IN Vet Tech key terms

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

Hepatic breakdown of an orally absorbed drug before it enters general circulation. It reduces oral bioavailability and explains why some drugs must be given parenterally or at higher oral doses.

The time required for plasma drug concentration to fall by half. It guides dosing interval selection; drugs with short half-lives need frequent dosing or sustained-release formulations to maintain therapeutic concentrations.

The ratio between a drug's toxic dose and its effective dose. A narrow index means the toxic and therapeutic ranges are close, so the patient needs careful dosing and monitoring, for example with digoxin or aminoglycosides.

Kidney damage caused by a drug or toxin. Common veterinary culprits include aminoglycosides, amphotericin B, and NSAIDs, especially in dehydrated patients; monitoring renal values and urine output helps detect it early.

A drug that reduces pain and inflammation by inhibiting cyclooxygenase enzymes and prostaglandin production. Veterinary NSAIDs are COX-2 selective where possible, but gastrointestinal and renal adverse effects still require monitoring.

The legally required interval between the last dose of a drug and slaughter or milk collection for human consumption. It applies to food-producing species and is set by regulatory authorities for each drug and tissue.

Prescribing or administering an approved drug in a manner not described on its label, such as a different dose, species, or route. It requires a valid veterinarian-client-patient relationship and careful record keeping, especially in food animals.

Practices that prevent microbial contamination of wounds, surgical sites, and sterile supplies. It includes hand hygiene, sterile gloves and drapes, and avoiding contact between sterile and nonsterile surfaces.

The timed, systematic cleaning of hands and forearms with an antiseptic detergent before surgery. The goal is to reduce resident and transient skin flora; it is followed by sterile gowning and gloving.

The area of a draped patient and instrument table that must remain free of microorganisms. Only sterile items and sterile-gloved personnel may contact it; any suspected contamination requires re-draping or replacement.

A method of ligating a vessel by placing three hemostatic forceps and cutting between two of them, leaving two ligatures on the patient side. It provides secure hemostasis during ovariohysterectomy and similar procedures.

The stopping of bleeding, achieved by pressure, ligature, electrosurgery, or topical agents. Maintaining hemostasis keeps the surgical field visible and reduces blood loss and postoperative complications.

The stalk of tissue containing the blood vessels that supply an organ, such as the ovarian pedicle or uterine stump. Secure ligation of the pedicle is critical to prevent hemorrhage after removal.

Inflammation and infection of the tissues supporting the teeth, progressing from gingivitis to loss of attachment and bone. It is the most common dental condition in dogs and cats and requires professional cleaning plus home care.

Removal of plaque and calculus from tooth surfaces using hand instruments or an ultrasonic scaler. It is performed under general anesthesia with airway protection, followed by polishing and irrigation.

The space between the gingival margin and the tooth surface. Pathologic deepening occurs when attachment is lost, and probing depth is measured to stage periodontal disease and plan treatment.

The way upper and lower teeth meet when the mouth closes. Abnormal occlusion, retained deciduous teeth, and malpositioned teeth can cause trauma and are assessed during every oral examination.

The percentage of blood volume occupied by red blood cells after centrifugation. It is a rapid bedside indicator of anemia, dehydration, or polycythemia and is often paired with total protein measurement.

The combined concentration of albumin and globulin in plasma or serum. Together with PCV, it helps distinguish dehydration from anemia and can suggest protein loss, inflammation, or marrow disease.

A thin film of blood spread on a slide and stained for microscopic examination. It allows assessment of cell morphology, platelet numbers, and the presence of parasites or atypical cells.

A measure of urea in blood that reflects renal excretion and hydration status. It rises with dehydration, reduced renal perfusion, or kidney disease and is interpreted alongside creatinine and urine specific gravity.

A muscle metabolism waste product filtered by the kidneys. It is less affected by hydration than BUN, making it a more specific marker of glomerular filtration and renal function.

The density of urine compared with water, reflecting the kidney's ability to concentrate or dilute. It helps distinguish prerenal from renal azotemia and assesses hydration and concentrating ability.

The rapid sorting of patients by urgency so that life-threatening problems are treated first. It uses a brief ABC assessment on arrival and is repeated as the patient's condition changes.

A state of inadequate tissue perfusion leading to cellular oxygen deprivation. Types include hypovolemic, distributive, cardiogenic, and obstructive; treatment targets the underlying cause plus fluid or vasopressor support.

Organized emergency measures to restore circulation and breathing in a patient in cardiac arrest. It combines chest compressions, ventilation, vascular access, and drugs such as epinephrine, guided by a team-based protocol.

Using two or more analgesic drugs or techniques with different mechanisms together to improve pain relief and reduce individual drug doses. Common combinations pair an opioid, an NSAID, and a local block.

Injection of an agent such as lidocaine or bupivacaine near a nerve or surgical site to prevent pain transmission. It provides preemptive analgesia and reduces the need for systemic anesthetic drugs.

The alveolar concentration of an inhaled anesthetic at which half of patients do not respond to a painful stimulus. It allows comparison of potency and guides vaporizer settings during anesthesia.

Continuous measurement of carbon dioxide in exhaled breath. The waveform confirms correct endotracheal tube placement, reflects ventilation, and can indicate return of circulation during resuscitation.

Placement of a cuffed tube through the mouth into the trachea to maintain an open airway and deliver oxygen or anesthetic gas. Correct placement is confirmed by capnography and chest auscultation.

The professional relationship in which the veterinarian has examined the animal and knows the client well enough to diagnose and treat responsibly. It is a legal prerequisite for prescribing medication and providing care.

The client's voluntary agreement to a procedure after receiving an explanation of benefits, risks, alternatives, and costs. Documented consent protects the patient, the client, and the practice.

The legal document of a patient's history, examination findings, treatments, and communications. Entries must be accurate, dated, and contemporaneous, because records support continuity of care and legal defense.

The rhythmic contractions of the rumen that mix ingesta and support fermentation. Reduced or absent motility signals ruminal stasis, often from acidosis, hypocalcemia, or obstruction, and is assessed by auscultation and percussion.

Evaluation of rumen contents for pH, protozoal activity, and color. A low pH suggests acidosis and poor protozoal motility suggests inactive flora, helping guide treatment of digestive disorders in cattle.