{'fraction_non_alphanumeric': 0.03586597451628126, 'fraction_numerical': 0.030202925908447382, 'mean_word_length': 5.5030674846625764, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Neuraxial Anesthesia and Analgesia in Patients with Preexisting Central Nervous System Disorders

Historically, the use of regional anesthetic techniques in patients with preexisting central nervous system (CNS) disorders has been considered relatively contraindicated. The fear of worsening neurologic outcome secondary to mechanical trauma, local anesthetic toxicity, or neural ischemia is commonly reported. We examined the frequency of new or progressive neurologic complications in patients with preexisting CNS disorders who subsequently underwent neuraxial blockade. The medical records of all patients at the Mayo Clinic from the period 1988 to 2000 with a history of a CNS disorder who subsequently received neuraxial anesthesia or analgesia were retrospectively reviewed. One-hundred-thirty-nine (n = 139) patients were identified for study inclusion. Mean patient age was 60 ± 17 yr. Gender distribution was 86 (62%) males and 53 (38%) females. An established CNS disorder diagnosis was present a mean of 23 ± 23 yr at the time of surgical anesthesia, with 74 (53%) patients reporting active neurologic symptoms. Spinal anesthesia was performed in 75 (54%) patients, epidural anesthesia or analgesia in 58 (42%) patients, continuous spinal anesthesia in 4 (3%) patients, and a combined spinal-epidural technique in 2 (1%) patients. Bupivacaine was the local anesthetic most commonly used in all techniques. Epinephrine was added to the injectate in 72 (52%) patients. There were 15 (11%) technical complications, with the unintentional elicitation of a paresthesia and traumatic needle placement occurring most frequently. A satisfactory block was reported in 136 (98%) patients. No new or worsening postoperative neurologic deficits occurred when compared to preoperative findings (0.0%; 95% confidence interval, 0.0%–0.3%). We conclude that the risks commonly associated with neuraxial anesthesia and analgesia in patients with preexisting CNS disorders may not be as frequent as once thought and that neuraxial blockade should not be considered an absolute contraindication within this patient population.