Spinal Anesthesia: Contraindications

Spinal anesthesia is generally used for procedures ~umbilicus (T10 dermatome) and below

Absolute contraindications (i.e. don’t even think about it)

• Patient refusal (patient’s right to decide; you can make recommendations for what you think is in patient’s best interest but avoid coercive attempts)
• Infection at/near site of needle insertion (risk: meningitis)
• Elevated intracranial pressure (risk: brain herniation when 1) CSF is lost through needle via uneven pressure differential in brain, or 2) after injection of anesthetic → ↑ fluid volume → ↑ pressure)
• Bleeding diathesis/coagulopathies. Some (not all) examples include: anticoagulation not stopped within appropriate amount of time, hemophilias, von Willebrand disease, Vitamin K deficiency, DIC, liver disease, some malignancies such as leukemia (risk: epidural hematoma → spinal cord compression)
• Hypovolemia (risk: hypotension)
• Indeterminate neurologic disease (risk: could exacerbate “the” disease, potential local anesthetic toxicity if nerves demyelinated)

Relative contraindications (i.e. weigh risk vs. benefit and then decide on a case-by-case basis)

• Bacteremia (if decide to perform spinal then consider the administration of prophylactic antibiotics prior to puncture)
• Spinal stenosis (risk: difficult placement and/or potential nerve injury)
• Pre-existing neurological disease (i.e. MS – this is controversial; risk: potentially ↑ risk of local anesthetic toxicity due to demyelinated nerves. However, if not currently experiencing a flair then it is likely ok; and having a pain-free surgery may actually help to prevent a pain/stress-induced flair)
• Unknown duration of surgery (risk: spinal anesthetic may not last long enough)
• Abnormal lab values, particularly low platelets or elevated INR (risk: bleeding → epidural hematoma → spinal cord compression). There is no consensus on cutoff values for platelets or INR, everyone has their own criteria; though ranges are generally 70-90,000 for platelets, and 1.3-1.4 for INR).
• Aortic stenosis (risk: hypotension/↓ MAP → ↓ coronary perfusion → myocardial ischemia)
• Vertebral column deformities/previous lumbar surgery (i.e. fusion, hardware) (risk: abnormal anatomy → difficult placement and/or potential injury to nerves or other structures)
• Surgery requiring sensory level higher than T10 (risk: “high spinal” → sympathectomy → cardiovascular collapse particularly if patient has cardiac disease; also could block diaphragm + intercostal muscles → respiratory distress/apnea)