Medical-Surgical Nursing
What to master
Medical-surgical content rewards pattern recognition across systems. Build a mental file for each: fluid and electrolyte balance (especially potassium, sodium, calcium, magnesium), heart failure and fluid overload, COPD and oxygen targets, diabetes and insulin, chronic kidney disease, liver disease, and the postoperative course.
Postoperative priorities: airway and sedation, then haemorrhage, then infection, then DVT/PE, then wound complications (dehiscence, evisceration). Know that a sudden rise in pain, tachycardia, and falling urine output after abdominal surgery suggests bleeding, not "normal pain."
Know the classic clusters: hypokalaemia (weakness, ileus, arrhythmia, U waves); hyperkalaemia (peaked T waves, wide QRS - a cardiac emergency); hypocalcaemia (tetany, Chvostek, Trousseau); fluid overload (crackles, JVD, weight gain, S3).
Traps in questions
- Digoxin and potassium. Hypokalaemia potentiates digoxin toxicity. A question offering "hold digoxin and notify the provider" for a patient with K 3.1 and nausea/visual changes is testing this link.
- Oxygen in COPD. The target is usually 88–92%; do not withhold oxygen from a hypoxic patient, but do not over-oxygenate either.
- Single abnormal values with a stable patient versus a value plus symptoms - symptoms drive urgency.
- Drains and tubes: never clamp a chest tube; never clamp a Foley without an order.
Worked example
A patient on digoxin reports nausea and "yellow-green halos." Apical pulse is 52/min, K is 3.1 mmol/L. Options: give the digoxin as ordered, give the digoxin with food, hold the digoxin and notify the provider, give potassium and recheck in 4 hours. Choose hold and notify: bradycardia plus visual disturbances plus hypokalaemia is a textbook toxicity picture.
Rule of thumb
When a medication's effect depends on an electrolyte, the electrolyte is the question.