Treatment of sudden sensorineural hearing loss with a continuous epidural block

Hearing Loss after Spinal Anesthesia: The Effect of Different Infusion Solutions

OBJECTIVE: We speculate that the preoperative volume replacement with a convenient solution may protect the inner ear function after spinal anesthesia.

METHODS: The patients were randomized in a single-blind fashion into two groups: group LR (n = 40) received lactated Ringer's and group GF (n = 40) received gelatin polysuccinate 4% (Gelofusine). Spinal anesthesia was performed with a 25 G Quincke needle and was given bupivacaine 0.5% 10 mg and fentanyl 25 jxg. Audio-grams were performed preoperatively and 2 days postoperatively.

RESULTS: The overall incidence of hearing loss was 7.5%. The hearing loss was unilateral in two and bilateral in four patients. Hearing loss occurred within the low-frequency range and the hearing thresholds returned to normal by the fifth postoperative day.

CONCLUSIONS: Although the incidence of hearing loss for the lactated Ringer's group was higher than the Gelofusine group, there was no statistically significant difference between the groups. For medicolegal and ethical reasons, patients should be informed about the possibility of hearing loss after spinal anesthesia.

Experimental otoacoustic emission and auditory brainstem response changes by stellate ganglion blockage in rat

INTRODUCTION

To investigate the effect of stellate ganglion (SG) block on hearing in rats.

MATERIALS AND METHODS

Sixteen male adult rats were randomly divided into 2 equal groups. Both groups underwent preblock auditory brainstem responses (ABRs) in response to tone bursts at 4, 6, and 8 kHz and otoacoustic emissions in response to distortion products as a function of f2 frequency at 1, 2, 4, and 6 kHz. Local anesthetic (0.2 mL of 2% prilokain) was administered to the left SG of the study group by posterior cervical percutaneous approach for cervical sympathetic blockage. In the control group, 0.2 mL of physiological saline was injected to the left SG. Postblock hearing evaluations were made after 15 minutes of injections.

RESULTS

Both Dp-gram and I/O function records suggested that whereas hearing thresholds were not affected in lower frequencies after SG blockage, it tended to increase at higher frequencies. In ABR records, waves I and II showed marked latency shift across all frequencies. The interpeak latency of waves I and II was shortened after blockage. Saline injection did not show any significant ABR or distortion-product otoacoustic emission threshold shift across frequencies at 60, 70, 80, and 90 dB sound pressure level.

CONCLUSION

Our data demonstrate that SG block improved the hearing parameters in rats with normal cochlear blood flow. To recommend SG blockage as a treatment option in the vascular pathologies of cochlea, further investigation should assess the efficiency of ganglion blockage in hearing parameters of rats with impaired cochlear blood flow.

Postoperative sudden sensorineural hearing loss after posterior lumbar decompression: a case report

PURPOSE

We report a case in which a patient sustained a dural tear during spinal surgery under general anesthesia complicated by a severe and persistent unilateral sensorineural hearing loss.

CLINICAL FINDINGS

A 51-yr-old man with no previous otological history underwent a posterior lumbar decompression surgery in the prone position under general anesthesia. A small dural tear was discovered intra-operatively and was repaired by sutures. Surgery lasted for eight hours with over 3 L of blood loss. Recovery from anesthesia was otherwise uneventful. A unilateral right-sided sensorineural hearing loss was discovered shortly after completion of surgery. This was associated with mild tinnitus but no vertigo. There was no aural fullness, pain, headache or postural element to his symptoms. Despite extensive investigations, treatment and follow-up by an otorhinolaryngologist, his symptoms failed to improve 18 months following surgery.

DISCUSSION

The possible etiologies, preventive strategies, prognosis and management plan of this rare complication are discussed.

Transient locked-in syndrome resulting from stellate ganglion block in the treatment of patients with sudden hearing loss

Stellate ganglion blockage (SGB) is a local anesthetic procedure intended to block the lower cervical and upper thoracic sympathetic chain and is one of the treatment modalities for a wide range of disorders such as sudden hearing loss, Menier's disease, stroke, sudden blindness, shoulder/hand syndrome and vascular headache. The complications of SGB are recurrent laryngeal or phrenic nerve block, pneumothorax, unconsciousness, respiratory paralysis, convulsions and sometimes severe arterial hypotension. We present a case with transient locked-in syndrome following SGB for the management of sudden hearing loss. The risk of an intra-arterial injection can be eliminated by rotating the needle, as is described in this report.