Anesthesia Final

What are the key components of the preanesthetic workup? List the five components that should be included in the preanesthetic assessment

Signalment, History, Physical exam, Diagnostics, ASA status

Why is it important to assess a patient’s medical history before administering anesthesia?

To make sure the patient has not had any complications or reactions to being put under anesthesia

List three components of a physical examination

MM, hydration status, temp

What diagnostic tests are commonly ordered prior to anesthesia, and what information do they provide?

CBC (hematocrit; platelet count), Serum chemistry (plasma proteins, electrolytes, BUN, Creatinine, Glucose, ALT, ALK), Diagnostic imaging (Radiographs, CT, shows broken bones, masses, or displaced organs, MRI, Ultrasound), Skin turgor test

Briefly describe the ASA status system, and how is it used to assess anesthetic risk in animals?

Scale to describe a patients anesthetic risk

1=minimal risk

2=slight risk

3=moderate risk

4=high risk

5= extreme risk

What does a pale or white mucous membrane indicate, and what might it suggest about an animal’s condition?

This indicates anemia, poor perfusion, or vasoconstriction and it is caused by blood loss, shock, decreases in peripheral vessel blood flow

What does a cyanotic (blue) mucous membrane suggest, and what might it suggest about an animal’s condition?

This indicates that the patient is not getting enough oxygen and it can be caused by hypoxemia

What could a yellow (icteric) mucous membrane indicate in an animal, and what might it suggest about an animal’s condition?

This indicates bilirubin accumulation and is caused by hepatic or biliary disorder and/or hemolysis

How much of a patient's body weight is water?

60%

This solution contains water and small molecular weight solutes and routinely used in anesthetized patients?

Crystalloid solutions

Define the term "Homeostasis" and list two principle rules for homeostasis.

-the constant state within the body is created and maintained by normal physiological processes. The two principal rules are electroneutrality and osmotic pressure.

Signs of overhydration

ocular/nasal discharge and coughing

Signs of dehydration

dry or tacky gums and loss of skin elasticity

List three reasons to use dextrose solutions.

neonatal, hypoglycemic, or debilitated patients

Please name two different types of colloids solutions used in veterinary medicine and

when to use these solutions

Synthetic colloid solutions=when shock, hypotension, and blood loss are present

Blood products= when anemia, hypoproteinemia, coagulation disorders, and thrombocytopenia are present

What is the safe PSI range of oxygen to be delivered to a patient?

15 Psi

What part of the anesthesia machine prevents excess buildup of pressure?

Pop off valve

When administering a breath to an anesthetized small patient, the pressure monometer should not exceed ______ cm H2O.

20

This scavenging system requires a vacuum and duct system, and typically includes a scavenger interface to regulate the vacuum.

Active scavenge

The absorbent granules in the CO2 absorbing canister typically have an _____ hour duration of use before needing to be replaced.

8-10 hours

The selection of a breathing circuit is based on the patient's weight. A non-rebreathing system is used for patients weighing more than 5 kg, while a rebreathing system is appropriate for patients weighing less than 5 kg.

FALSE

Mechanical dead space is the area where inhaled and exhaled gases mix, which can ultimately lead to increased end-tidal CO2 levels. What are some effects of increased end-tidal CO2?

-Respiratory acidosis

- Peripheral vasoconstriction/ vasodilation

- Increased intracranial pressures

The Murphy eye, located on an endotracheal tube, is a small hole situated just below the cuff. What is the primary function of the Murphy eye?

Minimizes the risk of asphyxiation in the event the end of the tube is blocked

You are evaluating a patient's level of consciousness (LOC) and find the patient in a sleeplike state, nonresponsive to verbal stimulus but arousable by painful stimulus. The patient is:

stuporous

You are evaluating a patient and notice the patient has a mildly decreased level of consciousness (LOC) and can be aroused with minimal difficulty. The patient is:

lethargic

Using the ASA physical status classification system, a patient who is anemic or moderately dehydrated would be classified as:

Class P3

Which is of the following is NOT a sign of fluid overload?

Hypotension

Which of the following is NOT a crystalloid solution?

Dextran

The fluid type most appropriate for replacing moderate losses due to dehydration would be:

isotonic crystalloids

What is a common equipment-related error that puts patients at risk for barotrauma?

closure of the pop-off valve

Mucous membranes are an indication of blood flow to peripheral tissues. A patient presents to the clinic with yellow-colored mucous membranes. This is an indication of what?

bilirubin accumulation

How much of the synthetic colloid will remain in the plasma 24 hours after administration?

30-60%

Which diagnostics are included in a big four?

BUN-GLUCOSE-PCV-TP

List the three drug classes used as preanesthetic medications

Anticholinergics, Tranquilizers, and Opioids

List the purposes for using preanesthetic medications:

-to calm or sedate

-Minimize adverse effects

-Reduce required dose of concurrently administered agents

-Produce smoother inductions and recoveries

-Decrease pain and discomfort

-Produce muscle relaxation

What are the reasons for needing to calm or sedate a patient before induction?

-Potential to have a very excited, frightened, or vicious patient

-Enhances comfort

-Sedation

-Reduces anxiety

-Simplifies patient restraint

-Keep personnel safe

What are the common routes of drug administration in anesthesia?

SC administration- slowest onset, longest duration

IM administration- somewhat faster onset and shorter duration than SC

IV administration- rapid onset, shorter duration than IM or SC

Anticholinergics such as Atropine and Glycopyrrolate are used to treat ____________

and ___________ salivary secretions?

Bradycardia; decrease

Which classes of tranquilizers can cause penile prolapse in equine?

Phenothiazines

The reversal Flumazenil is the reversal (antagonist) of which tranquilizer class?

Benzodiazepines

What are the TWO most used halogenated compounds?

Isoflurane and Sevoflurane

True or False. The rate of diffusion is controlled by the concentration gradient

between the alveolus and the bloodstream.

True

Isoflurane has a ________ partition coefficient and Sevoflurane has a __________

coefficient.

High; low

List four reasons the MAC might vary. What are the most common inhalant MACs

to know?

-Age

-Metabolic activity

-Body temperature

-Drugs/Adjuncts used

Isoflurane: 1.3%

Sevoflurane: 2.4%

Anesthesia is divided into 4 stages. Please list the 4 stages.

Stage 1: period of voluntary movement

Stage 2: period of involuntary movement

Stage 3: period of surgical anesthesia

Stage 4: period of anesthetic overdose

Patient monitoring is an important aspect of anesthesia. List the two reasons why

anesthesia monitoring is necessary

To keep the patient safe and to regulate anesthetic depth

Subjective monitoring consists of physical assessment. All are included in subjective

monitoring EXCEPT.

ECG

__________ is the pressure that remains in the arteries when the heart is in its

resting.

Diastolic

___________ evaluates how well a patient is ventilating.

Capnography

____________ in CO2 indicate hypoventilation (acidosis) and ___________ in CO2

indicate hyperventilation (alkalosis).

Increase; decrease

What is the normal % of oxygen a patient should have under anesthesia?

95%-100%

__________ measures the blood pH, and the dissolved oxygen and carbon dioxide

gas in the arterial blood.

Blood gas analysis

Physiological Pain

Protective sensation that usually occurs when there is tissue injury

Pathologic pain

Pain that is amplified and persistent; malfunction of or damage to the nervous system

Inflammatory pain

Pain that occurs at the site of tissue injury due to release of chemical mediators

Neuropathic pain

Pain that results from injury to the nervous system

Acute pain

Pain is immediate

Chronic pain

Pain with a long duration

Visceral pain

pain that originates from organs

Somatic pain

Pain that originates from the periphery

All are physiologic signs of pain under anesthesia EXCEPT:

a) Hypotension

c) Hypertension

d) Mydriasis

e) Tachycardia

What drug is ideal for treating windup pain?

Ketamine

This local technique blocks the maxilla rostral to the first premolar.

Infraorbital block

This local technique blocks the forelimb from the distal half of the humerus to the

toes.

Brachial plexus block

This local technique provides regional anesthesia to the lateral chest wall.

Intercostal block

This local technique blocks everything caudal to the last lumbar vertebrae.

Lumbosacral epidural

What are the 3 most common locations to perform an IM injection for

premedication in small animals?

Epaxials, Quadriceps, and

Semimembranosus/Semitendinosus

List four induction agents you can use for IV induction.

Propofol, Ketamine/Midazolam, Alfaxalone, and Etomidate

This induction requires placing the patient in a closed chamber or using a mask

infused with anesthetic gas

Mask/chamber induction

What is the max amount of air to use when inflating a cuff for cats

No more than 3 mls

List a complication of intubation when the tube is too long

Increase respiratory

effort which can lead to hypoventilation and hypoxia

What type of drug is Atropine?

Anticholinergic

After IV administration, this class of drug may induce significant peripheral vasoconstriction and reflex bradycardia.

alpha-2 adrenergic agonist

What are the drugs classified as tranquilizers?

-Alpha 2 adrenergic agonist

-Benzodiazepine

-Phenothiazines

True or False. Drugs such as Diazepam, Zolazepam, and Midazolam are classified as minor tranquilizers?

True

Which of the following drugs is an Alpha 2 Adrenergic Agonist?

Detomadine

True or False. Anticholinergics are used to treat tachycardia and increase salivary secretions.

False

True or False. Alpha 2 Adrenergic Agonist are metabolized in the liver and excreted in the urine.

True

_____________is used to reverse the effects of dexmedetomidine in dogs, cats, and exotic species.

Atipamezole

Commonly used opioids include:

Fentanyl, Hydromorphone, Oxymorphone, Morphine

Most opioids have a relatively short duration of action except _______________ and ________________.

Buprenorphine; butorphanol

Opioids cause mydriasis (dilation) in dogs and miosis (constriction) in cats.

FALSE

What type of opioid is Fentanyl?

mu agonist

A 5 year old male neutered schnauzer named Biscuit has presented to the CVM for a routine dental extraction with a grade 3 periodontal disease. What is the ASA status of this patient?

ASA 3

This stage of anesthesia is subdivided into 4 different planes of anesthesia based on eye movement, pupil size, and eyelid movement.

Stage III

This stage of anesthesia is known as the period of involuntary movement. Within this stage of anesthesia, the patient can go through an excitement stage and have involuntary reactions such as vocalizing, struggling, or paddling.

Stage II

This stage of anesthesia is known as the anesthetic overdose stage. Within this stage, the patient may experience a dramatic drop in heart rate and blood pressure.

Stage IV

______________is produced by the contraction of the left ventricle as it propels blood.

Systolic

_____________measures the percentage of oxygen bound to hemoglobin.

Pulse Oximetry

A ______ in CO2 can indicate hyperventilation (alkalosis) in a patient under anesthesia.

Decrease

This type of blood pressure monitoring gives a continuous reading of the blood pressure throughout the procedure and is more accurate.

Direct blood pressure

Blood gases are used to measure the blood pH, and the dissolved oxygen and carbon dioxide gas in the arterial blood. Which value is use as a invasive method of monitoring the CO2?

PACO2

The pathway of pain in the body is referred to as nociception with four main steps. During this step, signals are transmitted to the brain, where they are processed and recognized

Perception

The pathway of pain in the body is referred to as nociception with four main steps. During this step, signals are conducted to the spinal cord via the peripheral nerves

Transmission

Constant release of pain mediators can lead to other known conditions. One condition seen is when there is an increase in sensitivity to a painful stimulus, usually seen clinically as an exaggerated response to stimuli

Peripheral hypersensitivity

Regional/Local anesthetic blocks are important because they reduce the MAC of inhalant being used, lower the recovery time, and help avoid using general anesthesia in large animal patients such as equine and bovine. The retrobulbar block will block the orbit and optic nerve. When done correctly, the eye should look exophthalmic. True or False. This block can be used in most ophthalmology cases?

False

Regional/Local anesthetic blocks are important because they reduce the MAC of inhalant being used, lower the recovery time, and help avoid using general anesthesia in large animal patients such as equine and bovine. This block is used to block the perineum, rectum, and tail. It is the regional technique of choice with cats who are blocked.

Sacrococcygeal epidural

All are classified as agents that could be use for induction EXCEPT:

Acepromazine

Etomidate

Alfaxalone

Midazolam

There are many complications of intubation. One common complication is aspiration during the recovery period of anesthesia. Which complication is aspiration associated with?

Underinflation

True or False. Placement of the ECG electrodes does not matter as long as they cross the heart.

True