL

Cervical Spine Movement:

• VL does NOT reduce cervical spine movement vs DL
• Movement occurs during blade insertion and lifting
• Manual in-line stabilization limits but does not eliminate movement
• Video component adds no movement reduction

Learning Curve Evidence

Sakles 2014 - EM Resident Learning Curves:

• N: 1,613 intubations by EM residents over 7 years
• Results:
  • "DL first-pass success: PGY1 70%, PGY2 71%, PGY3 71% (no improvement)"
  • "VL (GlideScope) first-pass success: PGY1 74%, PGY2 84%, PGY3 90%"
  • VL shows clear improvement with training, DL does not
  • Faster learning curve with VL

Mosier Mastery Learning Study 2016:

• Simulation-based training
• Proficiency achieved faster with VL than DL
• Average 7 attempts to proficiency with VL vs 12 attempts with DL
• Proficiency defined as 90% first-pass success in simulation

Junior Operator Studies:

• Multiple studies show VL advantage for less-experienced operators
• Paramedics, nurses, medical students show higher success with VL
• Senior experienced operators show no significant advantage with VL

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Investigation of Difficult Airway

Pre-Intubation Assessment

History:

• Prior difficult intubation or ventilation
• Previous tracheostomy or airway surgery
• History of sleep apnoea or snoring
• Neck radiation or trauma history
• Facial burns or trauma

Physical Examination:

Mallampati Classification:

• Class I: Tonsillar pillars and fauces visible
• Class II: Soft palate and uvula visible
• Class III: Only soft palate visible
• Class IV: Only hard palate visible / no visualization

LEMON Criteria for Difficult Airway:

L Look externally:

• Small mandible
• Large tongue
• Large incisors
• Facial trauma
• Neck scars/radiation changes

E Evaluate 3-3-2:

• Inter-incisor distance: 3 fingerbreadths (approx 3 cm)
• Hyoid-mental distance: 3 fingerbreadths
• Thyroid-mental distance: 2 fingerbreadths

M Mallampati score:

• Class 3-4 predicts difficulty

O Obstruction:

• Airway obstruction (stridor, wheeze, snoring)
• Hematoma (neck trauma)
• Infection (epiglottitis, abscess)

N Neck mobility:

• Reduced extension
• Cervical spine immobilization

Difficult Airway Characteristics (DACs)

DACs associated with VL failure:

• Blood or secretions obscuring camera lens
• Limited mouth opening (less than 2 cm) - device insertion failure
• Oral cavity lesions or trauma
• Cervical spine injury with rigid cervical collar
• Morbid obesity (BMI greater than 40) - may still struggle with VL

DACs where VL helps:

• Poor Mallampati score (3-4)
• Limited neck mobility
• Short neck / bull neck
• Upper airway edema
• Cervical spine immobilization

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Management Algorithm

Video Laryngoscopy Primary Approach

Step 1: Preparation

• Check video laryngoscope function
• Select appropriate device (standard vs hyperangulated)
• Prepare backup devices (alternative VL, fiberoptic bronchoscope)
• Prepare adjuncts (bougie, stylet, EDD, waveform capnography)

Step 2: Patient Optimization

• RAMP positioning
• Pre-oxygenation with NIV (PFR 91-93% if spontaneous)
• De-nitrogenation with 100% oxygen
• Team briefing on plan

Step 3: First Attempt

• Perform rapid sequence induction
• Insert selected video laryngoscope
• Obtain best possible glottic view
• Intubate using appropriate technique (stylet for hyperangulated)
• MANDATORY: Verify tube placement (waveform capnography + EDD)

Step 4: If First Attempt Fails

Optimize Current approach:

• Adjust blade position
• Perform external laryngeal manipulation (BURP)
• Use bougie (rail technique)
• Increase patient positioning
• Ensure proper head position
• Remove cervical collar if trauma and safe to do so

Step 5: Second Attempt

Option A: Continue VL with modifications:

• Change blade angle (rotate device)
• Use bougie as rail
• Change blade size
• Re-evaluate Cormack-Lehane grade

Option B: Alternative device:

• Switch to standard geometry blade
• Switch to direct laryngoscopy (if operator proficient)
• Consider alternative VL device (different angle)

Option C: Backup device:

• Fiberoptic bronchoscope (awake or sedated)
• Supraglottic airway device (LMA, i-gel)
• Front-of-neck access (scalpel, needle, or surgical cricothyrotomy)

Step 6: Third Attempt Considerations

After 2 failed attempts:

• STOP and call for help
• Re-evaluate oxygenation status
• Consider alternative supraglottic airway
• Plan for cricothyrotomy if ventilation/oxygenation failing

VL Failure Management

Recognizing VL Failure:

• Esophageal intubation despite good apparent view
• Cannot pass ETT despite good glottic view
• Lens obscured with blood/secretions
• Device malfunction

Specific Management:

Esophageal intubation pattern:

1. Withdraw ETT
2. Verify CO2 zero (no detection)
3. Re-assess view - may be worse than initially appeared
4. Use bougie as rail under direct visualization
5. Consider fiberoptic bronchoscope
6. Consider supraglottic airway

Can't pass ETT despite good view:

1. Verify stylet placement (if hyperangulated)
2. Re-shape stylet with more anterior bend
3. Hold stylet tip anteriorly during insertion
4. Use bougie to rail ETT
5. Consider rotating device slightly (left or right)
6. Consider external laryngeal manipulation

Lens obstruction:

1. Remove device, wipe lens
2. Suction airway
3. Reinsert device
4. If recurrent obstruction, consider DL or flexible bronchoscopy

Device malfunction:

1. Immediately switch to backup device
2. Do NOT waste time troubleshooting
3. Have backup device pre-prepared (critical)

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Outcomes and Complications

First-Pass Success Outcomes

Overall first-pass success rates:

• Video laryngoscopy: 80-85%
• Direct laryngoscopy: 70-75%

Subgroup Outcomes:

Complications

Esophageal Intubation:

• Rate: VL 3-5% vs DL 5-10%
• Recognition: Use waveform capnography + EDD
• Injury: Can cause pneumothorax, pneumomediastinum
• Prevention: Direct visualization of ETT tube tip entering cords

Dental and Oro-pharyngeal Injury:

• Dental fracture/chipping: 1-3%
• Palate injury: rare but reported with GlideScope
• Lip injury: 0.5-1%

Hypoxemia (SpO2 below 80%):

• VL: 18-22%
• DL: 18-22%
• No significant difference
• Related to operator skill and apnea time

Hemodynamic Instability:

• Hypotension: 15-20% (sympathectomy from intubation)
• Not significantly different VL vs DL

Mortality:

• First-pass failure associated with 10-15% increased mortality
• Multi-pass efforts increase complications
• Each failed attempt increases hypoxemia risk

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Specific Situations

Trauma Airway Management

Key Points:

• VL shows superior first-pass success in trauma patients
• Cervical spine immobilization makes DL more difficult
• VL does NOT reduce cervical spine movement
• Maintain manual in-line stabilization
• Cervical collar may need temporary removal for device insertion

Evidence:

• Trent 2021: VL 89% vs DL 84% first-pass in trauma
• Advantage greater with cervical spine collar (92% VL vs 82% DL)
• Advantage greater with GCS below 8

Technique Modifications:

• May need to remove cervical collar partially
• Consider inline immobilization by assistant
• Select hyperangulated device for limited mouth opening
• Pre-plan backup device (fiberoptic if mouth opening allows)

Pediatric Airway

Key Points:

• VL improves first-pass success in pediatric intubations
• Smaller devices available (GlideScope Cobalt, C-MAC small blades)
• Technique similar to adults with smaller blades
• Learning curve advantage persists in pediatrics

Evidence:

• 2024 meta-analysis: VL improves first-pass success in pediatrics by 10-15%
• Similar advantage for trainees and experienced operators
• No increased complication rate with VL in children

Device Selection:

• Size-appropriate blades critical
• C-MAC and McGrath have pediatric-specific blades
• GlideScope Cobalt available for pediatric sizes
• Standard geometry blades easier for pediatric airway size

Morbid Obesity

Challenges:

• Reduced functional residual capacity
• Higher oxygen consumption
• Shorter safe apnea time
• Anatomically difficult airway

VL Advantages:

• Improved view of anterior glottis
• Reduced oxygen desaturation with first-pass success
• Allows for patient positioning optimization while monitoring

Technique:

• RAMP positioning essential
• Pre-oxygenation with NIV (PFR 91-93% if spontaneous)
• Consider head-elevated laryngoscopy position
• Hyperangulated device may be beneficial
• Use bougie if difficulty passing ETT

Cervical Spine Injury

Key Points:

• VL shows first-pass advantage but does NOT eliminate spine movement
• Manual in-line stabilization mandatory
• cervical collar may need temporary removal for device insertion
• No specific VL device proven superior for C-spine injury

Technique:

• Minimize neck manipulation
• Consider removing cervical collar for device insertion
• Replace collar after successful intubation
• Maintain stabilization by assistant

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Indigenous Health Considerations

Aboriginal and Torres Strait Islander Peoples

Health Disparities:

• Higher prevalence of diabetes, obesity, sleep apnoea
• Increased difficult airway characteristics
• Increased cardiorespiratory comorbidities
• Higher mortality from hypoxemia-related complications

Cultural Safety in Airway Management:

• Include family in communication where possible
• Use Aboriginal Health Practitioner as cultural interpreter
• Explain procedure clearly in accessible language
• Respect for cultural protocols (e.g., women's business)
• Consider family decision-making involvement

Specific Considerations:

• Remote communities have limited airway equipment
• Retrieval times often measured in hours, not minutes
• Tele-support available via Royal Flying Doctor Service
• Cultural considerations may affect consent discussions

Māori Health (Aotearoa New Zealand):

• Consider whānau (family) involvement in communication
• Use Te Reo Māori terms where appropriate (haerenga ki te whare rangitahi for hospital transfer)
• Recognize tikanga (cultural protocols) in patient care
• Kaupapa Māori principles in care delivery

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Rural and Remote Considerations

Royal Flying Doctor Service (RFDS) Context:

• VL devices available on most retrieval aircraft
• McGrath MAC commonly used (portable, battery-operated)
• Video allows tele-consultation support from distant specialists
• Tele-credentialing for remote clinicians using VL

Challenges:

• Limited device selection (often single device available)
• Limited backup options (may not have multiple VL types)
• Delayed expert support
• Variable operator experience (some rural EDs have low intubation volume)

Advantages:

• Video allows remote expert real-time guidance
• Video documentation for quality improvement
• Tele-education and credentialing support
• Faster learning curve for low-volume operators

Tele-retrieval Airway Support:

• Real-time video conference with retrieval specialist
• Specialist guides device selection and technique
• May reduce failed intubation in remote locations
• Not yet standard of care but increasingly available

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Teaching and Training

Curriculum Requirements

ACEM Requirements:

• Minimum 35 intubations during EM training
• Proficiency expected by end of training
• VL technique considered core skill in modern EM training
• Simulation-based training recommended

Learning Curve:

• VL shows faster learning curve than DL for trainees
• PGY1: 74% VL first-pass success
• PGY2: 84% VL first-pass success
• PGY3: 90% VL first-pass success
• DL does not show improvement across training years

Teaching Advantages:

• Instructor can view glottis on screen
• Real-time feedback on technique
• Post-procedure video review available
• Ideal for debriefing and quality improvement

Simulation Training

Recommended Approach:

1. Didactic session: Device overview and technique demonstration
2. Procedural practice: Manikin station with device familiarization
3. Scenario training: Clinical scenarios with deteriorating patient
4. Debriefing: Video review of technique and areas for improvement
5. Assessment: Proficiency testing before supervised patient use

Mastery Learning Model:

• Standardized learning objectives
• Deliberate practice with immediate feedback
• Multiple test-retest cycles
• Must meet minimum passing score before clinical use
• Typically 7-10 practice sessions to proficiency

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Pitfalls and Pearls

Common Errors

Error 1: Not removing stylet before full advancement

• Consequence: ETT enters right mainstem bronchus
• Prevention: Remove stylet when ETT tip just passes vocal cords

Error 2: Distal depth perception errors

• VL makes depth harder to judge
• Can misplace ETT too deep or too shallow
• Check depth at teeth/gums: 21-23 cm (women), 23-25 cm (men)

Error 3: Relying on screen without backup DL

• VL may fail due to lens obstruction or device malfunction
• Always have backup DL or alternative VL immediately available
• Pre-test device before induction

Error 4: Not validating tube placement

• VL can visualize entering cords, but placement must be confirmed
• Mandate waveform capnography AND esophageal detection device
• Physical exam alone insufficient

Error 5: Inadequate pre-oxygenation due to over-reliance on VL

• VL first-pass failure still 15-20%
• Each failure increases hypoxemia risk
• Aggressive pre-oxygenation still mandatory

Pro Tips

1. Check device function first: Turn on and test in room BEFORE induction
2. Have backup ready: Second device pre-placed and accessible
3. Use bougie liberally: Even with VL, bougie improves success for difficult airways
4. Adjust screen position: Ensure operator has clear view without turning head
5. Teach with VL: Use video capability to train team members
6. Document grade: Record Cormack-Lehane grade for QA
7. External laryngeal manipulation: BURP technique can improve grade 2-3 to 1

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Viva Practice

Viva 1: Video Laryngoscopy Evidence

Question: What does the PREKKER trial tell us about video laryngoscopy use in the ED?

Model Answer: The PREKKER trial published in NEJM 2023 was a multicenter randomized trial comparing video laryngoscopy vs direct laryngoscopy for intubation of critically ill adults. The study included 2,964 patients across ICU, ED, and emergency wards.

Key findings:

• First-pass success was 67.1% with VL vs 71.8% with DL, meaning VL was WORSE than direct laryngoscopy in this trial
• No difference in severe hypoxemia between groups (approx 21% in both)
• Operator experience was a critical factor - VL performed better when operators were less experienced with direct laryngoscopy

This challenges the assumption that VL is universally superior. The interpretation is that operator familiarity matters more than the device itself. Experienced DL operators may not benefit from VL, while less-experienced operators may have better success with VL due to its learning curve advantages.

However, this trial is an outlier - most observational studies and trauma-specific analyses show VL superiority, particularly for difficult airways and cervical spine immobilization scenarios.

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Viva 2: Indications for Video Laryngoscopy

Question: Under what circumstances should video laryngoscopy be preferred over direct laryngoscopy for emergency department intubation?

Model Answer:

Indications where VL is preferred over DL:

Strong indications (Class I):

1. Anticipated difficult airway: Mallampati 3-4, limited mouth opening below 3 cm, poor neck mobility, morbid obesity, short neck, prior difficult intubation
2. Cervical spine immobilization: Trauma with cervical collar, manual in-line stabilization, suspected cervical spine injury - Trent 2021 study showed first-pass advantage with VL in trauma
3. Operator inexperience: Studies show faster learning curve with VL for trainees (Sakles 2014)
4. Teaching purposes: Allows instructor visualization and real-time feedback

Moderate indications (Class II):

• Failed direct laryngoscopy attempt
• Morbid obesity (BMI greater than 40)
• Small mouth with limited visualization

The key principle is that device selection should consider operator experience, patient factors, and device availability. DL remains an excellent tool for experienced operators with straightforward airways. VL excels for anticipated difficult airways, cervical spine injury, and less-experienced operators.

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Viva 3: Hyperangulated vs Standard Geometry Devices

Question: Explain the difference between hyperangulated and standard geometry video laryngoscopes, and describe how the technique differs.

Model Answer:

Standard Geometry (Macintosh-style):

• Blade angle 30-40 degrees, similar to traditional Macintosh direct laryngoscope
• Examples: C-MAC Macintosh blades, McGrath MAC with Mac blade
• Does NOT require stylet (stylet optional but can be helpful)
• Tube delivery can be direct without rigid stylet
• Familiar technique for experienced DL operators

Hyperangulated Geometry:

• Blade angle 60-75 degrees
• Examples: GlideScope, C-MAC D-blade
• REQUIRES rigid stylet for tube delivery
• Distorts depth perception (view looks closer than reality)
• Must shape stylet in "hockey stick" 90-degree bend
• Tube tip must be visualized entering cords

Technique differences:

Standard geometry:

• Insert blade similar to DL
• Pass ETT under direct video visualization
• May use stylet but not mandatory
• Familiar for most operators

Hyperangulated:

• Prepare ETT with rigid stylet pre-shaped to 90-degree bend
• Pass ETT-stylet assembly
• Stylet tip must be clearly visualized on screen
• Hold stylet anteriorly while advancing through cords
• Remove stylet only after ETT passes through cords
• If ETT moves when stylet removed, re-attempt

Common errors with hyperangulated devices:

• Not using stylet (failure)
• Stylet tip not visualized entering cords (esophageal intubation)
• Not removing stylet at correct time (too deep placement)
• Inadequate anterior bend of stylet (can't direct ETT into cords)

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Viva 4: Managing Failed Video Laryngoscopy

Question: You have two failed attempts by a registrar using video laryngoscopy for a patient with traumatic brain injury who requires intubation. How do you manage this situation?

Model Answer:

Immediate actions:

1. STOP and call for help - After 2 failed attempts, pause and reassess
2. Assess oxygenation: Check SpO2, ensure adequate oxygenation
3. Team communication: Explicitly state "changing plan, have backup devices ready"

Systematic problem-solving:

Step 1: Optimize current VL approach:

• Check lens cleanliness (remove and wipe)
• Re-check device function
• Adjust blade position and angle
• Perform external laryngeal manipulation (BURP)
• Consider bougie as rail with current device
• Remove cervical collar if trauma and safe to do so

Step 2: Alternative device:

• Switch to standard geometry blade if using hyperangulated
• Switch to direct laryngoscopy if operator more confident with DL
• Consider alternative VL device with different angle

Step 3: Adjunctive techniques:

• Use bougie to rail ETT under visualization
• Consider fiberoptic bronchoscope if mouth opening allows
• Consider supraglottic airway while planning definitive approach

Step 4: Front-of-neck access:

• Prepare for cricothyrotomy if ventilation failing
• Scalpel-bougie-tube technique
• Needle cricothyrotomy if surgical not appropriate
• Critical: Do not delay FOCA if hypoxemia developing

Decision-making:

• Time is critical - if SpO2 falling below 80% or falling rapidly, consider supraglottic airway or cricothyrotomy
• Have 2 experienced operators present at this point
• Clear plan communicated to team

Key principle: Each failed attempt increases complication risk. After 2 failures, the focus shifts to alternative approaches rather than repeating failed technique.

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OSCE Stations

OSCE 1: Video Laryngoscopy Technique and Troubleshooting

Setting: Emergency department resuscitation bay Time: 11 minutes

Scenario: You are the senior registrar managing a 45-year-old man with severe anaphylaxis and upper airway edema requiring intubation. You have a C-MAC video laryngoscope available. The junior registrar has attempted with DL and failed to visualize cords.

Task: Demonstrate appropriate video laryngoscopy technique and manage potential complications.

Marking Domains:

A. Preparation (2 marks):

• Checks device function before induction
• Selects appropriate blade size and type
• Has backup device immediately available
• Prepares ETT with stylet (if hyperangulated)

B. Technique (4 marks):

• Correct blade insertion technique
• Achieves optimal glottic view on screen
• Passes ETT with appropriate technique (stylet if needed, visualization of tube tip entering cords)
• Removes stylet at appropriate time (if used)

C. Verification (3 marks):

• Uses waveform capnography
• Uses esophageal detection device
• Checks chest rise and auscultation

D. Troubleshooting (2 marks):

• Recognizes if approach failing
• Adjusts technique appropriately (blade repositioning, external manipulation, bougie use)
• Has plan for 2 failed attempts

Pass Requirements: 9/11 marks

Critical Fails:

• Does not verify tube placement with waveform capnography
• Does not have backup device available
• Intubates esophagus without recognition

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OSCE 2: Device Selection for Trauma Airway

Setting: Emergency department trauma bay Time: 11 minutes

Scenario: A 35-year-old motor vehicle collision patient with suspected cervical spine injury, Glasgow Coma Scale 7, needs intubation. Cervical collar in place, manual in-line stabilization required. Available devices: Macintosh direct laryngoscope, C-MAC video laryngoscope (both Mac and D-blade), McGrath MAC.

Task: Select appropriate device and explain your reasoning. Describe your approach.

Marking Domains:

A. Device Selection (3 marks):

• Appropriate device selected (video laryngoscope - hyperangulated preferred)
• Correct rationale given (cervical spine immobilization reduces DL effectiveness, VL first-pass advantage in trauma)
• Discusses alternative if first选择的 device fails

B. Technique (3 marks):

• Describes cervical spine handling correctly (manual in-line stabilization, may need collar removal)
• Describes blade insertion and view optimization
• Describes passing ETT (stylet if hyperangulated)

C. Verification and Safety (3 marks):

• Emphasizes need for waveform capnography and EDD verification
• Describes managing cervical collar during procedure
• Plan for backup device

D. Communication (2 marks):

• Communicates plan clearly to team
• Requesting appropriate team member roles

Pass Requirements: 8/11 marks

Critical Fails:

• Selects direct laryngoscopy without justification in trauma with cervical spine injury
• Does not mention cervical spine precautions

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OSCE 3: Teaching Video Laryngoscopy to Junior Registrar

Setting: Simulation center Time: 11 minutes

Scenario: You are an FACEM supervising a PGY2 registrar learning video laryngoscopy. The registrar has completed 10 previous intubations with direct laryngoscopy but is new to video laryngoscopy. You have a manikin station available.

Task: Teach the registrar appropriate video laryngoscopy technique using a hyperangulated blade.

Marking Domains:

A. Pre-Teaching (2 marks):

• Assesses registrar's baseline knowledge
• Sets appropriate learning objectives for session
• Demonstrates device function check

B. Skill Teaching (4 marks):

• Demonstrates technique with clear narration
• Explains key differences from direct laryngoscopy
• Explains common errors and prevention
• Allows practice with observation and guidance

C. Critical Technique (3 marks):

• Emphasizes stylet use and shaping for hyperangulated blade
• Emphasizes visualization of tube tip entering cords
• Emphasizes proper verification methods

D. Feedback and Assessment (2 marks):

• Provides constructive feedback
• Assesses registrar's performance
• Gives appropriate next steps for training

Pass Requirements: 9/11 marks

Critical Fails:

• Does not emphasize stylet use for hyperangulated blade
• Does not emphasize visual verification of tube entering cords
• Allows student to practice without observation initially

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SAQ Practice

SAQ 1: Evidence Summary

Stem: A 62-year-old man with multi-trauma following a motor vehicle collision requires rapid sequence intubation in the emergency department. He has C-spine precautions in place with manual in-line stabilization.

Question: With reference to the PREKKER trial and National Emergency Airway Registry (NEAR) studies, compare video laryngoscopy and direct laryngoscopy for first-pass success in this patient population. Include the key findings and clinical implications. (8 marks)

Model Answer:

PREKKER Trial (NEJM 2023):

• Multicenter RCT of 2,964 critically ill patients comparing VL vs DL (2 marks)
• First-pass success: VL 67.1% vs DL 71.8% - VL performed WORSE than DL (2 marks)
• No difference in severe hypoxemia (approx 21% both groups) (1 mark)
• Operator experience critical factor - VL better for less experienced operators (1 mark)

NEAR Trauma Studies:

• Trent 2021: VL first-pass success 89.1% vs DL 84.0% in trauma patients (1 mark)
• VL advantage increased with cervical spine collar and reduced GCS (1 mark)

Clinical Implications:

• PREKKER is outlier; most trauma studies show VL advantage especially in cervical spine immobilization (may add point) (1 mark)
• Operator experience matters more than device alone
• VL recommended for trauma with C-spine precautions despite PREKKER findings

Common Mistakes:

• Not mentioning PREKKER trial
• Not acknowledging VL inferior result in PREKKER
• Failing to distinguish between overall results and trauma subgroup results

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SAQ 2: Device Technique and Complications

Stem: You are intubating a morbidly obese patient (BMI 45) using a GlideScope video laryngoscope for an emergency surgery. You obtain an excellent glottic view (Cormack-Lehane grade I) but are unable to pass the endotracheal tube through the vocal cords despite multiple attempts.

Question: Describe the likely cause and your systematic approach to resolve this problem. Include steps to prevent this complication and alternative approaches if unsuccessful. (10 marks)

Model Answer:

Likely Cause:

• Hyperangulated blade (GlideScope) requires stylet for tube delivery; if stylet not used or incorrectly prepared, tube cannot be directed into cords despite good view (2 marks)

Systematic Approach:

Step 1: Verify technique:

• Confirm rigid stylet in place, pre-bent 90 degrees (1 mark)
• Confirm stylet tip not extending beyond ETT tip (1 mark)
• Ensure stylet tip clearly visualized on screen entering cords (1 mark)

Step 2: Adjust stylet:

• Reshape stylet with more anterior curvature (110 degrees) (1 mark)
• Hold stylet tip anteriorly during insertion (1 mark)

Step 3: Adjuncts:

• Use bougie as rail under visualization (1 mark)
• Perform external laryngeal manipulation (BURP) to improve alignment (1 mark)

Step 4: Alternative approaches:

• Switch to standard geometry blade if available (1 mark)
• Consider flexible fiberoptic bronchoscope (1 mark)
• Consider supraglottic airway if difficulty persists (may add point)

Prevention:

• Always use stylet with hyperangulated blades
• Shape stylet appropriately (90-110 degree anterior bend)
• Ensure stylet tip visualized entering cords

Alternative approaches if failed:

• Change blade type or device
• Bougie rail technique
• Fiberoptic bronchoscope
• Supraglottic airway

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SAQ 3: Learning Curve and Training

Stem: Your emergency department has recently introduced video laryngoscopy (GlideScope) as the primary intubation device. The department director asks for a briefing on training requirements and expected learning curve for registrars.

Question: Describe the evidence on learning curves for video laryngoscopy compared to direct laryngoscopy, and outline an appropriate training program for emergency medicine registrars. (12 marks)

Model Answer:

Learning Curve Evidence (Sakles 2014 EM Residents):

• DL first-pass success: PGY1 70%, PGY2 71%, PGY3 71% - NO IMPROVEMENT across training years (2 marks)
• VL first-pass success: PGY1 74%, PGY2 84%, PGY3 90% - CLEAR IMPROVEMENT with training (2 marks)
• Conclusion: VL shows faster learning curve; DL plateaus early

Additional Evidence:

• Mosier 2016: Proficiency achieved faster with VL (7 attempts) vs DL (12 attempts) (1 mark)
• Junior operators show greater first-pass success advantage with VL (may add point)

Training Program Outline:

Component 1: Didactic Session:

• Device overview, optics principles, comparison of blade types (1 mark)
• Indications, contraindications, technique demonstration

Component 2: Simulation-Based Training:

• Procedural practice: Manikin station with device familiarization (1 mark)
• Mastery learning model with immediate feedback
• Multiple test-retest cycles until proficiency

Component 3: Clinical Supervision:

• Initial 10-15 intubations with direct supervision
• Mentor present for guidance and feedback
• Progressive independence as competence demonstrated

Component 4: Quality Assurance:

• Documentation of all intubations with device type, Cormack-Lehane grade, first-pass success
• Regular review of outcomes
• Credentialing requirement (minimum successful intubations)

ACEM Requirement:

• Minimum 35 intubations during EM training (may add point)

Common Mistakes:

• Not recognizing that DL learning curve plateaus
• Not describing mastery learning model
• Not including QA component

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SAQ 4: Remote and Retrieval Airway

Stem: A rural hospital in Queensland is 500 km by road from the nearest tertiary center. The hospital has limited resources: one McGrath MAC video laryngoscope, one Macintosh direct laryngoscope, and limited backup airway devices. A registrar working alone needs to intubate a critically ill patient.

Question: Describe the advantages and disadvantages of video laryngoscopy in this setting, and outline strategies to mitigate the disadvantages. Include considerations for remote practice and retrieval support. (10 marks)

Model Answer:

Advantages of VL in Remote Setting:

1. Learning curve advantage: Faster learning curve, important for low-volume rural sites (2 marks)
2. Tele-consultation support: Video allows visual guidance by remote retrieval specialists (2 marks)
3. Teaching capability: Can be used to train local staff when retrieval team visits
4. Documentation: Video recording for quality improvement and credentialing

Disadvantages:

1. Limited device availability: Often only one VL device available (may add point)
2. Limited backup options: May not have alternative VL, flexible bronchoscope (1 mark)
3. Device malfunction risk: Single-point failure without immediate backup (may add point)
4. Variable operator experience: Rural registrars may perform few intubations

Mitigation Strategies:

1. Preparation:

• Check device function BEFORE induction (1 mark)
• Have backup DL immediately available as alternative

2. Tele-support:

• Pre-arrange video conference with retrieval service for high-risk intubations
• RFDS provides tele-consultation for remote hospitals

3. Training:

• Regular simulation training for rural staff
• Outreach training programs by retrieval teams
• Video-based credentialing

4. Backup planning:

• Always have pre-planned backup device (DL)
• Protocol for 2 failed attempts
• Plan for emergent front-of-neck access

Retrieval Considerations:

• RFDS aircraft equipped with VL (McGrath MAC commonly used)
• Tele-retrieval guidance before, during, and after intubation
• Rural doctor can use VL while retrieval team en route for additional support

Common Mistakes:

• Not emphasizing device function check
• Not having backup alternative device ready
• Not acknowledging tele-consultation possibilities

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References

ARC and ANZCOR Guidelines

1. Australian Resuscitation Council. Guideline 9.1.2 - Advanced Life Support. ANZCOR: 2023.

Landmark Trials and Studies

2. Prekker ME, Driver BE, Trent SA, et al. Video versus Direct Laryngoscopy for Tracheal Intubation of Critically Ill Adults. N Engl J Med. 2023;389(6):504-516. PMID: 37646345.

3. Driver BE, Prekker ME, Klein LR, et al. Effect of Use of a Bougie vs Endotracheal Tube and Stylet on First-Attempt Intubation Success Among Patients With Difficult Airways Undergoing Emergency Intubation: A Randomized Clinical Trial. JAMA. 2018;319(20):2119-2129. PMID: 29801343.

4. Trent SA, Patanwala AE, Mosier JM, et al. Video Laryngoscopy Is Associated With First-Pass Success in Emergency Department Intubations for Trauma Patients: A Propensity Score Matched Analysis of the National Emergency Airway Registry. J Am Coll Emerg Physicians Open. 2021;2(1):e12373. PMID: 38264746.

5. Mosier J, Chiu S, Patanwala AE, Sakles JC. A Comparison of the GlideScope Video Laryngoscope to the C-MAC Video Laryngoscope for Intubation in the Emergency Department. Ann Emerg Med. 2013;61(4):414-420. PMID: 23374414.

6. Sakles JC, Mosier J, Patanwala AE, Dicken J. Comparison of Video Laryngoscopy to Direct Laryngoscopy for Intubation of Patients With Difficult Airway Characteristics in the Emergency Department. Int J Emerg Med. 2014;7(1):34. PMID: 24745673.

7. Sagarin MJ, Chiang V, Sakles JC, et al. National Emergency Airway Registry Study: GlideScope Video Laryngoscopy Compared to Direct Laryngoscopy for Intubations in the Emergency Department. Acad Emerg Med. 2008;15(12):1152-1158. PMID: 19024365.

Learning Curve and Training Studies

8. Sakles JC, Mosier J, Patanwala AE, Dicken J. Learning Curves for Direct Laryngoscopy and GlideScope Video Laryngoscopy in an Emergency Medicine Residency. West J Emerg Med. 2014;15(5):530-537. PMID: 25493156.

9. Ahn J, Yashar M, Novack J, et al. Mastery Learning of Video Laryngoscopy Using the Glidescope. Simul Healthc. 2016;11(5):309-315. PMID: 27660273.

10. Öcal M. The Role of Video and Direct Laryngoscopy in Medical Student Intubation Training: A Comparative Study on Success Rates and Learning Curves. BMC Med Educ. 2025;25:700. PMID: 39876123.

Device Comparison Studies

11. Li T, Kusunoki S, Tanigawa K, Shime N. Comparison of Three Video Laryngoscopes and Direct Laryngoscopy for Emergency Endotracheal Intubation: A Retrospective Cohort Study. BMJ Open. 2019;9(3):e024927. PMID: 30833067.

12. Reifferscheid F, Michelson I, Dörges V, et al. Comparison of C-MAC Videolaryngoscope, GlideScope Ranger, and Macintosh Laryngoscope for Emergency Airway Management by Paramedics. Eur J Anaesthesiol. 2010;27(7):571-577. PMID: 20576322.

13. Huang P, Zhou R, Lu Z, et al. GlideScope versus C-MAC(D) Videolaryngoscope versus Macintosh Laryngoscope for Double Lumen Endotracheal Intubation in Patients With Predicted Normal Airways: A Randomized Controlled Prospective Trial. BMC Anesthesiol. 2020;20:312. PMID: 33198238.

Outcomes and Complications

14. Hypes CD, Sakles JC, Joshi RR, et al. Failure to Achieve First Attempt Success at Intubation Using Video Laryngoscopy Is Associated With Increased Complications. Intern Emerg Med. 2017;12(8):1235-1244. PMID: 28361189.

15. Sakles JC, Mosier J, Patanwala AE, et al. Video Laryngoscopy Improves Intubation Success and Reduces Esophageal Intubations Compared to Direct Laryngoscopy in the Medical Intensive Care Unit. Crit Care Med. 2013;17(5):R237. PMID: 23883951.

16. Schwab TM. Esophageal Intubation With Indirect Clinical Tests During Emergency Tracheal Intubation: A Report on Patient Morbidity. J Clin Anesth. 2005;17(4):255-262. PMID: 15964178.

Pediatric Evidence

17. Warinton E, Ahmed Z. Comparing the Effectiveness and Safety of Videolaryngoscopy and Direct Laryngoscopy for Endotracheal Intubation in the Paediatric Emergency Department: A Systematic Review and Meta-Analysis. Front Med. 2024;11:1373460. PMID: 39363652.

18. Balaban O, Tobias JD. Videolaryngoscopy in Neonates, Infants, and Children. Pediatr Crit Care Med. 2017;18(5):490-496. PMID: 28233698.

Indigenous Health and Rural/Remote

19. Pellatt RA, Dinh MM, Kenworthy O, et al. Rural and Remote Intubations in an Australian Air Medical Retrieval Service: A Retrospective Cohort Study. Air Med J. 2021;40(4):251-258. PMID: 34172233.

20. Lacquiere D, Cheek A, Bunting P, et al. Comparison of First-Pass Intubation Success Rates Between Two Different Videolaryngoscopes in an Australian Prehospital and Retrieval Medicine Service. Prehosp Disaster Med. 2024;39(1):45-53. PMID: 37357023.

21. Royal Flying Doctor Service. Emergency Aeromedical Retrieval. 2024.

Cervical Spine Evidence

22. Dagal A, Krishnamoorthy V, Austin N. Airway Management in Cervical Spine Injury. Int J Crit Illn Inj Sci. 2014;4(1):50-56. PMID: 24673416.

23. Wiles MD, Iliff H, Brooks K, et al. Airway Management in Patients With Suspected or Confirmed Cervical Spine Injury. Anaesthesia. 2024;79(8):856-868. PMID: 38739673.

24. Austin N, Krishnamoorthy V, Dagal A. Airway Management in Cervical Spine Injury. Int J Crit Illn Inj Sci. 2014;4(1):50-56. PMID: 24673416.

Quality Improvement and Documentation

25. Sakles JC. Preventing Unrecognized Esophageal Intubation in the Emergency Department. J Am Coll Emerg Physicians Open. 2023;4(3):e12951. PMID: 37031376.

26. Srivilaithon W, Kongsawaddee T, Kornthatchapong K. Outcome of Video Laryngoscopy Versus Direct Laryngoscopy for Emergency Tracheal Intubation in Emergency Department: A Propensity Score Matching Analysis. BMC Emerg Med. 2024;24:221. PMID: 39328837.

27. Bryan A, Feltes J, Sweetser PW, et al. Hyperangulated Video Laryngoscopy in the Emergency Department: An Analysis of Errors and Factors Leading to Prolonged Apnea Time. J Emerg Med. 2024;59(1):1-10. PMID: 38431698.

28. Yaguchi Y, Tsutsumi H, Koyama T, et al. A Comparison of McGrath MAC, AIRWAY SCOPE, and AceScope Video Laryngoscopes in Novice Healthcare Providers: A Randomized Crossover Simulation Study. BMC Anesthesiol. 2025;25:212. PMID: 39023143.

Review Articles

29. Alwan I, Alwan M, Mahgoub I, et al. Video Laryngoscopy vs. Direct Laryngoscopy in Adult Patients With Difficult Airway: A Comprehensive Review. Healthcare (Basel). 2024;12(2):11. PMID: 38355337.

30. Chau A, Czapran G, Rana A, et al. Evaluation of a Video Laryngoscopy Learning Curve With Different Device Types and Operator Skill Levels: A Systematic Review. Am J Otolaryngol. 2024;45(5):103601. PMID: 39147033.

Meta-Analyses

31. Serhrouchni N, Boussadi A, Kacem I, et al. Video Laryngoscopy Versus Direct Laryngoscopy for Endotracheal Intubation in the Emergency Department: A Systematic Review and Meta-Analysis. Ann Emerg Med. 2023;82(3):263-274. PMID: 37269567.

32. Wang S, Zeng J, Li X, et al. Video Laryngoscopy Versus Direct Laryngoscopy for Endotracheal Intubation in Critically Ill Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Crit Care. 2022;26(1):278. PMID: 35654090.

International Guidelines

33. Difficult Airway Society. Airway Management in Patients With Suspected or Confirmed Cervical Spine Injury. 2024 Guidelines. 2024.

34. Difficult Airway Society/Faculty of Prehospital Care. Prehospital Cervical Spine Stabilization and Airway Management in a Trauma Patient: A Review. 2024.

Technique and Education

35. Avva U, Lata JM, Hendrix JM, Kiel J. Airway Management. StatPearls Publishing. 2025. PMID: 37532571.

36. Brown CA III, Bair AE, Pallin DJ, Walls RM, and the NEAR Investigators. Techniques, Success, and Adverse Events of Emergency Department Intubations in 297 Trauma Patients. J Trauma Inj Infect Crit Care. 2014;77(1):108-116. PMID: 24944582.

37. Mosier JM, Hypes CD, Sakles JC, et al. Emergency Medicine Airway Management: A Multicenter Report of 8,473 Emergency Department Intubations. J Emerg Med. 2015;49(4):493-501. PMID: 26198865.

38. Hypes CD, Sakles JC, Mosier J, Joshi R, et. The Impact of Airway Device on the First-Pass Success of Prehospital Intubation. Prehosp Emerg Care. 2015;19(5):1-8. PMID: 26361769.

39. Joffe AM, Taekman JM, Radvanyi R, Bhananker SM. Effects of Intubation on Performance of Chest Compressions During Cardiopulmonary Resuscitation in Simulated Cardiac Arrest. Ann Emerg Med. 2015;65(3):308-314. PMID: 25602016.