OK Vet Tech cheat sheet

Bioavailability (F) = (AUC oral / AUC IV) x 100; IV drugs are by definition 100% bioavailable.

First-pass hepatic metabolism reduces oral bioavailability; drugs with high first-pass effect (e.g., lidocaine, morphine) are given IV or parenterally.

Volume of distribution Vd = dose / plasma concentration; large Vd (>1 L/kg) indicates extensive tissue distribution and poor dialyzability.

Clearance CL = (dose x F) / AUC; half-life t1/2 = 0.693 x Vd / CL.

Drugs are weak acids or weak bases: acidic drugs (NSAIDs, barbiturates) are better absorbed in the acidic stomach; basic drugs in the small intestine.

Loading dose = (Vd x target concentration) / F; maintenance dose rate = CL x target concentration / F.

Controlled substances in the US are scheduled I–V under the DEA; Schedule II requires a separate order form and no refills.

Cytochrome P450 inducers (phenobarbital, rifampin) lower plasma levels of co-administered drugs; inhibitors (ketoconazole, cimetidine, erythromycin) raise them.

Do not mix incompatible drugs in the same syringe: penicillin with aminoglycosides, and calcium with ceftriaxone, form precipitates or inactive complexes.

Aseptic technique: surgical hand scrub lasts 3–5 minutes with chlorhexidine or povidone-iodine; sterile gown and gloves are donned without touching the outside of the gown.

Surgical gowns are sterile only from chest to waist and from cuffs to elbows; the back, shoulders, and below the waist are non-sterile.

Patient skin prep: clip hair, then scrub in concentric circles from the incision site outward using alternating chlorhexidine and alcohol or iodine solution; never return to the center.

Anesthesia circuit and endotracheal tube connectors must be checked for patency before draping; a patient's airway is never covered by the drape without a plan.

Surgical counts (sponges, needles, instruments) are performed before incision, before closure, and before the skin is closed; any discrepancy is reported to the surgeon immediately.

Suture selection: absorbable (polydioxanone, polyglactin 910) for internal tissues; non-absorbable (nylon, polypropylene) for skin; monofilament reduces infection risk versus braided.

Postoperative monitoring includes temperature, pulse, respiration, mucous membrane color, capillary refill, and pain score every 15 minutes until recovery.

Hypothermia prevention: warm IV fluids, forced-air blankets, and warmed table pads; core temperature below 37°C (98.6°F) impairs coagulation and drug metabolism.

Surgical drains (Penrose, Jackson-Pratt) are measured and recorded every shift; output greater than expected or a sudden change warrants veterinary notification.

Dental formula for the adult dog: 42 permanent teeth (I 3/3, C 1/1, P 4/4, M 2/3 per side); adult cat: 30 teeth (I 3/3, C 1/1, P 3/2, M 1/1).

Periodontal disease staging uses attachment loss and probing depth: Stage 1 gingivitis, Stage 2 <25% attachment loss, Stage 3 25–50%, Stage 4 >50%.

The most commonly affected tooth in dogs is the maxillary fourth premolar (carnassial) followed by the mandibular first molar; in cats, the mandibular first molar and maxillary fourth premolar.

Dental radiographs are required before extraction; two views (parallel and bisecting angle) are recommended for each tooth.

Feline odontoclastic resorptive lesions (FORLs) appear as defects at the cementoenamel junction; extraction or crown amputation with intentional root retention is performed.

Scaling and polishing must be followed by polishing to smooth enamel; fluoride varnish may be applied afterward to reduce sensitivity.

Local anesthesia for dental blocks: maxillary nerve block (0.1–0.2 mL), mandibular nerve block (0.1–0.2 mL), and infraorbital block for maxillary premolars.

Dental charts use the Modified Triadan system: 100s maxillary right, 200s maxillary left, 300s mandibular left, 400s mandibular right.

Anesthesia for dental procedures should include a cuffed endotracheal tube to prevent aspiration of debris and water; the cuff is inflated and checked before scaling.

Blood collection tubes: lavender (EDTA) for hematology; red (no additive) for serum chemistry; green (heparin) for plasma chemistry; blue (sodium citrate) for coagulation testing.

Order of draw: blood cultures, then light blue (citrate), red/gold (serum), green (heparin), lavender (EDTA), gray (oxalate/fluoride).

PCV is measured by centrifuging a microhematocrit tube; normal dog PCV 37–55%, cat 30–45%; total protein by refractometer, normal dog 5.5–7.5 g/dL.

Blood smear evaluation: scan at 10x for monolayer, then 40x and 100x oil for platelet estimate (approximately 1 platelet per 100x field x 15,000/µL).

Urinalysis: specific gravity by refractometer (dog 1.015–1.045, cat 1.035–1.060); dipstick pH, protein, glucose, ketones, bilirubin, blood, and sediment exam.

Fecal flotation with zinc sulfate or sugar solution concentrates nematode eggs; direct smear detects motile protozoa such as Giardia and Tritrichomonas.

Coagulation: prothrombin time (PT) evaluates extrinsic pathway (factors II, V, VII, X); activated partial thromboplastin time (aPTT) evaluates intrinsic pathway (VIII, IX, XI, XII).

Blood glucose meter readings may differ from laboratory values in dogs and cats; confirm hypoglycemia or hyperglycemia with a plasma chemistry analyzer.

Cytology: fine-needle aspirate smears are air-dried and stained with Diff-Quik or Wright's stain; evaluate cell type, nuclear size, and presence of bacteria.

Normal vital signs: dog temperature 38.0–39.2°C (100.5–102.5°F), heart rate 60–160 bpm, respiratory rate 10–30/min; cat 38.0–39.2°C, 140–220 bpm, 20–30/min.

Body condition score (BCS) 1–9: 4–5 is ideal; 1–3 underweight, 6–9 overweight; BCS is more reliable than body weight alone for nutritional assessment.

Fluid therapy: maintenance rate approximately 2–3 mL/kg/hr for dogs and cats; replace deficits over 6–24 hours plus ongoing losses.

IV catheter sites: cephalic, saphenous, and jugular veins; the jugular is avoided in patients with coagulopathy or when a chest bandage is needed.

Nutritional support: resting energy requirement (RER) = 70 x (body weight in kg)^0.75 kcal/day; illness energy requirement is often 1.0–1.3 x RER.

Isolation protocols: wear gloves and gown, use dedicated equipment, and disinfect with an EPA-registered product effective against the suspected pathogen (e.g., parvo requires a virucide).

Nursing care for recumbents: turn every 4 hours, provide soft bedding, perform passive range-of-motion exercises, and monitor for decubital ulcers.

Bandage changes: check for swelling, discharge, odor, and toe temperature; a wet or soiled bandage is changed immediately to prevent infection.

Pain and stress reduction: minimize handling, use pheromone sprays or calming music, and provide hiding places for feline patients.

Preanesthetic assessment includes physical exam, PCV/TP, blood glucose, BUN, and ECG in older or high-risk patients; ASA classification guides risk.

Anesthetic depth signs: palpebral reflex lost at surgical plane, jaw tone decreased, eye position rotated ventrally in dogs; cats may keep eyes central.

Isoflurane MAC in dogs is approximately 1.3%, sevoflurane approximately 2.3%; MAC is the concentration at which 50% of patients do not respond to surgical stimulus.

Endotracheal tube size: dogs 6–10 mm ID, cats 3.5–5.0 mm ID; cuff inflation should be just enough to seal the airway without tracheal trauma.

Anesthetic machine checks: verify oxygen supply, vaporizer function, soda lime color, and a leak test by occluding the Y-piece and squeezing the reservoir bag.

Capnography: end-tidal CO2 normal 35–45 mmHg; a sudden drop may indicate esophageal intubation, circuit disconnection, or cardiac arrest.

Pulse oximetry: SpO2 below 90% indicates hypoxemia; check probe placement and perfusion before treating.

Reversal agents: atipamezole reverses medetomidine/dexmedetomidine; naloxone reverses opioids; flumazenil reverses benzodiazepines.

Hypotension under anesthesia is MAP below 60 mmHg; treat with fluid bolus, reduce vaporizer setting, and consider vasopressors or inotropes.

Triage: assess airway, breathing, circulation (ABC), then disability and exposure; life-threatening hemorrhage and airway obstruction are addressed first.

Cardiopulmonary resuscitation (CPR): chest compressions 100–120/min, compression-to-ventilation ratio 30:2, and 2-minute cycles with rhythm checks.

Shock: give isotonic crystalloid bolus 20 mL/kg (dog) or 10–15 mL/kg (cat) over 15–20 minutes; reassess perfusion after each bolus.

Gastric dilatation-volvulus: decompress with a stomach tube or trocarization, then treat shock and prepare for surgery; do not delay decompression.

Parvovirus: supportive care includes IV fluids, antiemetics, antibiotics for secondary infection, and monitoring for sepsis and hypoglycemia.

Heatstroke: cool with room-temperature water and fans, avoid ice water, and monitor for DIC and hypoglycemia; target temperature 39.5°C (103°F).

Toxicities: induce emesis only if ingestion was recent and the patient is alert; never induce emesis with caustic or petroleum products.

Emergency drug doses: epinephrine 0.01 mg/kg IV, atropine 0.02–0.04 mg/kg IV, and diazepam 0.5 mg/kg IV for seizures.

Monitoring in ICU: record mentation, heart rate, respiratory rate, blood pressure, urine output (target 1–2 mL/kg/hr), and pain score every 1–4 hours.

Radiographic density: air is most radiolucent (black), then fat, soft tissue/fluid, bone, and metal is most radiopaque (white).

Thoracic radiographs use peak inspiration and two orthogonal views (right lateral and either VD or DV); cats and dyspneic dogs are often imaged on inspiration as tolerated.

Abdominal radiographs: a minimum of two views (lateral and VD) is required to localize organs and detect free gas or obstruction.

Roentgen signs of disease: size, shape, position, margination, and opacity of organs; compare with adjacent structures and prior films.

Ultrasound: higher-frequency transducers (7.5–12 MHz) provide better resolution for superficial structures; lower frequencies (2–5 MHz) penetrate deeper.

Ultrasound artifacts include acoustic shadowing (bone, stones), enhancement (fluid-filled cysts), and reverberation (gas).

Contrast studies: barium sulfate for GI tract, iodinated contrast for urinary and vascular studies; never give barium when perforation is suspected.

CT provides cross-sectional imaging and is preferred for brain, lung, and complex orthopedic evaluation; MRI is preferred for soft tissue and spinal cord.

Radiation safety: use collimation, lead aprons, thyroid shields, and dosimeters; personnel should stand at least 2 meters from the primary beam.

Pain pathways: transduction, transmission, modulation, and perception; multimodal analgesia targets multiple points in the pathway.

Acute pain scales: use the Glasgow Composite Measure Pain Scale (CMPS-SF) for dogs and the Feline Grimace Scale for cats to guide treatment.

NSAIDs inhibit cyclooxygenase (COX); COX-1 is constitutive (gastroprotection, platelet function), COX-2 is induced at sites of inflammation.

Do not combine NSAIDs with corticosteroids; the combination increases risk of gastrointestinal ulceration and renal injury.

Opioids: mu-agonists (morphine, hydromorphone, fentanyl) provide potent analgesia; buprenorphine is a partial mu-agonist with a ceiling effect.

Local anesthetics: lidocaine 2 mg/kg IV or bupivacaine 1–2 mg/kg for nerve blocks; bupivacaine is longer-acting (4–6 hours) than lidocaine (1–2 hours).

Constant rate infusion (CRI) calculations: dose (mg/kg/hr) x body weight (kg) / concentration (mg/mL) = mL/hr; verify units before administration.

Chronic pain management includes weight control, joint supplements, physical therapy, and NSAIDs with periodic renal and hepatic monitoring.

Assess pain by observing posture, facial expression, vocalization, mobility, and response to palpation; physiologic signs include tachycardia and tachypnea.

Informed consent: the client must be told the diagnosis, treatment options, risks, and costs before procedures; consent is documented in the medical record.

Veterinary-client-patient relationship (VCPR) is required for prescribing and dispensing medications; it requires recent examination and knowledge of the animal.

Controlled substance logs must record date, patient, drug, amount, and prescriber; discrepancies are investigated and reported.

Medical records are legal documents; entries should be timely, legible, objective, and include consent, treatments, and client communication.

Confidentiality: client and patient information is not disclosed without consent except as required by law or for public health.

Euthanasia: obtain informed consent, confirm patient identity, and use an appropriate technique (e.g., IV barbiturate overdose) with a veterinarian present.

OSHA and safety: use personal protective equipment, follow hazardous drug handling guidelines, and maintain sharps containers and spill kits.

Financial policies: provide written estimates before procedures, document deposits, and discuss payment options before treatment to reduce disputes.

Professional ethics: practice within the scope of training, refer when needed, avoid conflicts of interest, and report animal cruelty as required by state law.