Face masks

Ideally, facemasks should be clear to allow you to see:

• The child's colour, and
• The possible presence of vomit.
• Some masks conform to the anatomy of the child's face and make providing a good seal relatively easy. These masks also have a relatively low dead space.
• Circular soft plastic masks also give an excellent seal and are available across a range of sizes - from those designed to fit small neonates through to masks for large adults. Try to store a wide variety of sizes.
• The correct size mask is one which fits over the mouth and nose but does not press on the eyes.

A guide to sizes of Laerdel silicone face masks 00 and 0/1 - Neonate - infant 2 - infant - small children 3 - small - large children 4 - Adult 5 - Large adult:

Jaw thrust

Jaw thrust manoeuvre:

• Jaw thrust is achieved by placing two or three fingers under the angle of the mandible bilaterally, and lifting the jaw upwards, ensuring the maintenance of in-line immobilisation.
• Jaw thrust acts to lift the tongue off the back of the pharynx and so clear the airway.
• This technique may be easier if the rescuer's elbows are resting on the bed or surface the child is lying on.

Oropharyngeal Airway Insertion (OPA)

• An OPA is indicated if the jaw thrust manoeuvre has failed to correct airway obstruction.
• An OPA acts by establishing an opening between the tongue and the posterior pharyngeal wall and can make a difficult airway much easier to manage.
• OPAs may not be tolerated by semi-conscious patients

Guedel airways:

Equipment required

• Lubrication
• Tongue depressor
• Appropriate sized OPA

Sizing

Oropharyngeal airway sizing:

• Measure from the centre of the incisors to the angle of the mandible, when laid on the face concave side up.

Procedure

• Pre-lubricate with either the patient's own saliva or a small amount of lubricating jelly.
• Insertion: >8 years: like an adult: concave side up; pass to the back of the hard palate, then rotate 180^o to concave side down
• <8 years: insert under direct vision, concave side down, using a tongue depressor

Outcome:

• Correction of obstruction
• Improved ventilation
• If ventilation is still insufficient, the patient may require more advanced airway procedures, such as intubation

Endotracheal tube intubation

Indications

Failure to obtain an airway by simple airway opening maneuvers (eg: OPA insertion)

Airway protection (eg: from blood, broken teeth, vomitus)

To provide a secure airway for transport

To control ventilation in the unconscious/head injured patient 

Endotracheal tubes

• Uncuffed tubes are preferable in children up to eight years of age, to avoid oedema at the cricoid ring.
• Finding the right-sized tube is important, to avoid large leaks around the tube.
• Nasotracheal intubation whilst more secure is contra-indicated in patients with possible base of skull fracture

Sizing:

Diameter Neonate - 3.0 mm 0-6 months -3.5mm 6-12 months -4.0 mm Then use (Age in years / 4) + 4 = size of endotracheal tube (ET) mm

Length of insertion at lips:

Visualise the tube passing through vocal cords avoiding endobronchial intubation:

Endotracheal tubes:

Formula for length (at lips) of oral tube is Age/2 + 12

Laryngoscope:

Curved or straight blades can be used although the straight blade laryngoscope is recommended in young children, because:

• It is designed to lift the epiglottis, which is comparitavely large and floppy in children, under the tip of the blade, allowing a better view of the vocal cords; 

Preparation for endotracheal intubation:

• An assistant, who is familiar with intubation equipment, is essential.
• Endotracheal tube: Calculate the appropriate size:Age/4 + 4 mm = internal diameter (ID)

Have tubes of the appropriate size, plus tubes 0.5 mm ID smaller and 0.5 mm ID larger than that size, available on the child's bed.

• Introducer: for ET tubes 4.5 mm ID and smaller, a lightly lubricated stilette 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, and of entering the cranial cavity if there is an undiagnosed fracture of the skull base.
• Laryngoscopes: Have 2 available. Check the light is bright enough.
• Suction: -Check it is working. -Use a Yankauer suction catheter. -Place it next to the child's head.
• Drugs: Draw up and label [see below] -
  • Saline flush 10 ml.
• IV cannula + 3-way tap on extension tubing: all patent and visible
  • Have your assistant ready to:
• Apply Cricoid pressure -Use direct pressure on the cricoid - thumb & index finger both side, and press directly down.
  • Start as the first drug is injected.
  • Don't stop pressure until the ET tube is in place and secure.
• Give Drugs:
  • Hypnotic first, then flush.
  • Muscle relaxant, then flush.
  • Hand you Equipment: In the correct order?

Rapid sequence induction of anaesthesia:

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

1. Pre-oxygenate the child:

• High flow O2;
• Tightly fitting mask;
• Three minutes if possible.

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

• 1st Hypnotic such as thiopentone (3-5mg/kg), midazolam (0.5 mg/ kg) or propofol (2-4 mg/kg);
• 2nd Muscle relaxant such as suxamethonium (1 mg/kg) or rocuronium (1mg/kg).
• Remember, rocuronium is a relatively long acting muscle relaxant and should not be used if intubation is expected to be difficult.
• Hypnotic doses should be at the lower end of the range in hypovolaemic patients. 

3. Intubate the trachea as soon as relaxed; 

Avoid unnecessary bag and mask ventilation prior to intubation as this may inflate the stomach, increasing the risk of aspiration.

Laryngoscope: hold in your left hand. Be gentle.

< 1 year: 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

> 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.
• Don't lever against the teeth.
• Don't jam the lip between blade and teeth

4. Insert the endotracheal tube.

• Calculate how far. [(Age/2) + 12] cm at the teeth.
• Immobilise the tube at the lips.
• Auscultate both axillae and epigastrium to confirm the tube position.
• Secure with cotton tape around the neck, or Elastoplast on the face.

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

6. Check AP chest Xray: 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 - more often, if needed.
8. Humidify the inspired gases using a condenser humidifier (Swedish nose) between the ET tube and the self-inflating bag.
9. Splint the child's arms if necessary (child should be sedated)

Needle cricothyroidotomy

If the airway is completely inadequate, consider:

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

Rationale for needle cyricothyroidotomy

• Patent airway not possible by other means.
• Preferable to surgical airway in children under 12 years of age.
• Useful for obstruction in the larynx or above; not if the obstruction is in the trachea or bronchi.
• It improves oxygenation slightly, buying 10-15 minutes' time for help to arrive and for a definitive airway to be established.

Preparation for needle cricothyroidotomy

• 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 there is no 3-way tap available, cut a 3mm hole in the side of the O2 tubing and, if necessary, cut the O2 tubing to fit over the hub of the cannula.)
• Place a rolled towel under the child's shoulders.

Surface markings

Feel your own cricothyroid membrane: this is the horizontal gap between the thyroid cartilage (Adam's apple) above, and the horizontal cricoid cartilage below.

Surface markings:

• Stand on the child's left and locate the same structures.
• Immobilise the trachea between your left finger and thumb.
• 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.

450 angle:

• Occlude the side hole of the 3-way tap, or the hole in the O2 tubing, for 1 sec, then release for 4 sec to allow expiration.

Complications to be aware of

• Asphyxia
• Aspiration
• Cellulitis
• Oesophageal perforation
• Haemorrhage
• Haematoma
• Posterior tracheal wall perforation
• Subcutaneous and/or mediastinal emphysema
• Thyroid perforation
• Inadequate ventilation leading to hypoxia and death