Introduction Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder characterised by degeneration of spinal cord anterior horn cells, leading to muscular atrophy. The authors report two cases of SMA type I.
Methods Descriptive case report. The patients were in the Pediatric Intensive Care Unit (PICU) of a tertiary medical center.
Results A 3 month-old female and a 5 month old male admitted to the PICU with acute respiratory failure and generalized muscular weakness. Chest X-ray showed a pulmonary atelectasis in both. Neurophysiology studies were performed, demonstrating an axonal motor polyneuropathy and signs of chronic denervation. Genetic analysis revealed homozygous state for a deletion of the survival motor neurone 1 (SMN1) gene. The first case started non-invasive ventilation and no intubation was necessary. The second case was intubated on admission. The weaning protocol was started with mechanically assisted cough via the tube and then extubation to continuous nasal ventilation and no supplemental oxygen. Both patients were discharged with nasal intermittent positive pressure ventilation.
Conclusions SMA Type 1 is a rare entity, but it is important for the pediatrician to be familiar with this disease because of its severe implications. The use of non-invasive ventilatory support associated with mechanical coughing aids can decrease the need for intubation and can also permit extubation and, thereby, decrease the need to resort to tracheostomy. With a non-invasive respiratory approach, these patients have a chance to develop the ability to communicate verbally and maintain some autonomous breathing ability.