Ambulatory adaptation of non-invasive ventilation in Motor Neuron Disease: where limits of effectiveness end

Abstract

with earlier onset ventilation; however, we feel these data raise waiting time as a potential issue for consideration. We also concur with Lujan and Esquinas regarding indication criteria; at the time of our study decisions to trial ventilation were based on the thenaccepted criteria of FVC less than 50% predicted, orthopnoea and hypercapnia (5). Controlled studies of the effect of NIV implementation earlier in the disease, and studies that account for phenotypic variability in MND, would assist with addressing this important clinical question.We would agree that it is diffi cult to attribute late mortality to the model of care of initial NIV implementation. Our study was not designed to assess mortality, with survival being a secondary, explorative outcome. We did not record adherence to NIV, bulbar function and other factors the authors correctly raise as being important. However, we believe that, despite the limitations of our study, it suggests waiting time affects important clinical outcomes. If the local healthcare system structure and expertise can support it, an ambulatory model with comprehensive follow-up offers fl exible and timely access to NIV in MND. Declaration of interest:The authors report no confl icts of interest. The authors alone are responsible for the content and writing of the paper. ReferencesSheers N , Berlowitz DJ , Rautela L , Batchelder I , 1.Hopkinson K , Howard ME . Improved survival with an ambulatory model of non-invasive ventilation implementation in motor neuron disease . Amyotroph Lateral Scler Frontotemporal Degener. 2014 ; 15 : 180 -4 . Dear Editor,We thank M. Lujan and A. M. Esquinas for their considered letter regarding the use of ambulatory models for implementing non-invasive ventilation (NIV) in motor neuron disease (MND). As they state, the small cohort study we performed (1) is the fi rst to examine an ambulatory model in people with MND specifi cally. Previous studies by Lujan et al. (2) and Chatwin et al. (3) evaluated the effect of an ambulatory model of NIV implementation in heterogenous diseases, with the one participant with MND in both studies allocated to the traditional model of care group. The recently published randomized controlled trial by Pallero et al. included participants with ' slowly progressive neuromuscular disease ' and demonstrated similar therapeutic effect regardless of model of implementation.With regard to the survival advantage found in our study, we agree with Lujan and Esquinas that this is most apparent in the early period. Patients in the traditional inpatient model of care group had a longer waiting period from decision to trial NIV to implementation of NIV. Although baseline PaCO 2 at time of implementation would suggest as a group that they were not more acutely unwell than the ambulatory group, this may not be a reliable marker of more general deterioration in condition. Furthermore, there were four adverse events (three deaths, one hospital admission with deteriorating respiratory function) in the traditional care model group sugges...

Reduced survival in patients with ALS with upper airway obstructive events on non-invasive ventilation

“…NIV was initiated according to the current standardised procedure in the department over a period of 3–5 days17 (table 1). During the follow-up, the effectiveness of NIV was assessed in terms of symptoms (including NIV-related discomfort), blood gases, the analysis of ventilator-recorded tracings and nocturnal oximetry.…”