inItiation roadblock answers.

The marking scheme we used for the initiation roadblock is reproduced below for anyone who wants to work on their answers.

Question 1.

i. (4 marks)
Give 4 signs on chest examination that may indicate the possibility of a pneumothorax. 
 
Must include (4 of):
-surgical emphysema/chest crepitus
-decreased air entry on affected side
-tracheal deviation away from the affected side
-penetration of the chest wall
-decreased expansion on the affected side
 

ii. (4 marks)
The patient’s chest xray is taken just after arrival and is shown below. Give 2 major abnormalities from the film and the diagnosis. 
 
Major abnormalities
-deep sulcus sign on the left
-fracture of the left 8th rib
 
therefore diagnose left sided (1 mark) pneumothorax (1 mark)
 
iii. (2 marks)
After the patient’s xray returns he suffers increasing respiratory distress, de-saturates and has a cardiac arrest. What two actions would you immediately undertake? 
 
Must include:
-cold intubation (the patient has arrested, and therefore does not need rapid sequence)
-immediately decompress left chest by finger thoracostomy (note significant fail rate of needle decompression means it is less likely to be useful here, and tube thoracostomy takes too long)
 
iv. (1 mark)
After your actions above the patient regains immediate output but remains hypotensive with a systolic BP of 78mmHg. What volume resuscitation will you administer to this patient?
 
-immediate administration of packed red cells 2U O-ve (no marks for crystalloid)
 
 
v. (5 marks)
Give 5 endpoints you would use to judge the efficacy of your volume resuscitation.
 
Must include 5 of:
 
1.Normalization of haemodynamics (SBP >90, HR 100)
2.Capillary refill time approaching 2 seconds
3.Urine output >0.5ml/kg.hr
4.Lactate clearance of 50%/resolution of metabolic acidosis
5.Maintenance of normal haemostatics (INR as close to 1 as possible, normal TEG profile if available)
6.A normal clinical state, particularly normal mentation.

Question 2.

i. Which induction agent will you use to intubate this patient? Justify your choice. (2 marks)

Must include (must give drug doses to score any marks, plus a further mark for each reasonable justification):
- ketamine 1-1.5mg/kg: more likely to support blood pressure in head injury
- midazolam .1mg/kg & fentanyl 200mcg: cardiovascularly stable
- etomidate (for NZ ACEM trainees!)

ii. Using the table below, give 2 paralytic agents you would consider using, the dose of each agent, and two advantages and disadvantages of each. (12 marks)

Suxamethonium 

​1-1.5mg/kg

1.  short acting
2. rapid onset
 or others from:
Literature suggests gives optimal intubating conditions
Commonly used

1. multiple side effects:
- risk of malignant hyperthermia
- raises ICP, IOP etc
- raises K+
 
2. no reversal agent
​

Rocuronium

>1.2mg/kg

1. Rapid onset if high dose given
2. reversible (sugammadex)
No adverse affects on pressure
Less risk malignant hyperthermia


1. long acting
 
 


2. not suitable for RSI if under dosed

Question 3.

i. (5 marks)
Using the table below list five anatomic structures which may be injured, and a clinical complication for each. 

STRUCTURE

carotid artery

jugular vein

trachea

lung

thyroid gland

ansa cervicalis

CLINICAL FEATURE

anterior/middle circulation CVA

major haemorrhage

airway compromise/air bubbling in wound

Pneumothorax/respiratory distress

major haemorrhage

horner’s syndrome

ii. (3 marks)
Is imaging appropriate in THIS patient and why?
 
Must include (1 mark for each theme):
-the patient is relatively stable/ if there is no clinical contraindication (airway compromise, exsanguination etc) imaging can be conducted
-possibility of vascular injury and foreign body must be considered
-in stable zone 2 injuries imaging may reduce the rate of negative exploration
-and is likely to be valuable in planning operative intervention
 
-therefore if there is no clinical contraindication (airway compromise, exsanguination etc) imaging is appropriate
 
iii. (4 marks)
List 2 important imaging studies that you could perform and the indication for each.
 
-the patient should have:
-a CXR (Ptx)
-CT angiogram of the neck- dissection, blush indicating arterial bleed

question 4.

i. (3 marks)
A venous blood gas is taken by the resident, and results are shown below.
What are the major acid-base disturbances present? 

Must include:
Raised anion gap metabolic acidosis
Compensatory respiratory alkalosis
Intercurrent metabolic alkalosis

ii. (2 marks)
Provide 2 derived values to support your answer. 
 
Must include:
-Anion Gap = 24
-Delta ratio = 2.0

iii. (4 marks)
List 4 differentials for this patient’s presentation. 
 
Must include: (1 mark each)
-diverticulitis
-perforation post colonoscopy
 
plus 2 other reasonable differentials (for 1 marks each)
-UTI
-ischaemic mesentery
-etc

iv. (3 marks) 
A CT scan of the patient’s abdomen is shown below. What is the major abnormality and what diagnosis does it imply?

Must include:
-abnormality: extraluminal air seen lateral to descending colon
-suggests a contained perforation of the descending colon

Question 5.

i. (4 marks)
List 3 abnormalities on the ECG and give your diagnosis.

1. More p’s than QR’s
2. P-p interval constant
3. PR interval increasingly prolonged
4. PR interval shortest following missed QRS

Wenckebach block
 
ii. (6 marks)
List 3 potential causes of these changes and give an example of each.

1. Drugs- beta or calcium channel blockers, dig, amio
2. MI(inferior)
3. Inflammatory conditions: myocarditis, endocarditis
4. Others:
   1. infiltrative conditions-amyloid, sarcoidosis, malignancy
   2. electrolyte abnormalities: hyperkalaemia

 
iii. (3 marks)
Give 3 pharmacologic therapies you could institute if this patient became bradycardic and hypotensive.
Atropine 400mcg – 600mcg bolus
Isoprenaline 5mcg/min titrated BP 90
Adrenaline 10-20mcg bolus or 5mcg minute titrated BP 90
 
iv. (5 marks)
​In the event of non responsiveness to drugs, describe your procedure for transthoracic pacing.
 
Must include:

• light sedation/analgesia (midazolam 2.5mg aliquots or ketamine 20-50mg aliquots)
• monitor through leads, pads on also
• pace through pads placed AP or AL
• titration of current to electrical and mechanical capture (threshold)
• set rate 80-100 for BP >90 systolic

Question 6.

i. (3 marks)
What are the major abnormalities, and what do they suggest? 
 
Must include:
-disproportionate rise in GGT/ALP over transaminases
-hyperbilirubinaema
 
suggests biliary tree obstruction.
 
ii. (2 marks)
Your registrar has ordered a chest xray and the film is reproduced below. What is the major abnormality and what is the likely diagnosis in view of the information you have so far gathered? 

Must include:
-free air under right hemidiaphragm
-in view of history and LFTs suggests gallbladder perforation due to necrosis/infection
 
iii. (5 marks)
List 4 important management interventions you will institute
Must include:
-IV analgesia 0.1mg/kg morphine or similar titrated to pain (1 mark)
-IV antibiotics: (2 marks if appropriate regime and doses are specified)
-ampicillin 1g, metronidazole 500mg and gentamicin 5-7mg/kg
-ceftriaxone 1g IV and gentamicin as above
-urgent surgical referral (1 mark)
 
plus any other reasonable management step for 1 mark.
-IV fluid
-NBM
-Etc

question 7.

i. (6 marks).
The patient’s venous gas is reproduced on page 9 of the supplementary information booklet. 
Describe and interpret the major abnormalities. Provide calculations where relevant to support your answers.

given low HCO3-:      Metabolic acidosis
Expected CO2  :        (1.5 x 15) + 8 = 29  It is 22.
.: diagnose concurrent respiratory alkalosis
 
Anion Gap 137 - (100+15) = 22 = raised anion gap.
Delta ratio = (22-12)/(24-15) = 10/9 = 1.1. .: diagnose isolated RAGMA
 
K+ is low –expected for pH (3x0.5) + 5 = 6.5
 
This is most likely a salicylate overdose.
 
ii. (3 marks)
What active treatment apart from haemodialysis, would you commence on this patient? 
Charcoal 50g – repeat dose if salicylate rising.
Urine alkalinization – Aim pH 7.5: give Na H2O at 1 mmol/kg then infusion
Maintain urine output 1-2ml/kg/hr with IV crystalloid
 
iii. (4 marks)
Give 4 indications for haemodialysis in this patient
 
Metabolic  acidosis not responding to urinate alkalinisation
Serum salicylate concentration – 6mmol/l
Renal Failure, fluid overload.
End organ failure- cerebral oedema, seizure.
 
iv. (4 marks)
Outline your criteria for medically clearing this patient for discharge.
 
​If asymptomatic with normal VBG and falling salicylate levels in therapeutic zone (1.1 -2.2mmol/L )
all other patients must be observed for a minimum of 12 hours due to erratic peak levels.

Question 8.

ii. (2 marks)
Describe this burn?

• Burn over left shoulder of variable thickness
• Some vesicles
• Sloughing of skin
• Also erythema and blistering to the face.

 
Therefore a mix of superficial and moderate partial thickness burns <10% BSA (2 marks)
 
iii. (6 marks)
Give 6 steps in your initial management of this patient.

• Cool the burn with running water
• Clean and cover the area plus de-roof blisters(/or not- controversial!)
• Analgesia: intranasal fentanyl 1.5mcg/kg or parenteral opiods
• Silver impregnated dressing: acticoat, mepilex Ag or flamazine with occlusive dressing
• Check and update tetanus status
• Contact child’s guardian/social work/some other “fluffy bunny” statement

 
iii. (5 marks)
List 5 characteristics of burns that mandate transport to a burns centre.

• Partial/full thickness burns in children >5%
• (In adults partial thickness >10%/full thickness>5%)
• Burns to face, hands, feet, genitalia, perineum and major joints
• Chemical burns
• Electrical burns including lightning
• Circumferential burns, limbs,chest
• Burns with trauma

question 9.

i. (5 marks)
List 5 features you would seek in history or examination to evaluate the severity of potential oesophageal burns.

• Quantity taken     
• Vomiting
• Drooling
• Oesophageal pain
• Abdominal pain
• Stridor
• Burns in the oropharynx

ii. (6 marks)
List 6 investigations would you order in this patient and why.

• Bedside:
  • ECG – coingestant with toxicologic features
  • BSL – screen hypoglycaemia
• Labs:
  • paracetamol levels – co ingestant
  • FBC – bleeding
  • VBG: check pH and acid base balance
  • UEC – check renal function and HCO3-
• RADIOL: CXR –Upright ?mediastinal free air
• Consider CT with PO Contrast following discussion with GIT

iii. (7 marks) 
Comment on the role and use of the following in this patient .

• Mouth rinse + drink 250 ml of water / milk

Controversial for dilution but may have no role

• Activated charcoal- No role
• Aspiration of stomach contents- no role
• Neutralising stomach contents- no role
• Intubation – if stridor airway compromise , hypoxia
• Broad spectrum antibiotics- no role early only in proven perforation.
• Corticosteroids- Controversial- usually given post scope

In severe injury may increase risk of perforation.

iv. (2 marks)
Briefly outline your discharge criteria for any patient presenting to the ED following corrosive ingestion. 
​
Asymptomatic patients
Especially if small ingestions of weak compounds
Advise to return if become symptomatic- abdo pain- swallowing differently.

question 10.

A decision is made to perform a rapid sequence intubation. Following induction and paralysis, the patient’s airway obstructs and she becomes unable to be bagged. A view of the cords is unobtainable on laryngoscopy due to upper airway haematoma obstructing the view.

The patient has desaturated to 82% and you are not able to ventilate.
 
iv. (8 marks)
List 4 approaches you might take to secure the airway with either an advantage or disadvantage for each.
 
Blind intubation- dislodge clot
Surgical airway- cut into haematoma, committed as cant ventilate
Video laryngoscopy- may be able to see a way around
Fibreoptic- may dislodge clot with scope
Retrograde- cut into clot
Laryngeal mask- may ventilate and then can delay until rigid scope is available.
 
ii. (3 marks)
A CT scan of the patient’s c-spine is taken and an image is shown below. What are the major abnormalities?
​
Must include:
-comminuted fracture of the dens (1 marks)
-anterior displacement of body of C2 on C2 (1 marks)
-significant changes of osteoarthritis (1 mark)
 
iii. (3 marks)
List 3 clinically important complications of this injury. 
 
Complications:
-respiratory failure
-quadriplegia
-spinal shock
 
The patient’s CT scans (pelvis, abdomen, chest & head) show no other injuries. There are no long bone fractures evident on secondary survey.
 
The patient’s vital signs are:
 
HR                  41       /min
BP                  72/42 mmHg
RR                  16       /min (ventilated)
O2 sats         100% FiO2 tube 40%
 
iv. (1 marks)
Name this type of shock.
 
Neurogenic
 
v. (2 marks)
Give 2 interventions you will apply to treat this issue.
 
Must include (1 marks each):
-administration of fluid bolus 20-40ml/kg
-in the event of ongoing hypotension use of inotropes (adrenaline or noradrenaline titrated) to maintain HR and vasomotor tone.