Control of the difficult airway
in trauma
The
potential for cervical spine injury makes airway management more complex
in the trauma patient. A cervical spine injury should be suspected in
all injury mechanisms involving blunt trauma. Patients with injury above
the clavicles are at increased risk. Cervical spine injury is often
present and secondary injury to the spinal cord must be avoided. The
head injured patient is sometimes difficult to intubate as usually there
is a gradual reduction in the GCS and the gag reflex remains.
Immobilization of
the cervical spine must remain in place until a complete clinical and
radiological evaluation has excluded any injury to the cord.
- In trauma the
following categories of patients require a definitively secured
airway:
- Apnoea
- GCS <
9 or sustained seizures.
- Unstable
mid-face trauma.
- Airway
injuries.
- Large
flail segment or respiratory failure.
- High
aspiration risk.
- Inability
to otherwise maintain an airway or oxygenation.
- Patients
in Cardio-respiratory arrest.
Airway
Management
Initially the airway should be cleared
of debris, blood and secretions. It should be opened using the 'chin
lift' or 'jaw thrust' or 'triple airway' manoeuvres. The 'sniffing the
morning air' position for standard tracheal intubation flexes the lower
cervical spine and extends the occiput on the atlas. So cervical collar
application before this is essential. If you haven't got a collar to fit
your patient use whatever you can which looks reasonably clean.
Blankets, bags clothing and by-standers.
An oral (Guedel)
or nasopharyngeal airway may be necessary to maintain patency until a
definitive airway is secured. Insertion of an airway produces minimal
disturbance to the cervical spine. Bag and mask ventilation also
produces a significant degree of movement at zones of instability. If a
patient gags on an OP airway don't even get the ET kit ready. They will
not tolerate an ET tube. In this case go with the bag and mask and keep
the resp rate at around 20-25 per minute on high flow oxygen.
Tip!
With a trauma who needs to be intubated try undoing the front
section of a cervical collar to allow the jaw to move forwards during
the push with your laryngoscope. Get your partner to manually hold the
neck and 'c' spine in-line while you do this. Then after a successful
intubation re-fasten the collar.
Unsuccessful
Intubation
Failed or difficult intubation is always a
problem. It is important not to waste time with repeated attempts at
intubation while the patient is desaturating (SPo2). Alternative methods
of securing the airway should be used. (Bag & Mask / OP airway).
Never keep an ET tube in place which you are unsure of. Get it out,
oxygenate, and have another go.
Verification
of Tracheal Tube Placement
It is vital that the position of the tube is confirmed. There are three
things to observe. Firstly, the rise and fall of the chest. Secondly, auscultation.
Listen to the chest on each push on the bag you should hear good air
entry. Thirdly, if the patient has cardiac output you should be
measuring the SPo2 and this reading should remain high. (Although
patients with chest injuries increase the likelihood of mistakes in this
area). Capnography is the measurement of expired Co2 and is usually used
to verify tube position in the Emergency department. Although the first
thing a receiving doctor will do is listen with a stethoscope to the
chest, as you did!
Laryngeal
Mask Airway (LMA)
The LMA is gaining wider support in the
management of patients with cervical spine injury. As well as
maintaining the airway, a tracheal tube (size 6 or less) may be placed,
either blindly or via flexible fibreoptic laryngoscopy. The LMA does not
however protect the airway from aspiration, and by acting as a bolus in
the pharynx, may actually relax the lower oesophageal sphincter and
increase reflux.
Airway management in opiate overdose
This is an area any Paramedic will have come across. You know what I
mean. You intubate, administer high rate O2. You administer Naloxone and
the patient starts to gag and pull on the tube. He would be
shouting but he can't. In suspected opiate or narcotic overdose you may
find the whole situation goes better if you ventilate with the bag &
mask / high O2, give
your patient Naloxone at the same time and providing there is no aspiration then
continue assisted ventilation until your patient comes round.
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