Prolonged duration of spinal anesthesia with normal dose of hyperbaric bupivacaine: case report

Abstract

Background: Spinal anesthesia has been used for over 120 years as a relatively safe and effective method technique. A well-known anesthetic, bupivacaine is the most widely used local anesthetic in the subarachnoid space. We report a case of prolonged sensory and motor blockade in a patient undergoing spinal anesthesia with 15 mg of 0.5% hyperbaric bupivacaine without any adjuvant, which lasted 32 hours to regress. Case Report: The patient was a 36‑year‑old female, obese, with no known comorbidities, who was undergoing surgical treatment of varicose veins of the lower limbs. Normal pre-operative exams. After sedation with midazolam 2.5 mg, the patient was in a sitting position and 3 attempts at subarachnoid puncture with a 27G cutting needle were unsuccessful. Another attempt with a 25G cutting tip needle was successful and injected 15 mg of 0.5% hyperbaric bupivacaine without adjuvants. The surgical procedure lasted 3 hours without cardio circulatory changes, and the patient was referred to PACU. Ten hours after the persistence of sensory and motor blocks. MRI of the thoracolumbar spine was performed without evidence of alteration. After 17 hours, both sensory and motor blocks remained, requiring bladder catheterization. After 23 hours, the neurological examination was normal, showing the permanence of both blocks. The complete return of sensory and motor blocks occurred after 32 hours, with hospital discharge in 4 hours, after complete regression of the subarachnoid block. Conclusions: In conclusion, an unexpectedly prolonged spinal block can be seen with regular doses of 0.5% hyperbaric bupivacaine. We cannot determine the exact etiology in our present case, with a normal MRI thoracolumbar.