Fellowship of the Royal College of Surgeons (FRCS) Generic Surgical Sciences and Critical Care Syllabus

On cardiopulmonary exercise testing (CPET), which value predicts perioperative risk and what threshold is concerning?

The anaerobic threshold (AT); an AT $<11\ \text{mL O}_2/\text{kg/min}$ (and/or peak $\dot{V}O_2 < 15$) indicates increased perioperative cardiopulmonary risk.

State the Sepsis-3 definitions of sepsis and septic shock.

Sepsis: life-threatening organ dysfunction caused by a dysregulated host response to infection (an acute rise in SOFA score $\geq 2$). Septic shock: sepsis with persisting hypotension requiring vasopressors to keep MAP $\geq 65\ \text{mmHg}$ and lactate $>2\ \text{mmol/L}$ despite adequate fluid resuscitation.

What are the components of the qSOFA score and the abnormal thresholds?

Respiratory rate $\geq 22/\text{min}$, altered mentation (GCS $<15$), and systolic blood pressure $\leq 100\ \text{mmHg}$; $\geq 2$ of 3 suggests higher risk of poor outcome in suspected infection.

List the SIRS criteria.

$\geq 2$ of: temperature $>38^{\circ}\text{C}$ or $<36^{\circ}\text{C}$; heart rate $>90/\text{min}$; respiratory rate $>20/\text{min}$ or $PaCO_2 <4.3\ \text{kPa}$; white cell count $>12$ or $<4 \times 10^{9}/\text{L}$ (or $>10\%$ immature bands).

What are the key elements of the Surviving Sepsis 'Hour-1' bundle?

Measure lactate (remeasure if $>2$); obtain blood cultures before antibiotics; give broad-spectrum antibiotics; begin rapid crystalloid $30\ \text{mL/kg}$ for hypotension or lactate $\geq 4$; apply vasopressors if hypotensive during/after fluids to maintain MAP $\geq 65\ \text{mmHg}$.

What is the PaO2/FiO2 ratio and how does it grade ARDS (Berlin definition)?

The $PaO_2/FiO_2$ (P/F) ratio in mmHg with PEEP $\geq 5$: mild ARDS $200\text{--}300$, moderate $100\text{--}200$, severe $\leq 100$. (Divide kPa by $0.133$ to convert.)

Name a lung-protective ventilation strategy used in ARDS.

Low tidal volume ($\sim 6\ \text{mL/kg}$ ideal body weight), plateau pressure $<30\ \text{cmH}_2\text{O}$, appropriate PEEP, permissive hypercapnia, and prone positioning for severe ARDS.

What does the SOFA score assess?

Sequential Organ Failure Assessment scores six systems (0--4 each): respiration ($PaO_2/FiO_2$), coagulation (platelets), liver (bilirubin), cardiovascular (MAP/vasopressors), CNS (GCS), and renal (creatinine/urine output).

How are a patient's energy and protein requirements estimated in surgical nutrition?

Energy roughly $25\text{--}30\ \text{kcal/kg/day}$ and protein $1.0\text{--}1.5\ \text{g/kg/day}$ (higher in catabolic/critically ill patients); requirements may be calculated from basal needs via the Harris–Benedict equation adjusted by stress factors.

What is refeeding syndrome and its hallmark biochemical abnormality?

A potentially fatal fluid/electrolyte shift on reintroducing nutrition to a starved patient, driven by insulin surge. Hallmark is hypophosphataemia (also hypokalaemia, hypomagnesaemia and thiamine deficiency), risking arrhythmia and cardiac failure; correct electrolytes and give thiamine before slow feeding.

When is enteral nutrition preferred over parenteral, and why?

Enteral feeding is preferred whenever the gut is functioning ('if the gut works, use it') because it maintains mucosal integrity, reduces bacterial translocation, is cheaper and has fewer infective/metabolic complications. Parenteral nutrition is reserved for non-functioning or inaccessible GI tracts.

What are the components of the Wells score domains used for VTE risk, and what are the main pharmacological VTE prophylaxis options for surgical patients?

Wells assesses clinical probability of DVT/PE (e.g. cancer, immobility, prior VTE, signs of DVT, alternative diagnosis less likely). Surgical prophylaxis: mechanical (graduated compression stockings, intermittent pneumatic compression) plus pharmacological LMWH (or unfractionated heparin/DOACs) once bleeding risk allows.

Outline Virchow's triad for venous thrombosis.

1. Stasis of blood flow (immobility). 2. Endothelial/vessel wall injury. 3. Hypercoagulability (e.g. malignancy, surgery, thrombophilia).

What are the core elements of an Enhanced Recovery After Surgery (ERAS) programme?

Preoperative: counselling, carbohydrate loading, avoidance of prolonged fasting/bowel prep. Intraoperative: minimal access surgery, opioid-sparing/multimodal analgesia, goal-directed fluids, normothermia, avoiding drains/NG tubes. Postoperative: early mobilisation, early oral feeding, early catheter/line removal.

What is multimodal analgesia and the WHO analgesic ladder concept in postoperative pain?

Multimodal analgesia combines agents with different mechanisms (paracetamol, NSAIDs, opioids, local anaesthetic/regional blocks, adjuncts) to maximise effect and minimise opioid dose/side effects. The WHO ladder steps from non-opioids to weak opioids to strong opioids with adjuvants as pain severity increases.

List five evidence-based measures to reduce surgical site infection (SSI).

Antibiotic prophylaxis within 60 min of incision; appropriate skin antisepsis (e.g. chlorhexidine in alcohol); avoid shaving (use clippers if needed); maintain normothermia and normoglycaemia; supplemental oxygenation; and meticulous aseptic technique. NICE also recommends not removing hair routinely.

How are surgical wounds classified by contamination (CDC), with example SSI risks?

Clean (e.g. hernia, $\sim 1\text{--}2\%$); clean-contaminated (controlled entry into viscus, e.g. elective bowel, $\sim 5\text{--}10\%$); contaminated (gross spillage/acute inflammation, $\sim 15\text{--}20\%$); dirty (established infection/perforation, $>25\%$).

Name four common healthcare-associated infections and a key prevention measure for each.

Catheter-associated UTI (avoid/remove catheters early); central line-associated bloodstream infection (insertion bundle, sterile technique); ventilator-associated pneumonia (head elevation, sedation holds); Clostridioides difficile (antimicrobial stewardship, hand washing with soap, isolation).

What are the '4 Cs' antibiotics most associated with Clostridioides difficile infection?

Ciprofloxacin (fluoroquinolones), Clindamycin, Co-amoxiclav, and Cephalosporins. First-line treatment is oral vancomycin (or fidaxomicin).

Define the principles of antimicrobial stewardship (the 'Start Smart, Then Focus' approach).

Use antibiotics only when indicated; take cultures before starting; choose narrowest effective spectrum per local guidelines; document indication, dose and duration; then review at 48--72 h to stop, switch IV-to-oral, de-escalate, or continue with a clear plan.

Differentiate bactericidal from bacteriostatic antibiotics with examples, and define concentration- vs time-dependent killing.

Bactericidal kill bacteria (e.g. $\beta$-lactams, aminoglycosides, vancomycin); bacteriostatic inhibit growth (e.g. macrolides, tetracyclines, trimethoprim). Concentration-dependent killing (aminoglycosides) depends on peak/MIC; time-dependent killing ($\beta$-lactams) depends on time above MIC.

What is the LRINEC score used for and what does it predict?

The Laboratory Risk Indicator for Necrotising Fasciitis score (using CRP, WCC, haemoglobin, sodium, creatinine, glucose) stratifies the likelihood of necrotising soft tissue infection; a score $\geq 6$ raises suspicion and $\geq 8$ indicates high risk.

How are necrotising soft tissue infections classified microbiologically, and what is the definitive treatment?

Type I: polymicrobial (mixed aerobes/anaerobes, often diabetics). Type II: monomicrobial (Group A $\beta$-haemolytic Streptococcus $\pm$ Staph). Type III: clostridial gas gangrene or marine Vibrio. Treatment is urgent aggressive surgical debridement plus broad-spectrum antibiotics (with clindamycin for toxin suppression) and resuscitation.

Differentiate sterilisation from disinfection and decontamination.

Decontamination is the general process (cleaning, then disinfection or sterilisation) rendering items safe to handle. Disinfection reduces viable microorganisms but may not kill all spores. Sterilisation destroys all microorganisms including bacterial spores.

List common methods of instrument sterilisation and a typical autoclave cycle.

Steam autoclave (moist heat under pressure, e.g. $134^{\circ}\text{C}$ at $\sim 2.2\ \text{bar}$ for $\sim 3$ min, or $121^{\circ}\text{C}$ for $15$ min), ethylene oxide gas (heat-sensitive items), low-temperature hydrogen peroxide gas plasma, and gamma irradiation (industrial single-use items).

What is the Spaulding classification of instrument decontamination requirements?

Critical items (enter sterile tissue/vascular system, e.g. surgical instruments) require sterilisation. Semi-critical items (contact mucous membranes, e.g. endoscopes) require high-level disinfection. Non-critical items (intact skin contact, e.g. BP cuffs) require low-level disinfection/cleaning.

Rank the transmission risk of HBV, HCV and HIV after a percutaneous needlestick from a positive source.

Hepatitis B highest at $\sim 30\%$ (up to $\sim 1$ in 3 if e-antigen positive); Hepatitis C $\sim 3\%$ ($\sim 1$ in 30); HIV lowest at $\sim 0.3\%$ ($\sim 1$ in 300).

What are the immediate steps and prophylaxis after an occupational sharps injury from an unknown/high-risk source?

Encourage bleeding, wash with soap and water, do not suck; report and risk-assess; take baseline bloods. Offer HIV post-exposure prophylaxis (antiretrovirals, ideally $<1$ h, within 72 h); give hepatitis B vaccine/immunoglobulin per status; arrange HCV follow-up testing (no vaccine/PEP for HCV).

Define the hallmarks of cancer and explain the difference between an oncogene and a tumour suppressor gene.

Hallmarks include sustained proliferative signalling, evading growth suppressors, resisting apoptosis, replicative immortality, angiogenesis, invasion/metastasis, plus reprogrammed metabolism and immune evasion. Oncogenes (e.g. RAS, MYC) drive cancer when activated (gain-of-function, dominant); tumour suppressors (e.g. p53, RB) normally restrain growth and require loss of both alleles (Knudson 'two-hit', recessive).

Distinguish initiation, promotion and progression in chemical carcinogenesis.

Initiation: irreversible DNA mutation by a carcinogen. Promotion: reversible clonal expansion of initiated cells under promoter stimulation. Progression: accumulation of further mutations giving malignant, invasive and metastatic phenotype with genetic instability.

Define R0, R1 and R2 resection margins in surgical oncology.

R0: complete resection, microscopically negative (clear) margins. R1: macroscopically complete but microscopically positive margin (tumour at the cut edge). R2: macroscopic residual tumour left behind.

What is the difference between neoadjuvant and adjuvant therapy?

Neoadjuvant therapy is given before the primary (surgical) treatment to downstage/shrink the tumour and improve resectability. Adjuvant therapy is given after primary treatment to eradicate micrometastatic residual disease and reduce recurrence.

What is the role and core membership of an oncology multidisciplinary team (MDT)?

The MDT coordinates evidence-based, individualised cancer care and staging decisions. Core members: surgeon, oncologist (medical/clinical), radiologist, histopathologist, specialist nurse, and MDT coordinator, with allied input (palliative care, dietitian, etc.).

Name the criteria a screening programme should satisfy (Wilson–Jungner principles).

The condition is an important health problem with a recognisable latent/early stage and understood natural history; there is a suitable, acceptable, safe test; an accepted, effective treatment exists; facilities for diagnosis and treatment are available; screening is cost-effective and a continuous process. Examples: breast, cervical, bowel (FIT) and AAA screening.

Define sensitivity, specificity, PPV and NPV for a screening test.

$\text{Sensitivity} = \frac{TP}{TP+FN}$ (detects disease); $\text{Specificity} = \frac{TN}{TN+FP}$ (excludes disease); $\text{PPV} = \frac{TP}{TP+FP}$; $\text{NPV} = \frac{TN}{TN+FN}$. PPV and NPV vary with disease prevalence.

What is the role of palliative surgery, and name the principles of good end-of-life care.

Palliative surgery aims to relieve symptoms (e.g. bypass for obstruction, stenting, stoma, fixation of pathological fracture, bleeding control) rather than cure, balancing benefit against operative burden. End-of-life care principles: symptom control, honest communication, advance care planning/ceilings of treatment, holistic and family-centred support, and dignity.

Compare the basic physics and main uses of CT versus MRI.

CT uses ionising X-rays with Hounsfield-unit attenuation, giving fast, high-resolution bone/lung/acute-haemorrhage imaging. MRI uses no ionising radiation (proton relaxation in a magnetic field), giving superior soft-tissue contrast (T1 vs T2 weighting) for brain, spine, pelvis and liver lesions, but is slower and contraindicated with certain implants.

What are the Hounsfield unit reference values for water, air, fat and bone on CT?

Water $= 0\ \text{HU}$ (by definition), air $\approx -1000\ \text{HU}$, fat $\approx -50\text{ to }-100\ \text{HU}$, soft tissue $\approx +20\text{ to }+60\ \text{HU}$, and dense cortical bone $\approx +1000\ \text{HU}$ or more.

Give four examples of interventional radiology procedures relevant to surgery.

Image-guided drainage of abscesses/collections; angiographic embolisation for haemorrhage (e.g. GI bleed, trauma, post-partum); angioplasty/stenting of stenoses; transjugular intrahepatic portosystemic shunt (TIPSS); biliary/nephrostomy drainage; and IVC filter insertion.

Explain how monopolar and bipolar electrosurgery (diathermy) differ.

In monopolar diathermy current passes from the active electrode through the patient to a return plate, producing cutting (continuous low-voltage) or coagulation (pulsed high-voltage) — risk of burns/channelling, avoid on appendages. In bipolar, current passes only between the two limbs of forceps, confining the effect, with no patient plate and safer near end-arteries.

How do ultrasonic (harmonic) and advanced bipolar (vessel-sealing) energy devices work?

Ultrasonic devices vibrate a blade at $\sim 55{,}000\ \text{Hz}$, generating frictional heat that cuts and coagulates at lower temperatures with minimal lateral spread. Advanced bipolar/vessel-sealing devices apply controlled bipolar energy plus pressure to denature collagen/elastin and seal vessels up to $\sim 7\ \text{mm}$.

State the physiological effects of the CO2 pneumoperitoneum used in laparoscopy.

Insufflation pressure (typically $12\text{--}15\ \text{mmHg}$) raises intra-abdominal pressure reducing venous return and splinting the diaphragm; $\ce{CO2}$ absorption causes hypercarbia and respiratory acidosis; effects include reduced cardiac output, raised systemic vascular resistance, and risk of $\ce{CO2}$ embolism, vagal bradycardia and subcutaneous emphysema.

List the advantages and limitations of minimal access (laparoscopic) surgery.

Advantages: smaller incisions, less pain, faster recovery, shorter stay, fewer wound complications, better cosmesis. Limitations: loss of tactile feedback, two-dimensional view (in standard laparoscopy), restricted instrument movement, longer operative time/learning curve, and pneumoperitoneum-related physiological effects.

What advantages does robotic surgery offer over conventional laparoscopy?

Three-dimensional magnified vision, wristed instruments with extra degrees of freedom (EndoWrist), tremor filtration, motion scaling, and improved ergonomics — facilitating fine dissection and suturing in confined spaces (e.g. pelvis); offset by high cost, lack of haptic feedback and setup time.

Give the formula for cardiac output and mean arterial pressure used in haemodynamic assessment.

$CO = HR \times SV$ (stroke volume). Mean arterial pressure $MAP = DBP + \frac{1}{3}(SBP - DBP)$, and $MAP = CO \times SVR$ (rearranged to estimate systemic vascular resistance).

What are the indications for renal replacement therapy in the surgical ICU (AEIOU)?

Acidosis (refractory metabolic), Electrolyte disturbance (refractory hyperkalaemia), Intoxication (dialysable toxins), Overload (refractory fluid overload/pulmonary oedema), and Uraemia (symptomatic, e.g. pericarditis/encephalopathy).

What is base excess and how is it interpreted?

Base excess is the amount of acid or base (in mmol/L) needed to titrate 1 L of blood to pH $7.40$ at $PaCO_2$ $5.3\ \text{kPa}$ and $37^{\circ}\text{C}$. Normal $\pm 2\ \text{mmol/L}$; a markedly negative base excess ($< -2$) indicates metabolic acidosis, positive ($> +2$) indicates metabolic alkalosis.