Introduction to Veterinary Anesthesia: Basics, Patient Prep, and Monitoring

What is the primary purpose of anesthesia in veterinary medicine?

To allow painful or stressful procedures to be performed safely.

What are the common uses of anesthesia in veterinary practice?

Surgery, dentistry, diagnostic imaging, wound care, grooming, and transport of wild animals.

What does the term 'anesthesia' mean?

It means 'without feeling' and involves loss of sensation, including pain perception.

What are the four main types of anesthesia?

Topical, local, regional, and general anesthesia.

What is topical anesthesia?

Anesthesia applied directly to a body surface or wound.

What is local anesthesia?

Anesthesia administered around or near a small target area.

What is regional anesthesia?

Anesthesia that desensitizes a larger region of the body.

What is general anesthesia?

A reversible state produced by anesthetic drugs that includes unconsciousness, immobility, and loss of sensation throughout the body.

What is surgical anesthesia?

A stage of general anesthesia that provides sufficient analgesia, muscle relaxation, and immobility for surgery.

What is the difference between sedation and tranquilization?

Sedation is drug-induced drowsiness where the patient may still be responsive, while tranquilization is a calming effect where the patient is less reactive.

Why is balanced anesthesia important?

It uses multiple drugs/techniques in smaller amounts to maximize benefits and minimize adverse effects.

What is the technician's role in anesthesia?

Veterinary technicians assist with machine preparation, drug administration, patient monitoring, and recordkeeping.

What factors make anesthesia high-risk?

Narrow therapeutic index, rapid cardiovascular changes, dose calculation errors, and poor recordkeeping.

What is included in the minimum patient database for anesthesia?

Patient history, signalment, physical examination findings, and preanesthetic diagnostic workup.

What does signalment include?

Species, breed, age, sex, and reproductive status.

What should be confirmed before anesthesia?

Correct patient, procedure, site/location, owner understanding, and consent.

What is required by California law regarding pre-anesthetic physical exams?

A physical exam must be performed by a licensed veterinarian within 12 hours prior to general anesthesia.

What are common terms used to describe the level of consciousness (LOC)?

BAR (bright, alert, responsive), QAR (quiet, alert, responsive), lethargic, obtunded, stuporous, and comatose.

What is the Body Condition Score (BCS)?

A numeric assessment of body condition on a 1-9 scale, where ideal scores are 4-5 for dogs and 5 for cats.

What are the common dehydration categories?

<5%, 5%, 8%, and 10%.

What does TPR stand for in veterinary medicine?

Temperature, pulse/heart rate, and respiratory rate.

What is the Heart Murmur Grade Scale?

A scale from 1 to 6 that describes the loudness of a heart murmur, with Grade 1 being very faint and Grade 6 being very loud.

What should students recognize in basic rhythm recognition?

Whether there is a P wave before every QRS, regular R-R intervals, consistent P-R intervals, and normal QRS complexes.

What is the normal color of mucous membranes?

Bubblegum pink, light pink, or pink with pigment.

What does pale mucous membrane color suggest?

Anemia, shock, vasoconstriction, or hypotension.

What does cyanotic mucous membrane color indicate?

Decreased oxygenated hemoglobin.

What does dusky blue mucous membrane color suggest?

Possible methemoglobinemia.

What could cherry red mucous membranes indicate?

Possible carbon monoxide exposure or severe inflammation.

What does brick red mucous membrane color suggest?

Vasodilation, sepsis, or heat stroke.

What does icteric mucous membrane color indicate?

Hyperbilirubinemia.

What is methemoglobinemia?

A condition where oxidized ferric form of iron is present in more than 1.5% of hemoglobin, leading to functional anemia.

What are the key components assessed in a respiratory assessment?

Respiratory rate, effort, pattern, lung sounds, cyanosis, and dyspnea.

What does the pupillary light reflex test assess?

Function of cranial nerves II and III and can help assess neurologic function.

What is the purpose of preanesthetic diagnostic workup?

To evaluate the patient's health status and identify any underlying conditions before anesthesia.

What are common components of a preanesthetic diagnostic workup?

CBC, chemistry panel, urinalysis, coagulation testing, ECG, radiographs, heartworm test, FeLV/FIV testing, echocardiogram.

What are signs of less than 5% dehydration?

Not detectable on physical exam, normal skin turgor.

What are signs of 5% dehydration?

Minimal decrease in skin turgor, dry mucous membranes, enophthalmos.

What are signs of 8% dehydration?

Moderate decrease in skin turgor.

What are signs of greater than 10% dehydration?

Severe loss of skin turgor, extremely dry mucous membranes, severe enophthalmos, hypotension, and depression.

What is the American Society of Anesthesiologists Physical Status Classification PS1?

Normal, healthy patient with minimal risk.

What does PS2 indicate in the ASA classification?

Low risk due to mild systemic disease.

What does PS3 indicate in the ASA classification?

Moderate risk due to severe systemic disease but not a constant threat to life.

What does PS4 indicate in the ASA classification?

High risk due to severe systemic disease with a constant threat to life.

What does PS5 indicate in the ASA classification?

Extreme or grave risk; dying patient not expected to survive without surgical intervention.

What is the fasting guideline for adult dogs and cats before anesthesia?

Food: 8-12 hours; Water: 2-4 hours.

What are the risks of not fasting before anesthesia?

Reflux, regurgitation, vomiting, esophagitis, stricture, aspiration pneumonia.

What are common starting fluid rates for healthy elective patients?

Dogs: 5 mL/kg/hr; Cats: 3 mL/kg/hr.

What are signs of overhydration or volume overload?

Hemodilution, nasal discharge, ocular discharge, chemosis, subcutaneous edema, increased lung sounds, increased respiratory rate, dyspnea.

What is the difference between crystalloids and colloids?

Crystalloids contain small solutes that move through capillary walls; colloids contain large molecules that stay intravascular longer.

What is the infusion rate terminology for IV fluids?

Prescribed rate = mL/kg/hr; Infusion rate = mL/hr for that patient; Delivery rate = gtt/mL from IV set package; Drip rate = gtt/min.

What should be prepared before induction of anesthesia?

Anesthetic machine, oxygen supply, breathing circuit, endotracheal tubes, monitoring equipment, emergency drugs/supplies, suction, heat support, IV fluids/pump, patient record.

What is the technician mindset for a good anesthetist?

Prepared, observant, accurate, calm, communicative, patient-centered, documentation-focused.