FRCS Study Guide 2026

The R classification describes completeness of surgical resection: R0 = complete resection with microscopically clear margins (curative intent achieved); R1 = microscopic residual tumour at margins; R2 = macroscopic residual tumour. R0 resection is the primary determinant of long-term cure in solid organ malignancies.

A competent adult's refusal of treatment is legally and ethically binding, even when it results in death. The surgeon must ensure the decision is informed, not subject to undue influence, and made with capacity. Detailed documentation, ethics consultation, and support for the patient and family are essential.

The retromuscular (Rives-Stoppa) technique, placing mesh posterior to the rectus muscle in the retromuscular plane, achieves the lowest recurrence rates for complex ventral hernias. The mesh is held in place by intra-abdominal pressure and avoids direct bowel contact, reducing adhesion risk.

The bicarbonate-carbonic acid (HCO3-/H2CO3) system is the principal extracellular buffer. It is an open system: CO2 is regulated by the lungs and HCO3- by the kidneys, giving it enormous buffering capacity. Although the phosphate system is important intracellularly and in renal tubular fluid, and haemoglobin is the main intracellular buffer of red blood cells, bicarbonate dominates extracellularly.

Factor VII has the shortest half-life of approximately 4–6 hours and is dependent on vitamin K and hepatic synthesis. The PT/INR, which is sensitive to Factor VII, is the most sensitive early indicator of hepatic synthetic failure and is incorporated into prognostic scoring (Child-Pugh, MELD, King's College Criteria).

Post-thyroidectomy hypocalcaemia results from inadvertent removal or devascularisation of the parathyroid glands during surgery, causing hypoparathyroidism. Symptoms include perioral and digital tingling (paraesthesiae), carpopedal spasm (Trousseau's sign), Chvostek's sign, and eventually tetany or seizures.