Final Flashcards
What is the most common secretory diarrhea we see clinically?
Diarrhea caused by cholera or cholera-like toxins including heat-labeled toxin of E. Coli
Where are the majors sites of endogenous enzymatic digestion?
- Mouth
- Stomach
- Cranial duodenum
- Small intestinal brush border
The total daily amount of fluid entering the gut roughly equals the animal’s _______ volume.
ECF
About ____% of water that goes into the gut is absorbed before excretion.
99
How do crypt cells work?
As they undergo division, they take in NaCl from the interstitium, then the Na is recycled back into the ECF leaving a net negative electric charge inside cell causing Cl to diffuse out of dell into the intestinal lumen.
How do villus cell work?
They pump NA out of their ICF into the interstitium which causes a negative charge within the cell promoting the diffusion of luminal Na into the cell. Cl enters the cell as well in exchange for HCO3…water follows the ions from bicarbonate into the lumen.
What can cause maldigestion diarrhea?
- Poor chewing/mixing
- Poor digestive enzyme
- Poor acid production
What can cause malabsorption diarrhea?
- Loss of surface area of the gut
2. Thickening of the gut wall
What is exudative diarrhea
Result of inflammatory processes affecting the bowel where there is some loss of mucosal integrity leading to leakage of protein, plasma or blood into the guy lumen, or abnormal build up of pressure and protein in the tissue.
What type of diarrhea is the most severe?
Exudative
If there is an increase in peristalsis with a decrease in intestinal transport time, how does this contribute to diarrhea?
It can decrease the time for digestion and absorption to take place
If there is a decrease in peristalsis or mixing motility decreases contact with digestive/absorptive areas, how can this contribute to diarrhea?
It can promote bacterial overgrowth and fermentation leading to inflammation or the generation of secretagogues or osmotic earth compounds.
Which types of diarrhea involve direct tissue damage?
Malabsorption/maldigestion diarrhea and exudative diarrhea
Which type/types of diarrhea do not cause direct tissue damage?
Secretory
Syncope
Sudden, transient loss of consciousness resulting in collapse with spontaneous recovery caused by transient global cerebral hypoxia
How soon does loss of consciousness occur once blood flow stops?
10 seconds
What are some causes of cardiac syncope?
- Arrhythmias
- Obstruction to flow
- Low output
- Cyanotic heart disease
- Tamponade
What are some causes of neurologic syncope?
Increased intracranial pressure reducing cerebral perfusion
What are some causes of Metabolic syncope?
- Abrupt decrease in oxygen delivery
2. Abrupt decrease in nutrient delivery (glucose
What are some causes of tussle/cough syncope?
- Reduced venous return
2. Stimulation of vagal efferents producing bradycardia and vasodilation
What are causes of autonomic dysfunction syncope?
Neurocardiogenic
Bradyarrhythmias
6-8 second pause in hearts electrical activity
Tachyarrhythmias
Heart rate greater than 300bpm for more than 6-8 seconds
What types of bradyarrhythmias can cause syncope?
- High grade AV node block
- Sick sinus syndrome
- Atrial standstill
What types of tachyarrrythmias can cause syncope?
- Supraventricular
- Ventricular
- Arrythmogenic cardiomyopathy
What types of obstruction to outflow of blood can cause syncope?
- Pulmonic valve stenosis
2. Subaortic stenosis (more common)
What causes of low cardiac output can cause syncope?
- Dilated cardiomyopathy
2. Severe mitral regurgitation
What types of cyanotic heart disease can cause syncope?
- Tetralogy of Fallow ( R to L PDA) resulting in hypoxemia
By definition, syncope is ____ and ______.
Short and transient
Supraventricular tachyarrythmias and labradors is sick sinus syndrome to ____________.
Miniture schnauzers and dachshunds
Which breed(s) of dog is most likely to have ventricular tachycardia that causes syncope?
- Doberman
2. Boxers
What is usually the cardiac cause of syncope in older, small breed dogs?
Chronic degenerative valve disease
What is usually the cardiac cause of syncope in Boxers, golden retrievers and german shepards?
Subaortic stenosis
A dog is experiencing syncope due to dilated cardiomyopathy, what type of dog is this most likely?
Giant breed dogs
On physical exam, what are signs of cardiac disease?
- Murmur
- Arrhythmias
- Altered pulse character or quality
- Cyanosis
- Evidence of heart failure
How do you treat bradyarrhythmias?
Pacemaker with sympathomimetic and vagolytic medications
How do you treat supra ventricular tachycardias if you want to abolish the arrhythmia?
Na+ channel blockers like the class 1 a drugs ( procainamide and quinidine)
How do you treat supra ventricular tachycardias if you want to slow the arrhythmia?
- Digoxin
- Ca channel blockers
- Beta blockers
All slow AV nodal conduction
What is the treatment for ventricular arrhythmias?
- Class Ib drugs like lidocaine and mexiletine
2. Class III drugs like sotalol
What is the treatment for an outflow obstruction issue that is causing syncope?
Use fluoroscopy and then medical/surgical management
What is the treatment for low cardiac output that is causing syncope?
Positive inotrope meds or beta blockade with exercise restrictions
What is the treatment for tussive syncope?
- Hydrocondone
- Butorphanol
Cough suppressants
Dysphagia
Difficulty or painful swallowing stemming from the oral/pharyngeal regions
Regurgitation
Passive retrograde expulsion of food/fluid from the oral/pharyngeal cavity or esophagus
Vomiting
Forceful ejection of food/fluid through the mouth from the stomach or proximal duodenum that involves abdominal muscle contraction and heaves.
How is swallowing initiated?
By voluntary passage of a bolus into the retropharynx leading to an involuntary pharyngeal phase trigger
Which nerves are required for swallowing?
Cranial nerves VII, IX, X, and XII ( facial, glossopharyngeal
, vagas, and hypoglossal)
What are the phases of swallowing?
- Orophayrngeal ( with Oral, pharyngeal, and cricopharyngeal stages)
- Esophageal
- Gastroesophagesal
During the oropharyngeal phase of swelling, which parts are voluntary versus involuntary?
The oral phase is voluntary and the pharyngeal and cricopharyngeal are involuntary
What can cause dysphagia?
- Pain during pretending or swallowing
- Mechanical obstruction of oral cavity/pharynx
- Neuromuscular dysfunction
- Feline Lymphoplasamacytic stomatitis
- Ranula
What is the most important differential to remember when a dog is experiencing dysphagia?
Rabies
What usually accompanies pharyngeal and cricopharyngeal dysphagia?
Esophageal motility disorders
What are some clinical signs of oral dysphagia?
- Inappetent
- Turkey poking or gobbling food
- Dropping food
- Tilting head back
- Chewing on one side
What are the most common causes of oral dysphagia?
- Dental/Periodontal disease
- Trauma like mandibular fracture and TMJ dysfunction
- Inflammatory disease like lymphoplasmacytic stomatitis
- Ranulas
In 50% of cats that are FIV positive, what may also occur that causes oral dysphagia?
Feline Lymphoplasmacytic stomatitis
What is a ranula, what does it do and how do you treat it?
A sublingual mucocele that causes mechanical obstruction leading to dysphagia and treatment with marsupializtion
How is feline lymphoplasmaxytic stomatitis treated?
Partial or full-mouth tooth extraction
Medical management with antimicrobials, antiinflammatorys or analgesics
What is pharyngeal dysphagia?
When there is trouble with the tongue bringing food back to the pharynx
What is cricopharyngeal dysphagia?
When there is no relaxation of the cricophyrngeus muscle which forms the upper esophageal sphincter
How is pharyngeal dysphagia and cricopharyngeal dysphagia diagnosed?
Fluoroscopy
What are the most common causes of pharyngeal and cricopharyngeal dysphagia?
- Congenital like cricopharyngeal achalasia
- Neurological disease like problems with the cranial nerves, brainstem, tick paralysis, polyradiculoneuropathy, and myasthenia gravis
What do you want to keep in mind when taking a history of an animal that is suffering from dysphagia?
- Age=older animal may be more systemic disease, young more congenital or foreign body
- Duration of signs=acute could be mechanical obstruction
3 Presence of other signs= CNS disease
During the physical exam, what behavior may you see with oral dysphagia?
Difficulty before swallowing and tilting/throwing head back while eating
During the PE, what behavior may you see with pharyngeal dysphagia?
Chews normally but repeatedly attempts to swallow while flexing or extending neck
During the PE, what behavior may you see with Cricopharyngeal dysphagia?
Starts to swallow then coughs/gags because bolus hits larynx due to tense cricopharynxgeus muscles (upper esophageal sphincter)
How do we treat dysphagia?
Medical/surgical management of underlying disorder
Feeding tube maybe
Treat aspiration pneumonia
What are the clinical signs of regurgitation?
- Increased appetite
- Weight loss/poor growth
- Animal may attempt to reconsume regurgitate material
What does regurgitation produce?
- Undigested feed
- Tubular shape
- Frothy saliva
How is regurgitation controlled?
It is a locally mediate process via mechanical events in the esophagus
A dog is suffering from systemic lupus erythematosus, is the dog most likely regurgitating or vomiting?
Regurgitation
Megaesophagus: regurgitation or vomit?
Regurgitation
Esophagitis: regurgitation or vomit?
Regurgitation
Hypothyroidism or Hypoadrenocorticism: Vomiting or regurgitation?
Regurgitation
What are some neuropathic that can cause regurgitation?
- Polyradiculoneruitis
- Lead poisoning
- Distemper
- Brainstem lesion
What is the hallmark sign of gastric disease?
Vomiting
Is vomiting a clinical sign or a disease?
clinical sign
How is vomiting controlled?
It is central mediated via the chemoreceptor trigger zone in the emetic center of the cerebrum. it is triggered by blood-borne drugs and toxins, indirectly via afferent nerves, and via the abdominal viscera attached to the vagus and sympathetic nerves.
What are the phases of vomiting?
- Nausea
- Retching
- Vomiting
During retching, there is _______ pressure in the thorax, and during vomitng there is ________ pressure in the thorax.
negative; positive
What happens in order for an animal to retch?
The abdominal muscles and diaphragm must contract
How long does acute vomiting last and what animals is it more common in?
Less than 7 days
In younger dogs and cats
At what frequency does an animal need to vomit in order for it to be considered chronic? What type of animals does the type usually occur in ?
More than once a day for more than 5 days OR
TWICE a WEEK for more than 2 WEEKS
Middle aged to older animals
What are the main electrolyte imbalances that can occur in a dog that is vomiting?
- Hypokalemia
- Hypocholremia
- Hyponatremia
Why do small animals not suffer from hypoglycemia when they are continually vomiting? Exceptions?
Endogenous glucose production
Puppies, toy breed dogs and emaciated animals
A cat comes into the clinic and it vomiting/regurgitating tubular casts…is this vomit or regurgitation?
In cats, they can throw up tubular casts under both situations. If this was a dog, tubular casts are more common during regurgitation.
Between dysphagia, regurgitation and vomiting, which ones commonly involve ptyalism?
Dysphagia and vomiting
Is white foam more common in regurgitation or vomiting?
Regurgitation
What are the major causes of weight loss/failure to thrive?
- Inadequate feed/water intake
- Poor quality feed/water source
- Inability/reluctance to eat/swallow
- Incomplete digestion or nutrient absorption
- Increased loss after absorption
- Increased metabolic demand
What are the causes of inadequate feed/water intake?
- Lack of availability
- Decreased ability to access feed
- Herd competition
- Animal:feed ratio is to high
- Weather influences
What could be the cause of poor quality of food/water source?
- Feed palatability is off
- Feeding straw
- Lack of knowledge of owners on what to properly feed a certain species
Why would an animal be inable or reluctant to eat/swallow?
- Poor dentition
- Feed palatability
- Oral trauma
- Esophageal trauma
- Neurologic disorder
- Musculoskeletal disorder
Why would an animal have incomplete digestion or nutrient absorption of their food?
- Poor dentition
- Small or large intestinal disease
- Pharmaceutical alterations
Why would an animal have increased loss of nutrients after absorption?
- Protein losing enteropathy
- Renal disease
- Sequestration/third spacing
What are some physiological reasons for increased metabolic demand in an animal?
- Pregnancy
- lactation
- Environmental extremes
- Breeding
- Exercise
What are some pathophysiologic reason for increased metabolic demand in an animal?
- Neoplasia
- Chronic laminitis
- Renal failure
- Liver disease
- Cardiac disease
- Respiratory disease
In order of most practical to least practical, name the diagnostic tests you can do on an animal that is losing weight and failing to thrive.
- History and Feed analysis
- General physical exam
- Oral exam
- Rectal exam with fecal evaluation
- Rebreathing exam
- Complete blood count/chemistry
- Serology
- Ultrasound
- Radiographs
- Abdominocentesis
- Endoscopy
- Biopsy
- Abdominal exploration
How do animals produce body heat?
- Muscle activity and cellular processes
- Sympathetic stimulation
- Digestion and fat metaboliziation
- Thyroxine (thyroid hormone)
What factors can affect thermoregulation of an animal?
- Age
- Ambient temperature
- Feeding times
- Reproductive cycles
- Accuracy of the measurement and device
How do animals preserve body heat?
- Reduce peripheral circulation
2. Behavioral changes like seeking shelter and huddling
What are some mechanisms that contribute to losing heat from the body?
- Conduction
- Convection
- Evaporation
- Radiation
- Increase peripheral circulation
- Behavioral changes like seeking out shade and water sources
What is conduction?
An object transfers heat to another object
What is convection?
Transfer of heat to either air or water
What is radiation?
Loss of heat from the ground and the sky
What is evaporation?
The loss of heat through saliva, sweat or panting especially when ambient temperature is high
How is heat transferred within the body to either lose it or gain it?
Circulatory convection
What is the overarching thermoregulatory organ of the body?
The anterior hypothalamus that is connected to a feedback loop between all the other organs and receptors of the body
What temperature are skin thermoreceptors more responsive to? Why is this advantageous?
COLD
If the temp is dropping and the receptors respond, the body can acclimate before the core body temperature is affected.
If an animal gets hot, what will the body start doing to cool down?
- Peripheral vasodilation
- Sweating
- Increased RR
If an animal gets cold, what will the body start doing to heat up?
- Peripheral vasoconstriction
- Erector pili reaction
- Increased muscle activity (shivering or getting put and moving
- Eating and finding shelter
In which patients is hypothermia more detrimental?
- Young
- Old
- Patients on certain medications and sedated
- Sick patients with systemic disease/infection/sepsis
What are the clinical signs of hypothermia?
- Low temperature
- Low RR
- Absence of shivering
- Decreased cardiac function with hypoxia
- Multi-organ failure
- Death
What are the causes of hyperthermia?
- Increased heat production
- Increased absorption of environmental heat
- Impaired ability to regulate body temp
When an animal has increased heat production, what could be causing this?
- Exercise (healthy if animal is trained regularly)
2. Malignant hyperthermia
Heat stroke is due to which causes of hyperthermia?
- Increased absorption of environmental heat
2. Impaired ability to regulate body temp
What animals are most at risk to heat stroke?
- Brachycepahlic and/or obese dogs
- Ruminants
- Adult horses in a very humid/hot environments that are exercising with improper conditioning beforehand
What are the clinical signs of heat stroke?
- Lethargic
- Not ambulating well
- Multi organ dysfunction/failure
- High temperature
- Vomiting/diarrhea
- Unresponsive
What are the treatments for heat stroke?
- Gradual cooling of the body
- IV fluid therapy with room temp fluid
- Oxygen therapy
- Support for organs that may have been damaged
How would an animal lose the ability to regulate body temperature?
- Trauma or some other damage to the anterior hypothalamus
2. Structural changes to the hypothalamus due to hemorrhage, infection, inflammation, edema, and neoplasia
If the hypothalamus is damaged, what clinical signs may you see in regards to hyperthermia?
- Loss in variation of ambient temperature especially when sleeping
- Not sweating
- Not responsive to anti-pyrettics
- As you start to cool the, there is a massive overcorrection of temperature
How/why is fever different than hyperthermia?
There is a change in the set point of temperature at the hypothalamus due to endogenous or exogenous pyrogens.
What can induce a fever in an animal?
- Exogenous activation of a pyrogen
2. Immune cell that activates a cascade that produces endogenous pyrogens
What substances are considered exogenous pyrogens?
- Viruses
- Bacterial infections
- Pharmacological agents (propofol left out, needle not clean)
- Tissue trauma
- Blood transfusions
- Toxins
What are some endogenous pyrogens?
- IL-1
- Neoplasia via paraneoplastic syndrome
- Abnormal tissue that becomes secondarily infected
- HYPP in horses
- Fat necrosis
- Hyperthyroidism
What are the benefits of fevers? (mild fever)
- Increased antibody production and immune system works more effectively
- Bacteria can’t grow as well as they can’t access iron stores in body
- Better survival when infected with a virus or bacteria with reduced morbidity
What are the disadvantages of fevers? (high fever)
- Damage to the immune system
- Increased metabolic activity that increases caloric need and body temp
- Suppress the appetite center
- Protein loss at GIT and kidneys
- High temps can damage organs like the heart and brain
Fever of unknown origin workup
- Take a history to see if the fever cycles..goes away and comes back again
- Physical exam -recurrent to see patterns
- Diagnostic tests like blood cultures and imaging
- Where are you in the country, changing infectious agents like fungus
What is a DDAVP trial?
It is a desmopressin test for diagnosing central diabetes insipidius that is run for 5-7 days
If the water intake is decreased during a DDAVP trial, what conclusion can you make?
The animal likely has central diabetes insipidus
If there is minimal change of water intake during a DDAVP trial, what conclusion can you make?
The animal is likely suffering from psychogenic polydipsia or primary nephrogenic polydipsia
Polyuria
Large amounts of urine
Pollakiuria
Frequent small amounts of urine
Incontinence
Lack of voluntary control of urinations aka enuresis
How much do dogs need to urinate in order for it to be considered polyuria?
More than 50 ml/kg/day
How much do cats need to urinate in order for it to be considered polyuria?
More than 40 ml/kg/day
How much water does a dog need to drink in order for it to be considered polydipsia?
More than 100 ml/kg/day
How much water does cat need to drink in order for it be considered polydipsia?
Greater than 45 ml/kg/day
How is urine concentrated?
ADH is prodded and released which leads to renal tubules responding to the ADH creating medullary hypertonicity
How is urine diluted?
Reduced or absent ADH production and then the renal tubules respond to the ADH and create an osmotic gradient between the renal tubules and the medullary interstitium
What is primary polyuria?
it is the failure of renal tubules to respond to ADH or reduced or absent ADH production or the reduction of the osmotic gradient between the renal tubules an the medullar interstitium
If primary polyuria is caused by a reduced or absent ADH production and release, what is the cause?
Central Diabetes insipidus
if primary polyuria is caused by the failure of the renal tubules to respond to ADH, what are the likely causes?
- Primary nephrogenic diabetes insipidus
2. Secondary nephrogenic diabetes insipidus
What is the most common cause of polyuria?
Secondary nephrogenic diabetes insipidus
If the osmotic gradient is reduced, what two factors will change?
- Sodium levels
3. BUN
What are causes of osmotic solute in the urine during primary polyuria?
- Normal concentration ability
- Diabetes mellitus
- Primary glucosuria
What are the causes of primary polydipsia with polyuria?
- Primary psychogenic polydipsia
- Liver failure
- Hyperthyroidism
What are some causes of primary polyuria that
- Hypercalcemia
- Hyperadrenocorticism
- Liver failure
- Pyelonephritis
- Pyometra
What are the causes of primary polydipsia in the absence of polyuria?
- Eating dry food
- Fever
- Elevated ambient temperature aka hyperthermia
What is the differential list for PU-PD?
- Diabetes mellitus
- Diabetes insipidus (central and nephrogenic)
- Hyperthyroidism
- Hyperadrenocorticism
- Hypercalcemia
- Kidney disease
- Liver disease
- Psychogenic polydipsia
- Hypokalemia
- Primary glucosuria
- Acromegaly
- Pyometra
- Drugs
You conduct a urinalysis on a dog and the SG is greater than 1.007, what may be going on?
- Psychogenic polydipsia
2. Diabetes insipidus
What is the urine specific gravity in most patients?
- Greater than 1.025
If you do a urinalysis and there is glucose, what could be going on?
- Dibetes mellitus
2. Primary glycosuria
If you do a blood chemistry panel, what three elements are you looking at to assess in PU-PD cases?
- Ionized calcium
- Potassium
- Creatinine
When working up a PU-PD case, what should you look at on blood chem panels besides the electrolytes and creatinine?
Test for synthetic liver function like BUN, cholesterol, albumin and glucose
What tests are helpful when working up a PU-PD case to rule out hyperadrenocorticism, hyperthyroidism , liver disease, acromegaly and pyometra?
- LDDS-hyperadrenocorticism
- T4 levels -hyperthyroidism
- Bile acids-liver disease
- IGF-1-acromegaly
- Ultrasound-pyometra
What test can be used to rule out early kidney failure when working up a PU-PD case?
SDMA
What is a water deprivation test used for?
When working up a PU-PD case, it can differentiate between central DI, nephrogenic DI, and psychogenic polydipsia
When should a water deprivation test not be used for a PU-PD case?
When the patient is experiencing:
- Azotemia
- Dehydration
- SG > 1.03 in dogs and > 1.04 in cats
What does the first stage of a water deprivation test entail?
3 days restriction of water to minimize medullary washout
What does the second stage of a water deprivation test entail?
Abrupt water deprivation requiring close monitoring with the goal to achieve maximal ADH secretion and concentration of urine at a loss of 3-5% body weight
If urine concentrates during the second stage of a water deprivation test, what is likely going on with the patient? What if it doesn’t concentrate?
Psychogenic polydipsia
Diabetes insipidus (central or nephrogenic)
How often should you monitor a patient during the second stage of a water deprivation test? What are you monitoring?
Every 1-2 hours
Do a PE, weight, empty bladder to check SG, BUN
Cr, PCV, TP, and electrolytes every 4-6 hours)
When is it time to stop a water deprivation test?
- Lost 5% of body weight
- Clinically dehydrated, vomiting, lethargic and with abnormal mentation
- Azotemic
- SG > 1.030
What does the their state of a water deprivation test entail?
This is the ADH response test where you give a DDAVP and check the SG
If the urine concentrates during the third stage of a water deprivation test, what does this mean? What if it doesn’t concentrate?
Patient likely has central diabetes insipidus if concentrating, but has primary nephrogenic DI if not concentrating
What does the last stage of a water deprivation test entail?
Over 6 hours, reintroduce water gradually to patient to avoid acute water overload and cerebral edema
What are some problems with water deprivation tests?
- Interpretation
- Misdiagnosis
- Can’t differentiate partial diabetes insipidus from psychogenic polydipsia
What are some complications of conducting a water deprivation test?
- Dehydration
- Acute kidney failure if patient has early renal disease
- Urosepsis if there is pyelonephritis
- Acute water overload and cerebral edema
How does cushings disease show up on a DDAVP trial?
There may be only a minimum or moderate response to the test
Compared to small versus large intestinal diarrhea, what will the fecal volume be like?
There will be increased fecal volume if the pathology is in the small intestine, but normal in the large.
Which four clinical signs are typically seen in a large animals suffering from diarrhea?
- Blood in stool
- Tenesmus
- Increased frequency if pathology in the large intestine
- Vomiting/coli is pathology is in the small intestine, rare in the large intestine.
A dog has mucous, no fat, normal color, no gas, and no weight loss. Is this diarrhea likely stemming from the small or large intestine?
Large
A cow has melana in the feces, along with vomiting, but is defecating at a normal frequency. Is this diarrhea likely stemming from the small or large intestine?
Small
How much gas will a small animal be experiencing if it has diarrhea stemming from the small intestine? Large?
Small: Occasional gas
Large: Rare
A cat is defecating frequently, but the volume is normal; however the diarrhea has fresh blood in it, but the color is normal. Where is this diarrhea stemming from?
The large intestine
If you noticed fat in a small animals diarrhea . what part of the intestines is likely diseased?
Small
If you noticed undigested food in a small animals diarrhea and the animals is losing weight, what part of the intestine is likely diseased?
Small
If a horse is struggling to defecating, but when it does there is diarrhea, what part of the intestines is likely diseased?
Large
The small intestine in a cat is damaged, what characteristics will you noticed with the behavior of the cat and the feces?
The cat will be losing weight, have gas, have increased fecal volume but normal urgency to defecate, will have undigested food with fat, the color will be variable and there won’t be any mucous.
The large intestine of a dog is damaged, what characteristics will you notice with the behavior of the dog and the feces?
The dog will not be losing weight, will not have gas, will have increased urgency to defecate but the fecal volume will be normal, there won’t be fat or undigested food, there may be mucous but the color will be normal.
