Chapter 9 Defibrillation Flashcards
Following cardiac arrest, how long till a patient suffers a hypoxic brain injury?
3 minutes
In the classic positioning of defibrillation pads (right chest below clavicle + left lower chest/axilla), how much current actually reached the heart?
As little as 4% (consider changing to AP position in refractory VT/VF)
The patient is very hairy and in VF and there are no clippers immediately available, what are your options?
1) Apply over hair and hope it works
2) Use a bi-axillary placement
Find clippers ASAP
Where do you place defibrillator pads for anteior-posterior placement?
Anterior over left precordium
Posterior just inferior to scapula
Preferred position for transcutaneous pacing
After termination of VF by defibrillation, how often does it return within a two minute period?
50%
Be ready
What can happy if you place a defibrillator pad over a pacemaker of ICD and deliver a shock?
You can damage the leads
Do not place pads over them and ideally should be 10cm away
What is the total time that should not be exceeded during a pause for defibrillation/rhythm check?
5 seconds
When you give 3 stacked shocks?
If 1st shock can be given within 20 seconds
Patient was monitored and pre-oxygened and well perfused beforehand
Rhythm is VT/VF
How do you give 3 stacked shocks?
Give 1st shock
Check rhythm and pulse or other signs of ROSC after shock
All 3 shocks count as 1st shock on algorithm
Does hold an infusion or the patient’s bed count as touching the patient during defibrillation?
yes
The patient is wet/very sweat and needs defibrillation, what should you do first?
Dry the patient. Shocking a wet patient is dangerous.
How far away should free flowing oxygen (mask, nasal prongs) be from the patient during defibrillation?
1 meter
A patient has an ETT/LMA connected to a bag-valve ventilator with 15L flowing. You need to defibrillate. Is this oxygen ok?
Yes.
Can leave bag attached with oxygen.
No oxygen will be in the zone of defibrillation.
Though if concerned about movement of the airway by unsupported bag-valve ventilator you can disconnect bag if you want.
A patient is on a ventilator already (ICU/surgical patient). Do you leave them on the ventilator or disconnect and use ventilation bag?
Ideally leave them on the ventilator (keeps their PEEP) but ensure they are still receiving adequate tidal volumes. If not, disconnect and use manual ventilation bag
The defibrillator is set to shock at 200J biphasic. How may joules can you go up to ?
360 J
What is the COACHED acronym stand for?
Compressions continue Oxygen away All others away Charge the defib Hands off Evaluate rhythm Defib or disarm
What phrase does the defibrillating person say to the person giving chest compressions if they are not sure if they are cleared of the patient before a shock is to be given?
“Are you safe?”
Do you ever feel for a pulse after defibrillation?
No (only if obvious signs of life)
Pause should be less than 5 seconds for defibrillation
It is the first rhythm check OR you have been on the shockable side of the algorithm and you see organised electrical activity during a rhythm. What do you do?
Look for signs of ROSC:
Central pulse
Rise end tidal CO2
If no signs of life, switch to non-shockable side of algorithm. Do not keep checking pulse during rhythm checks, once is enough.
When do you give amiodarone and how much?
300mg
After 3 shocks (any three, do not need to be sequetial)
When do you give adrenaline and how much ?
1mg immediately if non-shockable rhythm
After 2nd shock if shockable rhythm
Then every alternate loop
When do you use a paediatric defibrillator?
Age 1 - 8
What do you do if there is no paediatric defibrillator present for your paediatric patient and all you have in an AED set to 200J?
Use adult one but ensure pads are not overlapping. May need to use anterior-posterior in infants/very small children
During a sychronised shock for an atrial or ventricular tacharrythmia, where do you want the shock to land on the QRS complex?
R wave. On the R wave.
Do you use a synchronised shock for VT?
Only if they have a pulse.
If pulseless VT, non-synchronised
You want to do synchronised cardioversion. You have defibrillation pads on. What else can you apply to ensure a good cardiac tract is acheived?
ECG monitoring.
White = RIGHT (beneight right clavicle)
Smoke (black under left clavicle) over fire (red lead over left lower chest/abdomen)
The patient has an ICD that is firing. How do you stop it?
Place a magnet over the ICD and secure it in place with a strong adhesive.
the ICD may beep or vibrate to confirm it is disabled its ICD component.
A magent will NOT disable any pacing abilties.
What happens when you place a magnet over a permanent pacemaker?
Resets most pacemakers to asynchronous pacing however depends on each pacemaker.
Some are programmed not to be disabled by a magnet.
How many joules are needed for internal defibrillation (thoracotomy/cardiac surgery patient)
10-20 J for biphasic
Do not exceed 50J
