Chapter 6: Advanced Life Support Algorithm Flashcards
What are the shockable rhythms?
- VF
- Pulseless VT
What are the non-shockable rhythms?
- Asystole
- PEA
What are the key basic interventions required in all ALS scenarios to improve survival?
- Continuous high quality chest compressions
- Early defibrillation
You notice a patient is unresponsive and not breathing. What are the initial steps in the ALS algorithm?
- Call the resus team
- CPR 30:2
- Attach defibrillator/cardiac monitor
- one below right clavicle, other in V6 position in MAL - Count assistant in to take over chest compressions
- Assess the rhythm
You see a shockable rhythm. What are the next stages of management?
Related to shock energy
- Perform 1 shock (safely) at >150J (typically 200J)
- Immediately resume CPR for a further 2 minutes minimising interruptions
You have shocked a patient once but after 2 minutes, the patient remains in VF. What do you do?
- Safely deliver second shock - typically 300J
- Immediately resume CPR for further 2 minutes
Following 2 shocks, the patient remains in VF. What should you do?
- Shock again at 360J
- Give 1mg IV adrenaline (1:10 000)
- Give 300mg IV amiodarone
- While performing further 2 minutes CPR
How frequently is adrenaline given once it has been started?
- Every 3-5minutes (every alternate cycle)
- Continue for as long as cardiac arrest persist
If organised electrical activity is seen compatible with cardiac output following a shock, what should be done immediately?
3 things to check
Assess for ROSC:
- Check for signs of life
- Check for central pulse
- Assess end-tidal CO2
If there is organised electrical activity but no return of spontaneous circulation, what should be done?
- Continue CPR
- Switch to the non-shockable algorithm
Patient is in PEA
If there is return of spontaneous circulation and electrical activity following treatment for VF, what should be done?
Start post-resus care:
- Use ABCDE approach
- Aim for SpO2 of 94-98%
- Aim for normal pCO2
- 12 lead ECG
- Rx precipitating cause
- Targeted temp Mx
How frequently can amiodarone be given following VF/pVT?
With dosage
- 300mg after 3rd shock
- Further 150mg after 5 shocks
Lidocaine 1mg/kg can be given if no amiodarone available but don’t mix
When should precordial thumps be considered?
- Not recommended routinely
- Use when awaiting arrival of defibrillator
- Very low success rate for cardio version of shockable rhythm
How is a precordial thump given?
- Use ulnar edge of fist
- Strike sternum from height of 20cm
- Immediately retract fist
If a patient has a witnessed and monitored cardiac arrest with VF/pVT, what should be done?
- Give 3 quick successive shocks
- Rapidly check - rhythm change, pulse & signs of life
- If 3rd shock unsuccessful - Start compressions and continue CPR for 2 mins
- Continue normal ALS algorithm as if 1 shock has been given
When is adrenaline and amiodarone given if a patient has stacked shocks due to witnessed VF/pVT?
Adrenaline - assume as if stacked shocks are 1st shock - so after 2 further shocks
Amiodarone - give immediately (during CPR) as it should be given regardless after 3 shocks.
How are non-shockable rhythms managed according to the ALS algorithm?
- CPR 30:2
- Give adrenaline 1mg IV/IO
- Must be continued every 2 cycles regardless of whether it changes to a shockable rhythm
- Check rhythm at 2 minutes and respond as according to this
What classifies as a high quality chest compression?
- Adequate depth - 5/6cm
- Adequate rate - 100-120 bpm
- Ensure full recoil of chest after each compression
- Equal time compression & recoil
- Minimal interruption
- Aim to change individual doing compression every 2 minutes to avoid fatigue
What should be used to ventilate the patient if tracheal intubation is not possible?
Laryngeal mask airway
Supraglottic airway
What rate should the lungs be ventilated at?
If airway secured
10 breaths per min
Ventilate every 6 sec
What does the evidence suggest regarding intubation and survival?
No studies have shown tracheal intubation increases survival
What takes priority, tracheal intubation or continuing chest compressions?
- Tracheal intubation should only be attempted by trained providers
- Avoid stopping chest compressions
- Pause for up to 5s when passing through vocal cords
- Can defer intubation until after ROSC
How would you confirm that a patient has been intubated successfully?
Waveform capnography
What do you monitor during CPR?
- Clinical signs of life - breathing effort, movement, eye opening
- Pulse checks
- Monitor heart rhythm
- End tidal CO2 on waveform capnography
- Feedback or prompt devices
- Blood samples and analysis
- Invasive cardiovascular monitoring - e.g. cont. BP
- Focused echo/ultrasound can be used
What does the end tidal CO2 give a reflection of?
- Cardiac output
- Pulmonary blood flow
- Ventilation minute volume
Usually low during CPR - reflect low cardiac output.
If it normalises, indicate patient may be making resp. effort of own
What is the role of waveform capnography in CPR?
- Confirm tracheal tube placement
- Monitor ventilation rate - avoid hyperventilation
- Monitor quality of chest compressions - increase depth of compression, higher CO2
- Identify ROSC during CPR - Rise in end tidal CO2 may indicate ROSC
- Prognostication during CPR
What equipment may be needed for waveform capnography?
- Portable monitors that measure end-tidal CO2
- Side-stream sampling - connector req. in breathing piece
- Mainstream sampling
What are the stages of a waveform capnograph?
A-B = baseline - end of inspiration (CO2 in air)
B-C = start of expiration (start with no CO2 as from anatomical deadspace then increase)
C-D = alveolar plateau
D - end-tidal CO2 = maximal CO2 (normally 4.3-5.5)
D-E = inspiration begin
What should be done if there is a rise in end-tidal CO2 during a CPR cycle?
- Withhold adrenaline until the next rhythm check
- If cardiac arrest is confirmed - give adrenaline
Can end tidal CO2 be used to terminate CPR?
- While failure to achieve end tidal CO2 >1.33 in 20 mins = poor outcome
- It should not be used alone to terminate CPR efforts
What is important to know about giving drugs during CPR?
- Best to use peripheral cannula as don’t need to stop CPR
- Flush drug with 20ml fluid
- Raise arm for 10-20 seconds
- Can consider IO if IV is difficult to obtain
What are the main sites recommended for IO access in adults?
- Proximal humerus
- Proximal tibia
- Distal tibia
What are the contraindications to IO access?
- Trauma
- Infection
- Prosthesis at target site
- Recent IO access attempt (<48hr) in same limb
- Failure to identify landmarks
How is positioning of an IO confirmed?
- Aspirate - should see blood
- Absence of aspirate doesn’t imply failed attempt
What are the main complications associated with IO access?
- Extravasation into soft tissues
- Compartment syndromedue to extravasation
- Dislodgement of needle
- Fracture or chipping of bone
- Pain related to infusion
- Fat emboli
- Infection/osteomyelitis
What are the 4H’s and 4T’s of cardiac arrest?
Reversible causes of cardiac arrest:
- Hypovolaemia
- Hypoxia
- Hypothermia
- Hyperkalaemia, hypokalaemia,
- Hypoglycaemia, hypocalcaemia, academia, other metabolic
- Thrombus - coronary & PE
- Tamponade
- Tension pneumo
- Toxin
Why is a tamponade difficult to diagnose as a cause for cardiac arrest and how is it diagnosed?
- Typical signs such as hypotension and distended neck veins can’t be assessed
- Focused cardiac ultrasound performed to diagnose pericardial effusion
What would raise suspicion of cardiac tamponade as a cause for cardiac arrest?
- Penetrating chest trauma
- Post cardiac surgery
May require resuscitative thoracotomy
What probe position is recommended for focused ultrasound in cardiac arrest?
- Sub-xiphoid
<10s pause in compressions
When may automated chest compression devices be useful?
- CPR in moving ambulance where safety is at risk
- Prolonged CPR
- CPR during certain procedures:
- Coronary angiography
- Prep for extracorporeal CPR
What do extracorporeal CPR techniques require?
Vascular access
Circuit with pump and oxygenator
Where may extracorporeal CPR be associated with improved survival?
-
Reversible cause of cardiac arrest:
- MI
- PE
- Hypothermia
- Poisoning - Few comorbidity
- Cardiac arrest witnessed
- Receive high quality CPR and ECPR
When is a resus attempt typically terminated?
- Clinical decision based on patient status and likelihood for improvement
- If asystole for >20 mins in absence of reversible cause and ongoing ALS constitute reasonable grounds for stopping further resus attempts
If shockable, usually worth continuing
How is death diagnosed after unsuccessful resuscitation?
-
Observe patient for minimum 5 mins
- no central pulse on palpation AND
- no heart sounds on auscultation - AND 1 of :
- asystole on continuous ECG
- absence of pulsatile flow using direct intra-arterial pressure monitoring
- absence of contractile activity using echo
After this assess:
1. Pupillary response
2. Corneal reflex
3. Motor response to supra-orbital pressure
Any activity prompt further 5 mins observation
What are the post event tasks for CPR?
- Ongoing care for patient and
- Allocation of roles and handover
- Document
- Communicate with relatives
- Immediate post event debrief + delayed debrief may be useful
- Ensure equipment and drug trolley replenished
- Audit forms completed
