Abnormal motor blockade after epidural analgesia caused by pneumorrhachis and the role of hyperbaric oxygen treatment: a case report

Introduction: Pneumorrhachis is a rare clinical entity that is usually asymptomatic. Previous reports have associated such events with epidural insertion using a loss of resistance (LOR) to air technique. This report describes a case of symptomatic epidural pneumorrhachis following epidural anaesthesia using LOR to saline. Case report: A 32-year-old American Society of Anesthesiologists (ASA) Classification II female patient was admitted for unplanned caesarean section. Epidural anaesthesia was performed at the L3-4 space using LOR to saline. The procedure, including delivery of the neonate, was uneventful. In the recovery room, a local anaesthetic infusion via an elastomeric pump (infusion 'balloon') was started. Two hours after initiation of the infusion the patient complained of motor blockade, so it was stopped. Two hours later she remained paraparetic, and a neurologist assessment was required. A computed tomography scan showed epidural pneumorrhachis at the L2-3 level. The patient was referred for emergent hyperbaric oxygen treatment (US Navy Treatment Table 5) and following one session the patient recovered completely. Discussion: Anaesthetists should be aware of this rare complication, which is easily overlooked. Hyperbaric oxygen treatment is a first line treatment for gas-associated lesions with neurological impairment. Timely referral is essential to prevent irreversible deficits.