Nursing 1005 Flashcards
1
Q
List Examples of Biomolecules
A
Proteins, Lipids, Polysaccharides, Nucleic acids, Hormones, Metabolites
2
Q
What are Monosaccharides?
A
Smallest unit of carbohydrates.
This includes glucose, fructose, deoxyribose, ribose and galactose.
Combines to form diasaccharides.
3
Q
What are Disaccharides?
A
Forms from two monosaccharides and water removed.
This includes lactose, sucrose, maltose.
4
Q
How are Diasaccharides absorbed?
A
They are hydrolyzed in the Small Intestine to form Monosaccharides which is absorbed across intestinal wall into the bloodstream
5
Q
What are Polysaccharides?
A
Chain of simple sugars linked together via dehydration synthesis.
Includes Glycogen, starch and cellulose.
6
Q
Use of Polysaccharides in the body - What is Gluconeogenesis?
A
Used as storage products.
Glycogen is stored in muscle and liver and is release as glucose into the blood when needed
7
Q
What are Lipids?
A
Organic molecules which are insoluble in water.
Examples includes triglycerides, phospholipids and cholesterol.
8
Q
Describe the process of food passing through the digestive system
A
Food –> Mouth –> Teeth (Mechanical Breakdown) –> Salivary glands excrete saliva containing enzymes that chemically breakdown food –> passes by the pharynx into the oesophagus –> Stomach (continues to chemically and physically breakdown food –> food released to small intestine –> signals release of enzymes stored and produced in the accessory digestive organs (liver, gall bladder, pancreas) –> most nutrients will be absorbed in the Small Intestine where water is absorbed —> waste leaves the body via the rectum and anus
9
Q
What is the function of the Digestive System
A
- Reduce particle size
- Helps to absorb micro nutrients and trace elements
- Sets a phyical and immunologic barrier
10
Q
What does digestion break down?
A
- Carbohydrates (starch and sugar) –> single sugar molecules
- Proteins –> amino acids
- Fats –> fatty acids, glycerol
11
Q
How is food moved through the digestive system?
A
Via peristalsis
12
Q
What is the role of saliva?
A
Contains:
- Amylase to break down starch (inactivated in the stomach)
- Lipase begins fat digestion
- Mucus lubricates the food for easier swallowing
- Lysozyme kills bacteria
13
Q
What is the function of the oesophagus?
A
- Connects pharynx to stomach
- Peristalsis occurs due to muscle contraction
- Lower oesophageal sphincter stops food from re-entering the oesophagus from the stomach
14
Q
What is the function of the stomach?
A
- Lower OS and plyoric sphincter control entry and exit from stomach
- secretion of HCL, enzymes including protease, gastric lipase; mucus, hormone gastrin and intrinsic factor (B12)
15
Q
What is the function of Stomach Acid?
A
- Activates digestive enzymes - pepsinogen activated –> pepsin (enzyme that digest proteins)
- Assists in calcium absorption
- makes dietary minerals soluble for absorption
16
Q
Function of the Small Intestine
A
- Most digestion and absorption occurs here
- Folded walls with villi projections
- Absorptive cells are located on the villi
17
Q
Digestive System – The Process of Absorption
A
- Through SI walls
- Absorbed into blood (water soluble nutrients), Lymph (fat soluble nutrients)
- Blood –> liver (detoxifies and repackages) –> general circulation
18
Q
What is the function of the Large Intestine?
A
- No villi or enzymes present
- Little digestion occurs
- Absorption of water, some minerals, vitamins
- Bacteria break down fibre; produce vitamin K
- Formation of faeces for elimination
19
Q
What is the function of the Rectum?
A
- Stool remains and stimulates nerve endings for elimination
- Muscle contraction and the opening of the anal sphincter to elimination
- Voluntary control
20
Q
What is Nausea?
A
- Sensation of the need to vomit
- Prolonged nausea is debilitating and cause physiological strain
- Can be result of both physical and physiological
21
Q
Causes and Diagnosis of Nausea
A
- Anything that slows GI motility can cause nausea
- Result of stimulation of the SNS which decreases blood flow to the GI tract
- Pain, motion, disease and certain medications can also cause nausea
- Diagnosis is difficult, however, its known to be cause by stimulation of the vomiting centre of the brain
22
Q
What is Vomiting?
A
- Forceful emptying of stomach contents and intestinal chyme through the mouth
- Vomiting centre is stimulated in the brain which triggers the vomiting reflux
- Stimuli includes severe pain, distention of the stomach or duodenum and trauma to the testes, ovaries, bladder or kidney
23
Q
What is Diarrhoea?
A
- Increased frequency of defecation and fluidity of volume of faeces
- There are different types of diarrhoea include Steatorrhea (fat in stools) may occur in malabsorption syndromes
- Systemic effects may includes dehydration, electrolyte imbalance, metabolic acidosis and weight loss
24
Q
What is Osmotic Diarrhoea?
A
- Occurs when substance in the intestine can’t be absorbed and instead draws water into the lumen via osmosis
- Examples include lactase deficiency (when ingested cannot be absorbed in the small intestine), and Sorbitol (Non absorbable synthetic sugar)
25
What is Secretory Diarrhoea?
- Caused by excessive mucosal secretion of fluid and electrolytes or inhibition of NaCl absorption
- Can be caused by bacterial endotoxins (e.g. cholera), IBD, Crohn's disease and neoplasms (cancer)
26
What is Constipation?
- Difficulty defecation or infrequent
- Caused by function or mechanical problems (muscle weakness or pain)
- Diet of highly refined foods and low fibre can result in constipation
27
Gastrointestinal Bleeding
- Need to determine whether its upper or lower GI tract
- Severe bleeding may cause hypovolemic shock
- Clinical manifestations include haematemesis (vomiting blood), Occult blood, Melena (black, foul smelling), Haematochezia (bright red)
- Complications include Diarrhoea, anaemia, elevated blood urea nitrogen (indicates injury of the kidney - due to the digestion of blood proteins - UGI bleed)
28
What is Anorexia?
- Lack of desire to eat despite physiologic stimuli that would normally produce hunger
- Accompanied by end stage cancer, heart disease, kidney failure, liver failure
29
What is Abdominal Pain?
- Caused by mechanical or chemical stressors
- May be visceral or referred
- Visceral pain is caused by inflammation/injury to an abdominal organ - pain is poorly localised and dull until the nerve endings are overwhelmed
-Referred pain is visceral pain which is felt some distance from the affected organ - usually localised and felt in skin or deeper tissues that share a central afferent pathways with the affected organ, e.g. gall bladder apin referred to the back between the scapulae
30
What is Mechanical Dysphagia?
- Difficulty swallowing
- Caused by mechanical (can be intrinsic and extrinsic) obstruction
- Intrinsic obstruction may originate in the wall of the oesophageal lumen
- Extrinsic obstruction may originate outside the oesophageal lumen and narrow the oesophagus by pressing inwards on the oesophageal wall
31
What is Functional Dysphagia?
- Difficulty swallowing
- Neural or muscular disorder that interfere with swallowing and oesophageal peristalsis
- May be caused by disorders that affect muscles in the upper oesophagus which interferes with voluntary swallowing, Dermatomyositis (muscle disease), neuro impairment from CVA, Parkinson's disease
32
What is Gastro Oesophageal Reflux Disease (GORD)?
- Reflux of chyme from the stomach to the oesophagus
- Usually lower OS maintains a zone of high pressure to prevent chyme reflex
There are different types of reflux - physiologic reflux (There are no symptoms) and Reflux Oesophagitis (inflammatory response to reflux)
- Vomiting, coughing, lifting and bending increases abdomoinal pressure and relfux incidence
- Delay in gastric emptying contributes to reflux and increasing the acid content of chyme
- Gastric and duodenal ulcers may also delay gastric emptying by causing pyloric oedmea and narrowing
- Presence of hiatal hernia can also contribute to reflux by weakening the lower OS
33
Clinical manifestation of COPD in Adults
- Heartburn
- Acid Regurgitation
- Dyshagia (difficulty swallowing)
- Chronic cough
- Asthma
- Upper abdominal pain within 1 hour of eating
Often symptoms worsen when individual lies down or intra-abdominal pressure increases
34
Clinical manifestation of COPD in infants
- Excessively vomiting during first week of life
- Aspiration pneumonia
- Chronic cough
- Anaemia
35
What is intestinal obstruction?
- Failure of normal intestinal motility
- Prevention of the flow of chyme through intestinal lumen
- May be due to mechanical obstruction e.g. tumour
36
Describe the pathophysiology of Bowel Obstruction
- increase in fluid and gas may accumulate in the bowel proximal to the obstruction
- leads to development of inflammation and oedema of the bowel
- odema can lead to large amounts of fluid moving to the bowel which can result in hypovolemic shock
- electrolyte imbalances may occur
37
What is Acute Gastritis?
Acute inflammation of gastric mucosa
- infection
- NSAIDS (Nonsteroidal anti-inflammatory drugs) use which inhibits protective prostaglandin secretion resulting in decreased mucous production and surface erosion
- mucosal injury from drugs
- alcohol and histamine release contribute to surface erosion
38
What is Chronic Gastritis?
Inflammation of gastric mucosa
- occur predominantly in the elderly and results in degeneration of stomach wall
- this occurs due due to autoimmune cause, helicobactor pylori bacterium and chronic bile reflux
39
What is Peptic Ulcer Disease?
Breakdown and ulceration of protective mucosal lining
- occur in the oesophagus, stomach or duodenum
- imbalance between gastric acid production and mucosal barrier protection is an important factor in the development of PUD
- Duodenum ulcers are most common
40
What factors increase gastric acid production?
- increase in the number of parietal/chief cells
- decrease in the inhibition of gastric secretions
- increased sensitivity to food/other stimuli such as caffeine and histamine
- excessive vagal (one of the cranial nerves) stimulation
41
What factors impair mucosal barrier protection?
- Ischemia can lead to loss of integrity of the mucosa, smoking can also lead to vasoconstriction reducing blood supply
- Sympathetic stimulation will decrease secretions
- Bile or pancreatic enzyme reflux from duodenum
- protective prostaglandin secretion is inhibited by NSAIDS
- Alcohol consumption
- H. Pylori colonization
42
Describe the Diverticular disease of the colon
- Diverticula are small herniations that occur through the muscle layer of the colon wall (commonly sigmoid colon)
- many patients will be asymptomatic
- Diverticulitis is defined as the inflammatory stage of diverticulosis
43
Describe the pathophysiology of Diverticular Disease
- Patient present with history of low fibre, which leads to reduced faecal bulk, reduce colon diameter thus increasing the pressure on the colon wall
- pressure leads to development of outpouchings at weak points of the colon walls
44
What is Appendicitis?
Inflammation of the Vermiform appendix
- obstruction of the lumen of the vermiform appendix with hardened with faecal matter, a tumour or foreign body leads to development of an enclosed environment where bacteria divide rapidly causing infection
- Increased oedema due to inflammation increases the pressure within appendix
- ischemia and hypoxia develop and ulceration can occur
- Rupture of the appendix, peritonitis and abscess formation may develop
- Most serious complication is peritonitis - inflammation of the membrane lining the abdominal wall and covering the abdominal organs
45
What is Peritonitis?
Inflammation of the peritoneum
- results from contamination of the space between the parietal and visceral layers of the peritoneum (which is normally sterile) by chemical or infectious agents
- often result from bacteria
- inflammation may result in fluid shifts in peritoneal space
- leads to hypovolemic shock and hypovolemia developing
- Septicaemia (bacteria in the blood) & septic shock may also occur
46
Define Maldigestion
It is the failure of the chemical processes in digestion which break down food
47
Define Malabsorption
It is the failure of the intestinal mucosa to absorb the nutrients that have been made available from digestion
48
Clinical manifestation of Malabsorption Syndromes
- Diarrhoea or Steatorrhea
- Abdominal distention and cramping
- Weight loss and weakness
- Anaemia and bone pain
- muscle cramps
- tendency to bleed/bruise easily
49
Explain Bile salt deficiency
Conjugated bile salts are needed to emulsify and absorb fats and fat soluble vitamins
- bile salts may occur from cholesterol in the liver
- decrease in bile salts may occur when there is either liver disease or bile obstruction
Symptoms include
- fatty stools
- Diarrhoea
- Deficiency in fat-soluble vitamins
50
What enzymes does the pancreas produce?
- Pancreas produces the enzymes lipase, amylase, trypsin and chymotrypsin
51
List the fat soluble vitamin deficiencies
```
Vitamin A
- Night Blindness
Vitamin D
- Decreased calcium absorption, bone pain, fractures and osteoporosis
Vitamin K
- Prolonged prothrombin time, purpura and petechiae
Vitamin E
- Unknown
```
52
What is lactase deficiency?
Inability to break down lactose into monosaccharides thus lactose can't be digested
- leads to fermentation of lactose by bacteria resulting in gas production and osmotic diarrhoea
53
What is Inflammatory Bowel Disease (IBD) ?
Diseases with malabsorption e.g. Crohn's disease and ulcerative colitis
- Several factors are thought to contribute to the development of these diseases including
- Genetics
- Alterations to epithelial barrier functions
- Immune reactions to intestinal flora
- Abnormal T cell reponses
54
Describe the "Elderly Mouth"
Older ppl have
- loss of tooth enamel and dentin which can lead to pin during eating
- lost teeth
- denatures
- Periodontal disease and gum recession is common
55
Age related changes to digestion
As we age the number of taste bud decline which can make most foods taste bland
- elderly have a diminished sense of smell which also can lead to food seeming less appealing
- salivary secretions decrease and thus they are more prone to gum disease
- swallowing is more difficult and carbohydrate breakdown in the mouth decreases
- have decrease in the motility of both the oesophagus and the stomach which can lead to feelings of nausea and difficult in moving food through the upper GI tract
