A to E: Airway & Breathing

Question 1

How is a compromised airway recognised?

Answer 1

• Reduced GCS
• Look for chest and abdominal movement
  
  • ‘See-saw respiration’
  • Accessory muscles
• Listen and feel for airflow from mouth and nose
• Additional sounds
  
  • Inspiratory stridor
  • Expiratory wheeze
  • Snoring/gurgling

Question 2

List five causes of a compromised airway

Answer 2

• CNS depression
  
  • Head injury; intracerebral disease; hypercarbia; drugs
• Blood; vomit; bronchial secretions
• Foreign body
• Trauma to face/throat
• Epiglottitis
• Pharyngeal swelling
• Laryngospasm
• Bronchospasm
• Blocked tracheostomy or laryngectomy

Question 3

Describe how to manage a compromised aiway

Answer 3

• Call for help
• Airway clearance: (add C-spine control if trauma)
  
  • Head tilt; chin lift; jaw thrust
    
    • Suspected C-spine injury: neutral; avoid head tilt
    • ​Remove foreign bodies with forceps or suction
  • Airway adjuncts
    
    • Oropharyngeal: Incisors to angle of jaw
    • Nasopharyngeal: 6-7mm
  • LMA; i-gel; consider emergency cricothyroidotomy
• High flow (15 L/min) O₂ via non-rebreath mask or self-inflating bag

Question 4

Describe the presentation of mild choking

Answer 4

Choking occurs while eating; may clutch neck

• Speaks
• Coughs
• Breathes

Question 5

Describe the presentation of severe choking

Answer 5

Choking occurs while eating; may clutch neck

• Unable to speak; may nod
• Unable to breathe
• Wheezy breath sounds
• Silent cough
• Unconscious

Question 6

Outline the treatment of choking

Answer 6

• Mild: encourage coughing only
• Severe and conscious: alternating
  
  • Up to five back blows
  • Up to five abdominal thrusts
• Consider forcep removal of foreign body

Question 7

How are breathing problems recognised?

Answer 7

• Complains of dyspnoea; distressed
• Tachypnoea
• History and examination suggestive of lung/chest wall pathology
• Irritability; confusion; reduced GCS: hypoxaemia and hypercarbia
• Cyanosis (late)
• Abnormal SaO₂ and/or ABG/VBG

Question 8

Suggest four causes of breathing inadequacy

Answer 8

• CNS depression
  
  • Head injury; intracerebral disease; hypercarbia; drugs
• Respiratory effort
  
  • Spinal cord lesion
  • NMD: Myasthenia gravis; Guillain-Barre syndrome; multiple sclerosis
  • Generalised weakness; pain
  • Chest wall deformities
• Lung disorders
  
  • Pneumothorax; haemothorax
  • Infection; aspiration; COPD exacerbation; asthma; PE; ARDS

Question 9

Outline the management of breathing problems

Answer 9

• High flow (15 L/min) O₂ via non-rebreath mask
  
  • Once stable, titrate to target SaO₂
    
    • 94-98% normally
    • 88-92% if chronic CO₂ retainer (high HCO₃^-)
• Bag-mask ventilation if low RR; call for help
• Treat underlying causes
• Assess exhaustion and consider need for NIV
  
  • If not improving or GCS 8: contact ITU for ventilator support

Question 10

What are the indications for acute non-invasive ventilation?

Answer 10

• COPD: either
  
  • pH <7.35; pCO₂ >6.5; RR >23
  • Persisting after bronchodilator and controlled O₂ therapy
• Neuromuscular disease: either
  
  • Respiratory illness w/ RR >20 if usual VC <1L
  • pH <7.35 and pCO₂ >6.5
• Obesity: either
  
  • pH <7.35; pCO₂ >6.5; RR >23
  • Daytime pCO₂ >6.0 and somnolent

Question 11

Give three contraindications for non-invasive ventilation

Answer 11

• Severe facial deformity
• Facial burns
• Fixed upper airway obstruction
• pH <7.15
• GCS <8
• Confusion; agitation
• Cognitive impairment