Medical-Surgical Nursing
What this domain tests
Adult health items dominate any nursing entrance paper: ischaemic heart disease, heart failure, COPD and asthma, diabetes and its emergencies, chronic kidney disease, stroke, acid–base and electrolyte disorders, perioperative care, shock, and high-alert drugs (insulin, heparin, digoxin, potassium).
Core rules
- Acute MI: MONA-B - morphine, oxygen if hypoxaemic, nitrates (avoid in right ventricular infarct or sildenafil use), aspirin chewed. ST elevation on ECG with troponin rise confirms infarction; troponin rises within 3–6 hours.
- Heart failure: left-sided gives dyspnoea, orthopnoea, pulmonary oedema, frothy pink sputum; right-sided gives raised JVP, hepatomegaly, dependent oedema.
- Digoxin: therapeutic 0.5–2 ng/mL; toxicity is potentiated by hypokalaemia, hypomagnesaemia and hypercalcaemia. Early signs are anorexia, nausea, visual halos and bradycardia.
- Antidotes: heparin → protamine sulphate; warfarin → vitamin K; opioid → naloxone; paracetamol → N-acetylcysteine; benzodiazepine → flumazenil.
- Potassium: never give undiluted by IV push; maximum peripheral infusion roughly 10–20 mEq/hour with cardiac monitoring.
- Chest drain: keep below chest level, watch for bubbling (air leak) and swinging (patency).
Worked example
ABG: pH 7.28, PaCO₂ 55 mmHg, HCO₃⁻ 25 mEq/L. Step 1 - pH below 7.35 means acidosis. Step 2 - the deranged partner is CO₂, which is high, so it is respiratory. Step 3 - bicarbonate is normal, so there is no metabolic compensation. Answer: uncompensated respiratory acidosis, typical of COPD with CO₂ retention.
Traps that cost marks
- Calling a high-CO₂ acidosis "metabolic" because bicarbonate looks near-normal.
- Choosing nitroglycerin for an inferior MI with hypotension.
- Missing digoxin toxicity when the patient is also on furosemide and hypokalaemic.
- Forgetting that insulin onset/peak times decide when hypoglycaemia is most likely - regular insulin peaks in 2–4 hours.