GI Disorders - Exam IV Flashcards
The GI tract constitutes ____ of the total human body mass
5%
What are the main functions of the GI tract?
- motility
- digestion
- absorption
- excretion
- circulation
Outermost to innermost layers of the GI tract
serosa - longitudinal muscle layer - circular muscle layer - submucosa - mucosa
Mucosa layers (outermost to innermost)
muscarlis mucosae, lamina propria, epithelium
The ____ is a smooth membrane of thin connective tissue and cells.
What does it do?
Serosa - it secrets serous fluid to enclose the cavity and reduce friction b/w muscle movements
The ____ ____ ____ contracts to shorten the length of the intestinal segment.
longitudinal muscle layer
The ____ ____ ____ contracts to decrease the diameter of the intestinal lumen.
Circular muscle layer
What 2 layers work together to propagate gut motility?
- longitudinal muscle layer
- circular muscle layer
Innervation of the GI organs up to the proximal transverse colon are supplied by the ____.
Celiac Plexus
Innervation of the descending colon & distal GI tract comes from the ____ ____ ____.
Inferior hypogastric plexus
How can the celiac plexus be blocked?
- transcrural
- intraoperative
- endoscopic ultrasound-guided
- peritoneal lavage
The ____ ____ lies b/w the smooth muscle layers.
What does it do?
Myenteric plexus - it regulates the smooth muscle
The submucosal plexus transmits information from the ____ to the ____ & ____.
Epithelium
Enteric
Central Nervous Systems
What is the muscalaris mucosa & what does it do?
A thin layer of smooth muscle in the mucosa of the GI tract
Functions to move the villi.
What is the lamina propria? What does it contain?
The middle layer of the mucosa of the GI tract.
It contains blood vessels & nerve endings.
True or False - there are immune & inflammatory cells in the mucosa of the GI tract.
True
What happens in the epithelium of the GI mucosa?
- where the GI contents are sensed
- enzymes are secreted
- nutrients are absorbed
- waste is excreted
What is the GI tract innervated by?
Autonomic nervous system
The extrinsic nervous system has ____ & ____ components.
SNS & PNS
The extrinsic SNS is primarily ____ & ____ GI motility
inhibitory & decreases
The extrinsic PNS is primarily ____ & ____ GI motility.
excitatory & activates
What is the independent nervous system in the GI tract?
What does it control?
Enteric Nervous System
Controls motility, secretion, & blood flow
The enteric system is comprised of the ____ ____ & ____ ____.
Myenteric Plexus & Submucosal Plexus
What does the myenteric plexus control? How is it carried out?
Controls motility
carried out by:
* enteric neurons
* interstitial cells of Cajal (aka ICC cells, GI pacemakers)
* smooth muscle cells
What does the submucosal plexus of the enteric nervous system control?
absorption, secretion, & mucosal blood flow
What do the myenteric plexus & submucosal plexus respond to?
Sympathetic and parasympathetic stimulation
Upper GI Endoscopy
- May be diagnostic or therapeutic
- Endoscope placed into esophagus, stomach, pylorus, and duodenum
- done w/ or w/o anesthesia
Anesthesia challenges with upper GI endoscopy
- sharing airway w/ endoscopist
- procedure performed outside of the main OR - don’t have all the bells & whistles
Colonoscopy
- may be diagnostic or therapeutic
- w/ or w/o anesthesia (rare)
Anesthesia Challenges w/ Colonoscopy
- pt dehydration d/t bowel prep & NPO status
- renal & CHF pts can be problematic when they are dry
- MAC (monitored anesthesia care) - BP drops w/ propofol
High Resolution Manometry (HRM)
- pressure catheter measures pressure along the entire esophageal length
- used to Dx motility disorders
- anti-reflux procedures
GI series w/ ingested Barium
- radiologic assessment of swallowing function
- GI transit
- series of pictures taken under fluoroscopy
Gastric emptying study
- pt fasts for at least 4 hours
- consumes a meal (eggs) w/ a radiotracer dye in it
- used to dx gastroparesis/problems emptying the stomach
Small Intestine manometry
- catheter measures contraction pressures & motility of small intestine
- evaluates contractions during 3 periods:
(fasting, during a meal, post-prandial) - recording time: 4hrs fasting, ingestion of meal, 2hrs post-meal
- abnormal results grouped into myopathic or neuropathic causes
Lower GI series
- involves the admin of a barium enema
- barium outlines the intestines & is visible on radiograph
- allows for detection of colon & rectal abnormalities
Examples of anatomical causes of esophageal disease:
What do they interrupt?
- diverticula
- hiatal hernia
- changes associated w/ chronic acid reflux
* they interrupt the normal pathway of food & change pressure zones of esophagus
Examples of mechanical causes of esophageal disease
- achalasia
- esophageal spasms
- Hypertensive LES (lower esophageal sphincter)
Examples of neurological causes of esophageal disease
- stroke
- vagotomy
- hormone deficiencies
Most common Sx of Esophageal Disease
- dysphagia
- heartburn
- GERD
Dysphagia
Difficulty swallowing
2 types
Oropharnygeal dysphagia
common after head & neck surgeries
Esophageal Dysphagia - 2 types
Classified based on physiology
* esophageal dysmotility: sx occur w/ both liquids & solids
* mechanical esophageal dysphagia: sx only occur w/ solid food
GERD (Gastroesophageal Reflux Disease)
Pt experiences effortless return of gastric contents into pharynx
Sxms: heartburn, nausea, “lump in throat”
What is Achalasia?
- one of the most common esophageal diseases
- neuromuscular disorder of esophagus
- outflow obstruction d/t inadequate LES tone & dilated hypomobile esophagus
Causes of Achalasia:
- loss of ganglionic cells of the esophageal myenteric plexus
- absence of inhibitory neurotransmitters of the LES
- Unopposed cholinergic LES stimulation (LES can’t relax)
- Esophageal dilation w/ food unable to pass into stomach
What do people w/ achalasia have an increased risk of long-term?
esophageal cancer
Diagnosis for Achalasia
esophageal manometry
esophagram
Symptoms of Achalasia:
- dysphagia
- regurgitation
- heartburn
- chest pain
- hard time getting food to pass adequately
Type 1 Achalasia
minimal esophageal pressure
* responds well to myotomy
Type 2 Achalasia:
entire esophagus pressurized
* responds well to treatment
* has the best outcomes
Type 3 Achalasia
esophageal spasms w/ premature contractions of the esophagus
* has the worst outcomes
Achalasia Tx
- ALL TREATMENTS PALLIATIVE
- Meds: nitrates, CCBs - relax LES
- endoscopic botox injections
- pneumatic dilation - most effective (balloon dilation)
- Laparascopic Hellar Myotomy - best surgical tx
- peri-oral endoscopic myotomy (POEM)
- esophagectomy - only for advanced dx
POEM: peri-oral endoscopic myotomy & risks
- endoscopic division of LES muscle layers
- 40% develop pneumothorax or pneumoperitoneum
All achalasia pts are ____.
What is indicated b/c of this?
- high risk for aspiration
- RSI or awake intubation (full stomach)
Diffuse Esophageal Spasms
- spasms that occur in the distal esophagus
- d/t autonomic dysfunction
- occur more in elderly
- Dx: esophagram
- pain mimics angina
Tx for diffuse esophageal spasms
NTG, antidepressants, PDE-I’s
What are Esophageal Diverticula
outpouchings in the wall of the esophagus