Open Access 20-03-2024 | Tracheostomy | Brief Communication
Effect of a Speaking Valve on Nasal Airflow During Tracheostomy Weaning: A Case Series
Published in: Neurocritical Care
Login to get accessExcerpt
In the intensive care unit (ICU), many patients with acquired brain injury (ABI) benefit from tracheostomy [1]. Tracheostomy weaning protocols typically include cuff deflation and tube capping [2‐4]. However, the roles and importance of these steps are debated. The rationale behind tube capping is to recreate airflow through the upper airway that promotes laryngeal reafferentiation, natural heating, air filtration, humidification through the nose, swallowing, and improved subglottic pressure [5, 6] (Fig. 1). However, tube capping can increase the respiratory workload by reducing the tracheal lumen diameter because it forces the airflow around the cannula [7] (Fig. 1, step 2 and b). Therefore, this may be considered risky or too demanding [7]. Cuff deflation without tube capping is sometimes suggested instead of cuff deflation with tube capping [8], but it has not been proven that this sufficiently recreates the upper airway airflow necessary for tracheostomy weaning.
Fig. 1
Upper panel: Tracheostomy with an inflated cuff. Airflow is possible only through the cannula (solid lines). Step 0, Airflow with a deflated cuff alone; solid lines: principal airflow routes (inspiratory and expiratory airflows through the cannula). Step 2, Airflow with a deflated cuff and a speaking valve; solid lines: the principal airflow routes (inspiratory airflow through the cannula, expiratory airflow through the nose); dashed lines: accessory airflow route (inspiratory airflow through the nose). Intermediate panel: An enlarged view of a tracheostomy tube inserted in the trachea. a The function of a speaking valve during inspiration; solid line, inspiratory airflow opens the valve and the air then goes through the cannula; dashed line, accessory inspiratory airflow through the upper airway. b The function of a speaking valve during expiration; expiratory airflow closes the valve and the air is then forced to pass through the upper airway. Lower panel: Example polygraph traces (patient 10): upper graph, nasal airflow; intermediate graph, respiratory inductance plethysmographic flow (RIP), and thus the reconstituted respiratory flow is based on the thoracic and abdominal movements; lower graph, the thoracic and abdominal movements. Step 0, Recording with a deflated cuff alone. Step 2, Recording with a deflated cuff and a speaking valve. Analyses employed clean 5-min samples at step 0, at the beginning of step 2, and 1 h thereafter if the patient remained in step 2 (black boxes). Vertical orange line, time of speaking valve placement. ant, anterior, RL, recording length (90 min), sup, superior
× ![]()
…