MRCS Part B Revision · Applied surgical science and critical care
Sepsis — MRCS Part B Applied surgical science and critical care
By Dr Richard Miller, MBChB FRCS · Reviewed
Sepsis is an applied surgical science and critical care station. Three of the seventeen examined stations in the MRCS Part B OSCE fall in this area. These stations ask you to interpret data and manage a sick surgical patient: a chart, a blood gas, an imaging study or a deteriorating patient on the ward, and the physiology underneath the decision.
What you need to know for the Sepsis station
Sepsis
Systemic Inflammatory Response Syndrome
Development of SIRS is manifest by two or more of:
- Temperature > 38 C or < 36 C
- Tachycardia > 90 beats/min
- Tachypnoea > 20 breaths/min or PaCO2 < 4.25 kPa
- WBC >12 or<4
Systemic inflammatory response syndrome and multi-organ dysfunction syndrome (MODS)
Primary precipitating event → inflammatory response → SIRS → MODS → multi-organ failure (MOF)
Sepsis syndrome
This involves the progression from: SIRS → sepsis → severe sepsis → septic shock (refractory shock) → death
Sepsis: SIRS resulting from documented infection.
Severe sepsis: sepsis associated with evidence of end-organ dysfunction, hypoperfusion, hypotension.
Septic shock: severe sepsis with refractory hypotension (in spite of adequate volume resuscitation).
The Sepsis Six consists of three diagnostic and three therapeutic steps – all to be delivered within one hour of the initial diagnosis of sepsis:
• Deliver high-flow oxygen.
• Take blood cultures.
• Administer empiric intravenous antibiotics.
• Measure serum lactate and send full blood count.
• Start intravenous fluid resuscitation.
• Commence accurate urine output measurement.
What are you asked at the Sepsis station?
The station runs to 14 questions over nine minutes. These are the questions as they are put to you; the model answers are in the question bank.
- How would you manage this gentleman?
- What is sepsis six?
- What imaging would be indicated in this patient?
- Define sepsis
- Define Systemic Inflammatory Response Syndrome (SIRS)
- What are the common causes of SIRS?
- Define septic shock
- How could you differentiate septic shock from cardiogenic shock?
- Define multi organ dysfunction syndrome (MODS)
- How does the number of organs affected by MODS relate to mortality?
- What specifies of bacteria commonly cause intra-abdominal infections?
- What antibiotic regime would you start?
And 2 more at this station.
How is the applied surgical science and critical care station marked in MRCS Part B?
Each of these three stations is marked out of 20, split 12 marks for clinical knowledge and its application, 4 for clinical and technical skill and 4 for professionalism. No communication marks are available. The three cover critical care management, interpretation of clinical data, and interpretation of visual information.
FAQ
What does the Sepsis station ask?
It opens with "How would you manage this gentleman?" and runs to 14 questions over nine minutes. Each of these three stations is marked out of 20, split 12 marks for clinical knowledge and its application, 4 for clinical and technical skill and 4 for professionalism. No communication marks are available. The three cover critical care management, interpretation of clinical data, and interpretation of visual information.
What counts as applied surgical science in MRCS Part B?
Three of the seventeen examined stations: critical care management, interpretation of clinical data such as blood results and charts, and interpretation of visual information such as imaging and traces.
How is an applied science station marked?
Out of 20, with 12 marks for clinical knowledge and its application, 4 for clinical and technical skill and 4 for professionalism. Unlike the communication stations, none of the marks are for how you say it.
How much physiology do I need?
Enough to explain the decision you are making. The station rewards applying physiology to the patient in front of you rather than reciting it, so practise talking through why a number changes your management.
How many stations are in the MRCS Part B OSCE?
Seventeen examined stations of nine minutes each, with a minute to read the task before each one. Two preparation stations and at least one rest station bring the circuit to about twenty, and the exam takes about three and a half hours.
What is the pass mark for MRCS Part B?
There is no published pass mark. The cut score is set separately for Applied Knowledge and Applied Skills, for each circuit, by borderline regression. Published pass rates across the 2024/25 diets ranged from 51% to 66%.
Can I fail a station and still pass?
Yes. There is no rule about how many stations you may fail: the cut score applies to your total mark in each component, so a weak station costs the marks you lost on it and strong stations elsewhere can make them back. Applied Knowledge and Applied Skills are passed separately and must both be passed at the same sitting, so a strong anatomy performance cannot rescue a weak communication one.
Dr Richard Miller, MBChB FRCS
Station summaries are reviewed against the current intercollegiate MRCS syllabus and the published marking blueprint. Guidance changes between diets: check the royal colleges' own pages before relying on a date, a fee or a threshold.
Practise this station
The question bank carries the model answer to every question above, with the rest of the applied surgical science and critical care stations.
More applied surgical science and critical care stations