OMSB exam questions by profession

A patient with diabetic ketoacidosis is about to start a fixed-rate intravenous insulin infusion. Admission bloods show glucose 28 mmol/L, pH 7.10 and serum potassium 3.0 mmol/L. Which action is most appropriate?

1. AStart the insulin infusion at once and recheck potassium in 4 hours
2. BGive intravenous sodium bicarbonate before starting the insulin infusion
3. CDelay the insulin infusion and give intravenous potassium replacement first
4. DStart subcutaneous rapid-acting insulin instead of the intravenous infusion

A drug with a half-life of 8 hours is started as a regular maintenance dose without a loading dose. Approximately when will steady state be reached?

1. A8 hours
2. B16 hours
3. C32-40 hours
4. D96 hours

A psychologist trained in adult CBT is asked to treat a child with severe eating disorder. What is the most appropriate action?

1. ATreat using adult CBT protocols
2. BTreat while reading about the topic in parallel
3. CRefer on or obtain specialist supervision
4. DDecline and give no further help

A 34-year-old man had a perianal procedure in the lithotomy position under spinal anaesthesia with hyperbaric lidocaine. Eighteen hours later he reports aching pain in both buttocks radiating to the posterior thighs. Motor power, sensation, reflexes and bladder function are normal and he is afebrile. Which is the most appropriate management?

1. AEmergency MRI of the lumbar spine to exclude an epidural haematoma
2. BEpidural blood patch for presumed atypical post-dural puncture headache
3. CReassurance and NSAIDs, expecting resolution within days
4. DIntravenous antibiotics and lumbar puncture for suspected meningitis

A patient becomes pale, sweaty and loses consciousness briefly while seated for scaling. Pulse is slow but present. What is the first action?

1. ASit the patient fully upright
2. BLay the patient flat and raise the legs
3. CGive oral glucose immediately
4. DInject intramuscular adrenaline

A woman on an oxytocin infusion for induction has 6 contractions in 10 minutes and the CTG shows new late decelerations. What is the most appropriate immediate action?

1. AStop the oxytocin infusion and request an obstetric review
2. BIncrease the oxytocin rate to complete the first stage quickly
3. CHalve the oxytocin rate and repeat the CTG review in one hour
4. DContinue the infusion and perform fetal blood sampling first