Defibrillation & Cardiac Pacing & Peri Arrest Arrhythmias Flashcards
What are the shock energies for defibrillation in ALS?
120-360J
Start 120 - 150 - 200J
Fixed or escalating strategy
Steps to reduce risk if ICD in situ when defibrillation?
Defib electrodes >8cm away from electrodes
in AP, PL or bi-axillary positon
What does ring magnet do on ICD?
Disable defibrillation function
Does not impact ability of device to pace
Methods of pacing - non invasive and invasive?
Non Invasive
- Percussion pacing
- Transcutaneous Pacing
Invasive
- Temporary Transvenous Pacing
- Permanent Pacing
What is percussion pacing? And how it is performed?
Bradycardia so profound, fist pacing can be used to produce adequate cardiac output
Ventricular standstill is a good example
- Closed fist side, firm thumps just lateral to lower left sternal edge
- Monitor ECG for QRS complexes each thump
- If not then move fist or hit harder
- If no QRS then start CPR immediately
What is transcutaneous pacing? And how to perform?
Skin dry, razor excess hair
Apply pads in usual positions
Rate 60-90bpm
Gradually increase amplitude until pacing spike at each QRS (50-100mA)
If not and on highest amplitude - change positions or could indicate severe hyperkalaemia or non viable myocardium
How can transvenous temporary pacing fail?
High Threshold (rises in time, ensure all captured)
Connection failure
Lead displacement
Initial assessment of adult tachycardia - Step 1?
O2 if hypoxic
IV Access
ECG, BP, SpO2, 12 Lead ECG
Identify and treat any reversible causes (electrolytes, hypvolaemia)
What are life threatening features in tachycardias - Step 2?
Shock (systolic BP <90, impaired consciousness, pallor)
Syncope
Myocardial Ischaemia
Severe Heart Failure
Management if life threatening features in tachycardias - Step 3?
Synchronised DC Shock (120-150J)
Up to 3 attempts
If unsuccessful - Amiodarone IV 300mg over 10-20 minutes (followed by 900mg 24hr infusion)
Then repeat synchronised DC shock
Management of non life threatening tachycardias - Narrow Complex - Regular and Irregular?
Regular (SVT)
1. Vagal Manoeuvres (carotid sinus massage or valsalva)
2. Adenosine 6mg IV, then 12mg IV, then 18mg
3. IV Verapamil or Beta-Blocker
4. Synchronised DC Cardioversion up to 3 shocks
Irregular (AF)
1. Beta blocker
2. Consider digoxin or amiodarone (if HF)
3. Anticoagulate if >48 hours
Management of non life threatening tachycardias - broad complex tachycardia - regular and irregular?
Irregular
1. AF with BBB - treat as irregular narrow complex
2. Polymorphic VT - give 2g IV MgSO4 over 10 minutes
Regular (VT)
1. Amiodarone 300mg IV over 10-60 minutes
2. If previously known SVT with adherent conduction then treat as regular narrow complex tachycardia
3. If unsuccessful then Synchronised DC cardioversion
Causes of regular broad complex tachycardia?
Ventricular Tachycardia
SVT with BBB
Safest to treat all as VT unless certain previous diagnosis
Causes of irregular broad complex tachycardia?
AF with BBB
AF with pre-excitation (WPW)
Polymorphic VT
Causes of regular narrow complex tachycardias?
Sinus tachycardia - treat underlying cause
SVT
Atrial Flutter with regular AV block
