Patient-ventilator asynchrony, leaks and sleep in patients with amyotrophic lateral sclerosis

Abstract

Sleeping with non-invasive ventilation (NIV) in amyotrophic lateral sclerosis appears to be accompanied by a high patient-ventilator asynchrony (PVA) index. This prospective observational cohort study quantifies PVA and leaks, and searches for effects of these events on sleep after polysomnographic NIV titration. Full-video polysomnography, with incorporation of transcutaneous carbon dioxide and ventilator software, was used to analyse sleep epoch-by-epoch and respiratory events and PVA breath-by-breath in 35 patients (17 non-bulbar). After diagnostic polysomnography, NIV was titrated during three consecutive nights. Sleep, PVA and leaks were evaluated at discharge and after one month. Results showed that non-bulbar patients improved in sleep architecture and oxygen and carbon dioxide levels while bulbar patients only improved oxygen saturation. PVA remained present at discharge (non-bulbar 54 (21-101) and bulbar 31 (9-39)/h sleep) and one month (non-bulbar 31 (9-39) and bulbar 32 (17-55)/h sleep), with ineffective effort as most prominent asynchrony. Leaks also persisted after titration (non-bulbar 16.6 (3.1-44.6) and bulbar 5.1 (0.0-19.5)% of total sleep time (TST)) and one month (non-bulbar 7.7 (1.4-29.3) and bulbar 12.7 (0.0-35.2)% TST). PVA and leaks have none to minor effect on sleep architecture. In conclusion, although PVA and leaks remain present after meticulous NIV titration, these events seem not to interfere with sleep.

And the Doctor Continues: “…But I Have to Choose My Gear Wisely”

“…7 Furthermore, Atkeson et al found a high number of episodes of patient-ventilator asynchrony (PVA) (mean ± SD, 69 ± 46 events/h) when NIV was applied in patients with ALS, 9 theoretically harming sleep architecture and sleep quality. In our study, by using in-hospital full-video polysomnography with incorporation of ventilator software during NIV titration, non-bulbar and bulbar patients showed a lower PVA-index of 31 (IQR 15-49) events/h sleep and 32 (IQR 17-55) events/h sleep, respectively, after one month of NIV, 10 and these remaining asynchronies had none to minor impact on sleep architecture. Ensuring good sleep architecture could enhance therapeutic compliance and thereby produce better improvements in quality of life.…”

“…Our most recent study, using the same titration procedure, showed that only 14% of the patients were positive on this cutoff value for airway obstruction. 10 These data suggest that polysomnographic titration facilitates the adjustment of NIV …”

Randomized cross‐over trial of ventilator modes during non‐invasive ventilation titration in amyotrophic lateral sclerosis

“…29 Our current and previous research show, respectively, 23% and 14% of the patients with >5 obstructive events per hour on ST mode. 19 These data suggest that polysomnographic titration probably facilitates the adjustments of NIV settings which could be of major importance on a rapid progressive disease as ALS.…”

“…18 Furthermore, it has been shown that PVA remained present even after meticulous polysomnographic NIV titration, nevertheless, without sleep interference. 19 The aim of this randomized cross-over trial was to provide more insight into the NIV titration procedure in patients with ALS. Comparisons in gas exchange, sleep architecture and PVA were made between two different NIV modes: the S mode and ST mode.…”

“…found severe asynchrony in 79% of their patients of which ineffective effort was the most prominent . Furthermore, it has been shown that PVA remained present even after meticulous polysomnographic NIV titration, nevertheless, without sleep interference …”