Resuscitation
INTRODUCTION
Without intervention, cardiac arrest may lead to permanent neurological injury after just three minutes. The interventions that contribute to a successful outcome after a cardiac arrest can be conceptualized as a chain – the Chain of Survival (Fig. 47.1).
The four links in this chain are:
Early recognition – to potentially enable prevention of cardiac arrest – and call for help
Early cardiopulmonary resuscitation (CPR)
PREVENTION
Guidelines for Prevention of In-Hospital Cardiac Arrest (Resuscitation Council (UK))
1. Place critically ill patients, or those at risk of clinical deterioration, in areas where the level of care is matched to the level of patient sickness.
2. Monitor such patients regularly using simple vital sign observations (e.g. pulse, blood pressure, respiratory rate, conscious level, temperature and SpO2). Match the frequency and type of observations to the severity of illness of the patient.
3. Use an early warning score (EWS) system or ‘calling criteria’ to identify patients who are critically ill, at risk of clinical deterioration or cardiopulmonary arrest, or both.
4. Use a patient vital signs chart that encourages and permits the regular measurement and recording of vital signs and, where used, early warning scores.
5. Ensure that the hospital has a clear policy that requires a timely, appropriate, clinical response to deterioration in the patient’s clinical condition.
6. Introduce into each hospital a clearly identified response to critical illness. This will vary between sites, but may include an outreach service or resuscitation team (e.g. medical emergency team (MET)) capable of responding to acute clinical crises. This team should be alerted, using an early warning system, and the service must be available 24 hours a day.
7. Ensure that all clinical staff are trained in the recognition, monitoring, and management of the critically ill patient, and that they know their role in the rapid response system.
8. Empower staff to call for help when they identify a patient at risk of deterioration or cardiac arrest. Use a structured communication tool to ensure effective handover of information between staff (e.g. SBAR – Situation-Background-Assessment-Recommendation).
9. Agree a hospital do-not-attempt-resuscitation (DNAR) policy, based on current national guidance. Identify patients who do not wish to receive CPR and those for whom cardiopulmonary arrest is an anticipated terminal event for whom CPR would be inappropriate.
10. Audit all cardiac arrests, ‘false arrests’, unexpected deaths, and unanticipated intensive care unit admissions, using a common dataset. Audit the antecedents and clinical responses to these events. All hospitals should consider joining NCAA (http://www.resus.org.uk/pages/NCAA.htm).
CARDIOPULMONARY RESUSCITATION
The sequence of actions and outcome depends on:
Location – out-of-hospital versus in-hospital; witnessed versus unwitnessed; monitored versus unmonitored.
Skills of the responders – in some public places staff may be trained in CPR and defibrillation. All healthcare professionals should be able to recognize cardiac arrest, call for help, and start resuscitation.
Number of responders – single responders must ensure that help is coming. If other staff are nearby, several actions can be undertaken simultaneously.
Equipment available – AEDs are available in some public places. In hospital, ideally, the equipment used for CPR (including defibrillators) and the layout of equipment and drugs should be standardized throughout the hospital. AEDs should be considered for clinical and non-clinical areas where staff do not have rhythm recognition skills or rarely need to use a defibrillator.
Response system to cardiac arrest and medical emergencies – outside hospital the EMS should be summoned. In hospital, the resuscitation team can be a traditional cardiac arrest team (called when cardiac arrest is recognized) or a MET.
ADVANCED LIFE SUPPORT
Arrhythmias associated with cardiac arrest are divided into two groups: shockable rhythms (VF/VT) and non-shockable rhythms (asystole and PEA). The principle difference in management is the need for attempted defibrillation in patients with VF/VT. Subsequent actions, including chest compression, airway management and ventilation, vascular access, injection of adrenaline, and the identification and correction of reversible factors, are common to both groups. The ALS algorithm (Fig. 47.3) provides a standardized approach to the management of adult patients in cardiac arrest.
FIGURE 47.3 The advanced life support algorithm (adapted from 2010 Resuscitation Guidelines (Resuscitation Council UK)).
Shockable Rhythms (VF/VT)
Sequence of Actions
If VF/VT is confirmed, charge the defibrillator while another rescuer continues chest compressions.
Once the defibrillator is charged, pause the chest compressions, quickly ensure that all rescuers are clear of the patient and then give one shock. The person doing compressions, or another rescuer may deliver the shock. This sequence should be planned before stopping compressions.
Resume chest compressions immediately (30:2) without reassessing the rhythm or feeling for a pulse.
Continue CPR for 2 min, then pause briefly to check the monitor:
On completion of CPR for 2 min, pause briefly to check the monitor:
If intravascular (i.v./intraosseous) access has been obtained, give adrenaline 1 mg and amiodarone 300 mg once compressions have resumed. On completion of CPR for 2 min, pause briefly to check the monitor:
Give a further (4th) shock; resume CPR immediately and continue for 2 min.
Give adrenaline 1 mg with alternate cycles of CPR (i.e. approximately every 3–5 min).
If organized electrical activity is seen during this brief pause in compressions, check for a pulse.
If a pulse is present, start post-resuscitation care.
If no pulse is present, continue CPR and switch to the non-shockable algorithm.
If asystole is seen, continue CPR and switch to the non-shockable algorithm.
Defibrillation Strategy
Pads Versus Paddles: Self-adhesive defibrillation pads have practical benefits over hand-held paddles for routine monitoring and defibrillation and are much preferred to standard defibrillation paddles. Use of self-adhesive pads enables the operator to defibrillate the patient from a safe distance and to deliver a shock more rapidly than with paddles.
Safe Use of Oxygen: In an oxygen-enriched atmosphere, sparks from defibrillator paddles applied poorly can cause a fire. The use of self-adhesive defibrillation pads instead of manual paddles reduces the risk of sparks occurring.
Remove any oxygen mask or nasal cannulae and place them at least 1 m away from the patient’s chest during defibrillation.
Leave the ventilation bag connected to the tracheal tube or other airway adjunct. Alternatively, disconnect the ventilation bag from the tracheal tube and move it at least 1 m from the patient’s chest during defibrillation.
Single Versus Three-Shock Strategy: If defibrillation is attempted immediately after the onset of VF, it is unlikely that chest compressions will improve the already very high chance of ROSC associated with second or third shocks (i.e. myocardial levels of oxygen and adenosine triphosphate are likely to be adequate for the first minute or so). Thus, if VF/VT occurs during cardiac catheterization or in the early post-operative period after cardiac surgery (when chest compressions could disrupt vascular sutures), consider delivering up to three-stacked shocks before starting chest compressions. This three-shock strategy may also be considered for an initial, witnessed VF/VT cardiac arrest if the patient is already connected to a manual defibrillator – this situation will exist perioperatively if defibrillation pads were applied before induction of anaesthesia.
Defibrillation Energy: All modern defibrillators deliver shocks with a biphasic waveform. The initial biphasic shock should be at least 150 J. Because of the lower efficacy of monophasic defibrillators for terminating VF/VT, the recommended initial energy level for the first shock using a monophasic defibrillator is 360 J. If an initial shock has been unsuccessful, deliver the second and subsequent shocks with a higher energy level if the defibrillator is capable of delivering a higher energy. Manufacturers should display the effective waveform energy range on the face of the biphasic device. If you are unaware of the effective energy range of the device, use 200 J for the first shock.
Non-Shockable Rhythms (PEA and Asystole)
Sequence of Actions for PEA
Start CPR 30:2 and inject adrenaline 1 mg as soon as intravascular access is achieved.
Continue CPR 30:2 until the airway is secured, then continue chest compressions without pausing during ventilation.
Identify and correct any reversible causes of PEA.
Recheck the patient after 2 min: