Non-invasive ventilation outpatient set up in amyotrophic lateral sclerosis

Non-invasive ventilation (NIV) can improve survival in patients with amyotrophic lateral sclerosis (ALS). Scarce data exist on the preferred location of the initial titration. The aim of this study was to investigate whether a rapid access neuromuscular NIV service, where NIV is initiated in an outpatient setting, would be clinically effective. NIV set up data were collected between October 2018 and October 2019 in ALS patients treated as outpatients in a tertiary home ventilation centre. 83 ALS patients were referred in 12 months. The duration between diagnosis and referral was 4.5 (1.4, 12.8) months and between onset of symptoms and referral was 19.1 (11.7, 31.2) months. 5 patients died or received non-invasive ventilation prior to attending the rapid access outpatient service. The wait from referral to first appointment was 14 (8, 23) days. 48/83 patients (58%) were initiated on NIV at the first appointment: 65±12 years, FVC 1.68±0.78L, SNIP 26±13cmH2O, PCF 175±99L/min, and PaCO2 5.8±0.7kPa. 26 patients had orthopnoea. Adherence to NIV at first follow-up appointment or death [56 (30, 77) days; 2 deceased] was 0.5 (0.0, 6.2) hours. A difference in adherence was observed between patients with bulbar onset disease compared to those with limb onset [0.0 (0.0, 0.38) vs 4.6 (0.0, 8.0) hours; p=0.006]. FVC was different in adherent vs. non adherent patients (FVC: 2.35±0.62 vs. 1.44±0.78L; p=0.002). In conclusion, to streamline the ALS respiratory service, we have established a rapid access neuromuscular NIV outpatient set up. Over half of the patients were initiated on NIV at the first outpatient appointment. As expected, adherence to NIV was better in limb onset compared to bulbar disease.