Unintentional neuromuscular blocking agent injection during an axillary brachial plexus nerve block

OBJECTIVE: We describe the consequences of an unintentional injection of atracurium instead of ropivacaine during an axillary brachial plexus nerve block. CASE REPORT: A 79-year-old woman was scheduled for wrist fracture repair. An axillary brachial plexus block was performed by use of a nerve stimulator. Twenty milliliters of 0.5% ropivacaine with 1:200,000 epinephrine was injected on the radial and then on the median nerves. Two minutes later, the patient became dyspneic and was unable to elevate her head from the pillow. A check of the syringes revealed that one contained 50 mg of atracurium instead of 0.5% ropivacaine. After IV propofol was administered, the trachea was intubated and controlled ventilation started. At the end of surgery (more than 2 hours later), reversal of residual neuromuscular block was performed. The motor and sensory brachial plexus block completely recovered 12 hours after the initial bolus injection. No clinical neurological deficit was reported afterward by the patient. CONCLUSIONS: Unintentional injection of atracurium mixed with ropivacaine during axillary brachial plexus block leads to complete body paralysis that requires general anesthesia and mechanical ventilation. Recovery was complete without any neurological sequela. An analysis of the chain of events that led to the error suggests some recommendations to improve our daily practice.