Re: Investigating sudden hearing loss in adults
Remarkably, Fishman and Cullen do not mention Hyperbaric Oxygen Therapy in their paragraph on how adult patients with sudden hearing loss should be managed.1 This, whereas the Cochrane Systematic Review finds a significant positive effect for this treatment modality, which is more than can be written about steroids.
The Cochrane Review states that ‘in view of the modest number of patients, methodological shortcomings and poor reporting, this result should be interpreted cautiously’. However, this statement is not much worse than the one for steroids: ‘the value remains unclear since the evidence obtained from randomised controlled trials is contradictory in outcome, in part because the studies are based upon too small a number of patients’. It probably just reflects the fact that for rare conditions good trials are often scarce.
Furthermore, not withstanding the importance of good methodology, logic comes first. The inner ear is an organ with a relatively high oxygen demand and limited vascular supply. The etiology of sudden deafness, in many cases, has to do with acute oxygen shortage. So, like with a cardiac arrest or cerebral infarct, the most important factor is time. From literature it is clear that the sooner the therapy is started, the higher the hearing gain. Notice, that in studies patients were often included up to a week or 10 days. Thus, although better methodology will probably reach the same conclusion with a higher level of evidence, a quicker therapy start in studies will probably show an increased effect.
We use this treatment in the acute phase of acoustic trauma as well. Also for acute acoustic trauma the treatment effect is much better for those patients who start therapy within two days.
The only side effect we have seen so far - in our young and healthy military population – is temporary, minimal barotrauma to the middle ear and sinus. This outweighs the devastating effect of permanent
sensorineural hearing loss by far. (The cost of therapy is about 1500 euro, which equals a good hearing aid.)
The spontaneous complete recovery for sudden deafness is only 39% so additional therapy is definitely warranted.2
Therefore, in our opinion, Sudden Deafness is a real ENT emergency for which the possibility, and the pros and cons of HBO should be discussed in shared decision making. We certainly recommend it based on our personal experience.
1) Fishman JM, Cullen L. Investigating sudden hearing loss in adults. BMJ 2018;363:k4347. 10.1136/bmj.k4347
2) Bayoumy AB, van der Veen EL, de Ru JA. Assessment of spontaneous recovery rates in patients with idiopathic sudden sensorineural hearing loss. JAMA Otolaryngol Head Neck Surg. 2018;144(8):655-656.
Competing interests: No competing interests