Gastrointestinal Flashcards
Which parasympathetic effects take place in the GI system?
Relaxation of GI sphincters, increased GI motility and digestive juices, promotion of urination and defecation, formation of glycogen from excess glucose and in reverse by increasing insulin production
What’s the receptor zone responsible for vomiting called?
CTZ
How do prokinetics (metoclopramide, domperidone) work?
The enhance GI motility by increasing the frequency and strength of contraction. Has dopamine antagonist actions via D2 receptors
Prokinetics indications
Controlling nausea and vomiting. Facilitates introduction of tubes or biopsy capsules
Prokinetics nursing considerations
Shouldn’t be used for longer than 12 weeks. Should be withheld 3 to 4 days post GI surgery as wound healing may be inhibited by vigorous contraction
What kind of drug is Ondansetron?
5-HT3 Receptor Antagonist
How does Ondansetron work?
It blocks the 5 HT3 receptors (serotonin receptors) hence reducing the effect of serotonin in inducing vomiting
Ondansetron nursing considerations
Causes electrolyte imbalances. Monitor pulse and ECG and for serotonin syndrome
How do antihistamines treat GI problems?
They are H1 receptors antagonists with anticholinergic and antiemetic actions
What are the general side effects of laxatives?
Nausea, bloating, cramps, diarrhoea with prolonged use and excessive water loss and electrolytes
Which contraindications are common across all laxatives?
Intestinal obstruction, faecal impaction, bowel perforation, paralytic ileus and undiagnosed rectal bleeding
What four groups of laxatives are there?
Bulk-forming
Faecal softening
Stimulants
Osmotic and saline
What are two common causes of diarrhoea?
Infectious agents in the GI tract and side effects of NSAIDs and antibiotics
What are short acting treatments for diarrhoea?
Opioid antidiarrheals such as loperamide and codeine
What does PUD stand for?
Pectic Ulcer Disease
How do antacids work?
They buffer or neutralise hydrochloric acid in the stomach and thereby raise the pH, making the stomach more alkaline
How do cytoprotective drugs work?
They enhance the protection of the stomach lining provided by the mucus layers of the gastric and duodenal mucosa
Which suffix indicates a H2-Receptor antagonist?
tidine
What do H2-receptor antagonists do?
Reduce gastric acid secretion by competitively blocking the action of histamine H2 receptor sites of parietal cells
H2-Receptor antagonist indications
GORD
Which suffix indicates a proton pump inhibitor?
prazole
How do proton pump inhibitors work?
They supress gastric acid secretion by inhibiting the proton pump at the secretory surface of the gastric parietal cells
Which two kinds of drugs are normally used to resolve PUD?
Proton pump inhibitors
Antibiotics
What does IBD stand for?
Inflammatory bowel disease
What does UC stand for?
Ulcerative colitis
What does CD stand for?
Crohn’s Disease
