Various

Question 1

Hypercarbia in COPD Mechanism (5 points)

Answer 1

• Reversal of hypoxic pulmonary vasoconstriction, causing high levels of CO₂
  in poorly ventilated alveoli to diffuse back into the circulation.
• Decreased ventilatory drive.
• Decreased CO₂ buffering capacity of haemoglobin.
• Absorption of CO₂ from alveoli beyond obstructed airways.
• The higher density of oxygen compared with air causing increased work of
  breathing.

Question 2

Signs of hypercarbia in a CO2 retaining patient

Answer 2

The signs of a rising carbon dioxide level are usually confusion, drowsiness, agitation and a falling level of consciousness.

Question 3

Consider IPPV +/- PEEP in these settings

Answer 3

• SpO₂ continues to fall below 80% despite treatments, or
• The patient is becoming exhausted, or
• The patient is suspected of developing hypercarbic respiratory failure
  despite lowering the oxygen flow.

Question 4

CPAP and PEEP Cautions

Answer 4

Altered level of consciousness
Vomiting
Signs of shock

Question 5

Pysiological effects of CPAP and PEEP

Answer 5

• Reduce shunting (fluid filled airways collapse), improves recruitment.
• Wet lungs are stiff and hard to expand, increased inspiratory pressure assists these in expanding.
• End expiratory pressure splints open small and medium airways, prevents collapse
• Positive pressure in thoracic cavity reduces preload of RV
• Positive pressure in thoracic cavity increases the afterload of the right ventricle and reduces venous return to the heart. This reduces blood flow through lung vessels, reducing the amount of fluid entering the lungs.
• Expiratory pressures increase FRC - more of the lung remains expanded, less work required to inflate

Question 6

Cardioversion Checklist

Answer 6

• Place pads in either the apex/sternum (recommended) or anterior/posterior
position, in addition to ECG electrodes.
• Ensure the defibrillator is in manual mode.
• Select a lead with a visible R wave and ensure that artefact is minimised.
• Select synchronised mode.
• Confirm there are detection symbols with most QRS complexes.
• Ensure the patient has received adequate sedation if indicated.
• Select maximum joules, charge the defibrillator and confirm everyone is clear.
• Press and hold the shock button until the shock is delivered.
• Determine the rhythm and reassess vital signs.
• If administering a second cardioversion, confirm the defibrillator is still in synchronised mode and the patient is adequately sedated.

Question 7

MCI - Patients considered almost certain to die

Answer 7

Respiratory Arrest
Severe Shock with falling HR
GCS 3, pupils fixed and dilated
** Decision should be made by very experienced clinical personnel .

Question 8

MCI - Primary Triage actions

Answer 8

METHANE sitrep asap
Open Airways
Compress life threatening external bleeding - utilise bystanders or other ES personnel
Move patients to Casualty clearing point

Question 9

MCI - Secondary triage actions

Answer 9

Primary and secondary surveys
Allocate each patient a number
Create central record - number, status, injury description, age, status
Treat as based on priority
Treat based on “greatest survivability with least required resources”