Abstract

INTRODUCTION

If you ask a neurologist about neurological disorders and respiratory failure, you will get a more or less adequate list of the Guillain–Barré syndrome, myasthenia gravis, amyotrophic lateral sclerosis and even the exceedingly rare Ondine’s curse, but probably nothing much else. Respiratory failure is not our specialty’s forté, and neuromuscular respiratory failure is not common. However, every once in a while, an undiagnosed patient is encountered with laboured breathing. The response should be swift. Not only can apnoea be imminent, but pulmonary aspiration is equally life threatening.

Neurological disease can impair respiration at multiple levels (Fig. 1) (Kelly & Luce 1991). The interconnections between the respiratory centres, motor neurones, and the respiratory muscles provide a functional system that moves air in and out of the lungs. If it fails, it causes hypercapnia. The alveoli and pulmonary capillaries permit efficient gas exchange by diffusion through a paper-thin barrier; if