In prehospital emergency medical services, should video laryngoscopy be used as the first-line method for endotracheal intubation instead of direct laryngoscopy?

Video Laryngoscopy Should Be Used as First-Line for Prehospital Intubation

In prehospital emergency medical services, video laryngoscopy should be the preferred first-line method for endotracheal intubation over direct laryngoscopy, particularly when difficult intubation is anticipated or when the operator is trained in its use. This recommendation prioritizes first-pass success, which directly impacts morbidity and mortality by reducing complications associated with multiple intubation attempts.

Evidence-Based Rationale

The most recent and authoritative guidelines strongly support video laryngoscopy (VL) in critical care settings. The 2020 COVID-19 airway management consensus guidelines explicitly state that "laryngoscopy should be undertaken with the device most likely to achieve prompt first-pass tracheal intubation in all circumstances in that operator's hands – in most fully trained airway managers this is likely to be a videolaryngoscope" 1. This recommendation extends beyond COVID-19 to general emergency airway management principles.

First-Pass Success: The Critical Outcome

First-pass intubation success is paramount because multiple attempts are associated with significant harm, including airway trauma, bleeding, soft tissue swelling, hypoxemia, hypotension, esophageal intubation, and cardiac arrest 2, 3. The evidence demonstrates:

• VL increases first-pass success rates by 12.6-16% compared to direct laryngoscopy in prehospital settings 4, 5
• A 2025 UK HEMS study showed 92% first-pass success with VL versus 84% with direct laryngoscopy 4
• Meta-analysis of emergency intubations found VL superior for first-attempt success (RR = 1.09,95% CI [1.02,1.18]) 3
• Prehospital meta-analysis showed VL associated with higher first-pass success (RR = 1.116,95% CI 1.005-1.239) 6

ICU and Critical Care Evidence Supporting VL

The 2017 ICU intubation guidelines provide Grade 2+ recommendations that VL should be used either initially or after failure of direct laryngoscopy 7. More specifically, when difficulty is predicted (MACOCHA score ≥3), VL as first-line is preferred 7.

Key ICU data demonstrates:

• VL increased first-attempt success from 55% to 79% (C-Mac vs. Macintosh) 7
• Meta-analysis of 2,133 ICU patients showed VL increased first-attempt success (OR 2.07,95% CI 1.35-3.16) 7
• VL reduced esophageal intubation (OR 0.14,95% CI 0.02-0.81), a potentially lethal complication 7
• VL reduced Cormack-Lehane Grade III/IV views from 20% to 7% 7

Practical Implementation Algorithm

When to Use VL First-Line:

1. All intubations when VL is available and provider is trained (default approach)
2. Mandatory first-line when:
   • Predicted difficult airway (limited mouth opening, cervical immobility, obesity)
   • Critical illness with limited physiologic reserve
   • Need to maximize distance from airway (infection control)

When Direct Laryngoscopy May Be Considered:

Contraindications to VL:

• Mouth opening <2.5 cm 8
• Cervical spine fixed in flexion 8
• Upper airway tumor with stridor 8
• Rapid sequence intubation with high aspiration risk (VL may take longer initially) 8

Device Selection:

• VL with Macintosh blade (e.g., C-Mac, McGrath Mac): Use with bougie, allows direct view option 1
• VL with hyperangulated blade (e.g., GlideScope): Requires stylet 1
• Separate screen preferred to maximize operator distance from airway 1

Critical Caveats and Pitfalls

Training Requirements

Success with VL is operator-dependent 2. The 2018 British guidelines note that evidence "highlights the importance of training in success with videolaryngoscopy" 2. Providers must:

• Receive structured training on their specific VL device
• Understand that improved glottic view doesn't automatically translate to tube placement success
• Practice tube delivery techniques specific to VL (especially with hyperangulated blades)

Common Errors to Avoid

1. Screen fixation: Novice providers may focus only on the screen and lose 3D spatial awareness. A 2025 study showed that forcing initial direct visualization before VL actually increased time to intubation without improving success 9

2. Tube delivery failure: Despite excellent view, tube passage may fail. Always have a bougie or stylet ready 1

3. Trauma risk: VL with stylet can cause upper airway trauma. Be gentle during tube advancement 8

4. Time considerations: While VL generally improves success, it may not always be faster. In full-stomach patients at high aspiration risk, this matters 8

The Three-Attempt Rule

Regardless of device, limit attempts to three maximum 2, 10. After first failure:

• Ensure FONA (front-of-neck-access) equipment immediately available
• Summon senior help
• Optimize between attempts (positioning, suction, different blade, reduce cricoid pressure)
• If hypoxemia develops, ventilate via mask or supraglottic device

Nuanced Considerations

The 2018 anaesthesia guidelines show some divergence: they recommend VL as second-line after direct laryngoscopy failure when difficulty wasn't anticipated 8. However, this conflicts with more recent evidence and the 2020 consensus favoring VL first-line 1. The trend in guidelines is clearly moving toward VL as default, particularly given the unpredictability of difficult airways in emergency settings.

The prehospital environment presents unique challenges (positioning, lighting, environmental factors), but recent prehospital-specific data strongly supports VL 4, 6, 11, 5. The 2017 UK prehospital guidelines recommend routine bougie use and limit attempts to three, with VL as part of the standard approach 10.

Bottom line: Use VL first-line in EMS when available and you're trained, as it maximizes first-pass success and reduces life-threatening complications like esophageal intubation and multiple attempts.