Spinal Muscular Atrophy (SMA) Type 1 Survival Without New Pharmacotherapies: Two Treatment Paradigms

Abstract

Abstract Objectives To present noninvasive respiratory management outcomes using continuous noninvasive ventilatory support (CNVS) and mechanical in-exsufflation (MIE) from infancy for SMA type 1 and to consider bearing on new medical therapies. Design NVS was begun for consecutively referred symptomatic infants with SMA type 1 from 1 to 10 months of age. Intercurrent episodes of respiratory failure were managed by intubation then extubation to CNVS and MIE despite failing ventilator weaning and extubation attempts. Intubations, tracheotomies, and survival were monitored. Results Of 153 patients with SMA1 consecutively referred since 1995, 37 became CNVS dependent, almost half before 10 years of age. Of the 37, 18 required CNVS for a mean 18.6 ± 3.3 years to a mean 25.3 (range 18-30) years of age, dependent from as young as 4 months of age with 0 to 40 ml of vital capacity. One of the 18 died from COVID-19 ARDS at age 24 after 23 years of CNVS. Extubation success rate of 85% per attempt (150/176) resulted in only one undergoing tracheotomy. Conclusion Medical treatments begun during the first 6 weeks of age convert SMA1 into SMA2 or 3 but cough flows remain inadequate to avoid many pneumonias that, once resolved by a treatment paradigm of extubation to CNVS and MIE, eliminates need to resort to tracheotomies.