Intro N/V Flashcards
1
Q
2 Major physiologic function of the GI system
A
Digest food
Absorb nutrient into the bloodstream
2
Q
describe the physiology of digesting food and absorbing nutrients?
A
- Food moves slowly along the digestive tract and are broken down into ions and molecules = absorbed into body through intestinal wall and into blood or lymph system
- un-absorbed nutrients and wastes are collected in the large intestine for elimination
3
Q
6 functions of the GI system
A
- Ingestion - Occurs when solid food and liquid enter the oral cavity
- Mechanical digestion and propulsion - crushing/shredding of food in oral cavity and mixing and churning in the stomach
- Chemical digestion - Chemical and enzymatic breakdown of food into small organic molecules that can be absorbed by the digestive epithelium
- Secretion - release of water, acids, enzymes, buffers, and salts by the digestive tract epithelium and by accessory digestive organs
- Absorption - Movement of nutrients across the digestive epithelium and into the bloodstream
- Defecation - Indigestible food is compacted into material waste that is eliminated by defecation
4
Q
3 parts of the GI system
A
- Upper - mouth, esophagus, stomach
- Where digestion starts - Middle - duodenum, jejunum, ileum
- Where most digestive & absorptive processes occur - Lower - cecum, colon, rectum
- Storage for elimination
5
Q
why is the GI system lined with permanent ridges and temporary folds?
A
increases surface area for absorbing nutrients
6
Q
what accessory organs produce secretions to aid in digestion?
A
salivary glands
liver
pancreas
7
Q
what is nausea?
A
- Subjective feeling of a need to vomit
- Vague, intensely disagreeable sensation of sickness or “queasiness”
8
Q
what spasmodic respiratory and abdominal movements usually follows nausea?
A
retching
9
Q
Oral expulsion of gastrointestinal contents due to ?
A
- contractions of gut and thoracoabdominal wall musculature
Multiple afferent and efferent pathways exist which induce vomiting
10
Q
The effortless reflux of liquid or food stomach contents
“Burping up” food contents
what is this term
A
regurgitation
11
Q
The chewing and swallowing of food that is regurgitated after meals
what is this term
A
rumination
12
Q
Normal function of the upper GI tract involves an interaction between what two things?
A
the gut and the CNS
13
Q
The motor function of the gut is controlled at three main levels:
A
- parasympathetic and sympathetic NS
- enteric brain neurons
- smooth muscle cells
14
Q
which is more bothersome and disabling, nausea or vomitting?
A
nausea
15
Q
what causes nausea?
A
Gastric Rhythmic Disturbance
- Nausea correlates with a shift in normal 3-cycle-per min gastric myoelectrical activity (muscle contraction and relaxation)
- 3 cycles/min of smooth muscle contraction in stomach
- This activity increases with a food bolus
16
Q
In disorders of stomach motility, the rhythm is (regular/irregular)?
A
irregular
17
Q
2 disorders of stomach motility, describe each
A
- Tachygastria: increased rate of electrical activity in the stomach
- >4 cycles/min - Bradygastria: decreased rate of electrical activity in the stomach
- <2 cycles/min
18
Q
Vomiting may be stimulated by 4 different sources:
A
- Afferent vagal fibers from GI viscera (serotonin 5-HT3)
- GI distention, mucosal or peritoneal irritation, infections - Fibers of vestibular system (histamine H1)
- sea-sick, dizziness - Higher CNS centers
- sights, smells, or emotional experiences - Chemoreceptor trigger zone
- stimulated by drugs, chemo agents, toxins, hypoxia, uremia, acidosis, radiation therapy
19
Q
what type and where are the chemoreceptor trigger zones that cause vomiting?
A
- opioid, serotonin 5-HT3, neurokinin 1 (NK1), and dopamine D2 receptors
- located outside blood-brain barrier in the area postrema
20
Q
what are the likely microbes that cause vomiting? include incubation period and likely food sources
A
- s. aures
- 1-6 h
- prepared foods, salads, dairy, meat - B. cereus
- 1-6 h
- rice, meat - norwalk-like viruses
- 24-48 h
- shellfish, prepared foods, salads, sandwiches, fruit
21
Q
In both urgent care and routine outpatient settings, the following 3 steps should be generally undertaken in pts with N/v
A
- find etiology, see if acute or chronic sx
- Correct any consequences/complications of N/V
- fluid depletion, hypokalemia, and metabolic alkalosis - Targeted therapy when possible
- surgery for bowel obstruction or malignancy
- symptomatic tx
22
Q
causes of acute sx w/o severe abdominal pain
A
- Inquiry should be made into recent changes in meds, diet, other GI symptoms, or similar illnesses in family members
- food poisoning
- infectious gastroenteritis
- drugs
- systemic illnesses
23
Q
causes of Acute onset of severe pain and vomiting
A
- suggests peritoneal inflammation
- acute gastric/intestinal obstruction
- pancreatobiliary disease
24
Q
causes of persistent vomiting?
A
suggests pregnancy
gastric outlet obstruction
gastroparesis
intestinal dysmotility
psychogenic disorders (think bulimia)
CNS/systemic disorders
25
recurrent episodes of N/V and abdominal discomfort in patients with prolonged marijuana use is called?
tx?
Cannabinoid Hyperemesis Syndrome
hot shower/bath
26
causes of morning vomiting?
pregnancy
uremia
alcohol intake
increased intracranial pressure
27
if a pt is Vomiting immediately after meals, what PE should you def do?
bulimia - TEETH EXAM
28
causes of Vomiting undigested food one to several hours after meals
1. gastroparesis
2. gastric outlet obstruction
- may hear a succussion splash
29
Acute or chronic sx you should ask about neurologic sx (CNS cause) with vomiting?
HA
stiff neck
vertigo
focal weakness/paresthesias
30
Feculent vomiting would indicate what?
Intestinal obstruction
31
what is Hematemesis?
Vomiting of blood or coffee-like material
32
labs for vomiting?
Screening tests can direct clinical care: severe or protracted vomiting
1. CBC - Infection, anemia
2. CMP - lyte disturbances, liver function, azotemia, met alkalosis from loss of gastric contents
3. Amylase, Lipase - Pancreatic enzymes
4. b-hCG
33
imaging for n/v?
Flat and Upright abdominal films: with severe or suspicion of mechanical obstruction
34
on abd film shows intestinal air-fluid levels w/ reduced colonic air
what is this?
small bowel obstruction
35
on abd film shows diffusely dilated air-filled bowel loops
what is this?
Ileus
36
If initial testing is non-diagnostic for n/v, may require anatomic studies:
1. EGD
- MC chronic N/V that is unexplained after routine evaluation---often normal
2. CT scan
3. Colonoscopy
4. US
5. MRI
6. GI motility testing
37
what additional anatomic study Detects ulcers, malignancy, retained gastric food residue, gastric outlet obstruction
EGD
exception, emergent hematemesis
38
what additional anatomic study Diagnoses partial SBO
CT scan
39
what additional anatomic study Detects colonic obstruction, malignancy, inflammatory conditions
Colonoscopy
40
what additional anatomic study Defines intraperitoneal inflammation, cholelithiasis
US
41
what additional anatomic study Can show inflammation in Crohn's disease
MRI
42
what additional anatomic study Can detect an underlying motor disorder when anatomic abnormalities are absent (Gastroparesis)
GI motility testing
can detect delayed gastric emptying
however, sx overlap with other GI disorders such as functional dyspepsia
43
complications of n/v
Volume Depletion/Dehydration
Electrolyte Disturbances
Aspiration
Mallory-Weiss Tear
Boerhaave Syndrome (Esophageal Rupture)
44
what macromolecule delays gastric emptying therefore should be avoided in foods when treating n/v?
lipids
Foods high in indigestible residue are avoided because these prolong gastric retention
45
tx for mild-moderate n/v?
- Clear liquids (broths, tea, soup, carbonated beverages)
- Advance to small quantities bland food (crackers)
- Antiemetic medication
Most causes are mild, self-limited and require no specific treatment
46
tx for moderate-severe n/v?
Hospitalization with IV (isotonic) fluids
Antiemetic medication
NG tube in certain situations (i.e. small bowel obstruction/gastric)
47
tx for pediatric n/v?
1. Infants and children with difficult IV/IO access may be hydrated with oral lyte solutions via NG tube
2. oral rehydration w/ 50–100 mL/kg of glucose–electrolyte solution x 4 hrs.
3. age-appropriate diet and breast-feeding may resume asap.
In either case, start with small doses of oral fluid and slowly increase the amount
48
tx for Severe volume depletion or hypovolemic shock from n/v?
Rapid rate of 1-2 L of isotonic fluids ASAP - restore tissue perfusion.
49
tx for Mild to moderate hypovolemia from n/v?
1. Rapid fluid resuscitation is not necessary
2. Induce _positive fluid balance_ = give fluid 50-100 mL/hr > estimated fluid losses
50
choices of replacement fluids?
Most pts are started initially on isotonic saline
1. Hypernatremia and hyponatremia - SLOW correction
- overly rapid correction is potentially harmful
2. Potassium replacement - for potassium depletion
3. sodium bicarbonate - met. acidosis
51
Caution with parenteral fluid bolus doses in following patient populations when tx fluid depletion/N/V:
infants, poor systolic EF, kidney disease, chronic severe hyponatremia (w/o neuro deficits that require hypertonic saline) and DKA in children.
52
indications for Ondansetron (Zofran)
1. Acute N/V
2. Postoperative N/V
3. Chemotherapy related N/V
4. Hyperemesis gravidarum?
- avoid in 1st trimester (rare chance of cleft palate)
53
caution with ondansetron (zofran) in who?
hepatic impairment
Pregnancy (1st trimester) - monitor
QT prolongation - monitor
54
SE of ondansetron
HA
Diarrhea/Constipation
Fatigue, malaise
Dizziness
Pruritus
55
class of Scopolamine (Transderm Scop)/Meclizine/doxylamine
Anticholinergic/antihistamines
56
indications for Scopolamine (Transderm Scop)/Meclizine/doxylamine
1. Motion Sickness, vertigo, migraines
2. combined with oral Vitamin B6 and doxylamine for pregnancy
3. Prevention postoperative N/V
57
what medication is recommended by American College of OBGYN 1st line therapy N/V with pregnancy
Scopolamine (Transderm Scop)/Meclizine/doxylamine
58
SE of Scopolamine (Transderm Scop)/Meclizine/doxylamine
xerostomia, urinary retention
dizziness
drowsiness, mydriasis
59
which medication
- 1st gen antihistamine; blocks H1 receptors - antiemetic and sedative effects
- special mention for Dopamine Receptor Antagonist (Phenothiazine); with H1 blocking as well
Promethazine (Phenergan)
60
which n/v med is available as a patch?
Scopolamine (Transderm Scop)/Meclizine/doxylamine
61
which n/v med should be administered with food, water, or milk to reduce GI distress
Promethazine (Phenergan)
62
PK of Promethazine (Phenergan)
Metabolized by the liver; CYP450
63
Serious SE of Promethazine (Phenergan)
serious
1. rsp Depression
2. Seizures
3. Leukopenia
4. Thrombocytopenia
5. Hallucinations
6. Extrapyramidal SE
- physical sx: tremors, uncontrolled muscle mvmts, slurred speech, akathisia (always moving), parkinsonism
7. Bradycardia
64
common SE of Promethazine (Phenergan)
Sedation
Blurred Vision
Confusion
Xerostomia
Dermatitis
Urinary retention
Constipation
65
which med has a BBW for Respiratory Depression and Tissue Injury/Necrosis
Promethazine (Phenergan)
66
CI of Promethazine (Phenergan)
rsp depression - children <2
67
caution with Promethazine (Phenergan)
Elderly
CNS depression
Asthma/COPD
Glaucoma
BPH
Cardiac Ds
Hepatic Ds
Seizure Ds
68
safety/monitoring for Promethazine (Phenergan)
Pregnancy Category: C
Obtain CBC, Ophtho exam with prolonged use
69
MOA of Metoclopramide (Reglan)
Increases peristalsis primarily by inhibiting dopamine
enhances response to acetylcholine of tissue in upper GI
enhances motility and accelerated gastric emptying
increases lower esophageal sphincter tone
70
which med is indicated for refractory GERD
Metoclopramide (Reglan)
N/V (adjunct), Gastroparesis, refractory GERD
71
which n/v med is renally excreted?
Metoclopramide (Reglan)
72
serious SE of Metoclopramide (Reglan)
1. Extrapyramidal SE
2. Neuroleptic malignant syndrome
- life threatening reaction characterized by F, autonomic dysfunction, altered mental status and muscle rigidity
3. Seizures
4. Depression/Suicidal Ideations
5. Leukopenia/Agranulocytosis
6. CHF, arrhythmias
7. HTN
73
common SE of Metoclopramide (Reglan)
Diarrhea
Drowsiness
Restlessness
Anxiety/Insomnia/Depression
HA/Dizziness
Hormonal Disorders
HTN
74
which med has a BBW of Tardive Dyskinesia
Metoclopramide (Reglan)
1. caused by use of neuroleptic drugs
2. involuntary, repetitive body movements, which may include
- grimacing
- eye blinking
- lip smacking
- abnormal mvmts of arms and legs
75
CI for Metoclopramide (Reglan)
Seizure Ds, GI obstruction
76
cautions with Metoclopramide (Reglan)
HTN
Parkinsons
CHF
Depression
DM
Renal Impairment
77
safety/monitoring for Metoclopramide (Reglan)
Pregnancy Category: B
CrCl at baseline
Do not abruptly discontinue - taper
78
what n/v med is used During chemotherapy with dexamethasone
Neurokinin receptor antagonists - Aprepitant (Emend)
79
what n/v med is used for Postoperative N/V; Chemotherapy
Additive agent
Dexamethasone
80
which med is use for anticipatory N&V with chemo?
Lorazepam - benzo (Xanax)
81
what med is given along with Zofran to help with Chemotherapy induced vomiting
Lorazepam
82
which n/v med is in the class of Serotonin 5-HT3 Receptor Antagonist?
Ondansetron (Zofran)
83
which n/v med acts on
5-HT3 receptors present both peripherally and centrally
Blocks serotonin from binding to 5-HT3 receptors
Blocking stimulation of “vomiting center” in medulla
Ondansetron (Zofran)
