dysphagia Flashcards
How does swallowing occur?
2 phases oropharyngeal and esophageal. Oropharyngeal: voluntary and involuntary. in the voluntary phase we chew food into a bolus and pass it towards the back of the throat. In the involuntary phase, the upper esophageal sphincter relaxes, and the bolus is passed into the esophagus via coordinated and rapid action of pharyngeal and constrictor muscles.
Esophageal phase: peristaltic contractions with striated muscle in the upper esophagus and smooth muscle in the lower esophagus. Gravity helps. The LES remains closed until it gets a neural signal inhibiting its constituently active contraction.
Types of esophageal motility
- primary peristalsis pushing a bolus from the pharynx to the stomach in a sequential manner
- secondary peristalsis: reflux initiated that brings the food back down. Only in lower (smooth muscle) esophagus
Esophageal innervation
Striated muscle (top): innervated by somatic efferents of vagus nerve from the nucleus ambiguus. Distal esophagus: innervated by pre-ganglionic vagus nerve originating in the dorsal motor nucleus of CNX. Release ACh on excitatory and inhibitory neurons of myenteric plexus. Excitatory neurons are cholinergic; inhibitory neurons are us NO as dominant neurotransmitter. Peristalsis = coordinated excitation and relaxation
Distinguish btw dysphagia due to oropharynx problems or esophageal problems
choking; solids easier than liquids: think oropharynx
liquid easier than solids: think esophagus stricture.
If no choking or aspiration and difficulty swallowing solids AND liquids, consider esophageal motility problem. Location of perceived obstruction: usual location is at or below where the pt points as perceived level of obstruction.
odynophagia, or painful swallowing, suggests ulcerations.
important to note if difficulty is intermittent or progressive.
Associations with dysphagia in medical hx
heartubrn, collagen vascular disease, radiation therapy, meds, tobacco use (consider CA), immunosuppression,
ask about: nasal reguritation or tracheal aspiration, odynophagia, chest pain, weight loss
Oropharyngeal dysphagia: symptoms, basic causes
Usually has a neuromuscular basis
Pts show drooling, inability to chew food, nasal regurgitation, choking, repetitive swallowing. Solids are easier than liquids.
MANY potential causes (myasthenia gravis, myotonic dystrophy, sarcoidosis, CT diseases, stroke, CP, Guillain-Barre, huntington’s, MS, ALS, dementia, PD_. May be structural, iatropgenic.
Dianosis of oropharyngeal dysphagia
usually pts have other sx of underlying neuromuscular disease. do endoscopy if you suspect structural problem. MODIFIED barium swallow (series of swallows of various volumes and consistencies of contrast) to look for aspiration, excessive delay in swallow initiation, residue of ingestate in the pharyngeal cavity.
oropharyngeal dysphagia tx
dx and tx of underlying disorders
manipulate diet: thicken ingested liquids
swallow therapy
feeding tubes that bypass oropharynx (nasoduodenal tubes or PEG tubes)
Structural causes of oropharyngeal dysphagia (3 main ones. detail including definition, tx, and complications on some)
tumors
Zencker’s diverticulum: high bolus pressures hit an area of anatomic weakness in the pharynx. this causes mucosal protrusion. Bolus goes into this blind protusion preferentially, instead of down the esophagus. May lead to ulceration, bleeding, or aspiration. Treatment is usually surgical with success rates over 90%.
cricopharyngeal bar: Fiber degeneration and intestitial fibrosis of cricopharngeus muscle. Can only be identified as a cause of swallowing difficulties if all other causes have been ruled out or there is a known neuromuscular dysfunction that is acting synergistically to cause symptoms.
cricopharyngeal myotomy
most common surgical procedure for oropharyngeal dysphagia that works best in pts with limited opening of the crycopharyngeus muscle in association with preserved pharyngeal contractility (Zencker; webs)
globus sensation and xerostomia
globus sensation: painless feeling of a bolus in the back of the throat in which food bolus transport isn’t impaired. Though distressing to the pt, reassure them- it usually gets better. Often sensation is relieved by eating.
Xerostomia: decr. salivary secretion: esp. in elderly, Sjogren’s syndrome, post-radiation to head and neck
tests for esophageal dysphagia
- EGD (esophagogastroduodenoscopy) Gold standard for dx of mucosal disease. requires moderate sedation. May cause bleeding, infection, adverse rxn to sedatives, and perforation.
- Barium esophagram: Better than EGD in detection of subtle rings and strictures; may help with spasm and achalasia. Gives info about length and tightness of a stricture.
- Esophageal manometry: gold standard for dx of esophageal motlitty disorder. consider for ppl w/o structurs or mucosal diseas on EGD. doesn’t often ater management.
Main benign esophageal strictures
peptic, schatzki ring, pill or caustic injury, radiation induced injury that thicekns/narrows the esophagus, eosinophilc esophagitis, infectious esophagitis, esophageal web.
Peptic structures
GERD complication: acid induced ulcerations–> collagen deposition and fibrosis.
reduced now due to PPIs.
tx: stricture dilation + chronic acid suppression.
Schatzki’s ring
thin circumferential fold of mucosa covered with squamous epithelium from above and columnar epithelium from below. composed of mucosa and submucosa only: no muscularis propria. often associated with hiatal hernias.
tx: dilation or distruption of ring using biopsy forcepts. give PPI to lower recurrence rates
