Airway and Cervical Spine

The priority during the resuscitation of any severely injured patient is to ensure a clear airway and maintain adequate oxygenation. A pulse oximeter probe should be applied to the patient as soon as possible remembering that peripheral vasoconstriction may make it impossible to obtain a reliable reading. If the airway is obstructed, immediate basic manoeuvres such as suction, chin lift, and jaw thrust may temporarily clear it. A soft nasopharyngeal airway (size 7.0-7.5 mm) may be particularly useful in the semiconscious patient who will not tolerate a Guedel airway. Every patient with multiple injuries should receive high concentration oxygen. In the unintubated, spontaneously breathing patient this should be given with a mask and reservoir bag (FIO2 = 0.85) (Figure TT.3).

It should be assumed that every patient sustaining significant blunt trauma (particularly above the clavicles) has a cervical spine injury, until proven otherwise. Properly trained paramedics will have applied cervical spine immobilisation at the accident scene (Figure TT.3). The most effective method comprises a combination of an appropriately sized semi rigid cervical collar (e.g. Nec-Loc or Stiffneck), and bilateral sandbags or blocks joined with tape or straps across the forehead. Use of a long spine board will minimise movement at the thoraco cervical junction. This combination will virtually eliminate neck flexion, although 30% of normal extension is still possible. If the patient has an unstable cervical spine injury, further movement may result in permanent injury to the cord. Thus, all airway manoeuvres must be performed carefully, and without moving the neck. Mask ventilation can produce at least as much displacement of the cervical spine as that produced by oral intubation. Manual in line stabilisation (MILS) of the neck will minimise movement of the cervical spine during oral intubation (Majernick 1986), but care must be taken to avoid excessive traction which may distract a cervical fracture. The cervical spine cannot be deemed undamaged until the patient has been examined by an experienced clinician and appropriate radiological procedures (lateral, AP, odontoid views) have been completed. A reliable clinical examination cannot be obtained if the patient has sustained a significant closed head injury, is intoxicated or has a reduced conscious level from any other cause.

Figure TT.3

Cervical spine immobilisation with semi-rigid collar, lateral blocks and spine board

In the unconscious patient, or in the presence of haemorrhage (from maxillofacial injuries, for example) the airway must be secured by placing a cuffed tube in the trachea. Other reasons for intubating the trauma patient during the resuscitation phase are to optimise oxygen delivery and to allow appropriate procedures to be performed on patients who are unable to cooperate. The choice of technique for intubating a patient with a suspected or confirmed cervical spine injury will depend on the indication and on the skill and experience of the anaesthetist. If performed with care, tracheal intubation of a patient with a cervical spine injury carries relatively little risk (Crosby, 1992). Awake nasotracheal intubation is advocated by some, particularly in the USA, but the majority of UK anaesthetists would strongly disagree. Problems with the awake nasal method include: bleeding, unrecognised oesophageal intubation, coughing, bronchospasm and/or laryngospasm, and most importantly a high failure rate. Nasal intubation is contra-indicated in the presence of a basal skull fracture because of the risk of accidental intracranial placement.

The technique of choice for emergency intubation of a patient with a potential cervical spine injury is direct laryngoscopy and oral intubation with manual in line stabilisation of the cervical spine, following a period of pre-oxygenation, intravenous induction of anaesthesia, paralysis with suxamethonium and application of cricoid pressure (Figure TT.4). Manual inline stabilisation (MILS) reduces neck movement during intubation but care must be taken to avoid excessive axial traction. Placing the patient's head and neck in neutral alignment will tend to make the view at laryngoscopy worse; in this position one can expect the view of the larynx to be grade 3 or worse in about 20% of patients (Nolan, 1993; Heath, 1994). Intubation will be aided greatly by the use of a gum elastic bougie. Another very useful instrument to use in these circumstances is the McCoy levering laryngoscope; a recent study has shown that, in the presence of MILS, it reduces the incidence of grade 3 or worse views to 5%. If intubation of the patient proves impossible the airway should be secured by surgical cricothyroidotomy. A laryngeal mask may be inserted to provide oxygenation while a surgical airway is obtained. The LMA does not guarantee protection against aspiration and can be regarded as a temporary airway only. Needle cricothyroidotomy, with a 14 G cannula followed by jet insufflation of oxygen from a high pressure source (400 kPa), is an alternative method of providing temporary oxygenation but as with the LMA, will not protect against aspiration.

Figure TT.4

Manual in line stabilisation of the cervical spine during rapid sequence induction (RSI)

Was this article helpful?

0 0
Peripheral Neuropathy Natural Treatment Options

Peripheral Neuropathy Natural Treatment Options

This guide will help millions of people understand this condition so that they can take control of their lives and make informed decisions. The ebook covers information on a vast number of different types of neuropathy. In addition, it will be a useful resource for their families, caregivers, and health care providers.

Get My Free Ebook

Post a comment