Interlude exam 2 answers

INTERLUDE 2 ANSWERS

OK, answers below. Again, the invitation is to self mark. A couple of the questions are a b it left field - we know that! - but we have done so for a reason. See how you go - send in any major questions.

QUESTION 1.

A 21 year old male presents with the ambulance as a resuscitation call. Your team is assembled in resus, waiting. He has a history of asthma requiring ICU admission. On arrival to the ED he has a chest silent to auscultation, with the following vital signs:

HR 132 /min
RR 45 /min
O2 sats 90% 15L O2 NRB
BP 110/80 mmHg
GCS 15

i. (6 marks)

Describe your immediate management.

Immediate continuous nebulized salbutamol
Atrovent nebs 500mcg x 3 in the first hour
IV prednisone 200mg or equivalent
20mmol IV MgSO4 over 20/mins
IV salbutamol infusion 5mcg/min titrated, or IV adrenaline infusion 2mcg/min titrated
Start NIV CPAP 5cm H20 100% if non responsive

I mark for each.

Note, this patient has life threatening asthma, and candidates should demonstrate knowledge of this by treating them as such.

ii. (12 marks)

Despite your measures above, the patient deteriorates and is successfully intubated. Describe your ventilation strategy, including 2 underlying principles.

Principles:
Avoid dynamic hyperinflation
Permissive hypocapnoea to facilitate oxygenation

Ventilator settings:

TV 6ml/kg
RR 8-10, 100% oxygen
I:E 1:4
Measure autopeep with expiratory hold and set PEEP to 60-80% of autopeep
Titrate resp rate and inspiratory pressure to plateau pressure
- >25cm H20 reduce rate and pressure
- <25cm H20 increase rate and pressure

1 mark for each principle

1 mark
1marks
1 mark

3 marks

2 marks

1 mark
1 mark

Comment - to some degree this is an unfair question. It's quite nebulous, and worth a large number of marks. That said, the principles of ventilating a critically ill asthmatic are absolutely fair game, and so we have included this question here to make sure candidates will have thought of this at least once in the course!

QUESTION 2.

A 4 year old child presents with his parents. He has a fever, and has been feeling lethargic and nauseous for 10 days. He has no medical history of note.

A set of vital signs is taken:

HR 140 /min
RR 50 /min
O2 sats 95% on RA
BP 90/71 mmHg
GCS 15

i. (5 marks)

A full blood count is taken as part of the work up and the results are shown at 2 of the supplementary clinical information book. Describe and interpret the results and give a likely diagnosis

Must include:

Normocyctic anaemia
Leucopaenia
Thrombocytopaenia
Blasts present

Likely new diagnosis of acute leukaemia

1 mark each

1 mark for diagnosis

ii. (2 marks)

During your consultation with the patient’s mother she tells you this is the patient’s 4th visit to the ED this week. When questioned it she denies ever having been seen by a consultant or registrar. Outline your next 2 actions.

Must include the elements of:

1. Record and register the complaint for investigation
2. Refer the patient for admission under paediatrics/haematology

1 mark for each element

Comment - when answering questions like this, the key for candidates is to make sure that two key areas are included:
1. The welfare/safe disposition of the patient
2. Some elements of quality improvement.

Every question will look slightly different, but this is again just the application of the first parts of a generic admin answer in the context of a specific question.

iii. (4 marks)

Your Director asks you to investigate the complaint after the patient has been admitted. Outline the steps you would take.

Must include the elements of:

1. Review the medical record
2. Interview the staff concerned in the prior presentations
3. Summarise the important findings and report back to the Director
4. Outline areas to improve and institute a quality cycle

1 mark for each element

Again, this is a reasonably generic admin answer, just modified to suit the context of the question.

iv (2 marks)

Briefly outline 2 steps you could take in order to enact your quality improvement.

Anything reasonable such as:

Staff education via M+M
Develop policy of senior review for representations
Improve orientation manual to outline expectations of junior doctors

1 mark for each element.

QUESTION 3.

A 16 year old boy presents to you after an episode of syncope during a soccer game. His blood pressure at triage is recorded as 96/54.

i. (5 marks)
An ECG is taken when he is moved into the acute area. It is shown at page 3 of the supplementary information booklet. Describe and interpret the ECG.

1. Wide complex tachycardia rate approximately 142
2. Leftward axis
3. AV dissociation
4. Concordant chest leads

Likely VT

1 mark for each point and the diagnosis.

ii. (9 marks)
Give 2 options for the emergent management of this rhythm and a pro and con of each.

OPTION

ELECTRICAL CARDIOVERSION

CHEMICAL CARDIOVERSION

PRO

applies for all arrythmias
highest success rate

does not require sedation

CON

requires anaesthetic

lower success rate
dangerous if there is an accessory pathway

Comment: this is a pretty standard question that candidates should be able to answer. Note that the pros and cons are effectively just swapped between the two options.

iii. (7 marks)
The patient’s ECG post reversion is shown on page 4 of the supplementary clinical information booklet. Describe and interpret it.

Must include:

Rate 72
Sinus rhythm
Right axis deviation
T wave inversion inferior and praecordial leads
Epsilon wave seen

Diagnosis – arrythmogenic right ventricular dysplasia

1 mark for each descriptor

2 marks for diagnosis.

Comment: ARVD is a pattern recognition ECG that candidates must know.

QUESTION 4.

An 18 year old girl presents with her parents. She has a history of anorexia nervosa and has been refusing to eat for the last 2 weeks.

i.(6 marks)
List 6 investigations will you undertake in this patient and give a reason for each

BSL – hypoglycaemia
ECG – conduction changes (electrolytes)
FBC – anaemia
UEC – renal failure and electrolyte levels
bHCG – exclude pregnancy
VBG – starvation ketoacidosis

1 mark for each point accompanied by a reason.

ii. (9 marks)
Outline criteria that you would use to admit this patient to an inpatient medical unit rather than an eating disorders (mental health) unit.

Indications for admission to a medical unit rather than mental health unit include:

Hypotension (SBP <80mmHg) or postural drop >15mmHg
Bradycardia <40bpm
Hypothermia <35.5 or fever >38
Any ECG abnormality
Hypoglycaemia (<3mmol/L)
Electrolyte abnormalities
Renal Failure
Neutropaenia
Transaminitis (ALT/AST >500IU/L)

1 mark for each criteria.

Comment: this is a highly specific list, but based on first principles candidates should be able to work through and score a significant number of marks (ie by putting down common sense items!).

iii. (3 marks)
The patient’s VBG is shown at page 5 of the supplementary examination booklet. Describe the acid base balances present.

RAGMA
Metabolic alkalosis
Respiratory compensation

1 mark each

Comment: candidates should be clued into the triple disturbance present by the fact that there are three marks available for this question.

iv. (2marks)

Give 2 calculations to support your results.

ANION GAP 35
DELTA RATIO 2.3

1 mark each

Comment: these should be standard calculations for candidates by now.

QUESTION 5. (Note, continues into q6).

A 30 year old man presents via ambulance after a prolonged entrapment in an MVA. He has injuries to his head, chest and abdomen, and has been intubated by the prehospital team.

On arrival his vital signs are as follows:

HR 140 /min
RR 16 /min (ventilated)
O2 sats 97% on 100% O2
BP 90/71 mmHg
GCS 3 (intubated)

A massive transfusion is commenced. Shortly afterwards a ROTEM sample is run to assess the patient’s coagulation. A normal ROTEM sample is given for comparison, and both are shown on pages 6 and 7 of the supplementary examination booklet.

i. (5 marks)
Describe the main ROTEM findings and which blood product they indicate.

Must include:

Low EXTEM
Low INTEM
Low FIBTEM
Low APTEM

Which indicates administration of CRYOPRECIPITATE

1 mark for each statement

1 mark for product

Comment: this is a really nasty question. Sorry! It is unlikely that candidates will be asked a ROTEM question in the exam, but we wanted to make sure you had at least seen it, just in case. A good explanation of ROTEM can be found at https://derangedphysiology.com/main/required-reading/haematology-and-oncology/Chapter%201.2.0.1/intepretation-abnormal-rotem-data.

ii. (5 marks)

After the initial resuscitation of the patient, the ROTEM sample is repeated and the results are shown of page 8 of the supplementary examination book. Describe the findings and their implications.

Collapse of EXTEM, INTEM and FIBTEM after initial clot formation.
Maintenance of APTEM

Indicates fibrinolysis and administration of tranexamic acid.

1 mark for each statement

1 mark for product

Comment: same comment as above. Sorry!

iii. (4 marks)

The patient is taken emergently to the CT scanner. The patient’s CT scan of the brain is shown on page 9 of the supplementary examination booklet. Give the main findings.

Multiple fractures of the nasal bones
Multiple bilateral fractures of the maxillary sinuses
Bilateral fluid levels in maxillary sinuses
Fracture through L base of skull

1 mark for each statement.

QUESTION 6. (Continued from q5).

The patient from question 5 has an associated extradural haematoma. Urgent theatre is planned, and the neurosurgical registrar asks you to arrange a consent with the next of kin.

i. (2 marks)
Outline your response to this.

Consent must be carried out by the surgeon performing the procedure, and therefore ED will not undertake this.

1 mark each:
consent is a surgical issue
ED will not undertake it

Comment: this is a consultant level test of understanding where appropriate professional boundaries lie.

ii. (5 marks)
Give the components of informed consent.

Must include:

Patient must have capacity
Consent must be free and voluntary
Disclosure of risks/benefits of procedure
Patient must understand this
Must be within the boundaries of law (ie lawful)

1 mark for each point

Comment: this is one of the few true tests of straight knowledge in the admin area. This is a list that candidates just need to know.

iii. (4 marks)
The Neurosurgical registrar cannot reach any of the patient’s next of kin, nor can she contact her consultant for advice. She asks you under what grounds she should proceed. Outline the rationale for your response, and any actions you will take.

Themes to include

There is a common law duty of care to carry out emergency life/limb preserving procedures
In the absence of a surrogate decision maker, this patient has a life threatening injury and consent may be assumed.
In practice this will mean contacting the medical superintendent on call to confirm this independently
Clear documentation of this should be established.

1 mark for each theme

Comment: This is a high level discriminator, designed to test consultant level understanding of complex issues.

QUESTION 7.

A 2 year old girl presents as a resus call with the ambulance. She has had 45 minutes of seizures at home and is still seizing. She has a temperature of 39.6 degrees. The ambulance have given 2mg of IM midazolam, and have been unable to establish IV access.

i. (5 marks)

Outline your procedure for establishing emergent vascular access in this child.

Should include: immediate intraosseous access

1. IO drill or gun
2. Swabbed skin
3. 1-2cm below and medial to tibial tuberosity
4. Advanced until loss of resistance and marrow aspirated

1 mark for intraosseous route

1 mark for each item

Comment: the invitation in this question is to show consultant perspective on immediate access in a critically ill paediatric patient.

ii. (8marks)

Outline your immediate management of the patient post insertion of vascular access.

Must include appropriate doses of the below, for a calculated weight of 12kg:

midazolam 1.8mg IO repeated at 5 minutes if seizing
15mg/kg phenytoin or dose of levetiracetam IV
check BSL and correct if low (critical response)
treatment for CNS infection:
- 100mg/kg IO ceftriaxone
- acyclovir
- 0.15mg/kg dexamethasone
- notification to paediatrics/PICU of case

1 mark for calculated weight and 7 other interventions.

iii. (3 marks)
The child is transferred to PICU. On review of the record you note that she was discharged as a viral infection from ED 2 days prior. Outline your actions in response to this.

Review chart and interview doctors
Summarise findings and present them to the ED Director, along with any recommendations for change

1 mark for each element

Comment: this is quite a nasty question sorry! Again, it's included as content you might not have looked at.

iv. (5 marks)

You are asked to meet with the parents and explain events. List the elements of open disclosure.

Open and timely communication
Acknowledgement
Apology or expression of regret
Supporting and meeting the needs/expectations of the patient
Systems improvement based on this

1 mark per element

Comment - this is another short admin list that candidates just need to know.

QUESTION 8.

A 42 male presents to resus with severe vomiting. He has no medical history of note. He is transferred from the ambulance to the resus room with the following vital signs:

HR 135 /min
BP 85/42 mmHg
T 39.6 oC
RR 16 /min
GCS 15

i. (3 marks)

Your registrar presents you with a point of care venous blood gas. She notes that due to the patient’s degree of haemodynamic compromise she found IV access very difficult. The blood gas is shown on page 10 of the supplementary examination booklet. List the major acid base abnormalities.

1. Primary metabolic akalosis
2. Appropriate respiratory compensation
3. A raised anion gap acidosis

1 mark for each of these.

Comment: This is an old exam trick – specifically hiding a raised anion gap in an alkalotic ABG. If you trawl through past exams, you’ll see this arise occasionally. The examiners love it. If you look above, you’ll be able to calculate an Anion Gap of 30. Again, there’s not many ways to disturb an anion gap without creating an acidosis.

ii. (5 marks)
An ECG is immediately taken from the patient, and is shown on page 11 of the supplementary examination booklet. Describe and interpret the ECG.

1. Rate 84/min
2. Normal axis
3. Normal PR/QRS intervals
4. No conduction defect

This is a NORMAL ECG

1 mark for each and 1 mark for understanding this ECG is normal.

Comment:

Every word in the stem/information you are given counts. Get used to reading and thinking about what you are told.
Be prepared for the exam to occasionally test perspective. The issue in this question is not the medical management of hyperkalaemia, but rather the ability to recognise a false positive result.

iii. (6 marks)
Outline your next management steps.

Must include:

1. Recheck Potassium: the VBG and ECG results are discrepant, and one must be incorrect

2. Telemetry while this is established

3. IV fluid rehydration given underlying metabolic acodosis and vomiting illness.

Note - 2 marks for each element.

Comment: This entire question is a high level discriminator, aimed to test consultant level perspective.

QUEstion 9.

A 23 year old woman presents to your department with headache. She describes a migratory, generalised headache that has gradually developed and has been largely persistent for 2 weeks. She describes varying and transient neurologic symptoms including blurred vision, dizziness and difficulty concentrating. The headache severity varies irregularly. Her only medication is the oestrogen only contraceptive pill

Her vital signs are:

HR 90 /min
RR 16 /min
O2 sats 99% on RA
BP 131/71 mmHg
GCS 15

i. (6 marks)

List 6 differential diagnoses for this presentation.

MUST INCLUDE:
Brain tumour
Dural venous sinus thrombosis
Encephalitis

And any from:

Meningitis
Migraine
Sub arachnoid haemorrhage
Tension headache
Cluster headache
Conversion disorder
Mental illness
Gateway presentation
Or other reasonable cause of headache

1 mark for each of these two diagnoses. NOTE, these are critical omissions if not stated, and will reduce mark to 1.

1 mark to a maximum of three for further diagnoses.

Comment: as always, the most likely and important diagnoses should be listed first.

ii. (4 marks)

A contrast CT scan of the patient’s brain is performed, and an image is shown on page 12 of the supplementary information booklet. Give 2 major abnormalities and the diagnosis

Filling defect in R transverse sinus
Loss of cerebral architecture

Diagnosis: transverse dural venous sinus thrombosis.

1 mark for each reasonable item

2 marks for diagnosis.

Comment: again, the clinical information provided needs to incorporated into the candidate's thinking so as to provide an answer with perspective.

iii. (2 marks)

Outline 2 management steps you will now institute.

1. Anticoagulation - either heparin infusion or 1-1.5mg/kg enoxaparin
2. Referral to neurology.

1 Mark each

Comment: make sure disposition is always considered as part of management.

question 10.

A 5 year old girl is brought in by her parents. They are concerned that she may have ingested her grandmother’s iron tablets, thinking they were chocolate lollies. The ingestion occurred 45 minutes ago. The child is well. No other medications were involved.

i. (4 marks)

Outline your investigation strategy for this child.

Must include:

Perform an abdominal xray
if no tablets visualised no further Ix needed.
If tablets seen then check serial serum iron level

1 mark
1 mark
2 marks

Comment: This is a simple test of basic - but must know - toxicology knowledge

ii. (4 marks)

The patient’s abdominal xray is shown on page 13 of the supplementary information book. Describe the major findings and the implications.

Large number of radio-opaque tablet shaped objects in stomach.
Likely iron ingestion
Therefore serial serum iron levels are indicated.

1 mark

1 mark
2 marks: must mention serial exams are needed.

iii. (5 marks)

Blood tests are taken from the child approximately 1 hour after the ingestion, and the results are shown on page 14 of the supplementary information booklet. Describe your actions and further investigation strategy.

Must include:
Non toxic serum iron level
But 1 hour post ingestion.
Needs to be repeated at 4-6 hours.
If iron levels <90 micromol/mg then repeat again at 4 hours
If falling then no further treatment necessary.

1 mark for each

iv. (2 marks)

The child’s repeat blood tests at 6 hours are shown on page 14 of the supplementary information booklet. Outline your next actions.

Start desferrioxamine 15mg/kg.hr
Admit under paediatrics/PICU or toxicology

1 mark each.

Comment - this question is a simple run through iron toxicity, an important toxicologic subject for candidates to know.