Cough suppression techniques may be useful adjuncts that can significantly reduce the chance of aerosol contamination within at-risk medical professionals' groups.

Recently published data suggest tracheal intubation is not a significant generator of aerosolized particles. While undoubtedly requiring further study and expansion into different, perhaps less-controlled environments (study conditions included “Ultraclean” laminar flow operating theatres), it seems that extubation produced a 15-fold increase in detectable aerosols, especially when the patient coughed.

Multiple methods to achieve cough reduction have already been described in the form of laryngotracheal anaesthesia through a modified endotracheal tube and use of remifentanil augmentation. These methods have yielded up to 75% cough suppression. A further study comparing the use of laryngotracheal lidocaine (4 ml, 4% concentration) showed a reduction in the incidence of coughing before (66% to 26%) and after extubation (30% vs 4%) in procedures lasting less than 2 hours.

While administering laryngotracheal anaesthesia via a standard laryngotracheal anaesthesia kit represents a further instrumentation of the airway and the use of more equipment and thus further risk, in the era of the video-laryngoscope this becomes a very simple technique.

Implementing such strategies in Covid positive/suspect patients may, alongside eliminating its proven negative side effects such as hypertension, tachycardia, arrythmias, and increases in intracranial and intraocular pressure, help reduce aerosol spread and subsequently reduce the contamination risk of medical staff.

We provide an overview of evidence-based cough suppression techniques which may provide an additional layer of protection to those managing the airway in the Covid era.

 

Keywords- Airway; Intubation; Aerosol; Laryngotracheal anaesthesia; Remifentanil; Cough suppression