VTNE Mnemonics: 12 Memory Tricks for Vet Tech Students

Estimating dehydration and the fluid deficit

“Kilos times percent equals liters”

First estimate % dehydration from the exam: under 5% is not detectable (history only); about 5-6% gives tacky mucous membranes and a subtle skin-tent delay; 6-8% a clearly slow skin tent, dry membranes and possibly sunken eyes; 10-12% the skin stays tented, the eyes are sunken, CRT is prolonged and early shock signs appear; 12-15% is shock. Then deficit (L) = body weight (kg) x % dehydration as a decimal. A 20-kg dog at 8% needs 20 x 0.08 = 1.6 L to replace the deficit.

Use it when: Stems that give a weight and exam findings and ask for the replacement volume, or ask which findings match a given % dehydration.

Careful: The deficit is only one part of the fluid plan: daily maintenance and ongoing losses (vomiting, diarrhea, polyuria) are added on top. Skin turgor misleads in obese, emaciated and old patients. A patient in shock gets shock boluses first; you do not stop to calculate a dehydration deficit.

The three layers of a bandage

“Contact, Cushion, Cover”

1. ContactPrimary layer: the dressing that touches the wound (adherent or non-adherent, chosen for the stage of healing)
2. CushionSecondary layer: cast padding and conforming gauze that absorb exudate, pad and hold the dressing
3. CoverTertiary layer: the outer protective wrap, such as self-adhesive bandage, applied without stretching it

Use it when: Questions on which layer does what, the order they go on, or which material belongs in which layer.

Careful: Leave the tips of the two middle toes (digits 3 and 4) visible so swelling, coolness or the toes spreading apart can be spotted early. Most constriction injuries come from an outer layer pulled tight. A wet, soiled or slipped bandage, or strike-through of discharge, means it must be changed.

Rights of medication administration

“Please Don't Drop Rover's Tablets, then Document”

1. PRight patient: check the ID, cage card and species
2. DRight drug
3. DRight dose: recalculate from today's weight
4. RRight route
5. TRight time and frequency
6. DocumentRight documentation: record it immediately, including the controlled-drug log

Use it when: Stems about a medication error, a verbal order, or what to check before giving a drug.

Careful: Lists of 'rights' run from 5 to 10 (right reason, right response and so on), and the exam does not test the count, it tests the check. A drug given but not charted, or charted but not given, is an error either way.

Dose to volume

“Weigh, Multiply, Divide”

1. WeighBody weight in kg (pounds divided by 2.2)
2. Multiplykg x dose rate (mg/kg) = mg the patient needs
3. Dividemg divided by concentration (mg/mL) = mL to draw up

Use it when: Any 'how many mL' or 'how many tablets' item, and CRI or fluid-rate questions once you have the hourly dose.

Careful: Check units before you calculate: mcg versus mg (a factor of 1,000), mg/kg versus mg/lb, and a daily dose that must be split into BID or TID doses. If the answer comes out as 0.05 mL of a concentrated drug, the stem may be steering you to dilute it first.

Percent and ratio solutions

“Percent times ten equals mg per mL”

A percent solution is grams per 100 mL, so multiplying the percent by 10 gives mg/mL: 2% lidocaine = 20 mg/mL, 50% dextrose = 500 mg/mL, 0.9% NaCl = 9 mg/mL, 7.5% hypertonic saline = 75 mg/mL. Ratio strengths are grams per mL: 1:1,000 epinephrine = 1 g in 1,000 mL = 1 mg/mL, and 1:10,000 = 0.1 mg/mL.

Use it when: When a stem gives the concentration as a percent or ratio and asks for mL, and for dilution items (C1V1 = C2V2), such as making 5% dextrose from 50%.

Careful: Dilution stems trap the final volume: to make 500 mL of 5% dextrose you need 50 mL of 50% dextrose in a total of 500 mL, so you remove 50 mL from a 500-mL bag first. Adding 50 mL to a full bag gives 550 mL of about 4.5%.

DEA controlled-substance schedules

“Lower number, tighter lock”

1. C-INo accepted medical use (for example heroin); never stocked in practice
2. C-IIHighest abuse potential with a medical use: morphine, hydromorphone, fentanyl, methadone, plain pentobarbital; ordered on DEA Form 222
3. C-IIIKetamine, tiletamine-zolazepam, buprenorphine, anabolic steroids, pentobarbital-phenytoin euthanasia solution
4. C-IVButorphanol, diazepam, midazolam, phenobarbital, alfaxalone, tramadol
5. C-VLowest abuse potential, for example pregabalin

Use it when: Questions about which drug needs the stricter ordering, log or storage, or which schedule a familiar veterinary drug falls into.

Careful: Plain pentobarbital is C-II but the pentobarbital-phenytoin combination is C-III. Gabapentin is not federally controlled, but several states schedule it as C-V. Federal rules require controlled-drug records to be kept for at least 2 years and the drugs to be kept in a securely locked cabinet; many states require more.

Stages of anesthesia (Guedel)

“I Expect Smooth Operations”

1. IStage I, induction (voluntary movement): disorientation, possible struggling, reflexes present
2. EStage II, excitement (involuntary movement): paddling, vocalizing, irregular breathing, exaggerated reflexes
3. SStage III, surgical anesthesia, planes 1-4; plane 2 is the target for most surgery: eye rotated ventromedially, weak palpebral reflex, relaxed jaw
4. OStage IV, overdose: apnea, central fixed dilated pupils, cardiovascular collapse

Use it when: Stems that describe reflexes, eye position and breathing and ask how deep the patient is, or whether to deepen or lighten.

Careful: A central eye shows up twice: too light (with a brisk palpebral reflex) and dangerously deep (no palpebral, dilated pupil). Check reflexes and jaw tone to tell them apart. Ketamine breaks the pattern: the eyes stay open and central with reflexes present, so lubricate the corneas and judge depth on other signs. Modern premedication and IV induction move patients through stage II quickly.

Sudden desaturation or loss of ETCO2 in an intubated patient

“DOPE”

1. DDisplacement of the ET tube: extubated, in the esophagus, or advanced into one bronchus
2. OObstruction: kinked tube, mucus plug, herniated over-inflated cuff, neck sharply flexed
3. PPneumothorax or another cause of failed lung expansion
4. EEquipment failure: empty O2 tank or flowmeter off, circuit disconnected, stuck valve, exhausted CO2 absorbent

Use it when: Troubleshooting stems: SpO2 falls, the capnograph goes flat, or the reservoir bag stops moving.

Careful: DOPE comes from human airway care and lists causes, not the order of actions. Check the patient first: a flat capnogram can also mean cardiac arrest. Exhausted soda lime or a stuck unidirectional valve shows as a rising baseline (inspired) CO2, not a sudden drop.

White cell differential, most to least common

“Never Let Monkeys Eat Bananas”

1. NNeutrophils: the most numerous WBC in dogs, cats and horses
2. LLymphocytes
3. MMonocytes
4. EEosinophils
5. BBasophils: rare

Use it when: Differential counts, recognizing which cell is out of proportion, and reading a stress leukogram.

Careful: Ruminants are the big exception: cattle, sheep and goats normally have more lymphocytes than neutrophils, so a 'neutrophil-first' reading of a cow's count is wrong. Monocyte and eosinophil counts overlap, so their order can flip. A stress leukogram in a dog is mature neutrophilia, lymphopenia, eosinopenia and monocytosis.

Gram stain sequence

“Come In And Stain”

1. CCrystal violet: primary stain
2. IIodine: mordant that fixes the crystal violet
3. AAlcohol or acetone: decolorizer
4. SSafranin: red counterstain

Use it when: Questions on the order of reagents, which step went wrong, or why an organism stained purple or pink.

Careful: Purple = gram-positive: the thick peptidoglycan cell wall holds the crystal violet-iodine complex. Pink = gram-negative. Decolorizing too long turns gram-positive organisms pink, and old cultures can stain unevenly, so decolorization is the step to time carefully.

Modified Triadan tooth numbering

“Rule of 4 and 9”

1. 1-4Quadrants from the patient's upper right, clockwise: 1 = right maxilla, 2 = left maxilla, 3 = left mandible, 4 = right mandible (5-8 for deciduous teeth)
2. 4The canine tooth is always 04: 104, 204, 304, 404
3. 9The first molar is always 09: 109, 209, 309, 409

Use it when: Dental charting items and stems that name a tooth by number, such as 108 (the maxillary fourth premolar, the upper carnassial).

Careful: In cats, count from 04 and 09 because teeth are missing: the maxillary premolars are 106-108 (no 105) and the mandibular premolars are 307-308 (no 305 or 306). Dogs have 42 permanent teeth, cats 30. Quadrants are the patient's right and left, not yours.

Periodontal disease stages (AVDC)

“Under a quarter, up to half, over half”

AVDC stages are based on attachment loss measured by probing and radiographs. PD0: normal. PD1: gingivitis only, no attachment loss. PD2: early periodontitis, under 25% attachment loss. PD3: moderate periodontitis, 25-50% attachment loss. PD4: advanced periodontitis, more than 50% attachment loss.

Use it when: Charting questions and stems that give probing depths or radiographic bone loss and ask for the stage.

Careful: Stage each tooth, not the whole mouth, and never stage on calculus: heavy calculus with no attachment loss is at most PD1, while a clean-looking tooth can be PD4 on radiographs. Mobility (M0-M3) and furcation (F1-F3) are scored separately.