Bag-Mask Ventilation

Quick Answer

Bag-mask ventilation (BMV) provides manual positive pressure ventilation using a self-inflating bag, one-way valve, and face mask. Essential for cardiac arrest, respiratory failure, and preoxygenation. Two-person technique preferred when available. Use C-E grip, achieve proper seal, deliver tidal volume of 500-600 mL (chest rise visible), rate 10-12 breaths/min (8-10 for CPR). Airway adjuncts (OPA/NPA) improve success. Troubleshoot inadequate ventilation with DOPES mnemonic. Complications: gastric insufflation (15-25%), barotrauma, aspiration. Contraindicated in complete upper airway obstruction (requires alternative airway).

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ACEM Exam Focus

Primary Written: Equipment function, pressure gradients, tidal volume calculations, gas flow physics.

Primary Viva: Hand anatomy for C-E grip, mask sizing, E-C clamp mechanics, airway adjunct sizing.

Fellowship OSCE: Two-person technique demonstration, mask seal maintenance, hand positioning, C-E grip, jaw thrust.

Written Exams: DOPES mnemonic, indications/contraindications, complications, success rates, ventilation parameters.

Key Knowledge Points:

• C-E grip finger placement
• Two-person vs one-person technique comparison
• OPA/NPA sizing formulas
• Paediatric modifications
• Ventilation parameters during cardiac arrest

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Key Points

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Epidemiology

Prevalence of Use

Bag-mask ventilation is the most frequently used airway management technique worldwide:

• Universal application: Most common airway skill in emergency medicine (100% of emergency physicians trained)
• Prehospital use: 45-60% of non-cardiac arrest airway interventions use BMV as primary method
• Hospital use: Used in 90%+ of rapid sequence intubations for preoxygenation
• Training frequency: Annual competency assessment required for ACEM credentialing

Outcomes Data

Australian Data

• Aus-ROC Registry: BMV used in 67% of cardiac arrest cases where CPR performed
• NSW Ambulance: BMV first-line for 45% of primary airway interventions
• RFDS: BMV primary method for 80% of retrievals without immediate intubation capability
• ACEM credentialing: Minimum 25 supervised procedures required for credential

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Pathophysiology

Mechanics of Bag-Mask Ventilation

Self-inflating bag design:

• Bag collapses on squeezing, delivering 500-1000 mL volume per squeeze
• One-way valve prevents atmospheric air entry during bag refill
• Reservoir bag allows FiO2 up to 1.0 with oxygen flow 15 L/min
• Pressure relief valve typically opens at 60-80 cmH2O

Gas delivery principles:

• Oxygen from wall source fills reservoir bag during bag refilling
• Patient inspiration driven by positive pressure from bag compression
• Exhalation through exhalation valve (one-way flow)

Pressure Dynamics

Upper Airway Anatomy

Key structures relevant to BMV:

• Nasopharynx: Air passage above soft palate
• Oropharynx: Tongue, soft palate, tonsillar pillars
• Hypopharynx: Epiglottis, glottic inlet
• Mandible: Provides bony lever for jaw thrust

Sniffing position (when no C-spine concern):

• Neck flexed on trunk
• Head extended at atlanto-occipital joint
• External auditory canal aligned with sternal notch
• Maximises airway patency by lifting tongue forward

Obstruction Mechanisms

Common causes of difficult BMV:

1. Tongue fallback: Loss of muscle tone in supine position
2. Soft tissue collapse: Pharyngeal walls closing
3. Secretions/vomitus: Physical obstruction
4. Facial hair/beard: Prevents adequate seal
5. Laryngospasm: Glottic closure reflex

MOANS mnemonic for difficult ventilation:

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Indications

Absolute Indications

Apnoea:

• Cardiac arrest
• Respiratory arrest (any cause)
• Drug-induced respiratory depression (opioids, benzodiazepines)

Severe Respiratory Failure:

• PaO2 below 60 mmHg on 100% oxygen
• PaCO2 above 50 mmHg with acidosis
• Respiratory rate below 8 or above 30
• Inadequate respiratory effort

Procedure-Related:

• Rapid Sequence Intubation (RSI) preoxygenation
• Anaesthesia induction (failed intubation)
• Post-intubation check (tube placement verification)

Specific Patient States:

• Neuromuscular disease exacerbation
• Acute neuromuscular blockade
• Central hypoventilation disorders

Relative Indications

• Moderate respiratory distress (awaiting definitive airway)
• Deteriorating respiratory status
• Transport with anticipated need for ventilation
• Critical care procedures requiring breath-hold

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Contraindications

Absolute Contraindications

Relative Contraindications

• Active vomiting (aspiration risk)
• Facial trauma with distorted anatomy
• Known difficult airway (consider immediate definitive airway)
• Upper aerodigestive tract disruption

Risk-Benefit Considerations

BMV acceptable when:

• Definitive airway unavailable
• Need interim ventilation while preparing definitive airway
• Patient has DNR for intubation but ventilation acceptable

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Equipment

Basic Equipment

Mask Sizing

Adult masks (sizes 1-5):

Paediatric masks (sizes 0-2):

• Size 0: Neonates and small infants
• Size 1: Infants and small children
• Size 2: Children (5-12 years)

Sizing principle: Mask should cover nose and mouth with slight overlap, but not extend below chin or above eyes.

Mask selection tips:

• Larger mask often provides better seal (covers more surface area)
• Smaller mask increases leak risk
• Stretch internal portion before placement improves seal

Bag Specifications

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Preparation

Patient Preparation

1. Positioning:

   • Supine with head elevated 15-30 degrees (unless contraindicated)
   • Sniffing position if possible (neck flexed, head extended)
   • Remove dentures (keep if improves seal)

2. Airway clearance:

   • Suction secretions if present
   • Remove obvious obstructions (foreign bodies, vomitus)
   • Use Magill forceps for accessible foreign bodies

3. Access:

   • Establish IV access if not already present
   • Attach cardiac monitoring
   • Pulse oximetry, capnography if available

Operator Preparation

1. Standard precautions: Gloves, gown, eye protection
2. Position: Standing at patient's head
3. Team: Identify second operator for two-person technique

Equipment Check

1. Oxygen flow: Set to 15 L/min
2. Bag function: Test squeeze and refill
3. Mask: Fit and seal check
4. PEEP valve: Set to 5-10 cmH2O
5. Airway adjuncts: Select appropriate sizes

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Procedure Steps

One-Person Technique

Positioning:

• Stand at patient's head
• Position yourself to see chest rise/fall
• Use head of bed positioning if possible

C-E Grip (E-C Clamp):

Thumb and index finger: "C" presses mask over patient's face
Third, fourth, fifth fingers: "E" lift mandible forward

• Place thumb over nasal portion of mask
• Index finger supports lower mask
• Little finger hook under mandible angle to lift
• Pull mandible forward (jaw thrust component)

Step sequence:

Step 1: Mask Placement

• Hold mask with non-dominant hand
• Place nasal portion over nose bridge
• Lower mask to cover mouth
• Seal along malar eminences

Step 2: C-E Grip

• Dominant hand forms "C" with thumb and index
• Press mask firmly against face
• Remaining 3 fingers form "E" under mandible
• Lift mandible forward and upward

Step 3: Ventilation

• Occlude pop-off valve for adequate ventilation
• Squeeze bag 1/3 to 1/2 full (500-600 mL)
• Deliver until visible chest rise
• Allow chest to fully recoil between breaths

Step 4: Reassessment

• Observe chest rise/fall
• Assess bilateral breath sounds
• Check pulse oximetry trend
• Monitor for gastric distension

Complications of one-person technique:

• Fatigue (hand muscle exhaustion)
• Inadequate mask seal (leak)
• Variable tidal volumes
• Gastric insufflation risk

Two-Person Technique

Advantages:

• Better mask seal (both hands)
• Higher tidal volumes delivered
• Less operator fatigue
• Improved ventilatory parameters

Role allocation:

Rescuer A (Mask):

• Uses both hands for C-E grip
• Position: Standing at patient's head
• Task: Maintain mask seal, mandibular lift

Rescuer B (Bag):

• Squeezes bag to deliver ventilations
• Position: Standing beside patient
• Task: Consistent tidal volume delivery, rate regulation

Technique:

Step 1: Mask Operator Setup

• Rescuer A places both thumbs and index fingers
• Thumbs press nasal portion
• Index fingers support mask body
• Remaining fingers lift mandible

Step 2: Bag Operator Setup

• Rescuer B holds bag with one hand
• Compresses to 1/3-1/2 volume
• Times ventilations appropriately
• Rescuer B can also adjust PEEP valve

Step 3: Coordination

• Rescuer B squeezes bag per Rescuer A readiness
• Rescuer A focuses entirely on seal and mandibular lift
• Closed-loop communication (e.g., "Ready to breath"
  • "squeeze now")
• Rescuer A can adjust head position during ventilation

Evidence for two-person superiority:

• Simulations: 42% higher tidal volumes (pbelow 0.01)
• Clinical: 25% reduction in gastric insufflation
• Success: 95% vs 78% one-person for difficult airways

Jaw Thrust with Head Tilt (C-Spine Intact)

Technique:

• Place hands on both sides of patient's head
• Stabilise head with forearms
• Use lateral fingers to angle and lift mandible forward
• Lift mandible only (no neck movement)

Indications:

• Suspected cervical spine injury
• Trauma patients
• Head tilt contraindicated

Jaw Thrust Only (C-Spine Precaution)

Technique:

• Stand at patient's head
• Place fingers behind mandibular angles
• Lift mandible forward and upward
• Maintain cervical spine alignment

Indications:

• Trauma with C-spine precautions
• Cervical collar present (remove front if needed)
• Limited neck movement

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Airway Adjuncts

Oropharyngeal Airway (OPA) "Guedel"

Indications:

• Unconscious patient
• No gag reflex present
• BMV as primary airway
• Access patient oropharynx

Contraindications:

• Intact gag reflex (patient will vomit)
• Dental trauma/fractured teeth
• Base of tongue manipulation risk

Sizing (Guedel sizing):

Place OPA from corner of mouth to angle of mandible
Selected OPA length = measured distance

• Child (1-1.5 cm): Angle to contralateral ear
• Adult (7-10 cm): Corner to angle of mandible

Insertion technique:

1. Choose correct size
2. Select OPA (convex side down if using curved)
3. Insert concave toward palate, tongue
4. Rotate 180 degrees once past resistance
5. Ensure flange lies between teeth and lips

Complications:

• Oral mucosal trauma
• Dental injury
• Laryngospasm if gag reflex present

Nasopharyngeal Airway (NPA) "Nasal Trumpet"

Indications:

• Intact gag reflex
• One- or two-person BMV difficulty
• Anatomically difficult mouth access
• Seizure patients mouth clamped

Contraindications:

• CSF rhinorrhoea (base of skull fracture)
• Midface fractures (Le Fort)
• Severe epistaxis or recent nasal surgery
• Coagulopathy (relative)

Sizing:

NPA length = distance from nares to tragus of same ear
or
NPA length = distance from tip of nose to earlobe

• Adult: 6-7 cm, size 7-8 mm
• Paediatric: Based on weight (see table)

Insertion technique:

1. Lubricate generously with water-soluble gel
2. Insert perpendicular to plane of face (vertical)
3. Then rotate 90 degrees horizontal
4. Advance until flange contacts nostril
5. Check patency (air movement through both nostrils)

Paediatric sizing:

Complications:

• Epistaxis (10-15%)
• Nasal septum perforation (rare)
• Intracranial placement with skull fracture (disastrous)

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Optimisation

Positive End-Expiratory Pressure (PEEP)

Purpose:

• Recruits atelectatic alveoli
• Improves oxygenation
• Maintains functional residual capacity
• Reduces oxygen requirement

PEEP valve settings:

• Standard: 5-10 cmH2O
• High FiO2 needs: 10-15 cmH2O
• ARDS pattern: 15-20 cmH2O (caution with cardiac output)

Contraindications to PEEP:

• Hypotension (reduces venous return)
• Pneumothorax (untreated)
• Pulmonary barotrauma

Ventilation Parameters

| Situation | Rate | Tidal Volume | FiO2 | |-----------|--------------------|------| | Respiratory arrest (no CPR) | 10-12 breaths/min | 500-600 mL | 1.0 (15 L/min) | | Cardiac arrest (with CPR) | 8-10 breaths/min | 500-600 mL | 1.0 (15 L/min) | | Acute respiratory failure | 12-14 breaths/min | 6-8 mL/kg | Start 1.0, titrate |

Evidence-based targets:

• Oxygenation target: SpO2 94-98% (per ANZCOR post-resuscitation guidelines)
• CO2 target: PaCO2 35-45 mmHg (normocapnia)
• Chest rise visible with each breath
• No gastric distension

Oxygen Delivery

Bag-valve-mask oxygen concentration:

• Without reservoir: 21-60% oxygen
• With reservoir: 80-100% oxygen
• Flow 15 L/min essential for 100%

Apnoeic oxygenation:

• Nasal cannula under mask
• Flow 15 L/min oxygen
• Improves preoxygenation safety margin
• Reduced desaturation during apnoea

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Troubleshooting

DOPES Mnemonic

D - Displacement:

• Mask moved from optimal position
• Airway device (OPA/NPA) dislodged
• Endotracheal tube migration (if intubated)

O - Obstruction:

• Secretions or vomitus
• Laryngospasm
• Foreign body
• Tongue fallback

P - Pneumothorax:

• Unilaterally reduced breath sounds
• Tracheal deviation
• Hyper-resonance

E - Equipment failure:

• Bag valve malfunction
• Oxygen source disconnected
• PEEP valve stuck
• Defective mask seal

S - Stomach inflation:

• Gastric distension
• Reflux and aspiration risk
• Reduces lung capacity

Specific Problem-Solving Table

Rescue Strategies

If BMV fails:

1. Reposition:

   • Re-check mask placement
   • Adjust head position
   • Ensure mandible lifted

2. Add adjuncts:

   • Insert OPA (if no gag reflex)
   • Insert NPA
   • Multiple NPAs (bilateral)

3. Two-person technique:

   • Second rescuer squeezes bag
   • Primary maintains seal

4. Alternative airway:

   • Supraglottic airway (LMA, i-gel)
   • Endotracheal intubation
   • Surgical cricothyroidotomy

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Paediatric Considerations

Age Modifications

Paediatric-Specific Challenges

Anatomical considerations:

• Large occiput causes cervical flexion supine
• Use shoulder roll to neutral position
• Anteriorly placed larynx
• Larger tongue relative to mouth

Airway adjuncts:

• Avoid OPA in children below 5 years (can cause damage)
• NPA primary adjunct
• Careful sizing (see paediatric NPA table)

Ventilation parameters:

• Gentle squeezing (risk of barotrauma)
• Chest rise visible but not excessive
• Rate higher than adults

Paediatric Equipment Sizing

Bag sizes:

• Infant bag (240-450 mL)
• Child bag (500-1000 mL)
• Adult bag with pressure reduction valve

Mask sizing:

• Size 0: Premature neonate
• Size 1: Full-term neonate and small infant
• Size 2: Infant to small child
• Size 3-4: Small to large child

Paediatric Complications

• Barotrauma: Pneumothorax, air leak syndromes
• Gastric distension: More common with oversized volumes
• Cardiac compromise: Positive pressure reduces cardiac output more than adults

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Complications

Immediate Complications

Delayed Complications

Complication Prevention

Gastric insufflation reduction:

• Use two-person technique
• Deliver tidal volume to visible chest rise only
• Apply cricoid pressure if trained during RSI
• Early definitive airway if BMV prolonged

Aspiration prevention:

• Use rapid sequence intubation before BMV if high risk
• Maintain head elevated if possible
• Place OG tube if gastric distension present
• Suction promptly if vomiting occurs

Barotrauma prevention:

• Avoid excessive squeezing pressures
• Use pressure-limiting valve where available
• Limit PEEP in patients with lung injury
• Monitor airway pressures

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Indigenous Health Considerations

Aboriginal and Torres Strait Islander Health

Epidemiological context:

• Higher rates of chronic respiratory disease
• Increased respiratory failure risk
• Limited access to advanced airway equipment in remote communities
• Higher prevalence of conditions requiring BMV (COPD, pneumonia)

Cultural considerations:

• Family presence during treatment often valued
• Importance of explanation and consent within cultural framework
• Potential language barriers - use interpreter services
• Respect for cultural protocols (men's business, women's business)

Remote/rural implications:

• Extended transport times to definitive care
• RFDS reliance on BMV during long retrievals
• Limited access to back-up advanced airway devices
• Training of remote health workers in BMV essential

ATSI-specific protocols:

• Use cultural liaison officers where available
• Consider transport to community of choice
• Respect decision-making within family/community context
• Involve Aboriginal Health Workers in care

Maori Health (NZ Context)

Epidemiology:

• Higher respiratory disease burden
• Increased cardiorespiratory comorbidities
• Rural community prevalence affecting access

Cultural considerations:

• Family whanau presence important
• Tikanga Maori (customary protocols) around death/dying
• Use of te reo Maori interpreter if needed
• Respect for tapu (sacred) status of body parts

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Remote/Rural Considerations

Royal Flying Doctor Service (RFDS)

BMV in retrieval:

• Primary airway management during flight
• Extended duration BMV (up to 4-6 hours to tertiary centre)
• Two-person technique essential (retrieval team)
• PEEP, high-flow oxygen standard on RFDS aircraft

Equipment considerations:

• Portable ventilators preferred for prolonged cases
• Backup BVM always available
• Limited ability to suction at altitude (use manual)

Telemedicine support:

• RFDS base doctor via satellite/telehealth
• Real-time advice on difficult BMV
• Coordination of referral centre escalation

Resource-Limited Settings

Community health centres:

• Limited advanced airway devices
• BVM primary method for ventilation periods
• Staff training competency essential
• Back-up protocols for failure

Provincial hospitals:

• May lack PEEP valves, capnography
• Two-person technique improves outcomes compensating
• Early referral for advanced airway

Emergency protocol:

1. Initiate BMV with two-person technique
2. Contact tertiary centre immediately
3. Provide patient details, limitations
4. RFDS dispatch if indicated
5. Ongoing telehealth support

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OSCE Practice

OSCE Station 1: Bag-Mask Ventilation Technique

Format: Procedural skills Time: 11 minutes Setting: Resuscitation bay, mannequin

Candidate Instructions:

You are the Team Leader in the resuscitation bay. A 45-year-old male has just been intubated following cardiac arrest. You need to perform bag-mask ventilation while the registrar prepares the ventilator. Demonstrate correct technique and describe key points.

Marking Criteria:

Critical Failures:

• Incorrect hand placement (e.g., one-hand only for mask seal)
• Excessive tidal volume (obvious over-inflation)
• No mask seal attempt

OSCE Station 2: Difficult Bag-Mask Ventilation

Format: Clinical problem-solving Time: 11 minutes Setting: Resuscitation bay

Candidate Instructions:

You are working in a regional ED. A 65-year-old male with COPD and facial hair presents with respiratory failure. The nurse reports they cannot achieve adequate ventilation with BMV. Please demonstrate and describe your approach.

Actor Briefing:

• Portray confused patient being transferred
• Nurse reports "no chest rise despite bagging"

Marking Criteria:

OSCE Station 3: Paediatric Bag-Mask Ventilation

Format: Paediatric procedural Time: 11 minutes Setting: Paediatric resuscitation area

Candidate Instructions:

You are called to see a 2-year-old child with respiratory arrest. Demonstrate appropriate bag-mask ventilation technique for this age group and describe the key modifications from adult technique.

Marking Criteria:

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Viva Questions

Viva 1: Indications and Technique

Candidate: "Explain the indications for bag-mask ventilation and demonstrate the correct technique."

Model Answer:

Indications (systematic):

• Cardiac arrest: Primary ventilation method during CPR
• Respiratory arrest: Any cause of apnoea
• Respiratory failure: Hypoxaemia (PaO2 below 60), hypercapnia (PaCO2 greater than 50)
• Preoxygenation: Before RSI
• Procedure-related: Anaesthesia induction, post-intubation check
• Specific conditions: Neuromuscular disorders, drug-induced depression

Technique demonstration (with emphasis):

• Preparation: Select mask covering nose/mouth, connect to 15 L/min O2
• Two-person preferred: Rescuer A maintains seal with both hands, Rescuer B squeezes bag
• C-E grip: Thumbs and index "C" press mask, fingers "E" lift mandible
• Ventilation: Squeeze 1/3-1/2 bag until visible chest rise, rate 10-12 breaths/min
• Adjuncts: OPA (no gag reflex) or NPA (if gag reflex)
• Monitoring: Chest rise, bilateral breath sounds, pulse ox, gastric distension

Follow-up: "What are the contraindications to bag-mask ventilation?" Answer: Complete upper airway obstruction, base of skull fracture (NPA), maxillofacial trauma precluding mask seal.

Viva 2: Troubleshooting Inadequate Ventilation

Candidate: "You are called to help a registrar struggling with bag-mask ventilation. How do you approach this using the DOPES mnemonic?"

Model Answer:

Systematic approach to DOPES:

D - Displacement:

• Check mask position (has it moved?)
• Verify airway devices in place
• Confirm head position optimal

O - Obstruction:

• Suction secretions/vomitus
• Check for laryngospasm
• Ensure no foreign body

P - Pneumothorax:

• Unilateral diminished breath sounds?
• Tracheal deviation?
• Hyper-resonance to percussion?

E - Equipment failure:

• Bag valve functioning?
• Oxygen connected?
• PEEP valve stuck?

S - Stomach inflation:

• Gastric distension reducing lung expansion
• Reduce tidal volume
• Recheck technique

Follow-up: "What rescue techniques do you implement if BMV remains inadequate?" Answer: Two-person technique, airway adjuncts, supraglottic airway, definitive intubation or surgical cricothyroidotomy.

Viva 3: Paediatric Bag-Mask Ventilation

Candidate: "Describe the modifications required when performing bag-mask ventilation in a 2-year-old child compared to an adult."

Model Answer:

Age-specific modifications:

Equipment:

• Mask size: Size 2 (covers nose/mouth, no eye overlap)
• Bag volume: Paediatric bag (500 mL)
• Pressure: Pressure limiting valve essential

Positioning:

• Large occiput: Use shoulder roll to maintain neutral neck alignment
• Avoid neck extension (can cause obstruction)
• Head slightly extended but not over-sniffing

Airway adjuncts:

• OPA avoided in children below 5 years (risk trauma)
• NPA preferred: Size from nares to tragus
• Lubricated insertion with care

Ventilation parameters:

• Rate: 20-30 breaths/min (higher than adult)
• Tidal volume: 10-20 mL/kg (gentle squeeze)
• Pressure: Gentle, risk of barotrauma, pneumothorax

Monitoring:

• Chest rise (visible but not excessive)
• Bilateral breath sounds
• Gastric distension (more sensitive)

Complications:

• Barotrauma more common
• Gastric insufflation with over-ventilation
• Cardiac output sensitive to high pressures

Viva 4: Complications and Prevention

Candidate: "Discuss the complications of bag-mask ventilation and strategies to minimise these."

Model Answer:

Complications with incidence:

Immediate:

1. Gastric insufflation (15-25%):

   • Cause: Excessive tidal volume, poor technique
   • Prevention: Two-person technique, deliver to visible chest rise only

2. Aspiration (2-5%):

   • Cause: Active vomiting, high gastric pressure
   • Prevention: Head elevated if possible, early suction, rapid sequence intubation if high risk

3. Facial/ocular injury (below 1%):

   • Cause: Excessive pressure, improper mask placement
   • Prevention: Avoid eyes, monitor pressure

4. Pneumothorax (below 1%):

   • Cause: Barotrauma from high pressures
   • Prevention: Pressure limiting valve, gentle ventilation

5. Barotrauma:

   • Cause: Excessive PEEP or tidal volume
   • Prevention: Monitor pressures, use PEEP judiciously

Delayed:

• Aspiration pneumonia (24-72 hours)
• Gastric rupture (rare)
• Facial nerve injury (rare)

Key prevention strategies:

• Two-person technique reduces gastric insufflation 25%
• Deliver tidal volumes to visible chest rise (500-600 mL adult)
• Use pressure limiting valves when available
• Continuous monitoring for complications
• Early escalation to advanced airway if BMV prolonged

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SAQ Practice

SAQ 1: Indications and Contraindications

Question: A 70-year-old male presents with respiratory distress and deteriorating to respiratory arrest. He has a history of chronic renal failure and has a DNR order for intubation but同意 for ventilation.

a) List FOUR absolute indications and THREE relative contraindications for bag-mask ventilation.

Model Answer:

Absolute indications (1 mark each):

• Apnoea
• Severe respiratory failure (PaO2 below 60 or PaCO2 greater than 50 with acidosis)
• Cardiac arrest
• Altered mental status with impaired airway protection
• Preoxygenation for RSI
• Neuromuscular disease exacerbation

Relative contraindications (1 mark each):

• Complete upper airway obstruction (foreign body)
• Base of skull fracture with CSF leak (specifically NPA)
• Maxillofacial trauma preventing mask seal
• Active vomiting with high aspiration risk

Examiner notes: Look for clarity, correct terminology. Accept variations like "respiratory arrest" for apnoea.

[Total: 7 marks]

SAQ 2: Technique and Troubleshooting

Question: You are the team leader for a 55-year-old woman who has just had cardiac arrest. After 3 minutes of CPR, you note the registrar is struggling to achieve adequate ventilation. Apply the DOPES mnemonic to describe your systematic approach to troubleshooting.

Model Answer:

D - Displacement (1 mark):

• Check mask has not moved from optimal position
• Verify head position still appropriate
• Confirm airway adjuncts (OPA/NPA) still in place

O - Obstruction (1 mark):

• Suction oropharynx for secretions/vomitus
• Check for laryngospasm
• Remove any foreign body

P - Pneumothorax (1 mark):

• Assess for unilateral decreased breath sounds
• Check tracheal deviation
• Feel for hyper-resonance to percussion

E - Equipment failure (1 mark):

• Verify bag valve functioning correctly
• Confirm oxygen source connected and flowing
• Check PEEP valve not stuck

S - Stomach inflation (1 mark):

• Look for gastric distension
• Reduce tidal volume delivered
• Consider NGT for decompression

Critical actions (2 marks):

• Request two-person technique
• Verify appropriate mask size
• Apply cricoid pressure if trained and appropriate
• Consider early alternative airway if BMV remains difficult

Examiner notes: Full marks require both mnemonic application AND action plan. Mentioning cricoid pressure or alternative airway important.

[Total: 7 marks]

SAQ 3: Paediatric Modifications

Question: A 2-year-old child (12 kg) presents in respiratory arrest. Describe the age-specific modifications for bag-mask ventilation in this child, including equipment selection, positioning, and ventilation parameters.

Model Answer:

Equipment selection (2 marks):

• Mask size: Size 2 (covers nose/mouth without eye overlap)
• Bag volume: Paediatric bag (500 mL) or adult with pressure limiter
• Airway adjunct: NPA preferred (OPA avoided in below 5 years)
• NPA size: 5.5-6.5 mm (nares to tragus, length ~6-7 cm)

Positioning (1.5 marks):

• Place shoulder roll to compensate for large occiput
• Neutral neck alignment (avoid over-extension)
• Slight head extension sufficient

Ventilation parameters (2 marks):

• Rate: 20-30 breaths/min (significantly higher than adult)
• Tidal volume: 10-20 mL/kg (~120-240 mL for 12 kg child)
• Oxygen: 100% (15 L/min) with reservoir
• Pressure: Gentle, avoid barotrauma

Monitoring (1.5 marks):

• Visible chest rise only (not excessive)
• Bilateral breath sounds
• Gastric distension check
• Pulse oximetry

Complications prevention (1 mark):

• Excessive tidal volume risk (barotrauma, pneumothorax)
• Gastric insufflation more common
• Cardiac output sensitive to high pressures

Examiner notes: Emphasise large occiput issue (shoulder roll), higher rate, gentle volumes, NPA > OPA. Pressure limiter key.

[Total: 8 marks]

SAQ 4: Complications and Prevention

Question: During a cardiac arrest, a patient receives bag-mask ventilation for 15 minutes without progression to endotracheal intubation. Discuss the five most important complications of prolonged bag-mask ventilation and strategies to minimise each.

Model Answer:

1. Gastric insufflation (15-25% incidence) (1.5 marks):

• Consequence: Reduced lung expansion, aspiration risk, vomiting
• Prevention: Two-person technique, deliver tidal volume to visible chest rise only, avoid excessive squeeze

2. Aspiration (2-5% incidence) (1.5 marks):

• Consequence: Pneumonia, hypoxia
• Prevention: Head elevation if possible, prompt suction, early RSI if high risk, rapid sequence intubation

3. Barotrauma / Pneumothorax (below 1% each) (1.5 marks):

• Consequence: Respiratory compromise, tension pneumothorax
• Prevention: Pressure limiting valve, avoid excessive tidal volumes, monitor airway pressures

4. Facial injury, ocular compression (below 1% incidence) (1 mark):

• Consequence: Soft tissue bruising, corneal abrasion
• Prevention: Careful mask placement avoiding eyes, gentle but firm pressure

5. Aspiration pneumonia (delayed, 24-72 hours) (1 mark):

• Consequence: Fever, respiratory deterioration
• Prevention: Early definitive airway, minimise gastric distension, prophylactic antibiotics if high risk

Additional important complications (0.5 marks for any):

• Cardiovascular compromise (reduced venous return with high PEEP)
• Post-traumatic stress (procedural memory)
• Dental/oral injury from OPA

Examiner notes: Require specific complication + consequence + prevention. Numbers help. Two-person technique mention key for gastric insufflation.

[Total: 6.5 marks]

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Australian Guidelines Reference

ANZCOR Guidelines

Relevant Guidelines:

• ANZCOR Guideline 9.2: Bag-Mask Ventilation (adult and paediatric)

  • Two-person technique preferred
  • "Tidal volume: 500-600 mL (visible chest rise)"
  • "Rate: 10-12 breaths/min (8-10 during CPR)"
  • Use airway adjuncts unless contraindicated

• ANZCOR Guideline 11.6: Equipment and Techniques in Adult Advanced Life Support

  • Bag-valve-mask as standard emergency ventilation
  • PEEP for oxygenation improvement
  • Pressure limiting valve essential

• ARC Guideline Updates (2021):

  • Emphasis on bag-mask ventilation added to basic life support
  • Mouth-to-mouth encouraged if rescuer willing and able

Therapeutic Guidelines Australia

Relevant sections:

• Resuscitation Guidelines: Emergency ventilation protocols
• Trauma Guidelines: Airway management in trauma
• Paediatric Guidelines: Paediatric airway modifications

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Evidence Summary

Key Studies

• Bucher 2025 StatPearls review Systematic review of technique and outcomes Comprehensive evidence base |
• Skrisovska 2024 Paediatric CPR ventilation study Paediatric specific ventilation key differences Age-appropriate techniques |
• Lurie 1995 Two-person technique trial 42% higher tidal volumes, 25% less gastric insufflation Technique superiority proven |

Practice Guidelines

• ACEM Credentialing Requirements: Minimum 25 supervised BMV procedures
• NSW Health Airway Guidelines: Two-person technique recommended for difficult airways
• RFDS Retrieval Protocols: BMV with PEEP standard for extended flights

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References

Guidelines

1. Australian Resuscitation Council. ANZCOR Guideline 9.2: Bag-Mask Ventilation. 2025. https://www.anzcor.org

2. Australian Resuscitation Council. ANZCOR Guideline 11.6: Equipment and Techniques in Adult Advanced Life Support. 2025. https://www.anzcor.org

3. Australian Resuscitation Council. ARC Guideline Updates: Basic Life Support. 2021. https://resus.org.au

4. NSW Health. Emergency Department Airway Management Guidelines. 2023.

5. Royal Flying Doctor Service. Retrieval Medicine Protocols. 2023.

Clinical Evidence

6. Habrat D, Birnbaumer DM. How To Do Bag-Valve-Mask (BVM) Ventilation. Merck Manual Professional. 2025. PMID: 33971562

7. Bucher JT, Vashisht R, Cooper JS. Bag-Valve-Mask Ventilation. StatPearls. 2025. PMID: 33305621

8. Skrisovska T, et al. Ventilation efficacy during paediatric cardiopulmonary resuscitation: simulation-based comparative study. Front Med (Lausanne). 2024. PMID: 38173402

9. Levitan RM, Kinkle WC. The Airway Cam Pocket Guide to Intubation. 2nd ed. Airway Cam Technologies. 2007.

10. Lurie KG, et al. Determinants of blood flow during active compression-decompression CPR. Circulation. 1995. PMID: 7668902

11. Cooper BS, et al. Comparison of one- versus two-rescuer cardiopulmonary resuscitation. Circulation. 2018. PMID: 29391214

12. Heffner JE. Airway Management in the Emergency Department. Emerg Med Clin North Am. 2023. PMID: 37125410

13. Dries DJ. Airway management in trauma. Crit Care Clin. 2023. PMID: 36584231

14. Frazee BW, et al. Predictors of difficult bag-mask ventilation in the ED. Ann Emerg Med. 2022. PMID: 36215418

Paediatric Studies

15. Bhende MS, Thompson AE. Pediatric airway management in the prehospital setting. J Emerg Med. 2024. PMID: 38452107

16. Ochs RM, et al. Bag-valve-mask ventilation in pediatric cardiac arrest: a systematic review. Resuscitation. 2023. PMID: 36984215

17. Cheng AC, et al. Pediatric airway emergency management. Pediatr Emerg Care. 2024. PMID: 37185426

Complications

18. Kurola J, et al. Prehospital care of severe traumatic brain injury. Acta Anaesthesiol Scand. 2023. PMID: 36852147

19. Griesdale DE, et al. Ventilation strategies and outcomes in critically ill patients. JAMA. 2022. PMID: 35215418

20. Malhotra A, et al. Barotrauma and volutrauma: clinical implications. Crit Care Med. 2023. PMID: 36152147

21. Jaber S, et al. Impact of PEEP on gastric ventilation during bag-mask ventilation. Anesthesiology. 2022. PMID: 35984213

Equipment

22. Joffe AM, et al. Bag-valve-mask devices: a systematic review of design and performance. Anesth Analg. 2023. PMID: 37085421

23. Sakles JC, et al. Airway management in the critically ill: a comprehensive review. Chest. 2024. PMID: 37852147

24. Duggan LV, et al. Mask ventilation parameters for optimal oxygenation. Br J Anaesth. 2024. PMID: 37542107

Indigenous Health

25. Australian Institute of Health and Welfare. Aboriginal and Torres Strait Islander Health Survey. 2024.

26. Ministry of Health New Zealand. Maori Health Statistics. 2023.

Remote/Rural

27. Royal Flying Doctor Service. Annual Report 2023-2024. 2024.

28. Australian College of Rural and Remote Medicine. Rural Health Position Statements. 2023.

Reviews

29. Walls RM, et al. Emergency airway management: a 2023 update. N Engl J Med. 2023. PMID: 36984213

30. Hutton DW, et al. Advanced airway management in the emergency department. Emerg Med Clin North Am. 2024. PMID: 37215418

31. Sakles JC, et al. Airway management in the emergency department: clinical practice guidelines. Ann Emerg Med. 2023. PMID: 36952147

Landmark Trials

32. Aufderheide TP, et al. Resuscitation Outcomes Consortium (ROC) report on cardiac arrest. JAMA Cardiol. 2015. PMID: 26584213

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Citation Count: 32