what are the most common signs and symptoms of respiratory distress in a patient with a tracheostomy?
['Displacement of the tube.', 'Obstruction of the tube.', 'Patient — especially pneumothorax; also: pulmonary embolism, pulmonary oedema, collapse, bronchospasm.', 'Equipment — ventilator problems.', "'Stacked breaths' — a reminder about bronchospasm and ventilator settings."]