When should home mechanical ventilation be started in patients with different neuromuscular disorders?

Background and objectives: Current international consensus guidelines identify a number of indicators for the establishment of home mechanical ventilation (HMV) for patients with neuromuscular diseases but do not address the possible clinical differences between each of the underlying disorders. This study assessed the differences in the physiological parameters of patients with neuromuscular disease commenced on HMV for the treatment of symptomatic chronic hypercapnic respiratory failure. Methods: Patients commenced on HMV for the treatment of symptomatic chronic hypercapnic respiratory failure over a 9-year period were studied. Physiological parameters at the time of referral for HMV, impact of HMV and survival were analysed. Results: The study recruited 66 patients with neuromuscular disease. Thirty-one patients had rapidly progressive disease: amyotrophic lateral sclerosis (ALS, n = 19), Duchenne muscular dystrophy (DMD, n = 12) and 35 patients had slowly progressive disease. Mean FVC at HMV onset was 40.3 ± 17.5% predicted in all patients, but was >50% predicted in eight patients (12%). ALS patients were more hypercapnic (P = 0.03) and more hypoxaemic (P