Interlude exam 1 answers

The exam answers for Interlude 1 are below, with a suggested marking schema to allow you to score yourself. The important things to remember are the lessons from the initiation roadblock - answer succinctly and scientifically. The value here is the invitation to you to critique your own paper, and gain both insight and reinforcement into how you are answering questions. Feel free to post any questions to the course facebook page.

QUESTION 1.

A 48 year old man presents to your department by ambulance a fire at a factory. He has sustained mid to deep thickness burns circumferentially over his right arm, his entire head, and his anterior torso and abdomen. You estimate his weight at 80kg.

His vital signs on arrival are:

HR                    119      /min
BP                    103/66mmHg
RR                    28        /min
O2 sats 95%     6L via mask
GCS                  15

i. (4 marks)

Calculate the percentage of body surface area involved in this man’s burn.

Percentage body surface area:

Entire right arm
Entire head
Anterior torso and abdomen

Total

9%
9%
18%

36%

I mark for each correct number.

ii. (7 marks)

Describe your fluid management strategy for this patient, including your underlying formula.

Parkland Formula: 4ml/kg x %BSA

4ml x 80kg x BSA
= 320ml x 36%
= 11.52L of Hartmann’s solution

Half in 1st 8 hours, remainder next 16hrs

Titrate to urine output 1ml/kg higher threshold than 0.5ml/kg.hr (as this is a burns patient)

Monitor K+/renal function

1 mark for formula

2 marks for the correct calculation

2 marks for this statement

2 marks for specification of endpoints

Comment - as this question asks for a description of strategy (read management) it is important candidates articulate both interventions, and the basis underlying them, and also endpoints.

iii. (4 marks)

You are concerned about the patient’s airway status. Besides the facial burns themselves, give 4 examination findings that would indicate an airway burn.

Any from:

Swollen/cracked/burnt lips or tongue
Intra-oral burns
Singed nasal hairs
Carbonaceous sputum
Hoarse voice
Stridor

1 mark per answer to a maximum of 4.

iv. (8 marks)

Based on your findings above you elect to intubate the patient in the resus room. Your fellow consultant asks you to prepare for a surgical airway. Describe the procedure you will use in the event of failed oral or nasal intubation.

1. Aseptic technique (if time)
2. Transverse scalpel division of skin over cricothyroid membrane
3. Puncture membrane
4. Insert finger or tracheostomy forceps
5. Place bougie into incision
6. Railroad size 6 ETT over bougie
7. Inflate tube cuff and test ventilate.
8. Mechanical tamponade/surgical control of any bleeding.

1 mark for each point or variation thereof.

Seldinger cricothyroidotomy is also acceptable.

Comment: this is a high mark management question. Observe the suggested answer above, and note that it is clear and stepwise in its detail, uses scientific language for precision, and does not use excess prepositions or adjectives.

When we tell you that management needs to be "instructions that the intern can follow" this is what we mean.

QUESTION 2.

A 60 year old man is brought by ambulance to your emergency department after a fire at a factory. He has no airway compromise or evidence of cutaneous burns, but he is GCS 12 and acutely confused.

An arterial blood gas is shown on page 2 of the supplementary information booklet.

The patient’s vital signs on arrival are:

HR                    105      /min
BP                    106/72mmHg
RR                    31        /min
O2 sats 100%   Room air
GCS                  12

i. (10 marks)

Describe and interpret the patient’s blood gas.

Must include:

Primary respiratory acidosis
Raised anion gap metabolic acidosis
Anion Gap 35 & Delta ratio 1.1

Significantly high carbon monoxide titre
Saturation gap between observations and ABG measurement plus critically raised lactate

Therefore diagnose:

Carbon monoxide toxicity
Cyanide toxicity

1 mark
1 mark
1 mark each

1 mark
1 mark
1 mark

2 marks
2 marks

Comment: the key here is to note two things:
1. This is a high mark question, and therefore a degree of exposition is required.
2. You are asked for an interpretation. A brief inspection of the follow on questions indicates that you are required to give specific management items. The clear implication that should be made is that this is a diagnostic ABG, and that therefore at least one diagnosis should be given.

As an additional aside, the mention of fire in a stem followed by an ABG should always prompt close scrutiny for both carbon monoxide and cyanide toxicity.

ii (6 marks)
Outline your specific management of this patient.

Must include the following elements…

Cyanide toxicity
1. Hydroxycobalamin 5g IV over 30 minutes (dilute 200ml 5% dextrose)
2. Sodium thiosulfate 12.5g over 10 minutes
3. Repeat if no resolution of acidosis, clinical state or lactate level after 15 minutes

Carbon Monoxide poisoning
1. High flow O2 15L via NRB
2. Referral to hyperbaric unit for consideration of hyperbaric O2

1 mark

1 mark
2 marks

1 mark
1 mark

Comment - this is a high level discriminator, that requires specific knowledge and the ability to make a diagnosis from an ABG. As a clue, hyperbaric oxygen should be included here based on Q3.

That said, if you can remember the ABG and the treatment above, you probably have just learnt the majority of what you need to know about both cyanide and carbon monoxide for the exam.

iii. (3 marks)

Give 3 indications to consider hyperbaric oxygen for this patient

Any from:

Altered mental state
Confusion
Metabolic acidosis
Age >55 years
Presence of cerebellar signs on exam
ECG changes

1 mark for any of this list

QUESTION 3.

You are asked to review your department’s radiology from the weekend. You find the xray of a 25 year old male who fell on his outstretched arm playing rugby league.

A clinical image of the patient’s xray is shown on page 3 of the supplementary information booklet.

The clinical notes record that the patient was diagnosed with a wrist sprain and discharged with a crepe bandage for GP follow up.

i. (3 marks)
Give two abnormalities present and a diagnosis.

Must include

Widened scapholunate space
Signet ring sign
Diagnosis: scapholunate dislocation.

1 mark for each point

ii. (3 marks)
Outline 3 actions you will now take.

Must include
1. Recall patient for cast and orthopaedic referral
2. Apology for mistake
3. Initiation of some sort of investigative process
any is acceptable (department, patient safety etc)

1 mark for each point

Comment: these questions can be difficult (we discuss this in the admin webinar). That said, this is really - as so much of admin is - about translating common sense into three points. A successful answer does not need to have these three specific points, but should incorporate the themes of contacting the patient to arrange follow up care, explaining or apologising, and reviewing the incident from a quality perspective.

iii. (5 marks)
The Emergency Director asks you to investigate the incident. Outline 5 steps you will take to do this.

1. Review of medical record
2. Interview staff members concerned
3. Formulation of a report including identification of factors
4. Circulation of the report to stakeholders (director, other staff specialists as appropriate)
5. Recommendations to prevent recurrence

1 mark for each theme

Comment - when we come to the admin webinar, you will see that this is effectively the application of a generic list to a specific problem. The themes involved in this answer can be used to answer many if not all complaint/critical incident type questions.

iv. (3 marks)
List 3 interventions that you can undertake to prevent a recurrence of a similar incident.

Themes from any of the following:

Education – M+M, xray review sessions for junior staff etc
Individual factors – identification on staff knowledge gap and management of same
Quality – improve xray reporting time, radiographer flag of abnormal results, phone through abnormal reports etc
Quality – senior review of all discharged patients, development of a specialist minoir injuries stream etc

1 mark for any answer based around the these themes.

Comment: we again cover off on this in the admin webinar. Unlike many medical questions, where a request for items (differential diagnoses, interventions etc) comes from a relatively small set of items, the possibilities here are myriad. This is a common source of anxiety for exam candidates, because the comfort of learning a list to regurguitate is not present. The key learning point here is that like so much of admin, answering is about translating experience and common sense. If candidates are able to think of initiatives around X-ray safety in their own departments and write them here, then they should be able to answer the question well.

QUESTION 4.

Question 4.

A 45 year old man presents having developed palpitations 4 hours previously. He is definite that this is the time of onset. He has no medical history of note.

His vital signs are:

HR        140                  /min
BP        120/80mmHg
RR        17                    /min
Sats      98%                 RA
T          37.1                 oC

i.(6 marks)
His presentation ECG is shown on page 4 of the supplementary clinical information booklet. Describe the ECG and give the diagnosis.

Rate: 132 and irregular
Axis: normal
No p waves
QRS: approx. 0.12s
Widespread t wave inversion

Diagnosis: AF

1 mark for each point.

ii. (9 marks)
Give 3 options for managing this rhythm and a pro and con of each.

OPTION

1. Conservative management
+/- MgSo4
+/- Metoprolol

2. Amiodarone infusion

3.Electrical cardioversion

PRO

Approx. 2/3 reversion at 24 hours
No need for sedation etc

Active treatment
May immediately cardiovert

Highest success rate

CON

May fail
Delayed outcome
Requires review in ED next day

Risk of drug toxicity
Significant failure rate

Requires sedation
Resource intensive

Marking:
1 mark for each option
1 mark each for a reasonable pro and con (as above) for each option.

Comment: This is to some degree a difficult question to ask but we have tried to do so to illustrate a key point. Pros and Cons type questions quite lend themselves to the exam format. A key learning point from this question is that when 'options' for management are considered, conservative management should usually be canvassed.

iii. (4 marks)
A decision is taken to electrically cardiovert the patient. Describe your procedure to achieve this.

1. Attach pads and leads
2. Energy selection 200J
3. Synchronise shock
4. Adjunct sedation eg ketamine 0.2-.5mg/kg by separate airway doctor

Comment: this 'describe a procedure' question is a bit harder, because it's only for four marks. This forces candidates to be succinct, while conveying all the critical steps.

QUESTION 5.

A 22 year old woman presents via ambulance to the ED with no prearrival phone call. She is G4P3 at 39+2 weeks and labouring. As she is wheeled into your resus room the vertex is on view.

The ambulance hands over that she has been labouring for 35 minutes, and has had appropriate antenatal care with no complications identified.

Her vital signs with the ambulance en route have been normal.

i. (8 marks)
Describe your process for the management of the second stage of labour

Reasonable process for delivery

Deliver head
Once head out, sweep neck to clear cord.
Await restitution and external rotation
Deliver anterior shoulder with gentle dorsal traction
Deliver posterior shoulder with gentle ventral traction
Deliver trunk and feet
At 60 seconds Cross clamp cord x 2 and cut
Assess child via APGAR and allow skin contact with mother

1 mark for each major theme.

Comment: this is a really nasty question. Sorry! That said, it's fair game. We have included it in this paper to make sure that candidates have taken the time to do a little revision on it.

ii. (7 marks)
The delivery of the child is uncomplicated. Describe your management of the third stage of labor.

Must include a reasonable method

Administer oxytocin 10IU IM
Assess uterine contraction
Perform uterine massage as needed
Await placental separation
Deliver placenta via controlled cord traction at 45 degrees
Check placenta is complete
Confirm fundal uterine contraction post delivery

1 mark for each theme

Comment: same comment as above. Sorry!

QUESTION 6.

A 78 year old woman presents to the after an unwitnessed collapse from standing height. Her medical history includes the atrial fibrillation, managed with metoprolol and warfarin. She has a headache.

Her vital signs are:

HR       95                    /min
BP        139/79            mmHg
RR        17                    /min
Sats      99%                 RA
T          36.6                 oC
GCS      15

i. (3 marks)
Give 4 clinical signs of skull fracture that you will assess as part of your examination of this patient.

Any reasonable answers, such as:

Soft boggy haematoma on palpation
Battle’s sign/bruising around eyes
Haemotympanum
CSF Rhinorrhoea

1 mark for each.

Comment: as always, it is important to make sure that clinical signs given as part of the answer are actually signs (things found on examination) that are specific to the condition specified (ie skull fracture). As an example "decreased GCS" is not a sign specific for skull fracture, and likely will not score marks.

ii. (8 marks)
Give 4 investigations you will order in this patient and a rationale for each.

Investigation

1. CT brain

2. BSL

3. INR/Coag profile

and then any others reasonable, such as:

4. ECG

Rationale

1. Define pathology

2. Exclude as cause for ALOC

3. Define coagulopathy (warfarin) in head injury

4. Evaluate AF/arrythmia as cause for fall

Marks

1 mark/critical omission

1 mark/critical omission

1 mark/critical omission

1 mark for any final reasonable answer

Comment: although not medically challenging, this question challenges candidates to show perspective, and not miss obvious or important investigations. In the stem there are clear indications to perform a CT brain and coags, and BSL should never be missed in a patient with ALOC.

iii. (5 marks)
The patient’s CT brain scan is shown on page 5 of the supplementary information book. Describe and interpret the major abnormalities.

CT interpretation must include:

Pneumocranium on left
Subdural haematoma on left
Overlying subgaleal haematoma

Interpretation should include

Likely underlying skull fracture
No midline shift/signs raised ICP

1 mark for each

1 mark for each interpretation

Comment: again, it is important not to miss the invitation to 'interpret' the CT findings.

iv. (2 marks)
The patient’s INR comes back at 1.8. Outline your management of this result.

1. IV vitamin K 5-10mg IV
2. Prothrombin complex concentrate 50IU/kg or FFP 15ml/kg

1 mark for each.

Comment: the key here is recognising that although the INR is not terribly deranged, this patient has clinically significant bleeding and should be managed actively.

QUESTION 7.

A 67 year old man presents with sudden complete painless visual loss in his left eye. He has a history of diabetes.

i. (6 marks)
Give 3 features on history you will enquire about and the potential disease they indicate.

Curtain falling – retinal detachment
Cobwebs or similar – vitreous haemorrhage
Amarosis fugax – CRAO

2 marks for each combination

Comment: it is important that any symptoms relate to painless visual loss, as specified in the stem.

ii. (4 marks)
A photo of the patient’s fundus is shown. Describe the major findings and the likely diagnosis.

Findings:

Pale anaemic retina
Cherry red spot
Small/indistinct vascular beds

Therefore Diagnose likely CRAO

1 mark for each finding and the diagnosis.

iii. (9 marks)
There is no ophthalmology service at your hospital. Briefly outline 3 possible treatments that may benefit this patient, and a pro and con of each.

OPTION

Occular massage – 5-15 seconds direct pressure to eye.

Anterior Chamber Paracentesis – aim for 0.1-02ml reduction

Acetazolamide 500mg IV or PO to decrease IOP

Directed fibrinolysis +/- interventional radiology

Hyperbaric oxygen therapy to improve tissue oxygenation

PRO

Quick, can be done at bedside

Can be done at bedside

Non invasive, bedside

Specific, may improve outcome in some cases

Non invasive, weak evidence to support outcomes

CON

Debatable evidence

No evidence that improves outcomes

No evidence to improve outcome

Weak/conflicting evidence, risk of bleeding, time critical

Requires specialist therapy

Marking: 1 mark for any three reasonable options and a pro and con for each.

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

QUESTION 8.

A 65 year old man presents with right sided rhythmic loin pain. He has a prior history of presenting to the ED 6 months prior with a right sided renal stone of 3mm, diagnosed on CT KUB. His vital signs are:

HR       85                    /min
BP        149/85            mmHg
RR        17                    /min
Sats      99%                 RA
T          37.1                 oC
GCS      15

i. (3 marks)
List three differential diagnoses.

Differentials must include:

Renal colic
AAA

Plus any other reasonable intra-abdominal Dx – gallstones, diverticulitis, appendicitis, UTI etc.

1 mark for each of these. Either being not articulated is a critical omission.

1 mark for a third reasonable diagnosis.

Comment: again, not a hard question, but an invitation to show consultant level perspective and include what is likely (renal colic) and what is serious and can't be missed (an aneurysm).

ii. (10 marks)
Give 2 medications classes you could use for analgesia and 2 advantages and disadvantages of each.

MEDICATION CLASS

NSAID

OPIATES

PROS

1. equally effective as opiates in trials

2. PO/PR/IM/IV formulations available

1. rapid onset, especially if given IV

2. Titratable

3. Familiar to most ED doctors

4. IV or PO formulations available

CON

1. do not assist stone passage

2. Risk of drug interactions

3. Contraindicated in GI bleeding/significant side effect profile

1. Side effect profile – vomiting, ALOC, respiratory depression

2. Addictive

3. Tolerance if already used

Marking: 1 mark for each class of drugs, and 1 mark for every reasonable pro and con.

Comment: this is included as another example of a pro/con question that candidates need to be able to answer.

iii.
(9 marks) Give three imaging options in this patient and an advantage and disadvantage of each.

IMAGING

None/conservative

CT KUB

USS KUB

ADVANTAGES

1. cheap/easy/no radiation

2. avoids transporting patient

1. gold standard, high Sn 97% & Sp 96%,

2. assess for stone, size and position;

3. also useful in exclusion of or confirmation of other causes

1. No radiation

2. Can be done at bedside

3. Repeatable/serial exams possible

4. If U/SS -ve for hydronephrosis, then no intervention necessary

DISADVANTAGES

1. non diagnostic

2. May miss other diagnoses

1. Involves ionizing radiation

2. Does not change management in a small stone

1. Only 60% sensitive for stones

2. Does not evaluate for other intra-abdominal diagnoses.

Marking: 1 mark for each imaging option, and 1 mark each for a reasonable pro and con for each option.

Comment: Again, it is important to include "not performing a scan" as an imaging option here.

QUEstion 9.

A 21 year old man presents to the ED with a severe left temporal headache of 24 hours duration. He describes 3 days of preceding left ear ache. He has no medical history of note. His vital signs are:

HR        105                  /min
BP        110/63            /min
RR        22                    /min
Sats      99%                  RA
T          38.6                 oC

i. (5 marks)
List 5 differential diagnoses for this presentation.

MUST INCLUDE:

Meningitis
Mastoiditis

Plus any of:

Encephalitis
Otitis media/externa
Sub arachnoid haemorrhage
Migraine
Or any other reasonable headache diagnosis.

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.

ii. (8 marks)
List 4 features you will seek on clinical examination, and the rationale for each.

Any from:

Otoscopy – examine ear drum for inflammation
Mastoid tenderness – mastoiditis
Kernig’s sign – meningitis
Neck stiffness – meningitis
Photophobia with ophthalmoscopy – meiningitis

1 mark for each reasonable examination performed and 1 mark for the rationale for each.

Given the history of ear infection, mastoid tenderness must be included, and represents a critical omission if left out.

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

iii. (4 marks)

The patient has a CT scan of the head performed. An image is shown on page 7 of the clinical information booklet. Describe the 2 major abnormalities and give a likely diagnosis.

CT findings

Fluid filled mastoid air cells
Erosion of petrous temporal bone on L
Diagnosis acute mastoiditis with likely CNS spread

1 mark for each finding
1 mark each for the diagnosis of mastoiditis and the mention of likely CNS spread.

Comment: again, candidates should show consultant perspective. It's important to indicate that the bony erosion likely indicates secondary CNS infection.

iv. (2 marks)

Briefly outline your 2 next major steps in management.

Treatment must include:

Administration of appropriate anitbiotics for CNS infection:
- Ceftriaxone 4g IV
- Cefotaxime 2g IV
Urgent referral to ENT and/or Neurosurgery

1 Mark each for the antibiotic and referral

question 10.

An 18 year old man presents after receiving an elbow to the face playing football.

He is given a triage category 4 and put in the waiting room.

i. (15 marks)
Fill in the table below for each category of the Australasian Triage Scale.

TRIAGE CATEGORY

1

2

3

4

5

REVIEW TIME

Immediate

10 minutes

30 minutes

1 hour

2 hours

COMPLIANCE RATE

100%

80%

75%

70%

70%

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

ii. (5 marks)

The patient has avulsed his right incisor and has the tooth with him in his hand. Describe your management.

Place tooth in storage medium, preferably milk
Irrigate socket with normal saline
Administer local anaesthesia to socket
Reimplant tooth and splint
Urgent dental referral/Maxillofacial referral.

1 mark for each correct element by theme