Rheumatoid Arthritis

Question 1

What is rheumatoid arthritis?

Answer 1

• Rheumatoid arthritis is a chronic, inflammatory autoimmune polyarthropathy.
• It is both systemic and symmetrical, and causes tenosynovitis, loss of cartilage and bony erosions.

Question 2

What are the airway concerns in a patient with RA?

Answer 2

• Atlanto-axial instability/subluxation (anterior ± posterior).
• Subaxial subluxation.
• Cervical spine ankylosis.
• Cricoarytenoid joint dysfunction.
• Temporomandibular joint dysfunction.

Question 3

How would you assess this patient’s airway?
History:

Answer 3

• Note any previous history or documentation of a difficult airway or intubation.
• Take a detailed medical history, focusing on the symptoms specific to rheumatoid arthritis:
• Neck pain/upper limb paraesthesia, suggestive of atlanto-axial instability. Airway manipulation in these patients can lead to
  paralysis or death.
• Neck stiffness (increasing the risk of a difficult airway).
• Dyspnoea/hoarse voice, which may suggest laryngeal involvement.
• Ask the patient about any dental work and review their dental hygiene.

Question 4

How would you assess this patient’s airway?

Examination

Answer 4

• A general examination may reveal risk factors for a difficult airway, including a raised BMI, obvious anatomical deformities and a receding jaw.
• Check the patient’s mouth opening as it may be limited if she has temporomandibular joint dysfunction.
• Examine neck flexion/extension.
• Carry out specific airway tests:
• Mandibular protrusion: the inability to protrude the lower incisors anterior to the upper incisors is associated with an increased risk of difficult laryngoscopy.
• Mallampati: assesses the visibility of the uvula with maximal mouth opening.
• Thyromental distance: <6cm from the thyroid cartilage to the mandible with the neck in extension is suggestive of difficult laryngoscopy.
• Sternomental distance: <12.5 cm from the sternal notch to the tip of the mandible with the neck in extension is suggestive of difficult laryngoscopy.
• Wilson score: uses five elements (BMI, buck teeth, jaw movement, neck movement and receding mandible) to predict the likelihood of a difficult intubation.

Question 5

How would you assess this patient’s airway?

Investigations:

Answer 5

• An X-ray of the cervical spine should be considered in patients with rheumatoid arthritis to assess for atlanto-axial involvement, particularly if the disease is longstanding or if the patient has symptoms such as pain or paraesthesia.
• MRI scan to follow if indicated.
• Nasendoscopy can be considered in patients with suspected laryngeal
  involvement.

Question 6

What is the Wilson score?

Answer 6

5 factors:
- BMI
- Buck teeth
- Neck movement
- Jaw movement
- Receding mandible

• Each factor is given a score out of 2 (where 2 denotes an abnormality) and a total score of more than 1 suggests a difficult intubation may be likely.
• A score of >1 identifies 75% of difficult patients with a false positive rate of 12%.

Question 7

What are the options for a patient who has been identified as high risk for extubation perioperatively?

Answer 7

The Difficult Airway Society extubation algorithm gives four options for patients that are high risk:

• Extubate the patient when they are fully awake.
• Postpone extubation and transfer the patient to the intensive care
  unit.
• Perform a tracheostomy for a definitive airway.
• Advanced airway techniques, including exchanging the endotracheal
  tube for a laryngeal mask airway; using a remifentanil infusion while extubating; or using an airway exchange catheter in case the patient needs re-intubation rapidly.