Chilean scientists demonstrate the effectiveness of a maneuver to rehabilitate the sense of smell in laryngectomized patients.

Total laryngectomy is a surgical procedure in which the entire larynx is removed, primarily performed in patients with larynx cancer. It is a highly disabling condition, as it alters all the functions of the larynx, with the loss of voice the most evident consequence after the operation.

However, when air through the upper airways is interrupted, another equally important and not adequately studied sequela is the partial or complete loss of smell (anosmia and hyposmia, respectively).

Faced with this situation, a group of academics from the Universidad Andrés Bello, the Universidad de Chile, and the Barros Luco Trudeau Hospital addressed the need for comprehensive rehabilitation, covering all the functions that are lost after this procedure.

The authors of the study pointed out that when analyzing the current literature, they found many studies focused on voice rehabilitation, but only a limited number of studies addressed olfactory rehabilitation in laryngectomized patients. Moreover, «in Chile, there is no experience in this regard,» they emphasize.

«The loss of smell is associated with alterations in the sense of taste and exposes the patient to risk situations, being unable to detect the smell of smoke, a gas leak or bad food, as well as creating insecurity and greater frustration by not being able to perceive body odor in social situations,» concludes the study.

Recovering smell and taste

The research demonstrated that the technique called «nasal airflow induction maneuver» (MIFAN), also known as the «educated yawning technique,» rehabilitates olfactory ability in patients who have undergone total laryngectomy for laryngeal cancer.

The maneuver consists of yawning with the mouth closed. By doing this, air enters through the nose, and the sense of smell can be progressively restored.

Sebastián Sánchez, the co-author of the study and an academic of the School of Speech Therapy at UNAB, points out that demonstrating the effectiveness of this maneuver «opens up the possibility of providing a better quality of life to these users since it addresses little-known aspects of the sequelae of this procedure.»

«In the past (loss of smell) was not something that was considered, purely because it was not something of a vital risk; however, by working from the perspective of improving the quality of life, we are covering more and more needs, which despite not being urgent, are of great importance in the daily lives of our users,» said Sanchez.

The academic points out that another critical factor reported by patients was the emotional point of view. The loss of smell prevented the evocation of memories associated with different aromas or their relationships.

For the research, the academics based their work on European experiences, where it was determined that the strategy was simple to apply and allowed generating an airflow through the nasal cavity, «the basic principles of this technique are very similar to rehabilitation strategies used by phonoaudiologists in other areas of the discipline, such as voice and swallowing,» said Sanchez.

The quasi-experimental study was conducted on twelve patients laryngectomized for laryngeal cancer at the Otorhinolaryngology Department of the Hospital Barros Luco Trudeau (HBLT) in Santiago, Chile.

When olfaction was evaluated with an olfactometric test before and after rehabilitation with the maneuver, it was observed that before the process, two-thirds of the sample presented total loss of olfaction and one-third partial loss; In contrast, after rehabilitation, all the patients showed olfaction, marking a statistically significant difference.

Finally, Sebastián Sánchez says this technique «will allow us as speech therapists to open up a new field of action and specialization to provide a comprehensive service following the needs of our users.»

Written by Qué Pasa