, infection, trauma, multiple sclerosis, brainstem lesions, lateral medullary ischaemia.[8, 9]Psychogenic - shock, fear, excitement, attention-seeking behaviour.[10]Irritation of the diaphragm - eg, subphrenic abscess, hiatus hernia.[5, 11]Vagus nerve irritation - eg, tumours, goitre, pharyngitis, meningitis, glaucoma.[4, 12]Phrenic nerve irritation.[10]After surgery - eg, gastric stasis, direct irritation