[Carbogen combined with drugs in the treatment of sudden deafness]. [Randomized double-blind study of therapy of sudden deafness. Low molecular weight dextran + naftidrofuryl vs. low molecular weight dextran + placebo]. Effect of prostaglandin E1 on idiopathic sudden sensorineural hearing loss: a double-blinded clinical study.
To analyze the clinical efficiency and study the possible mechanism of the carbogen combined with drugs in the treatment of sudden deafness.
                Fifty-two patients with sudden deafness were divided into two groups: Twenty-six cases received carbogen (5% CO2 - 95% O2) combined with drug therapeutics of a course of intravenous administration of dexamethasone, vitaminB, low molecular dextran, salviae miltiorrhizae, and intake vitaminC, vitaminE, et al and the other 26 cases received the drugs only. The clinical effects were compared.
                The total effective rate was 76.92% in the carbogen group and 50.00% in the control group. The difference was significant between the two groups. The recovery time in the carbogen group was 3-14 days while in the control group was 6-23 days.
                The efficiency of carbogen ombined with drugs is superior to drug therapeutics in the treatment of sudden deafness. Eighty patients with idiopathic sudden deafness existing no longer than 10 days were included in a prospective randomized double-blind study. Patients were treated for 10 days with infusions of either 10% low-molecular weight dextran or the combination of low-molecular weight dextran with naftidrofuryl. Before treatment and after 10 days hearing loss in the affected ear was determined at 0.5, 1, 2, 3, 4 and 6 kHz. The mean hearing loss was then calculated as the average from these values. During monotherapy with low-molecular weight dextran the mean hearing loss decreased from 40 to 27 dB compared to 38 to 17 dB when naftidrofuryl treatment was added (p < 0.01 between groups). A significant benefit of naftidrofuryl on hearing loss was also found at frequencies between 0.5 and 3 kHz. Furthermore, patients reported better improvement of tinnitus when naftidrofuryl was combined with dextran. Two patients receiving dextran alone developed side effects: one had an allergic reaction causing withdrawal of treatment, which the other case had vertigo, nausea and headache with spontaneous recovery. The results of the study showed that treatment with naftidrofuryl in addition to hemodilution with low-molecular weight dextran was of therapeutic benefit in the therapy of sudden deafness without increasing the rate of side effects. The authors conducted a prospective, randomized, double-blinded clinical trial for the purpose of elucidating the effects of prostaglandin E1 (PGE1) on idiopathic sudden sensorineural hearing loss.
                With the approval of the institute ethics committee, a total of 57 consecutive patients with diagnoses of idiopathic sudden sensorineural hearing loss were included in the study. The patients in the PGE1 group received continuous infusion containing 60 microg PGE1 and 100 mg hydrocortisone for 7 days, and the patients in the placebo group were treated with continuous infusion containing an inactive placebo and 100 mg hydrocortisone.
                No significant differences were observed in the improvements of pure-tone average and subjective symptoms between the PGE1 and the placebo groups. However, the hearing improvement at high frequencies (4 kHz and 8 kHz) was significantly higher in the PGE1 group than in the placebo group, especially in the patients with severe tinnitus.
                These results failed to prove a beneficial effect of PGE1 in the treatment of idiopathic sudden sensorineural hearing loss. Further studies will be needed to clarify the pharmacologic actions of PGE1 in the cochlea.