Partial Airway Obstruction — Recognition and Management

The correct response to choking depends critically on one distinction: whether the airway is partially or completely obstructed. These two situations require different responses, and responding to a partial obstruction as if it were complete — by immediately attempting back blows and abdominal thrusts — can actually worsen the situation by dislodging a partial obstruction and converting it into a complete one.

Understanding the difference and knowing the correct management for each is essential first aid knowledge.

Partial vs. Complete Obstruction — Key Differences

Feature	Partial Obstruction (Mild)	Complete Obstruction (Severe)
Can speak	Yes — may be difficult but possible	No
Can cough	Yes — cough is forceful	No effective cough; or silent
Breath movement	Some air movement audible	Little or no air movement
Colour	Normal or slightly anxious	Progressively blue (cyanosis)
Response to asking "are you choking?"	Can respond verbally	Nods; unable to speak
Appropriate response	Encourage coughing	Back blows + abdominal thrusts

⚠️ If the person can cough forcefully, do not intervene with back blows or abdominal thrusts. Encourage them to keep coughing. The cough is the most effective method to clear an airway obstruction — an effective cough generates airway pressures exceeding those achievable with back blows. Premature intervention can move the object further or convert a mild obstruction into a severe one.

Causes of Partial Airway Obstruction

Partial obstructions arise from:

Cause	Examples
Food bolus	Piece of food partially obstructing the airway
Foreign body	Small object, especially in children
Oedema (swelling)	Allergic reaction, angioedema, burn
Infection	Epiglottitis, croup, tonsil abscess
Secretions	Thick mucus from infection or neurological condition
Tumour	Laryngeal or tracheal tumour — gradual onset
Laryngospasm	Sudden reflex closure of the vocal cords

Non-food causes of partial obstruction — swelling, infection, tumour — require medical investigation and cannot be cleared by first aid techniques. The management of these is described below.

Managing a Mild (Partial) Obstruction — Foreign Body

When the person can cough effectively:

1. Encourage them to keep coughing — tell them "keep coughing, you're doing the right thing."
2. Do not pat them on the back while they are coughing effectively — this is unnecessary and can distract from the cough effort.
3. Stay with them — monitor whether the cough is effective and whether the obstruction clears.
4. If the cough remains effective for more than a few attempts — the obstruction will likely clear.
5. Call 999 if: the cough becomes ineffective, the person can no longer speak or breath adequately, or if colour changes.

When Partial Obstruction Does Not Clear

If coughing continues without clearing the obstruction:

• The obstruction may be moving but not fully clearing
• The person will tire, cough will become less effective
• As the cough becomes ineffective (quieter, weaker, less forceful), transition to back blows and abdominal thrusts is required

Transition point: When coughing becomes silent, weak, or the person shows signs of distress (clutching throat, blue lips, inability to speak), move to the severe obstruction protocol immediately:

1. Five back blows: Bend the person forward; deliver five sharp blows between the shoulder blades with the heel of your hand.
2. Five abdominal thrusts: Stand behind the person; link hands above the navel and below the sternum; pull sharply inward and upward.
3. Alternate between five of each and check after each cycle if the obstruction has cleared.
4. Call 999 if not already done.

Partial Obstruction from Non-Foreign Body Causes

Allergic Reaction (Angioedema / Anaphylaxis)

Throat and airway swelling from allergic reaction can cause rapidly progressing partial obstruction:

• Signs: Throat tightening sensation, difficulty swallowing, voice changes, anxiety
• Action: If the person has an epinephrine auto-injector (EpiPen), administer it immediately; call 999; do not delay epinephrine for other interventions
• Do not attempt back blows or thrusts — this is not a foreign body; no object can be dislodged

Croup (Children)

A barking cough and stridor (high-pitched breathing sound) in a child, typically under 5:

• Mild croup: Keep the child calm and upright; cool air may help (open window); call NHS 111 or GP
• Severe croup (severe stridor at rest, difficulty breathing, pale or blue): Call 999 immediately
• Do not attempt back blows or thrusts — not a foreign body obstruction

Epiglottitis

Severe throat infection causing sudden swelling of the epiglottis (the flap covering the airway):

• Signs: Sudden severe sore throat, difficulty swallowing, drooling, stridor, high fever
• Action: Call 999 immediately; keep the person upright and calm; do not attempt to look in the throat
• This is a life-threatening emergency that requires hospital airway management

Documenting and Communicating to Emergency Services

When emergency services arrive or when calling 999 for partial obstruction:

• State whether it is a foreign body or suspected swelling/infection
• State the person's current ability to breathe, cough, and speak
• State whether colour changes have occurred
• In children: give the age and note any recent illness (relevant to croup vs. foreign body)

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Quick Reference

Situation	Response
Coughing forcefully, can speak	Encourage coughing; do not intervene
Cough weakening, cannot speak	Start back blows and abdominal thrusts; call 999
Cannot cough or speak	Severe obstruction — back blows and abdominal thrusts immediately
Throat swelling (allergy)	Epinephrine if available; call 999; not a foreign body
Croup (child, barking cough)	Keep calm; upright; call 999 if stridor at rest
Epiglottitis (severe sore throat + drooling)	Call 999 immediately; keep upright; do not examine throat