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

24 sample cards from the Generic Surgical Sciences and Critical Care deck

Sampled from the end of the deck, so these are different cards from the ones shown on the syllabus page.

1. 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.

2. 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).

3. 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.

4. 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).

5. 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).

6. 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).

7. 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.

8. 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.

9. 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.

10. 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.).

11. 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.

12. 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.

13. 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.

14. 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.

15. 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.

16. 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.

17. 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.

18. 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 $\sim 7\ \text{mm}$.

19. 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.

20. 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.

21. 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.

22. 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).

23. 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).

24. 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.

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