How to use these questions
MRCS Part B is an in-person OSCE-style examination with multiple short, timed stations. Stations commonly sample clinical examination, history taking, communication, procedural skills, applied anatomy and pathology, interpretation of investigations, and peri-operative or trauma decision-making. Candidates are judged on safe performance, a structured approach and clear communication under time pressure.
The following are single-best-answer practice drills for decisions that can arise in those station themes. They are not a description of the exam’s station format. For each one, choose the safest next step; then read the explanation and note the distractor that could cost you time or marks. Practise saying your reasoning aloud in a concise, ordered way.
A MySummaries practice question on a post-thyroidectomy airway emergency looks like this:
A patient develops increasing neck swelling, anxiety and stridor several hours after thyroidectomy. Oxygen saturation is falling. What is the most appropriate immediate action?
An expanding postoperative neck haematoma can rapidly obstruct the airway. Call for help and oxygen, but do not delay decompression while waiting for imaging or transfer: open the wound and evacuate the haematoma at the bedside, while the airway team prepares definitive airway management. A CT scan is the strongest distractor because it delays treatment of an immediate threat.
The pattern to retain is recognise the threat, call for help, act immediately, and continue definitive airway management. In an OSCE, verbalise those steps rather than giving only a diagnosis.
Emergency assessment and first actions
This drill tests recognition of a time-critical chest injury and the priority of treatment over imaging.
A patient after blunt chest trauma is severely breathless and hypotensive. The right side has markedly reduced breath sounds, with hyper-resonance and distended neck veins. What is the best next step?
The findings in an unstable patient are consistent with tension pneumothorax. Treat immediately with chest decompression, followed by a chest drain; do not wait for imaging. A portable radiograph may be useful in other circumstances, but here it risks delaying treatment of an immediately life-threatening problem.
In a station, state that you would use an ABCDE approach, call for senior and trauma-team assistance, and reassess after intervention. The distractor is not that imaging is never useful; it is that imaging must not delay treatment in this unstable presentation.
This question tests the first priority for acute limb ischaemia and the need for urgent specialist escalation.
A patient has sudden severe leg pain, pallor, a cold foot, paraesthesia and absent distal pulses. There is no known contraindication to anticoagulation. What is the best initial management?
This is acute limb ischaemia, requiring urgent vascular assessment. Start intravenous unfractionated heparin unless contraindicated, and escalate immediately to the vascular team; assess limb viability and arrange definitive investigation and treatment with them. Routine or next-day review is unsafe because delay may threaten the limb.
A useful spoken sequence is to identify the threatened limb, assess and document neurovascular findings, provide analgesia, check for contraindications to anticoagulation, and escalate urgently. Do not imply that anticoagulation replaces definitive vascular assessment.
This drill tests recognition of a spinal emergency and the appropriate urgent investigation.
A patient with acute back pain reports new urinary retention and numbness around the perineum. What is the most appropriate next step?
New urinary retention with perineal sensory change raises concern for cauda equina syndrome. Arrange urgent MRI and urgent spinal assessment; do not defer investigation to routine follow-up. Analgesia is appropriate, but it does not address the time-critical risk of neurological injury.
In an OSCE answer, name the red flags, explain the urgency to the patient, document the findings and escalate. Avoid promising a particular outcome before imaging and specialist review.
Consent, injury and practical judgement
This question tests decision-specific capacity and how to respond when a patient refuses recommended treatment.
A patient with a hand laceration understands your explanation that exploration is recommended to assess possible tendon injury. They can retain and weigh the information and communicate a clear refusal. What should you do?
Capacity is decision-specific. If the patient can understand, retain, use or weigh the relevant information and communicate a decision, their informed refusal must be respected. Clarify their understanding, explain material risks and alternatives, offer time or support if appropriate, and document the discussion. A relative cannot override the decision of an adult with capacity.
A clear station response covers the patient’s choice, the information given, any alternatives and the plan if they change their mind or develop concerning symptoms. Do not equate an unwise decision with lack of capacity.
This drill tests safe early management of an open fracture, rather than definitive operative treatment.
A haemodynamically stable patient has a contaminated open tibial fracture. The limb is perfused and there is no immediate threat to life. After the primary survey, what should be prioritised?
After the primary survey, give intravenous antibiotics promptly, provide analgesia and protect the wound and limb with appropriate sterile coverage and splintage while arranging urgent orthopaedic management. Repeated probing and emergency-department closure are inappropriate; antibiotics should not be delayed for cultures.
In practice, follow local open-fracture pathways and seek urgent orthopaedic input. In the station, mention distal neurovascular status before and after splintage, and avoid manipulating or probing the wound unnecessarily.
This question tests applied anatomy by linking a nerve lesion to a characteristic motor and sensory pattern.
After a fracture near the fibular neck, a patient has foot drop and reduced sensation over the dorsum of the foot. Which nerve is most likely injured?
The common peroneal nerve is vulnerable around the fibular neck. Injury can impair ankle dorsiflexion and eversion, causing foot drop, and affect sensation over much of the dorsum of the foot. The tibial nerve is the strongest distractor but chiefly supplies plantar flexion and plantar foot sensation.
For a real examination station, describe the relevant motor and sensory examination, compare sides, document the findings and consider associated injury. Do not infer the full extent of nerve damage from one finding alone.
Postoperative and wound complications
This drill tests a basic, reversible check before treating postoperative oliguria as a fluid deficit.
A postoperative patient has produced very little urine over the last hour. They are not distressed, and the catheter bag contains little urine. What is the best first check?
First assess the patient and check that the catheter and drainage system are patent, including the tubing and bag position. Then review observations, fluid balance, examination and relevant investigations, and escalate according to the findings. A fluid bolus may be appropriate if assessment supports hypovolaemia, but giving one reflexively can be harmful and misses a simple mechanical cause.
The question is not asking you to ignore shock or renal injury. It tests whether you check the patient and a potentially reversible cause before choosing treatment. Escalate promptly if the patient is unwell or oliguria persists.
This question tests immediate action when a postoperative wound has opened and bowel is exposed.
On the ward, a patient coughs and their abdominal wound opens, with bowel visible. They are haemodynamically stable. What is the best immediate action?
Protect the exposed bowel with sterile saline-moistened dressings, call the surgical team urgently, keep the patient nil by mouth and prepare for urgent operative assessment. Do not attempt bedside reduction or closure. Continue assessment and resuscitation, and monitor for deterioration.
A concise verbal answer should include help, protection of the viscera, nil by mouth, intravenous access and preparation for urgent review. Adapt the details to the patient’s observations and local emergency pathway.
Review the errors, not just the score
Use the explanations to identify a repeatable error: delaying treatment for a test, overlooking an immediate safety step, or failing to state escalation. In an OSCE, a correct decision also needs a clear structure. Start with the immediate risk, say what you will do, explain what you will reassess and state whom you will involve.
This final question tests immediate management of severe hyperkalaemia with ECG changes.
A patient with renal impairment has a markedly raised potassium concentration and ECG changes consistent with hyperkalaemia. What is the immediate treatment priority?
With ECG changes, intravenous calcium is given to stabilise the myocardium while measures to lower serum potassium are started urgently and the cause is addressed. Calcium does not itself lower potassium, so it must be accompanied by definitive potassium-lowering management. Waiting for a repeat result risks a dangerous delay when the clinical and ECG findings indicate an emergency.
A question set is most useful when it shows where performance is uneven, not just the total. A practice record might rank the candidate’s weaker areas like this:
If the same point is missed repeatedly, turn it into a short recall prompt and revisit it in a later session. For example, a remediation tray could surface this question after repeated errors:
You lost this mark twice: in a stable patient with an open tibial fracture, what should you do promptly before definitive operative management?
How MySummaries helps
Build a revision board from your own notes, slides or PDFs, then use it to practise retrieval and review weak areas. For MRCS Part B preparation, pair short decision questions with spoken practice: explain your structure, safety checks, reasoning and escalation as if addressing an examiner. Start with your material on MySummaries.