3.3 Gastrointestinal System 3.3.1 Dysphagia Ref: Davidson P. 851, Andre Tan Ch3, WCS51 A. Physiology of Dysphagia Dysphagia: difficulty in swallowing Swallowing: function of clearing food and drink through oral cavity, pharynx and oesophagus into stomach at an appropriate rate and speed Phases of swallowing: □ Oral phase: voluntary → Mastication of solids → form food bolus → Tongue movement to achieve glossopalatal seal → push food bolus or fluid against hard palate □ Oropharyngeal phase: involuntary → Activation of mechanoreceptors of pharynx → initiation of swallowing reflex → Soft palate elevates (levator veli palatini) → nasal cavity closed off → Larynx elevates (suprahyoid muscles) → larynx closed off (by epiglottis) → Pharyngeal muscles contract → food bolus delivered from pharynx into oesophagus □ Oesophageal phase: involuntary → Peristaltic movement of muscularis propria → food bolus delivered into stomach Dysphagia can be classified as □ Oropharyngeal dysphagia → difficulty with initiation of swallowing → Usually functional (i.e. due to neuromuscular diseases) □ Oesophageal dysphagia → failure of peristaltic delivery of food through oesophagus → Can be functional or mechanical (i.e. due to mechanical obstruction) - Page 193 of 360 - B. Approach to Dysphagia Oropharyngeal Oesophageal Functional Diseases of CNS: Primary motility disorders: Bulbar palsy, pseudobulbar palsy, Parkinson’s Achalasia, diffuse oesophageal spasm, nutcracker disease oesophagus153, hypertensive LES Diseases of motor neurones: Secondary motility disorders: Motor neurone disease, peripheral neuropathy, Diabetic neuropathy, scleroderma, Sjogren’s poliomyelitis, syphilis syndrome, multiple sclerosis Diseases of NMJ/muscles: Myasthenia gravis, myopathies (muscular dystrophy, polymyositis, dermatomyositis) Mechanical [NOT COMMON] Intraluminal causes: Mural causes: Foreign bodies, lower oesophageal rings154, oesophageal webs Pharyngeal pouch, oropharyngeal tumours, strictures Extramural causes: Mural causes: Oesophageal tumours, oesophagitis (peptic, Goitre, lymphadenopathy, cervical osteophytes, retropharyngeal abscess radiation, chemical, infectious, drug-induced), strictures (long-standing oesophagitis, malignant) Extramural causes: Anterior mediastinal masses (thyroid, thymus, teratoma, terrible lymphoma), CA lung, TB, cardiovascular (rare)155 1. History 153 Nutcracker oesophagus refers to normal oesophageal peristaltic wave but at an increased intensity. 154 Lower oesophageal (Schatzki’s ring) is a lower oesophageal narrowing due to presence of a ring of mucosa. 155 Cardiovascular causes of extraluminal obstruction include thoracic aorta aneurysm (dysphagia aortica), aberrant Rt subclavian a. (dysphagia lusoria) and LA dilatation (dysphagia megalatriensis). - Page 194 of 360 - Is it real dysphagia? □ Globus hystericus: anxious people feel a lump in throat without organic cause □ Odynophagia: pain during swallowing (can coexist with but ≠ dysphagia) Which phase of swallowing is affected? Oropharyngeal Oesophageal - C/O difficulty in initiating swallowing - C/O food getting stuck in throat or chest - A/w nasal regurgitation, choking and coughing - Region localized is poorly correlated with exact - A/w other neurological signs: site of abnormality Nasal speech (soft palate paralysis) - Note that oesophageal dysphagia my perceive location at cervical region mimicking oropharyngeal dysphagia Drooling of saliva Dysarthria, diplopia - A/w recurrent aspiration pneumonia What type of pathology is causing the dysphagia? Mechanical Functional Onset Can be gradual or sudden Usually gradual Progression Often Variable C/O Difficulty swallowing solid >> fluid Difficulty swallowing solid + fluid Response to Usually passes with drinking liquid or Often regurgitation bolus repeated swallowing Variation with None May vary with temperature temperature Intermittent? Webs, rings, oesophagitis, Diffuse oesophageal spasm, nutcracker CVS compression oesophagus Progressive? Strictures Achalasia Others Other relevant Hx (eg. tumour) Hx of stroke, neuromuscular disease Is it painful? – odynophagia suggestive of □ Oesophagitis: drug-induced, radiation, infectious, reflux Causes of infective oesophagitis: □ Caustic ingestion Healthy: Candida albicans, HSV □ Late CA oesophagus HIV: fungal, viral, mycobacteria, protozoan, ulcers Are there any red-flag features of CA oesophagus? □ RFs: smoker, drinker, chronic GERD, Barett’s oesophagus, achalasia, FHx… □ Dysphagia: recent onset, progressively worsening □ Odynophagia (late feature) □ UGI bleed □ Constitutional symptoms: loss of weight (also in achalasia), loss of appetite, anaemic symptoms □ Local invasion: hoarseness (RLN), T-spine bone pain (vertebral), fever/cough/haemoptysis (trachea), massive haematemesis (aorta) □ Metastasis: neck lump, jaundice, bone pain Any suggestive features of individual causes? Oropharyngeal dysphagia Oesophageal dysphagia - Page 195 of 360 - Functional Functional - Hx or features of neurological diseases, - Hx or features of systemic sclerosis, eg. eg. stroke, myopathies Calcinosis, Raynaud’s, (Esophageal 156 Mechanical dysmotility), Sclerodactyly, Telangiectasia - Reflux symptoms, eg. heartburn, acid/water Mechanical brash, ↑when lying down → reflux strictures - Reflux symptoms, eg. heartburn, acid/water - Halitosis → pharyngeal diverticulum brash, ↑when lying down → reflux strictures - Hx of caustic ingestion - Drug Hx: tetracyclines, NSAIDs, KCl, alendronate → drug-induced oesophagitis Any complications? □ Malnutrition □ Aspiration pneumonia: fever, cough, SOB (esp at night) □ Tumour spread: hoarseness, bone pain, haemoptysis, neck lump, jaundice… 2. Physical Examination General condition: □ Level of alertness and cognitive status → risk of aspiration? □ Vitals, dehydration → hypovolemia from vomiting or ↓intake □ Cachexia → nutritional status □ Pallor → UGIB due to tumour, peptic ulcer or oesophagitis □ Jaundice → liver mets Examination to look for causes: □ Neurological exam for any CN5, 7-12 palsies, PD features, myopathy □ Neck exam for any neck mass □ Bedside swallowing test for direct observation of act of swallowing □ Surgical scars on abdomen/chest for previous surgeries or RT □ Abdominal exam for any palpable mass (not likely) □ PR exam for any melena Examination to look for any complications: □ Aspiration pneumonia: febrile, septic-looking, lung crepitation, ↓AE (usually RUL) □ Metastasis: cervical LN, hepatomegaly, ascites Any treatment already given? □ Tube feeding via NG tube, gastrostomy, jejunostomy → look at the colour of aspirate □ TPN 156 Strictly speaking, CREST syndrome is the limited cutaneous form of systemic sclerosis. - Page 196 of 360 - 3. Investigations OGD: first-line for oesophageal dysphagia □ Advantage: allows direct visualization, allow tissue Bx (esp in malignancy), allow therapeutic interventions, eg. treat bleeding, stents □ Disadvantage: should NOT be used if suspecting webs or diverticula (risk of perforation) Barium swallow for OGD negative but still suspect mechanical obstruction □ Advantage: less invasive than OGD □ Disadvantage: dangerous if at risk of aspiration □ Possible findings: → Bird’s beak (rat’s tail) sign in achalasia → Oesophageal diverticulum or pharyngeal pouch → Shouldering in stricture (smooth if benign, right-angled if malignant) → Corkscrew appearance in diffuse oesophageal spasm High resolution manometry (HRM) for OGD negative but still suspect functional obstruction □ 36 circumferential channels each with 12 sensors down oesophagus □ Gold standard for assessing oesophageal motility □ Reading a manometry contour plot: → Vertical = distance down oesophagus → Horizontal = time □ Chicago classification - Page 197 of 360 - Video fluoroscopic swallowing study (VFSS) and fibreoptic endoscopic evaluation of swallowing (FEES) for oropharyngeal dysphagia □ VFSS: fluoroscopic examination of swallowing of liquid, paste and solid with barium contrast □ FEES: nasal endoscopic examination during swallowing process □ Allow assessment of penetration and aspiration of various consistencies of food during swallowing □ Limited to cervical oesophagus 4. Initial Management Stabilize patient: □ Resuscitate if haemodynacmically unstable □ IV fluid to correct fluid deficits and electrolyte derangement □ Nutrition: fluid-only (if can tolerate), NPO157 + NG tube/TPN (if cannot tolerate fluid) □ Treat aspiration pneumonia: NPO + IV Abx Ix and treatment of underlying cause 157 NPO = nil per os, i.e. nothing taken by mouth. - Page 198 of 360 - 3.3.2 Upper GI Bleeding Ref: Davidson P. 853, Andre Tan Ch5, WCS52, 57 A. Causes of Upper GI Bleed Common causes Uncommon causes Peptic ulcer disease* (most common) Oesophageal Gastro-esophageal varices* Oesophageal tumour Gastritis or duodenitis Stomach 158 Gastric malignancies Portal hypertensive gastropathy, GAVE , Dieulafoy’s lesion*159 Oesophagitis Small bowels Mallory-Weiss syndrome Aortoduodenal fistula160*, angiodysplasia, GI stromal tumour (GIST)161, diverticular bleeding, Crohn’s disease Biliary tree Haemobilia (due to PTBD), haemosuccus pancreaticus162 *Causes that can give rise to severe bleeding Peptic ulcer disease: accounts for ~25-50% of non-variceal UGIB □ Site: duodenal, gastric, oesophageal, stomal (eg. jejunal side of gastrojejunostomy) → Ulcers high on lesser curve and in postero-inferior wall of D1 bleed more easily (penetrate into Lt gastric and gastroduodenal aa. respectively) □ S/S: variable bleeding ± previous epigastric discomfort □ Suggestive features: → Hx of dyspepsia