Women may have limited cervical spine movement because of rheumatoid arthritis, ankylosing spondylitis, cervical disc disease, trauma, accessory cervical ribs or cervical spondylosis, although the last is extremely uncommon in women of childbearing age.
A rare but important cause of cervical scoliosis is Klippel-Feil syndrome, in which there is fusion of two or more cervical vertebrae. In extreme cases, the patient may present with severe webbing of the neck, marked scoliosis and virtually no neck movement, but milder cases may pass unnoticed until the woman presents to the anaesthetist in the obstetric theatre.
Problems and special considerations
The major concern of the obstetric anaesthetist is reduced flexibility of the neck and the likelihood of difficulty with tracheal intubation. In addition, there may be other features of the underlying cause of the neck problems (e.g. rheumatoid arthritis). Obstetric management is further complicated by the uncertain mode, timing and urgency of delivery; antenatal review and planning for all possibilities are prudent.
Management options
Whenever possible, women should be identified and assessed antenatally. The woman with limited cervical spine movement should be advised of the potential hazards associated with general anaesthesia and advised to accept epidural analgesia for labour and regional anaesthesia for any proposed operative procedure.
Obstetric and midwifery staff must be aware that patients with potentially difficult airways represent increased anaesthetic risk, and that the anaesthetist should be involved early in any decision that might lead to operative delivery.
If general anaesthesia is essential, the anaesthetist must fully assess the patient pre- operatively (including women presenting for emergency surgery). Basic assessment must include neck movement and mouth opening. If difficulty with intubation is anticipated, senior assistance must be sought before proceeding with induction of general anaesthesia. Local protocols should be followed in the event of unexpected failed intubation (see Chapter 38, Failed and difficult intubation).
All obstetric theatres should have a difficult intubation trolley readily available, with a variety of laryngoscopes, including McCoy and polio blades, and a video laryngoscope. Awake fibreoptic intubation is now thought by many to be the management of choice when general anaesthesia is required in a woman who is known to have significant cervical spine abnormality, although elective preoperative tracheostomy has also been suggested.
Key points
• The main problem posed by cervical spine disorders is potentially difficult tracheal intubation.
• Regional techniques are usually considered best.