Paediatric Trauma

RCH > Surgery > Perioperative Services > Paediatric Trauma

1.3 Airway Management

Introduction
How are children different?
Primary survey
Complete airway inadequacy
Specific airway problems in trauma

Introduction

Establishing an airway is the first priority in the management of trauma patients.

This chapter will cover how to assess and manage airway problems in the infant or child trauma patient.

How are children different?

(see chapter 1.1)

Apart from their obvious smaller size and the growing process, children have important physiological differences, relative to adults, which are significant in airway management:

Narrower airways- Hence they are more easily obstructed by oedema, blood foreign bodies.
Larger tongue
Longer floppy epiglottis- As such in infants a straight blade largngoscope is needed for intubation
Higher anterior larynx
Narrower airway at the cricoid just below the larynx
Shorter trachea. Chest film is required to confirm ETT posistion
Larger occiput. This results in the nexk being flexed when a child is lying supine.

In all aspects of trauma management, the primary survey is the first priority

Primary survey

Airway with C-spine immobilisation - assessment and management

Breathing

Look for chest movement (see chapter 1.4)

Listen for air entry at the lips OXYGEN VIA FACE MASK

Feel the child's breath on your cheek. Circulation assessment and management (see chapter 1.5)

Airway assessment

Mechanisms of airway obstruction

Supine posture in an unconscious child;
Displaced teeth;
Foreign body, such as food/vomit/blood/saliva;
Haemorrhage into mouth, tongue, neck;
Burn-associated oedema of mouth, pharynx, larynx.

Signs: of airway obstruction

Restlessness
Cyanosis
Low SpO2
Respiratory distress

Rising respiratory rate
paradoxical movement of the chest and abdomen (2pictures insp and exp- pictures on disk ??)
Use of accessory muscles, sternal, intercostal, subcostal recession

Wheeze or prolonged expiration - intrathoracic obstruction. (e.g. trachea or bronchi)
Stridor - extrathoracic obstruction. (e.g. pharynx, larynx, upper trachea)
Visible swelling of tongue, pharynx or neck
External signs of injury to face, mouth, mandible or neck
Dysphonia.

Mechanisms of airway obstruction

Supine posture in an unconscious child;
Displaced teeth;
Foreign body, such as food/vomit/blood/saliva;
Haemorrhage into mouth, tongue, neck;
Burn-associated oedema of mouth, pharynx, larynx.

Airway management

Immobilise the cervical spine - manual in-line stabilisation: no traction (see chapter 1.12)

Maintain head in neutral position

Infants (up to one year old) have a large occiput, which flexes the neck when the infant lies supine on a flat surface. To achieve a neutral position, place 1-2 folded towels under the trunk, from buttocks to shoulders. This allows the occiput to be 1-2 cm lower than the back, and allows the head to rest in a neutral position.

Open the Airway

In trauma, always use JAW THRUST. (Not head tilt or chin lift) (Place fingers behind the angles of the mandible and lift straight forward (towards the tip of the nose)

Aairway jawthrust

Jaw thrust

Clear the Airway

If you hear gurgling noises due to fluid in the airway, gently suction the pharynx via a soft 10 FG suction catheter (infants) or a Yankauer sucker (older children) under direct vision, using a laryngoscope or a tongue depressor. Try not to touch the mucosa, as this may cause bleeding or laryngospasm.

If an obstruction persists

Optimise the head position, and reopen the airway using a jaw thrust.
Rapidly examine the mouth with a laryngoscope.
Remove any visible foreign body using Magill forceps or Yankauer sucker.
If the airway is adequate during laryngoscopy but inadequate at other times, insert an oropharyngeal airway.

Oropharngeal Airway (OPA)

An airway of the right size reaches from the central incisors to the angle of the child's mandible

BOPA

Sizing of OPA

Guedel airways

Insertion

Child more than 8 years: As for an adult: concave side up; pass to the back of the hard palate, then rotate 180o to concave side down
Child less than 8 years: Insert under direct vision, concave side down, using a tongue depressor.
If the airway remains inadequate: consider tracheal intubation if the facilities are available to do this safely and quickly.

If you are unable to intubate the child whose airway is inadequate:

Send urgently for expert help - ICU Registrar/ENT surgeon/ anaesthetic registrar.
Use jaw thrust and gentle oropharyngeal suction to clear the airway using airway adjuncts, such as Guedel.
Give OXYGEN via facemask and monitor.
If the child has inhaled a foreign body, or has a partly transected trachea or larynx, and is breathing adequately while partly obstructed, don't try to intubate but give O2 by mask. Reassure the child and family and stay with the child until expert help arrives.

Intubation

Indications for Intubation

Airway obstruction persists despite oropharyngeal (Guedel) airway.
Adequate ventilation not possible via bag and mask ventilation;
Needs definitive airway protection;
Unresponsive to painful stimuli
Flaccid limbs, decerebrate/decorticate posturing; GCS ?8.
Needs prolonged ventilation;
Respiratory burn injury.

Preparation for Endotracheal intubation:

Pre-Oxygenate: administer the highest available concentration of oxygen for at least two minutes, while preparing equipment and drugs.

Empty the stomach via orogastric tube and suction if possible

Endotracheal tube:

Size: Age/4 + 4 mm internal diameter (ID);
Tubes of the size calculated above, plus tube 0.5 mm ID smaller and

0.5 mm ID larger, should all be available on the child's bed.

e.g.: 6 year old child: 6/4 + 4 = 5.5mm in diameter.

As such on the child's bed should be 5.0, 5.5 and 6.0 mm in diameter tubes.

endotrachealtubes

Endotracheal tubes

Introducer: For ET tubes 4.5 mm ID and smaller, a lightly lubricated Stiletto (PICTURE) inserted almost to the tip of the tube makes intubation easier. Oral: Always use oral, never nasal, intubation in a child with a head injury (because of the risk of meningitis, or of entering the cranial cavity if an undiagnosed fracture of the skull base is present.

Laryngoscope: Have 2 available; check that the light is bright enough. If not change the battery, if no light at all change the bulb.

Suction:

Check it is working
Ensure it is a Yankauer
Check it is next to the child's head

Drugs: Drawn up and labeled:

Thiopentone
3-5mg/kg in a normovolaemic child
0.5-1mg/kg in a hypovolaemic child
Midazolam
0.3mg/kg in a child
Propofol
2.5mg/kg in a normovolaemic child
1mg/kg in a hypovolaemic child
Suxamethonium
1-2mg/kg in a child
Rocuronium
1mg/kg in a child
Saline flush 10 ml IV cannula + 3-way tap on extension tubing: all patent and visible.

Have your assistant ready to help with: Cricoid pressure

Use direct pressure on the cricoid. With the thumb and index finger on either side of the cricoid, press firmly and directly downwards.
- Start as the first drug is injected.
- Don't stop until the ET tube is in and secure.

Rapid sequence induction of anaesthesia:

Used whenever the stomach may not be empty (i.e. every injured child)

1. Pre-oxygenate the child:

High-flow O2

Tightly fitting mask

5 minutes if possible.

2. Drugs: - Always used unless the child is flaccid and unresponsive.

1st hypnotic: such as thiopentone midazolam or propofol (Use with caution in Hypotension - see side-effects)

2nd muscle relaxant: such as suxamethonium or rocuronium

3. Intubate the trachea as soon as relaxed, to avoid gastric distension and aspiration.

Avoid unnecessary bag and mask ventilation

Laryngoscope:

Hold in your left hand.
Be gentle.
Don't lever on the teeth.
Don't jam the lip between blade and teeth.

Up to 1year: Straight blade (Miller or Robertshaw)

Pass the tip over the tongue, past the tip of the epiglottis
Lift the epiglottis to see the vocal cords.

straight blade laryngoscope

More than 1 year: Curved blade (MacIntosh 2 or 3)

Pass the tip over the tongue into the vallecula (space between tongue and epiglottis)
Lift the handle towards the ceiling at the far end of the room to bring the vocal cords into view.

curved blade laryngo

4. Insert the endotracheal tube

Length [(Age/2) + 12] cm at the teeth.

Immobilise the tube at the lips.

Auscultate both axillae and the epigastrium to confirm tube position.

Secure with cotton tape around neck or Elastoplast on the face.

5. Insert an orogastric tube on free drainage.
Never use a nasogastric tube or a nasotracheal tube in a child with a head injury (because of the risk of meningitis or of entering the cranial cavity where there is undiagnosed fracture of skull base).

6. Check on an AP chest X-ray: The ET tube tip should lie at the level of the medial end of the clavicles. If not, re-position the tube and re-tape.

7. Suction the ET tube carefully each hour, and more often if needed.

8. Humidify the inspired gases using a condenser humidifier (Swedish nose) between the ETT (PICTURE) tube and the self-inflating bag.

9. Splint the child's arms if necessary. (Child should be sedated)

Side effects of drugs

Hypnotics (thiopentone, midazolam, propofol) all cause:
- Hypotension - especially in the presence of hypovolaemia. Give a smaller dose (eg thiopentone 1-2mg/kg) very slowly if the child is hypotensive, and stop injecting when the child's eyelash reflex disappears.
- Respiratory depression - Beware of using IV hypnotics in severe airway obstruction; ensure that you can inflate the chest with bag/mask first.
Muscle relaxants:
- Prevent breathing - Beware of using them in severe airway obstruction; ensure that you can inflate the chest with bag/mask first.
- Suxamethonium acts faster than rocuronium, and much faster than pancuronium, but causes severe hyperkalaemia in crush injury and burns patients (can occur up to 24 hours after burn) this causes fasciculation and severe muscle pain.

Complete airway inadequacy

If the airway is completely inadequate, consider:

Surgical cricothyroidotomy (> 12 years)
Needle cricothyroidotomy (any age; may be used to gain time during surgical cricothyroidotomy)

Needle cricothyroidotomy

(see Chapter 2)

Useful for obstruction in the larynx or above, but not if there is obstruction in the trachea or bronchi. It improves oxygenation slightly, and buys 10-15 minutes' time for help to arrive, and for the establishment of a definitive airway.

Continue bag/mask ventilation with O2
Prepare equipment: -IV cannula: largest available (10 - 16 SWG), with 5 ml syringe
- Oxygen tubing + 3-way tap (if no 3-way tap available, cut a 3 mm hole in the side of the O2 tubing, cutting the O2 tubing if necessary, to fit over the hub of the cannula.
Rolled towel under the child's shoulders;
Feel your own cricothyroid membrane: this is the horizontal gap between the thyroid cartilage (Adam's apple) above, and the horizontal cricoid cartilage below.
Stand on the child's left and locate the same structures.
Immobilise the trachea between your left finger and thumb in the child .
Insert the cannula through the cricothyroid membrane, then 45o downwards towards the feet. STAY IN THE MIDLINE
Aspirate continuously as soon as the needle is through the skin.
When you can aspirate air, the needle is in the trachea; immobilise the syringe (don't pull it back) and slide the cannula down the needle into the trachea.
Tape the cannula in place.
Attach the O2 tubing to the cannula.
Run O2 at 1 litre/min per year of age.
Occlude the side hole of the 3-way tap, or the hole in the O2tubing, for 1 second. Then release for 4 sec to allow expiration.

Surgical cricothyroidotomy:

(see chapter 2)

Continue bag/mask ventilation with O2.
Prepare equipment: -3.5 - 4.5 ET tube -Scalpel blade on a handle - Curved mosquito forceps -Cotton tape or 2/0 silk ties -Self-inflating resuscitation bag attached to O2 outlet.
Rolled towel under the child's shoulders;
Feel your own cricothyroid membrane: this is the horizontal gap between the thyroid cartilage (Adam's apple) above and the horizontal cricoid cartilage below;
Stand on the child's left and locate the same structures;
Immobilise the trachea between your left finger and thumb;
Make a 1.5 cm vertical incision down to the trachea over the cricothyroid membrane;
Spread the skin edges with your finger and thumb;

Stay in the midline

Carefully stab through the cricothyroid membrane with the scalpel blade oriented transversely;
Rotate the blade through 90o to open the hole and keep it in place;
Insert the endotracheal tube straight backwards beside the scalpel; When you feel it enter the trachea, push it downwards into the lower trachea;
Immobilise the tube and tape it in place;
Ventilate with the self-inflating bag +O2
Auscultate both axillae and epigastrium to confirm tube position;
CXR to check tube length;
Orogastric tube on free drainage.

If the lungs do not inflate easily, possible reasons are:

The ET tube is not in the trachea. Most likely cause. Start again!
Bilateral tension pneumothoraces. Less likely: try needle thoracostomy. (link to page ????)
Foreign body completely obstructing the lower trachea. Unlikely: try passing the ET tube further down the trachea.

The main problems of needle and surgical cricothyroidotomy are:

Failure to enter the trachea: hold the trachea firmly and stay in the midline.
Bleeding: Apply pressure with a swab. Tie off large bleeders.
Damage to local structures (oesophagus, pleura causing pneumothorax, arteries, veins, nerves).
Tracheal transection, if too wide an incision is made during surgical cricothyroidotomy.
Damage to the trachea or larynx.
Infection.

Specific airway problems in trauma

Airway injury

Be suspicious in the following injuries:

Fall onto sharp object;
Running/riding into hidden wire;
Motor vehicle accident: A blow from dashboard / front seat;
Penetrating injury to the neck.
In each case consider ruptured larynx or trachea: Look for subcutaneous emphysema

Burn

For definitive burns management see chapter 1.10

Airway management is a priority.

Airway obstruction occurs secondary to:

Thermal injury
Inhalation of flames/steam
Aspiration of hot liquids

Upper airway obstruction can occur due to inhaled smoke even in the absence of burn to the face.
If the child is exposed to fire or smoke in an enclosed space e.g. a building or car, consider inhalation injury until proven otherwise.

Signs of a respiratory burn injury:

Tachyapnoea or rising respiratory rate
Dysphagia or drooling
Stridor
Mouth/neck/facial burn
Oedema of neck and face
Respiratory distress e.g. intercostal or subcostal recession. This is a very late sign and requires immediate tracheal intubation and mechanical ventilation.
Signs of airway obstruction

Primary survey for burn

Airway - protect C-spine if there is any suspicion of airway compromise. Immediately consider tracheal intubation and expert review.
Breathing -give high-flow oxygen. Assess. If there is any sign of respiratory distress, immediately consider tracheal intubation and expert review.

1.3 Airway Management

Introduction

How are children different?

Primary survey

Airway assessment

Mechanisms of airway obstruction

Signs: of airway obstruction

Mechanisms of airway obstruction

Airway management

Maintain head in neutral position

Open the Airway

Clear the Airway

If an obstruction persists

Oropharngeal Airway (OPA)

Insertion

Intubation

Indications for Intubation

Preparation for Endotracheal intubation:

Have your assistant ready to help with: Cricoid pressure

Rapid sequence induction of anaesthesia:

Side effects of drugs

Complete airway inadequacy

Needle cricothyroidotomy

Surgical cricothyroidotomy:

Specific airway problems in trauma

Airway injury

Burn

Primary survey for burn

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