Ankylosing spondylitis

Learning objectives

Describe ankylosing spondylitis
Recognize the symptoms and signs of ankylosing spondylitis
Anesthetic management of a patient with ankylosing spondylitis

Definition and mechanisms

Ankylosing spondylitis (AS), autoimmune seronegative spondyloarthropathy, is a painful chronic inflammatory arthritis characterized by exacerbations (flares) and quiescent periods
AS primarily affects the spine and sacroiliac joints, eventually causing fusion and rigidity of the spine → bamboo spine
Joint mobility in the affected areas worsens over time
The areas most commonly affected are
- Sacroiliac joints
- Vertebrae in the lower back
- Places where tendons and ligaments attach to bones, mainly in the spine
- Cartilage between the breastbone and the ribs (sternum)
- Hip and shoulder joints
Linked to HLA-B27 gene

Signs and symptoms

Symptoms might worsen (flares), improve, or stop at irregular intervals

Chronic dull pain in the lower back or gluteal region combined with stiffness of the lower back, especially in the morning and after periods of inactivity
Hip pain
Joint pain
Neck pain
Fatigue
Difficulty breathing
Loss of appetite and unexplained weight loss
Abdominal pain and diarrhea
Skin rash
Vision problems

Complications

Spinal compression fractures
Atlanto-axial subluxation possible (21% of AS patients)
Eye inflammation (iritis or uveitis) and sensitivity to light (photophobia)
Fused vertebrae (ankylosis)
Kyphosis (forward curvature of the spine)
Osteoporosis
Cardiovascular abnormalities: Aortic insufficiency/aortitis, arrhythmias, angina, cardiomyopathy
Respiratory abnormalities: Chest pain that affects breathing, restrictive disease, upper lobe fibrosis
Jaw inflammation
Cauda equina syndrome (rare)
Patients with AS may also have psoriasis and/or inflammatory bowel disease

Extra-articular manifestations

Treatment

Medications: Relieve pain and reduce inflammation
- Non-steroidal anti-inflammatory drugs (NSAIDs): Ibuprofen and naproxen
- Corticosteroids: i.v. methylprednisolone
- Disease-modifying anti-rheumatic drugs (DMARDs): Sulfasalazine
- TNF-α inhibitors: Infliximab, adalimumab, and etanercept
Exercise: To reduce pain and stiffness
Physical therapy: Improve comfort and spinal flexibility
Surgery (rare): Repair significantly damaged joints or correct severe bends in the spine

Management

$ankylosing spondylitis, preoperative, intraoperative, postoperative, management, extra-articular, range of motion, airway, echocardiography, lung function test, imaging, arterial blood gas, ECG, awake fiberoptic intubation, larngyeal mask, intubation, positioning, neck, fractures, neuraxial anesthesia, epidural, paramedian$

Obstetrical anesthesia

Complicated due to difficult airway and difficult neuraxial techniques → have multiple plans in place
Consider paramedian approach and ultrasound guidance for neuraxial anesthesia

Keep in mind

AS is a challenge for the anesthesiologist because the rigid, immobile, fragile spine makes intubation, general anesthesia, and neuraxial anesthesia difficult
Awake fiberoptic intubation is the safest method of securing the airway in AS patients, but supraglottic airway devices such as laryngeal masks can also be used
The use of alternative approaches, such as the paramedian approach or the use of ultrasound guidance, may improve success with neuraxial anesthesia in AS patients