NV Vet Tech key terms

The fraction of an administered drug dose that reaches systemic circulation unchanged and is available to act at target tissues. Intravenous dosing is by definition 100 percent; oral and other routes are lower because of incomplete absorption and first-pass liver metabolism.

Metabolism of an orally absorbed drug by the liver and gut wall before it enters general circulation, reducing the amount that reaches tissues. It explains why some drugs given by mouth need much higher doses than when given intravenously.

The time required for the blood concentration of a drug to fall by half during elimination. It guides dosing intervals and tells you roughly how long a drug effect or withdrawal time will last after the last dose.

The ratio between a drug dose that causes toxicity and one that produces the desired effect. A narrow index means the effective and toxic doses are close together, so the patient needs careful monitoring and precise dosing, as with digoxin or aminoglycosides.

A compound that is pharmacologically inactive as given and must be converted by the body into the active form. An example is codeine, which the liver transforms into morphine to relieve pain.

A drug or molecule that binds a receptor and activates it, producing a biologic response. Full agonists trigger the maximal effect, while partial agonists produce a weaker response even when they occupy all available receptors.

A drug that binds a receptor without activating it, blocking the effects of agonists at that site. Competitive antagonists can be overcome by more agonist, while noncompetitive antagonists cannot.

Prescribing or administering an approved drug in a way not listed on its label, such as a different species, dose, or route. In the United States this is legal only under a valid veterinarian-client-patient relationship with specific conditions met.

The legally required interval between the last dose of a drug given to a food-producing animal and the slaughter of that animal or sale of its milk or eggs. It protects consumers from drug residues.

The professional relationship in which the veterinarian has examined the animal and assumed responsibility for its care, and the owner has agreed to follow recommendations. It is a legal prerequisite for prescribing medication and for extralabel use.

The process of explaining a procedure's purpose, risks, benefits, and alternatives so the owner can make a voluntary decision. Documenting the discussion protects the patient and the practice and is an ethical duty, not just a formality.

A set of practices that keep a surgical site and sterile equipment free of microorganisms. It includes sterile gowns and gloves, surgical hand scrub, sterile drapes, and avoiding contact between sterile and nonsterile items.

The area of a patient or table that is covered by sterile drapes and may be touched only by sterile instruments and sterile-gloved hands. Anything that contacts a nonsterile surface is considered contaminated and must be replaced.

Equipment that sterilizes instruments and supplies using pressurized steam at high temperature. Correct loading, wrapping, and monitoring with indicators or biologic spore tests confirm that sterilization actually occurred.

An infection that develops in or near a surgical incision within a defined period after the operation. Prevention depends on aseptic technique, clipping hair rather than shaving, proper skin preparation, and appropriate perioperative antibiotics when indicated.

Giving an antimicrobial before surgery to reduce the risk of infection, usually timed so peak tissue levels exist when the incision is made. It is indicated for contaminated or lengthy procedures, not routine clean surgery.

The lowest concentration of an antimicrobial that prevents visible growth of a specific bacterium in the laboratory. It helps predict whether a pathogen is likely to respond and guides drug and dose selection.

A laboratory test in which a sample is cultured to identify the infecting organism and then exposed to various antimicrobials to determine which ones inhibit its growth. Results guide targeted antibiotic therapy.

A panel that measures red blood cell, white blood cell, and platelet numbers plus hemoglobin and related indices. It screens for anemia, infection, inflammation, and bleeding disorders and is a core part of most diagnostic workups.

The percentage of blood volume occupied by red blood cells after centrifugation. It is a quick measure of hydration and red cell mass and helps detect anemia or hemoconcentration.

A thin layer of blood spread on a slide and stained for microscopic examination. It lets the technician assess red cell shape, platelet adequacy, and white cell morphology that automated counters may miss.

The evaluation done before anesthesia, including history, physical examination, and selected laboratory or imaging tests. Its purpose is to identify risks, choose an anesthetic protocol, and set monitoring plans for the individual patient.

A five-category scale that classifies a patient's overall health before anesthesia, from healthy to moribund. It helps standardize communication of risk and influences the choice of anesthetic drugs and monitoring intensity.

Continuous observation of vital parameters during anesthesia, including heart rate, rhythm, blood pressure, respiration, oxygen saturation, temperature, and depth of anesthesia. Early detection of trends allows intervention before a crisis develops.

Measurement of carbon dioxide in exhaled breath, displayed as a waveform. It confirms correct endotracheal tube placement, assesses ventilation, and can reveal low blood flow or airway obstruction.

A noninvasive method that estimates the percentage of hemoglobin saturated with oxygen using light absorption through tissue. It detects hypoxemia but becomes unreliable with poor perfusion, motion, or certain pigments.

A drug that counteracts the effects of another drug, often by competing at the same receptor. Examples include naloxone for opioids and atipamezole for alpha-2 agonists, used to speed recovery from anesthesia.

Using two or more analgesic drugs or techniques that act by different mechanisms to control pain. Combining them improves relief and allows lower doses of each, reducing side effects.

The nervous system's detection and transmission of a painful stimulus, from peripheral receptors through the spinal cord to the brain. Understanding this pathway explains where different analgesics act.

Injection of an agent such as lidocaine or bupivacaine near a nerve or incision to block pain transmission in that region. It provides targeted analgesia and can reduce the amount of general anesthetic needed.

The rapid sorting of patients by urgency so that life-threatening problems are treated first. It uses brief assessment of airway, breathing, circulation, and mental status to prioritize care in a busy emergency setting.

Emergency measures to restore circulation and breathing in a patient in cardiac arrest, including chest compressions, ventilation, and drugs. High-quality compressions with minimal interruptions are the foundation of success.

A life-threatening state in which oxygen delivery to tissues is inadequate for their needs, leading to cellular dysfunction. Types include hypovolemic, distributive, cardiogenic, and obstructive, and treatment depends on the cause.

Inflammation and destruction of the tissues supporting the teeth, caused by plaque bacteria. It is the most common dental problem in dogs and cats and progresses from gingivitis to loss of attachment and bone.

Removal of plaque and calculus from tooth surfaces using hand instruments or ultrasonic equipment, usually under general anesthesia. It is followed by polishing and often by dental radiographs to assess disease below the gumline.

Intraoral imaging used to evaluate tooth roots, bone, and structures hidden beneath the gums. It is essential for detecting disease that cannot be seen on visual examination and for planning extractions.

Placing the animal in a specific orientation for a radiographic view so anatomy is displayed accurately and consistently. Correct positioning, collimation, and labeling make images diagnostic and comparable over time.

The difference in density between adjacent structures on an image, which determines how well they can be distinguished. It depends on tissue composition and technique settings and is enhanced by contrast media.

Systematic evaluation of an animal's comfort using observation of posture, behavior, facial expression, and response to handling, plus validated scales. Because animals cannot report pain, regular scoring guides analgesic decisions.

Any harmful or unintended response to a drug given at a normal dose, ranging from mild vomiting to anaphylaxis. Recognizing and reporting these events supports patient safety and pharmacovigilance.