List the possible causes of an altered swallowing reflex in a critically ill patient, and outline how you could assess this.
• Iatrogenic - Medications – chemotherapy, antihistaminics, neuroleptics. Trauma - TOE, intubation , tracheostomy
• Infectious - candidial mucositis. Metabolic – thyrotoxicosis, Cushing’s
• Myopathic – myasthenia gravis, connective tissue disorders, myotonic dystrophy
• Neurological – severe head injury, stroke, Guillain-Barre syndrome. Structural - Zenker's diverticulum, Oropharyngeal and oesophageal tumours.
• History – hoarseness, weak cough – vocal cord palsy, slurred speech, nasal regurgitation – neuromuscular. Odynophagia – infections , malignancy
• Clinical assessment – oral cavity –poor dentition, dry mouth. Neurological –
cranial nerves – V. VII, IX, X, XI, XII.
• Bedside assessment by speech therapist – coordination of swallowing, aspiration of dye (methylene blue).
• Nasopharyngeal laryngoscopy – visual inspection oropharynx, vocal cords for anatomical abnormality.
• Video fluoroscopy – accurately analyses aspiration, pooling of secretions and movements of muscles during swallowing.
• Barium swallow – identifies anatomical abnormalities – diverticuli, tumours, Upper GI endoscopy.
Altered swallowing in an ICU patient could be the result of a number of aetiological processes. Not all of the belowmentioned processes are causing an "altered reflex" per se.
Drug-induced swallowing dyfunction:
Idiopathic miscellaneous causes:
Endocrine and metabolic causes:
Investigation of abnormal swallowing in ICU follows a familiar pattern:
- History (suggestive of stroke or malignancy)
- Examination (of whole body neurology, but focusing on the cranial nerves)
- Speech therapist assessment
- Nasendoscopy to observe the vocal cords directly
- Barium swallow
- CT of the neck
- A VFSS (videofluoroscopic swallowing study) is the gold standard.
de Larminat, Valentine, et al. "Alteration in swallowing reflex after extubation in intensive care unit patients." Critical care medicine 23.3 (1995): 486-490.
Macht, Madison, et al. "ICU-Acquired Swallowing Disorders." Critical care medicine 41.10 (2013): 2396-2405.