Bilateral Low-Frequency Air-Bone Gap Following Spinal Anesthesia: An Unusual Audiometric Presentation: Case Report

Background and Clinical Significance: To report an unusual case of a bilateral low-frequency air-bone gap consistent with an apparent conductive audiometric pattern following spinal anesthesia and discuss a possible underlying mechanism; Case Presentation: A 56-year-old man underwent elective inguinal hernia repair under spinal anesthesia. On the second postoperative day, he developed a severe postural headache followed by bilateral hearing loss. Otoscopic examination was normal. Tuning fork tests and pure-tone audiometry demonstrated a bilateral low-frequency air-bone gap consistent with an apparent conductive audiometric pattern. Laboratory findings were unremarkable. The patient was managed conservatively with bed rest, hydration and systemic corticosteroids, resulting in gradual clinical improvement; Conclusions: Hearing loss after spinal anesthesia is typically sensorineural and attributed to cerebrospinal fluid pressure alterations. This case highlights a rare apparent conductive audiometric pattern in the absence of clinically evident middle-ear pathology. A possible mechanism may involve altered inner-ear pressure dynamics leading to transient mechanical restriction of stapes mobility. Awareness of this atypical presentation may facilitate prompt recognition and appropriate management.