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Flashcards in GI Pathophysiology Deck (73):
1

True or false: this was the worst lecture all year

True

2

What is responsible for vasoconstriction of arterial blood flow to the G.I. tract?

Sympathetic nervous system

3

What two things enhance mechanical activity of the GI tract?

Distention and parasympathetic nervous system stimulation

4

What is the normal pH range for gastric fluid?

1-3.5

5

What are some symptoms of vagal stimulation during an abdominal procedure?

Bradycardia
Decrease contractility
Vasodilation
Decreased blood pressure
Increased bowel mobility

6

What can you do when there is vagal stimulation during an abdominal procedure?

Tell the surgeon to quit dicking around
Give glycopyrrolate

7

What two things put the patient at high risk for aspiration pneumonitis?

Volume > 25 mL
pH < 2.5

8

What is the relationship between the pH and volume and severity of aspiration pneumonitis?

Dose-dependent relationship in the severity of AP for both volume and acidity that reaches the lung

9

What are some potential reasons for reduced airway reflexes and thus increased risk for perioperative AP?

Pregnancy, obesity, GERD, MS, MD, MG, ALS, (Stroke)

10

What are some methods for reducing the risk of regurgitation and pulmonary aspiration?

RSI
Increase emptying
Decrease volume and acidity
NG/OG tube
H1 and H2-blockers
Minimize intake

11

What are the fasting guidelines for clear liquids in adults and children?

Adults >3 hours
Kids >2 hours

12

What are the ASA fasting recommendations for breastmilk and nonhuman milk/light meals preoperatively?

Breast milk >4 hrs
Light meals >6 hrs

13

Why is gum not allowed preoperatively?

It increases gastric volume and decreases pH

14

How could gum potentially be helpful post-op?

Prevent post-op ileus

15

What is peristalsis?

Wavelike movements of the bowel in a forward direction

16

How long is the average adult esophagus?

8 inches or 20 cm

17

What is the purpose of the upper esophageal sphincter?

Prevents aspiration of gastric contents into the lung and swallowing of air

18

What effect do most anesthetic agents have on UES tone?
What is the exception?

Most anesthetic agents decrease you UES tone
Ketamine increases

19

What is zenker's diverticulum?

Diverticulum of the mucosa of the pharynx just above the cricopharyngeal muscle

20

What type of maneuver cannot be performed on patients with a zenker's diverticulum?

Selleck (cricoid pressure)

21

What leads to gastroesophageal reflux?

Decrease in lower esophageal sphincter tone

22

What is the resting pressure of lower esophageal sphincter tone?
At what point is LES pressure problematic?

Normal: 15-30 mmHg
Problem: <10 mmHg

23

What is barrier pressure?

Difference between gastric pressure and LES pressure

24

What effect does cricoid pressure have on LES tone?

Decreases

25

List some factors that decrease LES tone

Inhaled anesthetics
Opioids
Anticholinergic
Propofol
Beta blocker
Hiatal hernia
Pregnancy
Obesity

26

List some factors that increase LES tone

Anti-cholinesterase
Cholinergic
Acetylcholine
Metoclopramide
Histamine
Serotonin
Metoprolol

27

What is an EGD?

Esophagogastroduodenoscopy

28

What is heartburn?

Incompletely closed lower esophageal sphincter allows acidic stomach contents to reflux into the esophagus

29

What is gastroesophageal reflux disease (GERD)?

When reflux occurs frequently or is bothersome

30

What is Barrett's esophagus?

Regular reflux of stomach acids irritates the esophagus, which may lead to histological changes and progress to malignancy

31

What is achalasia?

The LES does not relax properly

32

What is true of all general anesthetics in patients with achalasia?

RSI

33

What is esophageal stricture?

A narrowing of the esophagus

34

What are the risk factors for esophageal cancer?

Smoking, heavy drinking, chronic reflux

35

What is esophageal varices?

Dilated veins in the distal esophagus are at risk for serious bleeding

36

What is the main cause of esophageal varices?

Portal hypertension

37

What is the treatment for portal hypertension and hepatic encephalopathy?

TIPS Transjugular intrahepatic portosystemic shunt

38

In the event of an upper G.I. perforation early diagnosis and surgical management within what timeframe is best?

Within 12 hours

39

Upper GI perforation is associated with what mortality if delayed 24 hours?
....48 hours?

24 hrs --> 50%
48 hrs --> 90%

40

What is the function of the stomach?

Food storage and initial digestion
NOT Nutrient absorption

41

How is the stomach innervated?

Vagus

42

What is the pyloric sphincter?

Opening from the stomach into the small intestine

43

What is the surgical treatment option for GERD and hiatal hernias?

Nissen fundoplication

44

What is a nissen fundoplication?

When the upper portion (fundus) of the stomach is wrapped around the lower esophagus

45

What happens to FRC, PIP, PaCO2, and PaO2 during Laparoscopic procedures?

Decrease FRC
Increase PIP
Increase PaCO2
Decrease PaO2

46

At what intra-abdominal pressure is there a decrease in venous return?

>15

47

Why is there a potential for shoulder pain during laparoscopic procedures?

Referred pain from stimulation to the phrenic nerve

48

Where does most digestion and absorption occur?

Small intestine

49

Parasympathetic simulation will have what effect on small intestine activity?

Increased activity

50

How much chyme is produced on a daily basis?

1 to 2 L/day

51

What effect do hypokalemia, peritonitis and laparotomy have on small intestine activity

All decrease activity for up to 48 hours

52

What is celiac disease?

Autoimmune disorder that destroys the villi in the small intestines

Causes a reaction to eating gluten

53

What is Crohn's disease?

Autoimmune inflammatory bowel disease

54

How much can the gallbladder store?

50mL

55

Opioid effect what structure in the gallbladder?
How can this affect be reversed?

Sphincter of oddi
Reversed with glucagon or narcan

56

What is cholelithiasis?

Gallstones can lead to rupture

57

What are some potential causes of pancreatitis?

Alcohol abuse, blockage, trauma, autoimmune, hyperparathyroidism cystic fibrosis

Propofol can cause at high doses

58

What is one of the most common causes of emergency abdominal surgery?

Appendicitis

59

What is an ERCP?

Endoscopic retrograde cholangiopancreatography
-View the entrance of the common bile duct

60

Where are water and electrolytes absorbed?
Where is feces stored?

The colon

61

Colonic secretions have what type of pH?

Alkaline

62

What type of inflammatory bowel disease usually begins in the rectal area and may involve the entire large intestine?

Ulcerative colitis

63

What is diverticulosis?

Small pouches in the lining off the colon, or large intestine, that bulge outward through weak spots

64

What is diverticulitis?

When the patches of diverticulosis become inflamed

65

What are some complications associated with diverticulosis?

Bleeding, abscess, perforation, peritonitis, fistula, obstruction

66

What is important to know about carcinoid tumors?

They secrete hormones

67

60% of carcinoid syndrome cases present as what?

Carcinoid heart disease
-Right sided involvement (Tricuspid regurge and pulmonary valve involvement)

68

What is important for the management of carcinoid syndrome?

Block histamine and serotonin receptors
Avoid histamine releasing drugs
Fluid resuscitation
Monitor electrolytes and glucose
Octreotide-somatostatin infusion

69

What are the life-threatening causes of agitation during a MAC case?

Hypoxemia
Hypovolemia
Local toxicity
Cerebral hypoperfusion

70

What are the four categories used to gauge the depth of a MAC case?

Responsiveness
Airway
Spontaneous ventilation
Cardiovascular

71

What effect does glucagon have on the sphincter of oddi?

Relaxes it

72

What are some of the pros and cons for using ketamine during MAC anesthesia?

Pros: Analgesia, CV stability
Cons: Patient may move, hallucinate, drool

73

Why might glycopyrrolate be given in conjunction with ketamine?

To control secretions