Extra Topic 3.1 -- Rheumatoid Arthritis

Question 1

What are the systemic manifestations of rheumatoid arthritis (RA)?

Answer 1

The systemic manifestations of RA are thought to be due to –

• a vasculitis that develops secondary to the deposition of immune complexes.

Cardiac manifestations include –

• pericardial thickening,
• effusion,
• pericarditis,
• myocarditis,
• aortitis,
• cardiac valve fibrosis,
• myocardial ischemia,
• diastolic dysfunction,
• pulmonary hypertension, and
• formation of rheumatoid nodules in the conduction system leading to cardiac dysrhythmias.

Other systemic manifestations include –

• pleural effusions,
• pulmonary fibrosis,
• interstitial lung disease,
• peripheral neuropathy (i.e. carpal tunnel syndrome),
• liver dysfunction,
• kidney dysfunction, and
• mild anemia.

Joint involvement with the potential to affect laryngoscopy typically includes –

• the cervical spine,
• temporomandibular joint, and
• the crico-arytenoid joints making intubation difficult.

Question 2

What pharmacologic treatment is this patient potentially receiving and how would this change your anesthetic management?

Answer 2

The goals of pharmacotherapy for rheumatoid arthritis (RA) include –

• providing analgesia,
• reducing inflammation,
• producing immunosuppression, and
• inducing remission.

The three groups of drugs commonly used to achieve these goals include:

1. NSAIDs, to provide analgesia and reduce inflammation and swelling;
2. disease modifying antirheumatic drugs (DMARDs) = (methotrexate, sulfasalazine, leflunomide, azathioprine, D-penicillamine, etc.), to slow or halt the progression of the disease; and
3. corticosteroids, to rapidly decrease inflammation until the much slower acting DMARDs begin to bring the illness under better control (usually 2-6 months).

If the patient were taking aspirin or an NSAID, I would evaluate the patient for –

• gastrointestinal complications (gastric ulcers),
• renal complications (renal insufficiency), and
• platelet dysfunction;

adjusting my anesthetic plan based on my findings (drug selection, drug dosing, regional vs. general anesthesia).

If the patient was receiving corticosteroid therapy, I would consider administering perioperative exogenous steroids to compensate for increased perioperative requirements (related to the stress of surgery) and reduce the risk of life-threatening perioperative adrenal insufficiency.

Question 3

Assume that this patient is receiving a DMARD, which potentially increases the risk of infection.

Would you provide supplemental steroids and further increase this risk in a patient who is about to have a total knee replacement?

Answer 3

Given the life-threatening risk of inadequate adrenal function (addisonian crisis),

I would provide perioperative supplementation to anyone who has received the equivalent of 5 mg of prednisone per day (long term suppression of the hypothalamic-pituitary-adrenal axis is unlikely with smaller doses) in the last year

(even topical application of steroids has been demonstrated to potentially depress adrenal function for as long as 9 months to a year).

While there is a real risk of infection with chronic steroid therapy, it is unclear as to whether this risk is further increased with perioperative supplementation.

Moreover, other complications associated with perioperative steroid administration, such as impaired wound healing (although the evidence is inconclusive), hypertension, fluid retention, stress ulcers, and psychiatric disturbances, are rare and/or unproven.

Question 4

How would you evaluate this airway?

Answer 4

Rheumatoid involvement of –

• the cervical spine (atlantoaxial subluxation, limited neck movement),
• temporomandibular joint (limited mandibular movement and mouth opening), and
• crico-arytenoid joints (limited vocal cord movement with narrowed glottic opening, increased risk of crico-arytenoid dislocation),

can lead to difficult airway management.

Therefore, in addition to the normal airway exam, I would perform a focused history and physical examination to identify any signs of involvement in these areas, such as –

• neurologic deficits,
• neck and upper extremity pain,
• headaches,
• limited range of motion in the cervical spine or temporomandibular joint, and
• crunching sounds with neck movement.

As always, I would evaluate the patient’s mouth opening, thyromental distance, tongue size, dentition, and Mallampati score.

If there were evidence of possible cervical spine involvement, placing the patient at increased risk of atlantoaxial subluxation –

(anterior subluxation of C1 on C2 could potentially lead to displacement of the odontoid process into the cervical spine, medulla, and vertebral arteries, precipitating quadriparesis, spinal shock, and death),

I would order anteroposterior and lateral cervical spine radiographs, with flexion, extension, and open-mouth odontoid views.

If the separation of the anterior margin of the odontoid process from the posterior margin of the anterior arch of the atlas exceeded 3 mm, I would consult a neurosurgeon and consider proceeding with regional anesthesia.

If general anesthesia were Required for some reason, I would perform an awake fiberoptic intubation with a cervical collar in place (assuming the consulting neurosurgeon agreed to this course of action).

Question 5

Following surgery the patient complains of bilateral eye irritation and a gritty sensation with blinking.

What do you think is the cause?

Answer 5

Bilateral eye irritation with a gritty sensation when blinking is consistent with –
keratoconjunctivitis,

which occurs with impaired lacrimal gland function and subsequent inadequate tear formation.

This condition, along with xerostomia (from impaired salivary gland function),

is a manifestation of Sjogren syndrome (a condition associated with rheumatoid arthritis) and may lead to drying of the eyes and increased risk for perioperative corneal abrasion.