Effect of a passive exhalation port on tracheostomy ventilation in amyotrophic lateral sclerosis patients: a...

Amyotrophic lateral sclerosis (ALS) patients often require long-term tracheostomy ventilation (LT-TV) because of progressive ventilatory failure. Although widely used for non-invasive ventilation (NIV), passive exhalation port systems have not been gaining popularity for TV because of the possibility of carbon dioxide (CO₂) rebreathing. The current study set out to investigate the effect of a Whisper Swivel connector in comparison to an active exhalation valve on gas exchange and symptoms in ALS patients requiring LT-TV.

A prospective randomized controlled trial was carried out to compare the clinical outcome of ten ALS patients receiving LT-TV by means of a Trilogy 100 ventilator with a Whisper Swivel passive exhalation port (group A) and of 10 ALS patients connected to an Airox Legendair ventilator with an active exhalation valve (group B). The study's main outcome measure was CO₂ retention at the 30-day follow-up assessment.

One patient in each of the two cohorts showed significant CO₂ retention. At the 30-day assessment, scores on the following measures were not significantly different in the two groups: the Borg dyspnea scale {2 [1-3] vs. 1 [1-3]; P=0.2891}, the visual analogue scale (VAS) dyspnea {20 [10-85] vs. 20 [0-50]; P=0.8571}, the Epworth sleepiness scale (ESS) {8 [4-10] vs. 5.5 [0-12]; P=0.1443}, the EuroQol-VAS (EQ-VAS) {55 [50-80] vs. 50 [30-80]; P=0.4593} and the relative stress scale (RSS) {49 [30-65] vs. 52 [25-64]; P=0.8650}. At the 3-month follow-up assessment, the numbers of hospitalizations and deaths were likewise similar in the two groups.

The efficacy of the Whisper Swivel connector is similar to that of an active exhalation valve in ALS patients undergoing LT-TV.