CNS, Renal, And Hepatic Disease

Question 1

What are common Renal elective procedures?

Answer 1

Dental

Mass Removal

Question 2

What are common Renal Non-elective procedures?

Answer 2

Urethral stones
renal transplant
renal tumor

Question 3

What are common Renal Emergency procedures?

Answer 3

Feline urethral obstruction

Ruptured Bladder

Question 4

What are the three main functions of the kidneys?

Answer 4

Filtration
Reabsorption
Secretion

Question 5

How much cardiac output do the kidneys receive?

Answer 5

25%

Question 6

What does reabsorption depend on?

Answer 6

Aldosterone
ADH 
Renin-angiotensin
atrial natriuretic factor
prostaglandins
catecholamines

Question 7

What are kidneys sensitive to?

Answer 7

Ischemia

Hypoxia

Question 8

What is the constant mean arterial pressure of the Renal blood flow?

Answer 8

80-180mmHg

Question 9

What drugs should you avoid for the renal disease?

Answer 9

Anesthetics causing hypotension or requiring renal excretion
NSAIDs

Question 10

What Pre-op management should happen with Renal Compromise?

Answer 10

Fluid diuresis

Attention to electrolyte status (including Ca and Mg) with supplementation as necessary

Question 11

What Intra-op management should happen with Renal Compromise?

Answer 11

IV Fluids

MAP should be maintained about 70-80mmHg

Question 12

What is the fluid rate for renal compromised patients?

Answer 12

10mg/kg/hr

Question 13

What should you do first with a patient with Feline Urethral Obstruction?

Answer 13

Stabilize: Hyperkalemia and Hypovolemia

Question 14

How do you treat Hyperkalemia in a cat with Urethral Obstruction?

Answer 14

Calcium gluconate

Regular Insulin + dextrose

Question 15

How do you treat Hypovolemia in a cat with Urethral Obstruction?

Answer 15

Buffered isotonic IV fluids

Question 16

What drugs do you use in Feline Urethral obstruction?

Answer 16

Cardiovascular-sparing drugs: Opioids and Benzos

Question 17

What drugs do you avoid in Feline Urethral obstruction?

Answer 17

Ketamine

Question 18

What is the MAP that must be maintained for normal cerebral blood flow?

Answer 18

50-150mmHg

Question 19

What is the equation for Cerebral perfusion pressure?

Answer 19

MAP - ICP

Question 20

Cushing Reflex

Answer 20

Severe Increase ICP leading to poor cerebral perfusion
Leads to sympathetic response: vasoconstriction, increased cardiac output leading to hypertension
Carotid baroreceptors sense hypertension and cause reflex bradycardia
Increased ICP causes dysfunction of respiratory center causing irregular breathing pattern

Question 21

What are the preferred drugs for patients with CNS disease?

Answer 21

Do not increase ICP
cause seizures or lower seizure threshold
Decrease Cerebral blood flow

Question 22

Acepromazine - CNS effects

Answer 22

decrease seizure threshold

Question 23

Benzodiazepines - CNS effects

Answer 23

Decrease Cerebral Blood Flow and ICP

Control seizures

Question 24

Opioids - CNS effects

Answer 24

Minimal effects on Cerebral Blood Flow and ICP

Question 25

What are the side effects of Opioids?

Answer 25

Vomiting hypoventilation increase ICP

Question 26

What drug is used for CRI maintenance of anesthesia in CNS disease?

Answer 26

Propofol

Question 27

Etomidate - CNS effects

Answer 27

Decreases ICP, CBF< and CMRO2

Question 28

Ketamine - CNS effects

Answer 28

Increases ICP and CBF | May cause seizures

Question 29

Succinylcholine - CNS effects

Answer 29

Increases ICP

Question 30

What are the CNS effects of inhalational anesthetics?

Answer 30

at greater than 1 MAC increase CBF and ICP via cerebral vasodilation

Question 31

Which inhaled anesthetic has the greatest CNS effects?

Answer 31

Halothane

Question 32

What do you do for Intracranial disease during anesthesia?

Answer 32

Maintain straight neck and head slightly elevated Prevent vomiting/coughing Prevent hyperglycemia, hypercapnia, hypoxemia Conservative fluid recuccitation Mannitol before induction if increased ICP is suspected

Question 33

Trendelenburg-lie positioning

Answer 33

In horses: head down positioning in isoflurane anesthetized horses increases ICP by 80% and decreases CBF 20%

Question 34

Equine intracarotid injection

Answer 34

causes violent behavioral reaction and seizures

Question 35

How do you treat seizures from Equine Intracarotid injection?

Answer 35

Thiopental +/- guafenesin | Supplemental O2 and fluids

Question 36

What are the functions of the Liver?

Answer 36

``` Protein metabolism Carbohydrate metabolism Fat metabolism Vitamin storage Iron storage Produces coagulation factors Immune function Metabolizes Drugs, hormones, toxins ```

Question 37

What are the clinical signs of liver disease?

Answer 37

``` Depression anorexia weight loss Icterus ascites abnormal behavior seizures ```

Question 38

What drugs may worsen the signs of hepatic encephalopathy?

Answer 38

Benzodiazepines

Question 39

What are the drug considerations for Liver disease?

Answer 39

Liver metabolizes most anesthetic drugs so the drug action will be increased and/or prolonged Many drugs are highly protein bound so hypoproteinemia can will cause higher blood levels

Question 40

What are the pre-anesthetic considerations for Liver disease?

Answer 40

Optimize perfusion Correct hypoglycemia and electrolyte disturbances Abdominocentesis for ascites Blood type and crossmatch

Question 41

What drugs should you avoid in gallbladder disease?

Answer 41

Opioids

Question 42

What are the preferred drugs of liver disease?

Answer 42

Propofol Opioids Alfaxalone Etomidate

Question 43

Which inhalation anesthetic increases total hepatic blood flow?

Answer 43

Isoflurane

Question 44

What inhalation anesthetics decrease portal vein and total hepatic blood flow?

Answer 44

Sevoflurane | Des

Question 45

Which local anesthetics are metabolized by the liver?

Answer 45

Lidocaine Bupivicaine Mepivacaine

Question 46

Why is Acepromazine is contraindicated in liver disease?

Answer 46

Vasodilation Decreased BP Inhibits platelet aggregation

Question 47

Why are alpha 2 agonists contraindicated in liver disease?

Answer 47

Decreased CO

Question 48

Why are barbiturates contraindicated in liver disease?

Answer 48

Extensively redistributed, dependent on hepatic metabolism | Highly protein bound

Question 49

Why is halothane contraindicated in liver disease?

Answer 49

Decreased hepatic blood flow Metabolized by liver Hepatopathy

Question 50

Why is Succinylcholine contraindicated in liver disease?

Answer 50

Cholinesterases synthesized by liver

Question 51

Why is Guaifenesin contraindicated in liver disease?

Answer 51

Metabolized in liver | Metabolite (catechol) can cause toxic neuro effects

Question 52

What are the intra-op considerations for liver disease?

Answer 52

``` Maintain liver perfusion Monitor glucose Monitor hemorrhage Monitor depth of anesthesia, drug requirements may be decreased Maintain normal body temperature ```

Question 53

What are the Post-op considerations for liver disease?

Answer 53

Check acid/base status, electrolytes, glucose, and pcv/tp Maintain body temp Monitor for neurological abnormalities

Question 54

What is important for Portosystemic shunt ligation?

Answer 54

Arterial BP monitoring