SPECIFIC PROBLEMS OF THE ORTHOPEDIC PATIENT
Rheumatoid Arthritis
Rheumatoid arthritis is a disease of unknown origin characterized
by immune-mediated synovitis.[1]
The patients who
present the most significant challenge to the anesthesiologist are those with advanced
disease having deformity, instability, and destruction of many joints throughout
the body. The cervical spine, hips, shoulders, knees, elbows, ankles, wrists, and
metacarpophalangeal joints may all be affected.[1]
Although cardiac valvular lesions, pericarditis, and pulmonary interstitial fibrosis
do occur, these secondary features of the disease are usually not clinically significant.
However, there is an increased incidence of ischemic heart disease (presumably from
corticosteroid treatment), cancer (from chemotherapeutic drugs), and infections,
all of which contribute to only a 50% 5-year survival rate for advanced cases.[2]
These patients also have an impaired immune system, wasted musculature, and underlying
hypermetabolism. All these factors contribute to an increased rate of postoperative
infections and other complications.[3]
The anesthesiologist's immediate concerns, however, tend to be
technical. Arterial lines may be difficult to place because of small calcific radial
arteries that may be inaccessible due to flexion deformities of the wrist joint.
These patients have a high incidence of carpal tunnel syndrome, which may predispose
them to recurrent symptoms postoperatively if radial artery lines are inserted.[4]
Central venous lines may be difficult to insert because of fusion and flexion of
the neck. The lumbar spine, however, is often not affected in rheumatoid arthritis,
and spinal anesthesia and epidural anesthesia are usually straightforward.[5]
Other technical problems of concern are airway management and
cervical spine instability.[6]
[7]
The trachea may be difficult to intubate for a number of reasons ( Table
61-1
) that are most prominent in those with juvenile rheumatoid arthritis.
Atlantoaxial instability ( Table 61-2
)
develops in many patients with adult onset of rheumatoid arthritis.[8]
[9]
[10]
[11]
Symptoms include neck pain, headache, or neurologic symptoms in the arms or legs
with neck motion.[10]
Atlantoaxial subluxation
develops from erosion of ligaments by rheumatoid involvement of the bursae around
the odontoid process of C2 ( Fig. 61-1
).
Acute subluxation may result in cord compression or compression of the vertebral
arteries with quadriparesis or sudden death. Subluxation occurs with flexion of
the neck ( Fig. 61-2
). Anesthetic
management must prevent flexion of the neck and maintain stability of the cervical
spine. This may be accomplished by tracheal intubation
TABLE 61-1 -- Orthopedic patients in whom intubation of the trachea may be difficult
|
Diagnosis |
Causes of Difficulty |
|
Ankylosing spondylitis |
Fusion of cervical spine |
|
Juvenile rheumatoid arthritis |
Ankylosis of cervical spine |
|
Hypoplasia of mandible |
|
Adult rheumatoid arthritis |
Multiple deformity |
|
Ankylosis and instability of the cervical spine |
|
Prior spinal fusion |
Ankylosis and limited extension of the cervical spine |
|
Congenital deformities of the cervical spine |
|
|
Epiphyseal dysplasia |
|
|
Dwarfism (achondroplasia)[276]
|
|
|
Fractured cervical spine[277]
|
Limited motion |
|
Risk of quadriplegia |
*Patients
are stable in extension, but flexion may compress the spinal cord or medulla oblongata.
using a flexible bronchoscope under topical anesthesia and positioning the patient
while the patient is still awake. Regional anesthesia with the patient minimally
sedated and the neck stabilized is a reasonable perioperative alternative.
Patients with severe rheumatoid arthritis may develop airway obstruction
postoperatively from narcotics or sedatives.[12]
Judicious use of narcotics or epidural analgesia for pain relief should be considered
postoperatively, together with the administration of nasal oxygen and pulse oximetry
if feasible. Cardiopulmonary resuscitation is difficult in rheumatoid patients (see
Chapter 27
), and emergency
tracheotomy is almost impossible in severe cases (see Chapter
42
). Jet ventilation by means of a percutaneous catheter through the cricothyroid
membrane may be required.[13]
Figure 61-1
Magnetic resonance image of a patient with advanced rheumatoid
arthritis demonstrates invagination of the odontoid process of C2 (arrow)
through the foramen magnum, compressing the brainstem. Notice the degeneration of
C4 and C5, a common problem in rheumatoid arthritis.
Figure 61-2
Computed tomographic scan of the neck demonstrates moderate
subluxation of C1 and C2. The odontoid (single arrow)
tends to compress the spinal cord (double arrow)
against the posterior arch of C1, especially during neck flexion.
