Primary FRCA Physiology: What to Study and How
Physiology is one third of the Primary FRCA MCQ — 30 of 90 questions — and it is the subject where anaesthetic training helps most. Cardiovascular and respiratory physiology dominate, and the questions lean towards applied, mechanism-based reasoning rather than pure recall.
Key points
- 30 of 90 MCQ questions — equal weight with pharmacology and physics
- Cardiovascular and respiratory physiology carry the most marks
- Expect curves: oxygen-haemoglobin dissociation, Starling, pressure-volume loops
- Applied angle: physiology as it changes under anaesthesia
What the syllabus covers
The physiology third of the paper follows the RCoA syllabus across the major systems, with a consistent tilt towards the physiology that matters at the anaesthetic workplace.
- Cardiovascular: cardiac cycle, pressure-volume loops, control of cardiac output, Starling forces, blood pressure regulation
- Respiratory: lung volumes and capacities, gas exchange, V/Q matching, oxygen-haemoglobin dissociation, control of breathing
- Renal and fluids: glomerular filtration, tubular handling, acid-base balance, fluid compartments
- Nervous system: action potentials, neuromuscular transmission, cerebral blood flow and its regulation
- Blood, liver, endocrine and gastrointestinal physiology
- Applied physiology: responses to anaesthesia, positioning, one-lung ventilation, pregnancy and extremes of age
How the questions are pitched
Physiology questions reward candidates who can manipulate a relationship, not just recall it. Expect to interpret or predict the direction of a curve shift — what happens to the oxygen-haemoglobin dissociation curve in acidosis, or to cerebral blood flow as PaCO2 rises.
Numerical fluency helps: normal values for lung volumes, cardiac output, GFR and serum electrolytes are assumed knowledge, and several questions each diet turn on them.
How to revise physiology
Work system by system, starting with cardiovascular and respiratory — together they carry the largest share of the physiology marks. For each system, learn the core relationships as curves and equations you can reproduce from memory, then test with questions immediately.
Acid-base is its own mini-discipline inside the paper: practise systematic interpretation of arterial blood gases until the compensatory responses are automatic, because these marks are among the most predictable in the whole MCQ.
Free tutorials on this topic
- Oxygen transport and the dissociation curve — shifts, the Bohr effect and 2,3-DPG.
- The cardiac cycle and pressure-volume loops — loops, heart sounds and how they are examined.
- Adrenal cortex and medulla — cortisol, aldosterone and catecholamine physiology.
- Heat production and loss — thermoregulation and perioperative hypothermia.
- Sleep and consciousness — the physiology underpinning anaesthetic depth.
More Primary FRCA guides
- Primary FRCA Pass Mark: How It Is Set and What to Aim For
- Primary FRCA Pharmacology: What to Study and How
- Primary FRCA Physics and Clinical Measurement: What to Study and How
- Primary FRCA preparation guide — exam structure, timelines and a full revision strategy.
- See the Primary FRCA pass rate — published RCoA figures, first attempt versus all attempts, and trends between sittings.
- Primary FRCA FAQ — format, study time, marking and results.
- Primary FRCA question bank — what's inside and syllabus coverage.
- Free Primary FRCA revision notes — full tutorials, free to read.
Test your knowledge
Reading about the Primary FRCA only gets you so far. Put it into practice with exam-style questions across pharmacology, physiology and physics — three days of full access, no card required.
Last checked against RCoA guidance: 26 August 2026. Pass marks, pass rates and exam regulations for each diet are published by the Royal College of Anaesthetists — always confirm the current position on the official RCoA examinations pages.