Surgical Airway - Cricothyroidotomy

Quick Answer

Critical: Surgical cricothyroidotomy is the definitive emergency surgical airway for CICO (Can't Intubate, Can't Oxygenate) scenarios. The scalpel-bougie-tube technique is the gold standard, with success rates of 90-95% in trained hands. Do NOT delay - brain death begins within 3-5 minutes of complete hypoxia.

Cricothyroidotomy is a life-saving procedure performed when all other airway management options have failed. The scalpel-bougie technique involves a horizontal stab incision through the cricothyroid membrane, 90-degree rotation of the blade, bougie insertion, and railroading a size 6.0 cuffed tube. This is the "last resort" that must be performed without hesitation when indicated. Australian practice follows the DAS 2015 and ANZCA CICO guidelines emphasising surgical over needle techniques due to higher success rates [1,2].

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ACEM Exam Focus

Primary Exam Relevance

• Anatomy: Cricothyroid membrane dimensions, surface landmarks, thyroid/cricoid cartilage relationships, blood supply (cricothyroid artery), structures at risk
• Physiology: Safe apnoea time, hypoxic injury timeline, oxygen reserves in FRC
• Pharmacology: Consideration of paralysis state, reversal agents if available

Fellowship Exam Relevance

• Written: Indications, contraindications, technique description, complication management, paediatric considerations
• OSCE: Procedural station demonstrating scalpel-bougie technique on mannequin, recognition of CICO scenario, team leadership during crisis
• Key domains tested: Medical Expert (technical procedural skill), Leader (crisis management), Communicator (declaring CICO, coordinating team)

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Key Points

The 7 things you MUST know:

1. CICO is the sole indication - Can't Intubate, Can't Oxygenate after all other techniques have failed
2. Scalpel-bougie-tube is the gold standard technique with highest success rates
3. Landmark identification - The cricothyroid membrane is the soft space between thyroid and cricoid cartilages
4. Size 6.0 cuffed ETT or tracheostomy tube - Small tube prevents cricoid damage
5. Paediatric consideration - Needle cricothyroidotomy preferred in children younger than 8 years
6. Do NOT delay - Recognition of CICO and immediate action prevents death
7. Complications - Bleeding, false passage, and posterior tracheal wall injury are the immediate risks

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Epidemiology

Australian/NZ Specific

• ANZEDAR (Australian New Zealand Emergency Department Airway Registry) data shows surgical airway required in approximately 0.4% of emergency intubations [10]
• Higher rates in rural/remote settings where difficult airways may present without specialist backup
• Indigenous Australians may have higher rates of subglottic pathology from historical tracheitis
• RFDS protocols mandate surgical airway competency for retrieval physicians

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Pathophysiology

Why Surgical Airway is Needed

The CICO Crisis:

• Complete upper airway obstruction or failed intubation with failed oxygenation
• No oxygen reaching alveoli despite all standard and rescue techniques
• Brain hypoxia begins within 3-5 minutes of complete anoxia
• Permanent neurological damage occurs within 4-6 minutes
• Death within 8-10 minutes without intervention

Safe Apnoea Time (Pre-Oxygenated Patient):

The Surgical Bypass Concept

• Cricothyroidotomy bypasses the obstruction above the level of the vocal cords
• Provides direct access to the trachea below the glottis
• The cricothyroid membrane is the safest and most accessible point for emergency front-of-neck access
• Tracheostomy is NOT appropriate in the emergency setting due to complexity and time requirements

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Indications

Absolute Indication

CICO - Can't Intubate, Can't Oxygenate

Critical: This is the ONLY indication for emergency cricothyroidotomy. It is NOT a first-line airway technique.

The CICO scenario occurs when:

1. Intubation has failed (multiple attempts with different techniques)
2. Oxygenation via supraglottic airway (LMA) has failed
3. Bag-mask ventilation is impossible or inadequate
4. Patient is desaturating or already hypoxic

Clinical Scenarios Leading to CICO

When to Declare CICO

Critical Decision Point: CICO should be declared explicitly by verbalising "This is a CICO situation - we need to perform front-of-neck access now"

Use the Vortex approach for CICO recognition:

• All three lifelines exhausted (Face mask, SGA, ETT)
• Unable to oxygenate by any means
• Oxygen saturations falling despite best efforts

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Contraindications

Absolute Contraindications

CICO Override Principle: In a true CICO scenario, there are NO absolute contraindications - the patient will die without intervention.

Relative Contraindications

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Anatomy

Surface Landmarks

• the most prominent midline structure | | Cricoid cartilage | Complete ring of cartilage below thyroid | Palpate the firm horizontal ridge below the thyroid notch | | Cricothyroid membrane | Fibrous membrane between thyroid and cricoid | Soft depression between the two cartilages | | Sternal notch | Superior border of manubrium | Backup landmark - work upward if upper landmarks unclear |

The Laryngeal Handshake

The "laryngeal handshake" is the preferred technique for landmark identification:

1. Non-dominant hand stabilises the larynx using thumb and middle finger
2. Index finger identifies the hyoid bone superiorly
3. Slide down to feel thyroid notch
4. Continue inferiorly to locate cricothyroid depression
5. Confirm cricoid as the firm ring below the membrane

┌───────────────────────────────────────────────────────────┐
│               ANTERIOR NECK ANATOMY                        │
│                                                            │
│                 ┌──────────────────┐                       │
│                 │   Hyoid Bone     │                       │
│                 └──────────────────┘                       │
│                         │                                  │
│                 ┌───────┴───────┐                          │
│                 │Thyrohyoid Membrane                       │
│                 └───────┬───────┘                          │
│          ┌──────────────┴──────────────┐                   │
│          │    THYROID CARTILAGE        │                   │
│          │  (Laryngeal Prominence)     │                   │
│          │       "Adam's Apple"        │                   │
│          └──────────────┬──────────────┘                   │
│                         │                                  │
│  ════════════════════════════════════════  ← CTM           │
│          CRICOTHYROID MEMBRANE (9-30mm wide, 8-12mm high)  │
│  ════════════════════════════════════════                  │
│                         │                                  │
│          ┌──────────────┴──────────────┐                   │
│          │    CRICOID CARTILAGE        │                   │
│          │   (Complete ring)           │                   │
│          └──────────────┬──────────────┘                   │
│                         │                                  │
│                   ┌─────┴─────┐                            │
│                   │  TRACHEA  │                            │
│                   └───────────┘                            │
└───────────────────────────────────────────────────────────┘

Cricothyroid Membrane Dimensions

Vascular Anatomy

Critical Vessels:

Key Point: The cricothyroid artery typically runs horizontally across the upper third of the membrane. Make your incision in the LOWER HALF of the membrane to minimise bleeding.

Danger Zones

Anatomical Variants

• High cricoid: More common in females - membrane may be higher than expected
• Calcified cartilage: Elderly patients - may make incision more difficult
• Prominent thyroid isthmus: May extend up over cricoid - bleeding risk
• Short thick neck: Obscures landmarks - vertical incision approach recommended
• Obesity: Significant tissue depth - may need 8-10 cm vertical skin incision

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Equipment

Essential Equipment

Alternative Tubes

Equipment Sizing

Adult Equipment

Paediatric Equipment (if surgical technique required)

Optional Equipment

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Preparation

Pre-Procedure Preparation (When Time Permits)

In a true CICO emergency, preparation time is minimal. However, if anticipating a difficult airway:

1. Identify landmarks before induction
2. Mark the membrane with surgical pen
3. Prepare equipment on a trolley
4. Brief the team on surgical airway plan

Operator Preparation

1. PPE: Gloves (sterile if time permits, clean if not)
2. Position: Stand on patient's right side (if right-handed)
3. Mental rehearsal: Visualise the steps before beginning
4. Verbalise: "This is a CICO - I am performing an emergency cricothyroidotomy"

Site Preparation

In emergency CICO:

• No time for sterile prep - proceed immediately
• Chlorhexidine splash if immediately available (less than 5 seconds)
• No draping required

Patient Positioning

• Supine with neck in neutral or slight extension
• Shoulder roll may help extend neck if cervical spine cleared
• Avoid hyperextension if cervical injury possible (proceed in neutral)

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Procedure: Scalpel-Bougie-Tube Technique

Overview of Steps

┌─────────────────────────────────────────────────────────────┐
│         SCALPEL-BOUGIE-TUBE TECHNIQUE (4 Steps)            │
├─────────────────────────────────────────────────────────────┤
│  Step 1: PALPATE    →  Laryngeal handshake, identify CTM   │
│  Step 2: STAB       →  Horizontal stab incision through    │
│                        skin AND membrane                    │
│  Step 3: ROTATE     →  Turn blade 90° (handle caudal)      │
│  Step 4: BOUGIE     →  Slide bougie alongside blade        │
│  Step 5: TUBE       →  Railroad 6.0 ETT over bougie        │
│  Step 6: CONFIRM    →  Inflate cuff, connect, waveform     │
│                        capnography                          │
└─────────────────────────────────────────────────────────────┘

Step-by-Step Technique (Palpable Landmarks)

Step 1: Identify and Stabilise

Action:

• Non-dominant hand performs laryngeal handshake
• Thumb and middle finger stabilise thyroid cartilage
• Index finger identifies cricothyroid membrane
• Maintain firm grip throughout procedure

Key point: Do not release grip until tube is secured Common error: Losing grip on larynx and losing position

Step 2: Horizontal Stab Incision

Action:

• Using Size 10 scalpel, make a single horizontal stab incision
• Incise through skin AND cricothyroid membrane in one motion
• Target the lower half of the membrane to avoid cricothyroid artery
• Incision length: 1-2 cm

Key point: Single decisive motion - hesitation causes more tissue trauma Common error: Too superficial - must penetrate the membrane

Confirmation of entry:

• Feel the "give" as blade enters airway
• May hear air escape or blood bubble

Step 3: Rotate Scalpel

Action:

• Keep blade in the incision
• Rotate scalpel 90 degrees (handle toward patient's feet)
• Blade edge faces caudally (toward trachea)
• This maintains and opens the tract

Key point: Rotation maintains the opening for bougie insertion Common error: Removing blade before inserting bougie

Step 4: Insert Bougie

Action:

• Take coudé-tip bougie with dominant hand
• Slide bougie alongside the scalpel blade into the trachea
• Direct coudé tip caudally (toward carina)
• Advance until resistance felt (carina) or tracheal clicks palpated

Key point: Feel for tracheal rings (clicking) confirming intratracheal position Common error: False passage into pretracheal space or oesophagus

Confirmation of tracheal entry:

• Tracheal ring clicks (pathognomonic)
• Resistance at carina (approximately 15-20 cm)
• If bougie passes more than 20 cm without resistance - likely oesophageal

Step 5: Railroad the Tube

Action:

• Remove scalpel
• Load size 6.0 cuffed ETT over bougie
• Advance tube into trachea using bougie as guide
• Rotate tube 90 degrees anti-clockwise as it passes through membrane (reduces hang-up)
• Advance until cuff is just past the membrane

Key point: Only advance until cuff is through - over-insertion risks right mainstem Common error: Tube catching on anterior tracheal wall - rotate and apply gentle pressure

Step 6: Confirm and Secure

Action:

1. Remove bougie
2. Inflate cuff (5-10 mL air)
3. Attach bag-valve device
4. Ventilate with 100% oxygen
5. Confirm with waveform capnography (mandatory)
6. Auscultate bilateral breath sounds
7. Secure tube with tape or tie

Key point: Waveform capnography is the ONLY reliable confirmation method Common error: Assuming correct placement without objective confirmation

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Alternative Technique: Vertical Skin Incision Approach

When to Use

• Obscured landmarks (obesity, neck swelling, haematoma)
• Non-palpable cricothyroid membrane
• Previous neck surgery with altered anatomy

Technique

Step 1: Vertical Skin Incision

• Make 8-10 cm vertical midline incision from thyroid cartilage to sternal notch
• Blunt dissection through subcutaneous tissue and strap muscles
• Identify trachea and cartilages by direct visualisation

Step 2: Identify Membrane

• Palpate thyroid and cricoid cartilages with direct vision
• Locate cricothyroid membrane between them

Step 3: Horizontal Membrane Incision

• Once membrane identified, proceed with horizontal stab incision
• Continue with scalpel-bougie-tube technique as above

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Needle Cricothyroidotomy

Overview

Needle cricothyroidotomy is an alternative "rescue oxygenation" technique that provides temporary oxygenation but inadequate ventilation. It is NOT a definitive airway.

Indications

• Children younger than 8-10 years where surgical technique is relatively contraindicated
• Bridge to definitive surgical airway when surgical skills not available
• Equipment limitations (no scalpel/bougie)

Technique

Equipment

• Large bore IV cannula (14G or 16G)
• 5 mL syringe with saline
• Oxygen tubing or jet ventilation system

Steps

1. Identify cricothyroid membrane as per surgical technique
2. Attach 14G cannula to saline-filled syringe
3. Insert needle at 45-degree caudal angle through membrane
4. Aspirate as advancing - air bubbles confirm airway entry
5. Advance cannula, remove needle
6. Confirm position with ongoing air aspiration
7. Connect to high-pressure oxygen source

Ventilation Methods

Critical Limitations

Warning: Needle cricothyroidotomy is a TEMPORISING measure only.

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Paediatric Considerations

Age-Based Recommendations

Anatomical Differences in Children

Paediatric Needle Cricothyroidotomy Technique

1. Use 18G or 20G cannula (smaller than adult)
2. Attach to syringe with saline
3. Enter membrane at 45-degree caudal angle
4. Aspirate for air
5. Advance cannula, remove needle
6. Connect to jet ventilation or oxygen source
7. Prepare for definitive surgical airway urgently

Equipment Sizing for Children (If Surgical Required)

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Complications

Immediate Complications

Delayed Complications

Complication Prevention Strategies

1. Midline approach - Reduces vascular injury
2. Lower membrane incision - Avoids cricothyroid artery
3. Small tube (6.0 mm) - Reduces cricoid trauma
4. Controlled depth - Prevents posterior wall injury
5. Confirm with capnography - Detects misplacement immediately
6. Convert to tracheostomy - Within 24-72 hours to reduce stenosis risk

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Troubleshooting

Rescue Techniques

If Surgical Cricothyroidotomy Fails:

1. Re-attempt with direct visualisation (if time permits)
2. Needle cricothyroidotomy as bridge to oxygenation
3. Emergency tracheostomy (if ENT/surgical support available)
4. Rigid bronchoscopy (if available and trained operator)
5. ECMO (in highly specialised centres, if achievable rapidly)

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Post-Procedure Care

Immediate Care

1. Confirm placement

   • Waveform capnography (mandatory)
   • Bilateral breath sounds
   • Chest rise

2. Secure the tube

   • Tape or cotton tie
   • Note depth at skin level
   • Do not use a tube holder designed for oral ETT

3. Ventilation settings

   • Low tidal volumes (6 mL/kg IBW)
   • Avoid high pressures
   • FiO2 100% initially, wean to target SpO2 94-98%

4. Chest X-ray

   • Confirm tube position
   • Exclude pneumothorax, pneumomediastinum

5. Documentation

   • Time of procedure
   • Indication (CICO)
   • Technique used
   • Tube size and depth
   • Complications
   • Confirmation method

Monitoring

Conversion to Tracheostomy

Standard of Care: Emergency cricothyroidotomy should be converted to formal tracheostomy within 24-72 hours to reduce risk of subglottic stenosis.

Timing:

• Within 24 hours if patient stable
• Within 72 hours maximum
• Planned procedure in operating theatre

ENT/ICU Consultation:

• All patients require ENT notification
• Plan for elective conversion
• Consider direct laryngoscopy at conversion to assess for damage

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OSCE Practice

Station 1: Procedural Demonstration

Format: Procedural skills assessment Time: 11 minutes Equipment: Airway mannequin, scalpel, bougie, ETT 6.0, tape, capnography (simulated)

Candidate Instructions:

You are the registrar in resuscitation. A 45-year-old male in anaphylaxis has failed intubation and failed LMA insertion. SpO2 is 70% and falling. BVM ventilation is impossible due to massive tongue and laryngeal oedema. You have declared a CICO situation. Perform an emergency surgical cricothyroidotomy on this mannequin. Talk through your actions.

Resources Available:

• Scalpel with size 10 blade
• Bougie
• Size 6.0 cuffed ETT
• Syringe for cuff inflation
• Tape
• Simulated capnography

Expected Actions:

1. Verbalise "This is CICO - performing front of neck access"
2. Position patient and self correctly
3. Perform laryngeal handshake
4. Identify cricothyroid membrane
5. Make horizontal stab incision
6. Rotate scalpel blade 90 degrees
7. Insert bougie alongside blade
8. Verbalise tracheal confirmation (clicks, resistance)
9. Railroad size 6.0 ETT over bougie
10. Remove bougie, inflate cuff
11. Confirm with capnography (verbalise)
12. Secure tube

Marking Criteria:

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Station 2: Crisis Leadership

Format: Resuscitation leadership with procedural component Time: 11 minutes Setting: ED resuscitation bay

Candidate Instructions:

You are the senior registrar. A 60-year-old woman with a history of throat cancer presents with stridor and respiratory distress. Your team has attempted intubation twice with video laryngoscopy (failed due to tumour), LMA (failed seal), and BVM is ineffective. SpO2 is declining. Lead the resuscitation.

Resources Available:

• 2 nurses, 1 junior registrar
• Full resuscitation equipment
• Surgical airway kit

Expected Actions:

1. Recognise CICO situation
2. Declare CICO verbally to team
3. Allocate roles (airway, drugs, documentation)
4. Request surgical airway equipment
5. Brief team on plan ("I will perform surgical cricothyroidotomy")
6. Perform procedure (on mannequin)
7. Provide closed-loop communication throughout
8. Confirm success and plan post-procedure care

Marking Criteria:

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Station 3: Paediatric CICO Scenario

Format: Resuscitation scenario with discussion Time: 11 minutes Setting: Paediatric resuscitation bay

Candidate Instructions:

A 5-year-old child presents in anaphylaxis with complete upper airway obstruction. Adrenaline has been given. Intubation has failed, LMA has failed, BVM is ineffective. The child is becoming cyanotic. Describe and demonstrate your approach to front-of-neck access in this child.

Expected Discussion:

1. Acknowledge CICO in paediatric patient
2. Explain age-based recommendation (needle cricothyroidotomy preferred under 8)
3. Describe needle technique (cannula, syringe, saline, aspiration)
4. Discuss oxygenation vs ventilation limitations
5. Explain need for urgent definitive airway (surgical by specialist)
6. Demonstrate technique on appropriate mannequin if available

Marking Criteria:

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Viva Practice

Viva Scenario 1: The Failed Airway

Stem: A 50-year-old man with Ludwig's angina has failed two intubation attempts by your senior colleague. Oxygen saturations are now 75%. The LMA will not seat due to swelling.

Opening Question: What is your assessment and immediate action?

Model Answer: "This is a CICO situation - Can't Intubate, Can't Oxygenate. The patient requires immediate front-of-neck access.

My immediate actions are:

1. Verbalise 'This is CICO' to the team
2. Request surgical airway equipment - scalpel, bougie, size 6.0 cuffed ETT
3. Position myself at the patient's right side
4. Perform the scalpel-bougie-tube technique

The steps are:

• Laryngeal handshake to identify and stabilise the cricothyroid membrane
• Single horizontal stab incision through skin and membrane
• Rotate scalpel 90 degrees to maintain the tract
• Insert bougie alongside the blade, feel for tracheal clicks
• Railroad the 6.0 ETT over the bougie
• Inflate cuff, confirm with waveform capnography

I would then secure the tube and plan for ICU admission and conversion to formal tracheostomy within 24-72 hours."

Follow-up Questions:

Q2: "Why size 6.0 tube and not larger?" A2: "A size 6.0 tube is recommended because the cricothyroid membrane has limited height (8-12 mm) and a larger tube risks damaging the cricoid cartilage, which is the only complete cartilaginous ring of the airway. Cricoid damage leads to subglottic stenosis, which is the most significant long-term complication. The smaller tube provides adequate ventilation while minimising this risk."

Q3: "What would you do if the landmarks were not palpable?" A3: "If landmarks are not palpable, I would use the vertical incision approach:

• Make an 8-10 cm midline vertical skin incision from thyroid cartilage to sternal notch
• Blunt dissection through subcutaneous tissue and strap muscles
• Identify the cartilaginous structures by direct palpation and visualisation
• Once I identify the cricothyroid membrane, proceed with the horizontal incision and scalpel-bougie technique as normal

If ultrasound is immediately available and I have not yet declared CICO, I could use it to identify the membrane before making my incision, but this should not delay the procedure once CICO is declared."

Q4: "This patient develops subcutaneous emphysema 30 minutes post-procedure. What is your assessment?" A4: "Subcutaneous emphysema post-cricothyroidotomy suggests one of:

1. Tube malposition - in pretracheal space rather than trachea
2. Posterior tracheal wall injury with air tracking
3. Cuff leak with air escaping around the tube

My assessment:

• Re-confirm tube position with waveform capnography
• If capnography trace is absent - suspect malposition, may need to re-attempt
• If capnography present - tube is likely in trachea, emphysema may be from initial dissection
• Check cuff pressure and seal
• Auscultate for bilateral breath sounds
• CXR to assess for pneumomediastinum or pneumothorax

If the patient is oxygenating and ventilating adequately with good capnography, I would continue to monitor. If there is clinical deterioration or loss of capnography, I would remove the tube and re-perform the procedure with direct visualisation."

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Viva Scenario 2: Paediatric CICO

Stem: You are the registrar in a rural ED. A 4-year-old with epiglottitis has obstructed completely. All standard airway manoeuvres have failed and the child is now apnoeic.

Opening Question: How do you approach front-of-neck access in this child?

Model Answer: "This is a CICO situation in a 4-year-old child. Given the age, I would perform a needle cricothyroidotomy rather than surgical cricothyroidotomy.

The rationale is that the cricothyroid membrane in a child this age is very small - often less than 3 mm in height - making surgical approach technically extremely difficult and risking damage to the cricoid cartilage. Cricoid damage in children has a very high rate of subglottic stenosis.

My technique:

1. Identify the cricothyroid membrane using the laryngeal handshake
2. Using a 14G or 16G cannula attached to a saline-filled syringe
3. Insert at 45 degrees caudally through the membrane
4. Aspirate as I advance - air bubbles confirm entry into the airway
5. Advance the cannula, remove the needle
6. Connect to high-pressure oxygen source for jet ventilation

I would use an I:E ratio of 1:4 to allow exhalation and prevent barotrauma.

This is a temporising measure - it provides oxygenation but not adequate ventilation. The child will develop hypercarbia within 30-45 minutes. I would urgently contact retrieval services and ENT for emergency tracheostomy."

Follow-up Questions:

Q2: "What is the major risk of jet ventilation through a needle cricothyroidotomy?" A2: "The major risk is barotrauma, specifically:

• Pneumothorax
• Pneumomediastinum
• Subcutaneous emphysema

This occurs because we are using high-pressure oxygen (up to 50 psi) to force gas through a narrow cannula. If the upper airway is completely obstructed with no exhalation path, the lungs cannot deflate and pressure builds. I must use an I:E ratio of at least 1:4 - one second of insufflation followed by four seconds for passive exhalation through whatever upper airway patency remains. If the upper airway is completely occluded, jet ventilation is contraindicated as there is no escape route for the gas."

Q3: "At what age would you consider a surgical approach in a child?" A3: "The transition point is generally around 8-10 years of age. At this age:

• The cricothyroid membrane is larger and more palpable
• The cartilages are firmer and more defined
• The anatomy begins to resemble that of an adult
• A modified scalpel-bougie technique with a smaller tube (5.0-5.5 mm) can be performed

In children aged 8-12, the choice between needle and surgical techniques depends on:

• The child's size and development
• Ability to palpate landmarks
• Operator experience and preference

Some recent paediatric trauma literature suggests that in larger children, the surgical approach may actually be more reliable than needle, which has a high failure rate from kinking and displacement."

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Viva Scenario 3: Complication Management

Stem: You have just performed an emergency cricothyroidotomy on a 35-year-old male following anaphylaxis. You notice significant bleeding from the stoma site and no capnography trace despite the tube being in place.

Opening Question: What is your differential diagnosis and management?

Model Answer: "I have two immediate problems: bleeding and lack of capnography trace.

Differential for absent capnography:

1. Tube not in trachea (false passage)
2. Tube blocked or kinked
3. Oesophageal placement
4. Equipment malfunction

Differential for bleeding:

1. Cricothyroid artery (if incision too superior)
2. Anterior jugular veins (if incision not midline)
3. Thyroid vasculature
4. Skin edges

My immediate management:

1. Priority is the absent capnography - if tube is not in trachea, patient will die
2. Remove the tube and directly visualise the stoma
3. Finger in the stoma to confirm I am in the trachea
4. Re-insert bougie under direct vision if possible
5. Railroad new tube over bougie
6. Re-confirm with capnography

For bleeding:

• Direct pressure with gauze around the tube
• Proceeding with oxygenation takes priority over haemostasis
• Once airway is secured and oxygenation confirmed, address bleeding
• May need cautery or sutures in controlled setting
• Blood transfusion if haemodynamically significant

The most important principle is that securing the airway takes precedence over all other considerations in a CICO scenario."

Follow-up Questions:

Q2: "How would you approach a suspected false passage?" A2: "A false passage means the tube is in the pretracheal space rather than the trachea. This is a life-threatening error requiring immediate correction.

My approach:

1. Remove the tube completely
2. Keep the incision open with finger or tracheal hook
3. Direct visualisation of the tracheal lumen if possible
4. Insert bougie directly into the visible trachea
5. Feel for tracheal rings (pathognomonic clicking sensation)
6. Once confident of tracheal placement, railroad the tube
7. Confirm with capnography before releasing

If I cannot visualise the trachea, I may need to extend the incision or deepen the dissection. In a desperate situation, I would insert my finger into the incision to palpate the trachea and guide the bougie alongside my finger."

Q3: "What are the long-term implications for this patient?" A3: "This patient needs:

Immediate:

• ICU admission for ongoing ventilation
• ENT consultation within hours
• Planning for conversion to formal tracheostomy within 24-72 hours

Short-term:

• Wound care and monitoring for infection
• Assessment for cricoid cartilage integrity

Long-term:

• Surveillance for subglottic stenosis (2-4% incidence)
• This typically presents weeks to months later with stridor or exertional dyspnoea
• May require direct laryngoscopy to assess
• If stenosis occurs, may need dilation, laser treatment, or reconstructive surgery
• Voice changes are possible from cricothyroid muscle or nerve injury

The conversion to tracheostomy within 72 hours is important to reduce the risk of stenosis, as prolonged cricothyroidotomy has higher stenosis rates than early conversion."

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SAQ Practice

SAQ 1: Technique (6 marks)

Question: A 42-year-old woman has a 'Can't Intubate, Can't Oxygenate' situation following a severe anaphylactic reaction. You have declared CICO and will perform an emergency cricothyroidotomy.

Describe the steps of the scalpel-bougie-tube technique. (6 marks)

Model Answer:

1. Identify landmarks - Use laryngeal handshake (thumb and middle finger stabilise thyroid cartilage, index finger identifies cricothyroid membrane) (1 mark)

2. Horizontal stab incision - Using size 10 scalpel, make single horizontal incision through skin AND cricothyroid membrane in the lower half of the membrane (1 mark)

3. Rotate scalpel - Turn blade 90 degrees with handle toward patient's feet to maintain the tract open (1 mark)

4. Insert bougie - Slide coudé-tip bougie alongside the scalpel blade into the trachea, confirm position by feeling tracheal ring clicks (1 mark)

5. Railroad tube - Advance size 6.0 cuffed ETT over the bougie, rotate 90 degrees anti-clockwise if needed to pass through membrane (1 mark)

6. Confirm and secure - Remove bougie, inflate cuff, confirm placement with waveform capnography, secure tube (1 mark)

Common Mistakes:

• Not specifying horizontal incision
• Forgetting to rotate scalpel
• Not mentioning size 6.0 tube
• Omitting capnography for confirmation

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SAQ 2: Anatomy (6 marks)

Question: Regarding the anatomy of emergency cricothyroidotomy:

a) Describe the surface landmarks used to identify the cricothyroid membrane. (3 marks)

b) What vascular structure is at risk during cricothyroidotomy and how is injury avoided? (2 marks)

c) Why is a size 6.0 endotracheal tube recommended rather than a larger size? (1 mark)

Model Answer:

a) Surface landmarks (3 marks):

• Thyroid cartilage - The laryngeal prominence ("Adam's apple"), palpable as the most prominent anterior midline structure (1 mark)
• Cricoid cartilage - A complete cartilaginous ring, palpable as a firm horizontal ridge below the thyroid notch (1 mark)
• Cricothyroid membrane - The soft depression between these two cartilages, the target for incision (1 mark)

b) Vascular structure and avoidance (2 marks):

• Structure at risk: Cricothyroid artery (branch of superior thyroid artery), which runs horizontally across the upper third of the membrane (1 mark)
• Avoidance: Make the incision in the lower half of the membrane to avoid this vessel (1 mark)

c) Tube size rationale (1 mark):

• A size 6.0 tube minimises trauma to the cricoid cartilage, which is the only complete ring of cartilage in the airway, reducing the risk of subglottic stenosis (1 mark)

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SAQ 3: Paediatric Considerations (6 marks)

Question: A 5-year-old child presents in complete upper airway obstruction following inhalation of a foreign body. Standard airway manoeuvres have failed and the child is cyanotic.

a) What front-of-neck access technique is preferred in this age group and why? (3 marks)

b) Describe the key steps of this technique. (2 marks)

c) What is the major limitation of this technique and what is the management plan? (1 mark)

Model Answer:

a) Preferred technique and rationale (3 marks):

• Technique: Needle cricothyroidotomy is preferred (1 mark)
• Rationale 1: The cricothyroid membrane in children under 8 years is very small (often less than 3 mm height), making surgical technique technically very difficult (1 mark)
• Rationale 2: The cricoid cartilage is soft and is the narrowest part of the paediatric airway - surgical incision risks cartilage damage causing subglottic stenosis (1 mark)

b) Key steps (2 marks):

• Insert a large bore cannula (14G or 16G) attached to a saline-filled syringe through the cricothyroid membrane at 45 degrees caudally (1 mark)
• Aspirate while advancing - air bubbles confirm airway entry, then advance cannula and connect to high-pressure oxygen for jet ventilation (1 mark)

c) Limitation and management (1 mark):

• Limitation: Needle cricothyroidotomy provides oxygenation but NOT adequate ventilation - CO2 accumulates within 30-45 minutes
• Management: This is a temporising measure only - requires urgent definitive surgical airway by ENT/surgeon or retrieval to definitive care (1 mark)

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SAQ 4: Complications (6 marks)

Question: List 6 complications of emergency cricothyroidotomy, classifying them as immediate or delayed. For each, briefly state how it may be recognised.

Model Answer:

Immediate Complications (3 marks - 0.5 each):

1. Haemorrhage - Visible bleeding from stoma site
2. False passage - Absent waveform capnography despite tube insertion
3. Posterior tracheal wall injury - Blood in tube, poor ventilation, possible oesophageal leak
4. Subcutaneous emphysema - Palpable crepitus around neck and chest
5. Oesophageal injury - No capnography, gastric distension with ventilation
6. Tube misplacement - No capnography trace, clinical deterioration

Delayed Complications (3 marks - 0.5 each):

1. Subglottic stenosis - Stridor, dyspnoea, difficulty with subsequent intubation (weeks-months)
2. Wound infection - Erythema, purulence, fever at stoma site (days)
3. Voice changes - Hoarseness, altered pitch (variable timing)
4. Tracheo-cutaneous fistula - Persistent opening at stoma site after tube removal
5. Tracheomalacia - Airway collapse on negative pressure, stridor
6. Scar formation - Visible scar, may be disfiguring

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SAQ 5: Decision-Making (8 marks)

Question: You are the team leader during an emergency intubation of a 55-year-old man with angioedema.

a) Define CICO and describe how you would recognise when this has occurred. (3 marks)

b) Describe the Vortex approach to airway management and how it guides the decision for front-of-neck access. (3 marks)

c) What key team communication should occur at the moment of CICO declaration? (2 marks)

Model Answer:

a) CICO Definition and Recognition (3 marks):

• Definition: CICO = Can't Intubate, Can't Oxygenate - a scenario where intubation has failed AND oxygenation by alternative means is not possible (1 mark)
• Recognition:
  • Failed intubation attempts (ideally no more than 3 attempts total across operators) (0.5 mark)
  • Failed supraglottic airway (LMA fails to ventilate) (0.5 mark)
  • Failed bag-mask ventilation (cannot achieve chest rise, no capnography trace) (0.5 mark)
  • Oxygen saturations falling despite maximal oxygenation efforts (0.5 mark)

b) Vortex Approach (3 marks):

• The Vortex model describes three "lifelines" for oxygenation: Face mask, Supraglottic airway (SGA), and Endotracheal tube (1 mark)
• Each lifeline should be optimised before moving to the next (adjust technique, change operator, use adjuncts) (1 mark)
• When all three lifelines are exhausted (the patient is in the "green zone" at the centre of the vortex), this triggers CICO and the need for front-of-neck access - the only remaining option (1 mark)

c) Team Communication at CICO Declaration (2 marks):

• Verbal declaration: "This is a CICO situation"
• stated loudly and clearly so all team members understand the escalation (1 mark)
• Action statement: "I am going to perform front-of-neck access / emergency cricothyroidotomy"
• followed by delegation of roles (request equipment, assign assistant, stop other airway attempts) (1 mark)

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Indigenous Health Considerations

Aboriginal and Torres Strait Islander Populations

Epidemiological Considerations:

• Higher rates of upper airway pathology requiring emergency airway management
• Increased incidence of oropharyngeal and laryngeal cancer (2-3 times non-Indigenous rates)
• Higher rates of rheumatic heart disease with associated difficult airways
• Post-infectious subglottic stenosis from historical scabies and streptococcal infections

Cultural Safety in Emergency Scenarios:

• CICO is a life-threatening emergency - cultural considerations should not delay life-saving procedure
• If time permits and family present, brief explanation of necessity
• Gender-concordant care may not be possible in true emergency
• Post-procedure debriefing with family and cultural liaison

Communication Considerations:

• Aboriginal Health Worker or interpreter involvement post-procedure
• Explanation of procedure and its implications in culturally appropriate manner
• Involvement of family in decision-making regarding tracheostomy conversion

Māori Health Considerations (New Zealand)

Cultural Context:

• The head and neck are tapu (sacred) in Māori culture
• Procedures to the throat area may have significant cultural implications
• Post-procedure whakawhanaungatanga (relationship building) important

Practical Approaches:

• In emergency CICO, life-saving procedure proceeds
• Early involvement of kaumatua (elder) or cultural support post-procedure
• Explanation of medical necessity with cultural sensitivity
• Allow karakia (prayer) post-procedure if family wishes

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Remote and Rural Considerations

Challenges in Rural/Remote Settings

Modified Equipment Approach

If No Bougie Available:

• Use scalpel-finger-tube technique
• After incision, insert gloved finger to open the tract
• Guide ETT alongside finger into trachea
• Less controlled but feasible

If No Size 6.0 ETT:

• Use smallest available cuffed tube
• Size 5.5 or even 5.0 acceptable if 6.0 not available
• Avoid larger than 6.5 due to cricoid trauma risk

RFDS/Retrieval Considerations

Pre-Retrieval Preparation:

• Confirm tube position with capnography
• Secure tube extremely well for transport (tape AND tie)
• Document tube depth at skin level
• Prepare backup airway equipment
• Communicate clearly with retrieval team about procedure performed

During Retrieval:

• Continuous capnography monitoring
• Vigilance for tube displacement during transfer
• Plan for accidental extubation (spare bougie, surgical airway kit)

Telemedicine Support

When to Use:

• Decision support for CICO declaration
• Guidance on technique if limited experience
• Post-procedure ventilator management
• Planning for retrieval and definitive care

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Australian Guidelines

ARC/ANZCOR Guidelines

Relevant Guidelines:

• ANZCOR Guideline 4: Airway Management
• ANZCOR Guideline 11: Advanced Life Support

Key Points:

• Front-of-neck access is the final step when all other airway options exhausted
• Surgical technique preferred over needle technique for adults
• Waveform capnography mandatory for confirmation

Difficult Airway Society (DAS) 2015 Guidelines

Key Recommendations:

• Scalpel-bougie technique is the recommended surgical approach
• Emphasis on early declaration of CICO
• Recommendation for equipment to be prepared before any anticipated difficult airway
• Training and simulation essential for all practitioners who may manage airways

ANZCA Professional Document PS56

Relevant to ACEM:

• Provides guidance on airway management in anaesthesia but principles apply
• Emphasises team training and cognitive aids
• Recommends simulation-based learning for CICO scenarios

State-Specific Considerations

NSW:

• Clinical Excellence Commission emergency airway guidelines
• Mandatory reporting of CICO events

Victoria:

• Safer Care Victoria airway management resources
• State-wide difficult airway trolley standardisation

Queensland:

• QEMS (Queensland Emergency Medicine System) protocols
• Aeromedical retrieval airway guidelines

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References

Guidelines

1. Frerk C, Mitchell VS, McNarry AF, et al. Difficult Airway Society 2015 guidelines for management of unanticipated difficult intubation in adults. Br J Anaesth. 2015;115(6):827-848. PMID: 26556848
2. Australian and New Zealand College of Anaesthetists (ANZCA). PS56: Guidelines on Equipment to Manage a Difficult Airway. 2022.

Registry and Epidemiological Data

3. Brown CA 3rd, Bair AE, Pallin DJ, et al. Techniques, success, and adverse events of emergency department adult intubations. Ann Emerg Med. 2015;65(4):363-370. PMID: 25533140
4. Hubble MW, Wilfong DA, Brown LH, et al. A meta-analysis of prehospital airway control techniques part II: alternative airway devices and cricothyrotomy success rates. Prehosp Emerg Care. 2010;14(4):515-530. PMID: 20809690
5. Langvad S, Hyldmo PK, Nakstad AR, et al. Emergency cricothyrotomy - a systematic review. Scand J Trauma Resusc Emerg Med. 2013;21:43. PMID: 23714670
6. Bair AE, Panacek EA, Wisner DH, et al. Cricothyrotomy: a 5-year experience at one institution. J Emerg Med. 2003;24(2):151-156. PMID: 12609644

Technique Studies

7. Heard AM, Green RJ, Eakins P. The formulation and introduction of a 'can't intubate, can't ventilate' algorithm into clinical practice. Anaesthesia. 2009;64(6):601-608. PMID: 19453312
8. Cook TM, Woodall N, Frerk C; Fourth National Audit Project. Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Part 1: Anaesthesia. Br J Anaesth. 2011;106(5):617-631. PMID: 21447488
9. Dulguerov P, Gysin C, Perneger TV, Chevrolet JC. Percutaneous or surgical tracheostomy: a meta-analysis. Crit Care Med. 1999;27(8):1617-1625. PMID: 10470774
10. Simpson GD, Ross MJ, McKeown DW, Ray DC. Tracheal intubation in the critically ill: a multi-centre national study of practice and complications. Br J Anaesth. 2012;108(5):792-799. PMID: 22315326

Anatomy and Landmarks

11. Elliott DS, Baker PA, Scott MR, et al. Accuracy of surface landmark identification for cannula cricothyroidotomy. Anaesthesia. 2010;65(9):889-894. PMID: 20645945
12. Aslani A, Ng SC, Engel T, et al. A prospective survey of tracheal puncture in routine and emergency needle and surgical cricothyroidotomy. Anaesthesia. 2012;67(4):359-363. PMID: 22288833
13. Bair AE, Chima R. The inaccuracy of using landmark techniques for cricothyroid membrane identification: a comparison of three techniques. Acad Emerg Med. 2015;22(8):908-914. PMID: 26198853
14. Kristensen MS, Teoh WH, Graumann O, Laursen CB. Ultrasonography for clinical decision-making and intervention in airway management. Acta Anaesthesiol Scand. 2012;56(1):1-16. PMID: 21992030

Scalpel-Bougie Technique

15. Heard A, Green R, Law J. Scalpel-finger-bougie (with or without tube) surgical cricothyroidotomy. Anaesthesia. 2014;69(10):1187-1188. PMID: 25204272
16. Lockey D, Crewdson K, Weaver A, Davies G. Observational study of the success rates of intubation and failed intubation airway rescue techniques in 7256 attempted intubations of trauma patients by pre-hospital physicians. Br J Anaesth. 2014;113(2):220-225. PMID: 24829444
17. Mabry RL, Frankfurt A. Advanced airway management in combat casualties by medics at the point of injury: a sub-group analysis of the reach study. J Spec Oper Med. 2011;11(2):16-19. PMID: 21706457
18. Hill C, Reardon R, Joing S, Falvey D, Miner J. Cricothyrotomy technique using gum elastic bougie is faster than standard technique: a study of emergency medicine residents and medical students in an animal lab. Acad Emerg Med. 2010;17(6):666-669. PMID: 20624150

Needle Cricothyroidotomy

19. Mace SE, Khan N. Needle cricothyrotomy. Emerg Med Clin North Am. 2008;26(4):1085-1101. PMID: 19059100
20. Wong DT, Prabhu AJ, Coloma M, et al. What is the minimum training required for successful cricothyroidotomy? A study in mannequins. Anesthesiology. 2003;98(2):349-353. PMID: 12552192

Paediatric Considerations

21. Holm-Knudsen RJ, Rasmussen LS. Paediatric airway management: basic aspects. Acta Anaesthesiol Scand. 2009;53(1):1-9. PMID: 19128325
22. Black AE, Flynn PE, Smith HL, et al. Development of a guideline for the management of the unanticipated difficult airway in pediatric practice. Paediatr Anaesth. 2015;25(4):346-362. PMID: 25684039
23. Navsa N, Tossel G, Boon JM. Dimensions of the neonatal cricothyroid membrane - how feasible is a surgical cricothyroidotomy? Paediatr Anaesth. 2005;15(5):402-406. PMID: 15828992
24. Johansen K, Holm-Knudsen RJ, Charabi B, et al. Cannot intubate-cannot oxygenate - a pediatric mannequin study of emergency front-of-neck access. Paediatr Anaesth. 2017;27(1):73-80. PMID: 27779364

Complications

25. Brantigan CO, Grow JB Sr. Cricothyroidotomy: elective use in respiratory problems requiring tracheotomy. J Thorac Cardiovasc Surg. 1976;71(1):72-81. PMID: 1107564
26. McGill J, Clinton JE, Ruiz E. Cricothyrotomy in the emergency department. Ann Emerg Med. 1982;11(7):361-364. PMID: 7091795
27. Walls RM, Murphy MF. Manual of Emergency Airway Management. 5th ed. Philadelphia: Wolters Kluwer; 2018.
28. Talving P, DuBose J, Inaba K, Demetriades D. Conversion of emergent cricothyrotomy to tracheotomy in trauma patients. Arch Surg. 2010;145(1):87-91. PMID: 20083760

Post-Procedure Care

29. Gillespie MB, Eisele DW. Outcomes of emergency surgical airway procedures in a hospital-wide setting. Laryngoscope. 1999;109(11):1766-1769. PMID: 10569405
30. Fortune JB, Judkins DG, Scanzaroli D, et al. Efficacy of prehospital surgical cricothyrotomy in trauma patients. J Trauma. 1997;42(5):832-836. PMID: 9191664

Australian/NZ Specific

31. Australian Resuscitation Council. ANZCOR Guideline 4 - Airway. 2021.
32. Australian Resuscitation Council. ANZCOR Guideline 11 - Adult Advanced Life Support. 2021.
33. Baker PA, Flanagan BT, Greenland KB, et al. Equipment to manage a difficult airway. Anaesthesia. 2011;66(Suppl 2):45-56. PMID: 22074079
34. Chrimes N, Fritz P. The Vortex approach to airway management. Melbourne: Vortex Approach; 2019.

Training and Simulation

35. Friedman Z, You-Ten KE, Bould MD, Naik V. Teaching lifesaving procedures: the impact of model fidelity on acquisition and transfer of cricothyrotomy skills to performance on cadavers. Anesth Analg. 2008;107(5):1663-1669. PMID: 18931232
36. Petrosoniak A, Ryzynski A, Goffi A, et al. Cricothyroidotomy training: simulation and human cadaver models. Simul Healthc. 2017;12(6):426-432. PMID: 28961599
37. Wong DT, Lai K, Chung FF, Ho RY. Cannot intubate-cannot ventilate and difficult intubation strategies: results of a Canadian national survey. Anesth Analg. 2005;100(5):1439-1446. PMID: 15845702
38. Chang RS, Hamilton RJ, Carter WA. Declining rate of cricothyrotomy in trauma patients with an emergency medicine residency: implications for skills training. Acad Emerg Med. 1998;5(3):247-251. PMID: 9523934

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Appendix: Pre-CICO Checklist

Equipment Preparation for Anticipated Difficult Airway

When difficult airway is anticipated, prepare surgical airway equipment BEFORE induction:

Surgical Airway Trolley:

• Scalpel with size 10 blade (checked, unwrapped)
• Bougie (coudé-tip, 60-70 cm)
• Size 6.0 cuffed ETT (cuff checked)
• 10 mL syringe attached to ETT
• Tracheal hook (optional)
• Small retractors (optional)
• Gauze swabs
• Tape or cotton tie
• Suction (Yankauer, checked)
• Headlight/light source

Adjunct Equipment:

• Ultrasound available for landmark identification
• Backup SGA prepared
• Surgical marker for pre-marking CTM
• Chlorhexidine for skin prep

Team Briefing Template

Pre-Induction Briefing for Anticipated Difficult Airway:

"This patient has features suggesting a difficult airway: [list features].

Our plan is:

• Plan A: Video laryngoscopy with bougie
• Plan B: Supraglottic airway (i-gel size X)
• Plan C: Return to oxygenation via face mask
• Plan D: Surgical cricothyroidotomy

I have pre-marked the cricothyroid membrane. The surgical airway kit is [location].

If I declare CICO, [name] will pass me the scalpel and I will perform front-of-neck access immediately.

Any questions?"

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Appendix: Cognitive Aid for CICO

╔═══════════════════════════════════════════════════════════════╗
║                    CICO COGNITIVE AID                          ║
╠═══════════════════════════════════════════════════════════════╣
║  RECOGNISE:                                                    ║
║  • Failed intubation + Failed SGA + Failed BVM                ║
║  • SpO2 falling despite best efforts                          ║
║  • Patient cannot be oxygenated by any other means            ║
╠═══════════════════════════════════════════════════════════════╣
║  DECLARE:                                                      ║
║  "THIS IS CICO - I AM PERFORMING FRONT OF NECK ACCESS"        ║
╠═══════════════════════════════════════════════════════════════╣
║  ACT:                                                          ║
║  1. PALPATE - Laryngeal handshake, identify CTM               ║
║  2. STAB    - Horizontal incision through skin + membrane     ║
║  3. ROTATE  - Turn blade 90° (handle caudal)                  ║
║  4. BOUGIE  - Slide alongside blade, feel clicks              ║
║  5. TUBE    - Railroad 6.0 ETT over bougie                    ║
║  6. CONFIRM - Capnography, inflate cuff, secure               ║
╠═══════════════════════════════════════════════════════════════╣
║  IF LANDMARKS OBSCURED:                                        ║
║  • 8-10 cm VERTICAL skin incision                             ║
║  • Dissect to cartilage                                       ║
║  • Visualise and palpate CTM                                  ║
║  • Then horizontal incision as above                          ║
╚═══════════════════════════════════════════════════════════════╝

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