What are the challenges and considerations for regional anesthesia in patients with rheumatoid arthritis due to altered landmarks?

Regional Anesthesia in Rheumatoid Arthritis: Altered Landmarks and Technical Considerations

Critical Airway and Anatomical Challenges

Advanced rheumatoid arthritis is explicitly recognized as a risk factor for difficult airway management, requiring mandatory pre-procedural airway assessment before any sedation or anesthesia. 1

Specific Anatomical Alterations in RA

• Cervical spine involvement creates altered landmarks for neuraxial anesthesia, with atlantoaxial instability and reduced neck mobility complicating both airway management and spinal/epidural placement 2, 3
• Temporomandibular joint disease limits mouth opening, affecting airway visualization and potentially complicating mask ventilation 2, 4
• Cricoarytenoid arthritis can cause stridor, airway obstruction, and unpredictable airway anatomy, making both general and regional anesthesia more complex 2, 3
• Spinal deformities and previous back surgery alter surface landmarks for neuraxial blocks, with documented cases of epidural failure attributed specifically to ankylosing spondylitis-related anatomical changes 1

Pre-Procedural Evaluation Requirements

Every RA patient must undergo systematic airway and spinal assessment before regional anesthesia, regardless of the planned technique. 1, 3

Mandatory Assessment Components

• History of previous anesthesia problems including failed intubations or difficult regional blocks 1
• Cervical spine imaging review when available, particularly for neuraxial techniques, as cervical involvement may predict thoracolumbar disease 3
• Joint mobility assessment including neck flexion/extension, mouth opening, and ability to position for neuraxial blocks 2, 4
• Systemic manifestations affecting cardiovascular, respiratory, and renal systems that may influence anesthetic choice 2, 3

Technical Modifications for Regional Anesthesia

Ultrasound-Guided Techniques Are Preferred

Ultrasound guidance should be used for all regional blocks in RA patients to compensate for altered surface landmarks and visualize anatomical distortions in real-time. 1

• In-plane needling along the visual axis improves accuracy when landmarks are distorted, with the ultrasound machine positioned directly in front of the operator 1
• Real-time visualization of local anesthetic spread is more reliable than landmark-based techniques when anatomy is altered 5
• Dominant-hand needling is recommended for practitioners with limited experience in RA patients, as anatomical variations increase technical difficulty 1

Neuraxial Anesthesia Considerations

• Combined spinal-epidural technique may be preferred over single-shot spinal when anatomical landmarks are uncertain, allowing dose titration and catheter "top-up" capability 1
• Small-dose spinal initiation through CSE reduces risk of high block when vertebral anatomy is distorted 1
• Sitting position may be necessary for neuraxial placement despite positioning challenges, as lateral positioning may further obscure landmarks 3
• Multiple attempts should be anticipated, with documented cases requiring continuous spinal analgesia via epidural catheter placement when standard epidural failed 1

Peripheral Nerve Block Advantages

Peripheral nerve blocks are often superior to neuraxial techniques in RA patients because they avoid spinal deformities and positioning difficulties entirely. 3, 6

• Ultrasound-guided peripheral blocks bypass altered spinal landmarks and allow direct nerve visualization despite joint deformities 1
• Upper extremity blocks (interscalene, supraclavicular, axillary) are particularly useful for hand/wrist procedures common in RA, with successful arthroscopic synovectomy reported under regional anesthesia 7
• Lower extremity blocks avoid cervical spine manipulation required for airway management and spinal positioning 3

Critical Safety Considerations

Positioning and Ergonomics

• Table height adjustment is essential when patients cannot achieve standard positioning due to joint contractures, with optimal height 5 cm above to 10 cm below the operator's elbow 1
• Patient positioning limitations must be identified pre-procedurally, as inability to flex the spine may preclude neuraxial techniques entirely 1, 3
• Prolonged positioning should be avoided due to increased risk of pressure injuries and joint pain in RA patients 4, 3

Medication Interactions

• Immunomodulating drugs including biologics and DMARDs require consideration for infection risk, though regional anesthesia itself is not contraindicated 2, 3
• Chronic corticosteroid use may affect wound healing and infection risk but does not preclude regional techniques 3
• Anticoagulation assessment is mandatory before neuraxial techniques, as RA patients may be on antiplatelet therapy for cardiovascular disease 6

Multidisciplinary Communication

Effective communication among anesthesiologist, surgeon, and rheumatologist is essential before proceeding with regional anesthesia in RA patients. 4, 3

• Disease activity status should be confirmed, as active inflammation may affect positioning tolerance and complication risk 3
• Surgical positioning requirements must be discussed pre-operatively, as some positions may be impossible due to joint contractures 4
• Backup plans including conversion to general anesthesia must be established before starting, given higher failure rates with altered anatomy 1, 3

Common Pitfalls to Avoid

• Assuming normal anatomy based on external appearance—internal distortion may be severe despite minimal external deformity 3
• Proceeding without ultrasound when available—landmark techniques have unacceptably high failure rates in RA 1
• Inadequate airway preparation even for regional-only cases—emergency airway management may be required and will be difficult 1, 2
• Single-technique planning without alternatives—have multiple backup plans given higher technical failure rates 1, 3