Table of Contents
Nasopharyngeal airway
- Flexible rubber tube which goes through the nose and ends at base of tongue (an adjunct to help keep airway open)
- An oxygen mask or bag-mask ventilation can be applied over the top if needed
- Function: prevents tongue covering epiglottis in patients with reduced GCS. It is better tolerated than oropharyngeal airways in more alert patients.
- Size: 6-7mm diameter for most adults; tube diameter should be similar to nostril size
- Insertion technique:
- Lubricate the nasopharyngeal airway with water-soluble jelly
- Insert into the nostril (preferably right) horizontally along the floor of the nose with a slight twisting action (aim towards the back of the opposite eyeball)
- Confirm airway patency
Oropharyngeal airway (Guedel)
- Rigid plastic tube which sits along top of oral cavity and ends at base of tongue (an adjunct to help keep airway open)
- An oxygen mask or bag-mask ventilation can be applied over the top if needed
- Function: prevents tongue covering epiglottis in patients with reduced GCS
- Size: should be similar to distance between the incisors and the angle of jaw; size 3 (orange) for medium adult
- Insertion technique:
- Ensure no foreign bodies in the mouth
- Lubricate the oropharyngeal airway
- Insert into the mouth upside-down (reduces risk of pushing tongue back) – do not continue if patient gags
- Once tip is around the hard-soft palate junction, rotate 180Ëš and advance the rest of the way
- Confirm airway patency
Supraglottic airway (usually i-Gel)
- Flexible plastic tube with a cuff on the end which sits over top of larynx. Provides some protection against aspiration but does not fully secure airway and can only withstand a small amount of positive pressure ventilation.
- Can be attached to ventilation bag in respiratory arrest; or, during surgery, to ventilator which allows spontaneous ventilation ± low-level positive pressure ventilation supplementation
- Function: airway protection during anaesthetic for surgery (if no risk of aspiration and a muscle relaxant is not required); respiratory arrest; if endotracheal intubation is indicated but fails, or the clinician is not trained in intubation
- Size: 4 (green) for average adult
- Gather equipment
Equipment list
- Supraglottic airway (usually i-gel)
- Water-soluble lubricating jelly
- Tape
- Suction
- Ventilation bag
- Ventilation face mask (will be required if insertion fails)
- Oxygen supply and tubing
- Monitoring: end-tidal CO2 monitor, pulse oximeter, cardiac monitor, blood pressure cuff
- Medications for awake patients (hypnotic and analgesia)
- Insertion technique:
- Give medications if required
- Lubricate outer airway
- Position patient – neck flexed to 15˚, head extended on neck (i.e. chin anteriorly), no lateral deviation
- Standing behind the patient, hold the tube like a pen and insert into the mouth (cuff opening inferiorly), sliding the outer cuff along the palate
- Push back over tongue until it reaches the posterior pharyngeal wall
- Apply pressure to force it backwards and downwards until it reaches the back of the hypopharynx
- The teeth should be between the two black lines on the airway
- Attach ventilation bag/machine and ventilate (~10 breaths/minute) with high concentration oxygen. Observe chest expansion and auscultate to confirm correct placement.
- Consider applying end-tidal CO2 monitor to confirm placement and then secure with bandage or tape
Endotracheal tube
- Flexible plastic tube with cuff on end which sits inside the trachea (fully secures airway – gold standard)
- Attached to ventilation bag/machine
- Function: ventilation during anaesthetic for surgery (if muscle relaxant is required, long case, abdominal surgery, or if head positioning may be required); if patient cannot protect their airway (GCS <8, aspiration risk, muscle relaxation); potential airway obstruction (airway burns, epiglottitis, neck haematoma); inadequate ventilation/oxygenation (e.g. COPD, head injury, acute respiratory distress syndrome)
- Rapid sequence induction intubation = procedural variant using rapid anaesthetisation with cricoid pressure to prevent aspiration while airway is quickly secured – used for patients at risk of aspiration, e.g. non-fasted patients
- Size: 8mm diameter for men, 7mm diameter for women
- Gather equipment
Equipment list
- Laryngoscope (check size – the blade should reach between the lips and larynx – size 4 for most patients), turn on light
- Cuffed endotracheal tube
- 10ml syringe for cuff inflation
- Tape
- Suction
- Ventilation bag
- Ventilation face mask
- Oxygen supply and tubing
- Monitoring: end-tidal CO2 monitor, pulse oximeter, cardiac monitor, blood pressure cuff
- Medications for awake patients (hypnotic, analgesia and short-acting muscle relaxant)
- Laryngoscope technique:
- Give medications if required
- Pre-oxygenate patient with high flow oxygen for 3-5 minutes
- Position patient – neck flexed to 15˚, head extended on neck (i.e. chin anteriorly), no lateral deviation
- Stand behind the head of the patient
- Open mouth and inspect: remove any dentures/debris, suction any secretions
- Holding laryngoscope in left hand, insert it looking down its length
- Passing the tongue
- Slide down right side of mouth until the tonsils are seen
- Now move it to the left to push the tongue centrally until the uvula is seen
- Advance over the base of the tongue until the epiglottis is seen
- Insertion technique:
- Apply traction to the long axis of the laryngoscope handle (this lifts the epiglottis so that the V-shaped glottis can be seen)
- Insert the endotracheal tube via the groove of the laryngoscope so that the cuff passes the vocal cords (male 22-24cm, female 20-22cm)
- Remove laryngoscope and use syringe to inflate the tube’s cuff with the minimum amount of air required for an effective seal
- Attach ventilation bag/machine and ventilate (~10 breaths/minute) with high concentration oxygen. Observe chest expansion and auscultate to confirm correct placement.
- Consider applying end-tidal CO2 monitor to confirm placement
- Secure the endotracheal tube with tape
NB: if it takes more than 30 seconds, remove all equipment and ventilate patient with a bag-mask and high flow oxygen until ready to reattempt intubation.
Tracheostomy
- Surgical hole made in trachea, through which a tracheostomy tube is passed
- Attached to ventilation bag/machine
- Function: a tracheostomy is performed for long-term ventilation in intensive care
- NB: a needle or surgical cricothyroidotomy is different and is used in the emergency setting when an acute upper airway obstruction is preventing endotracheal intubation
Sedation, paralysis, ventilation
- If a patient has had a muscle relaxant they need to be ventilated
- Otherwise the need for ventilation/supplementation of breathing depends on the degree of sedation (a low amount of sedation can allow spontaneous ventilation)
- Patients need to be sedated to a certain degree to allow intubation
- A short-acting muscle relaxant helps endotracheal intubation