Blood work you must know cold
BMP panel & electrolytes at a glance
Na, K, Cl, CO₂, BUN, creatinine, glucose — with the NCLEX memory tricks.
WBCs & the coagulation panel
Platelets 150k–400k · PTT 30–40 (heparin 46–70) · INR 0.9–1.2 (warfarin 2–3). Coag values gate every biopsy in this guide.
Electrolytes
Every electrolyte, high and low, on one page
K, Na, Cl, Mg, Ca, Phosphate — normal range, function, hyper- and hypo- signs and causes.
Serum potassium quick reference
<3.5 hypo · 3.5–5.0 normal · >5.0 hyper. Peaked T waves = hyperkalemia. Flat T + U wave = hypokalemia.
Acid–base / ABGs
ABG interpretation, worked through
Step 1 pH → Step 2 match pH to its partner (CO₂ = lungs, HCO₃ = kidneys) → Step 3 compensated or not.
Organ-specific markers
Amylase vs lipase — timing is the answer
Amylase rises 3–6 h, peaks 20–30 h, normalises in 2–3 days. Lipase follows amylase but stays up to 14 days. Late presentation → lipase is your marker.
Toxic ranges & antidotes
Therapeutic drug monitoring is a lab test too — and the antidote column is the part that gets tested.
Baselines & bedside signs
Normal vital sign ranges by age group
Newborn through post-partum. Baseline vitals are part of pre-test assessment for every procedure here.
Allen test — before you touch a radial artery
Confirms collateral ulnar flow. Colour returns in 5–7 seconds = pass. No return in 10 = do not stick.
Cardiac tracing
PQRST — what each wave actually means
P = atrial depolarisation · QRS = ventricular depolarisation · T = ventricular repolarisation. Everything on an ECG report refers back to this.
GI imaging & pathology
The nine abdominal regions and what lives in each
When a report says "epigastric" or "right iliac", this is the map. Pain location narrows the test list fast.
What the scope actually sees
Normal colonic mucosa (left) vs ulcerative colitis (right): loss of vascular pattern, friability, granularity.
Gastric vs duodenal ulcer
The classic EGD finding. Location matters: gastric ulcers get biopsied to rule out cancer.
Peritonitis
The thing you are watching for after a perforation. Rigid abdomen, rebound tenderness, fever, tachycardia.
A fistula, close up
An abnormal tract between two surfaces — a complication colonoscopy and manometry both look for.
Ileus vs small bowel obstruction
Bowel sounds are the tell: quiet/absent in ileus, high-pitched then absent in obstruction.
Obstruction on abdominal X-ray
Dilated loops with air-fluid levels.
Pyloric stenosis
Projectile vomiting in an infant. Upper GI study territory.
Airway devices — have these at the bedside
Endoscopy uses sedation. Oversedation → respiratory depression. Know what's on the crash cart.