ALTHOUGH American Heart Association (AHA) guideline updates previously occurred every 5 years, the introduction of the 2015 guideline changes led to a more continuous review of the research. The AHA most recently published updates to its Advanced Cardiovascular Life Support (ACLS) and Pediatric Advanced Life Support (PALS) guidelines on November 5, 2018.1,2 This article covers the most current evidence-based recommendations issued by the AHA for Basic Life Support (BLS), released November 7, 2017, as well as the newly released 2018 ACLS and PALS guidelines.3 It also discusses the integration of these new guidelines into current practice.
BLS. After determining unresponsiveness, absence of breathing, and pulselessness, as is recommended in the 2015 guidelines, high-quality CPR remains the cornerstone of resuscitative efforts. Starting with compressions, push hard (at least 2 in, not to exceed 2.4 in) and fast (100 to 120 compressions/min), allowing for complete chest recoil. Minimize interruption of chest compressions (less than 10 seconds) and avoid excessive ventilation, which increases intrathoracic pressure, decreasing cardiac output.4
The updated guidelines include a change in language related to alleviating compressor fatigue. The new guidelines recommend compressors be “changed” rather than “rotated” every 2 minutes.2 The exact rationale for this change in the language is not noted, but the wording is changed in both adult and pediatric cardiac arrest algorithms. It could be surmised that “change” means simply using a different person with each compressor role change rather than rotating the compressor role among the same group of people to avoid compressor fatigue.
The 2017 updated guidelines for adult BLS also include recommendations for managing out-of-hospital cardiac arrest (OHCA), including dispatcher-assisted CPR, bystander CPR, and emergency medical services (EMS)-delivered CPR. When a lay rescuer, either trained or untrained in compression-only CPR, requires instructions from a dispatcher for an adult with OHCA, the 2017 guidelines recommend instructions for compression-only CPR. However, the lay rescuer with training in compressions and rescue breathing may provide compressions and ventilations at a ratio of 30 compressions to 2 ventilations.3 If EMS is performing CPR, recommendations include CPR with cycles of 30 compressions and 2 breaths prior to insertion of an advanced airway. As an alternative, EMS may provide asynchronous ventilations at a rate of 10 breaths/min (1 breath every 6 seconds) with continuous compressions before an advanced airway is inserted.3
ACLS. As in previously issued guidelines, the emphasis remains on high-quality CPR, oxygen administration, and rapid defibrillation as the mainstay of management in cardiac arrest due to pulseless ventricular tachycardia (pVT) and ventricular fibrillation (VF).4 The 2018 updated Adult Cardiac Arrest guidelines continue with CPR, cardiac monitor application, and rhythm interpretation. Determining if the rhythm is shockable or not determines the appropriate treatment pathway. In pVT/VF, defibrillation (first shock) using a biphasic defibrillator at an energy based on the manufacturer's recommendations, such as 120 to 200 joules (J), or a monophasic defibrillator at 360 J is indicated, followed by 2 min of high-quality CPR, I.V./I.O. insertion, and another defibrillation (second shock) if pVT/VF persists. Immediately after the second defibrillation, I.V./I.O. epinephrine (1 mg) is administered while another 2 minutes of CPR is provided, and an advanced airway is inserted to enable the use of continuous waveform capnography. I.V./I.O. epinephrine is administered every 3 to 5 minutes. If pVT/VF persists, defibrillate again (third shock). After the third shock, an antiarrhythmic is administered with 2 min of CPR.
The last section of this algorithm includes a new recommendation regarding antiarrhythmic therapy. The 2018 guidelines recommend the use of I.V./I.O. amiodarone or lidocaine in the treatment of pVT/VF that recurs or persists after three defibrillations to facilitate defibrillations and reduce the risk of pVT/VF recurrence. Research suggests that the administration of I.V./I.O. amiodarone or lidocaine to patients in persistent pVT/VF with witnessed cardiac arrest may be useful.2 The initial recommended dose of I.V./I.O. lidocaine is 1 to 1.5 mg/kg. A repeat dose of lidocaine at 0.5 to 0.75 mg/kg I.V./I.O. may be administered if required, not to exceed a total dose of 3 mg/kg. Weight-based dosing of lidocaine is recommended for patient safety. The initial I.V./I.O. amiodarone dose of 300 mg, followed by a second dose of 150 mg if needed, remains unchanged. The use of I.V./I.O. magnesium was also addressed in the 2018 ACLS update. Although not recommended routinely during cardiac arrest, magnesium may be considered in the treatment of torsades de pointes.2
Return of spontaneous circulation (ROSC). The 2018 ACLS guidelines also address the management of the adult patient who has achieved ROSC. The administration of prophylactic antiarrhythmics was also reviewed. Evidence neither supports nor refutes lidocaine administration in the first hour after ROSC, but lidocaine may be considered in specific circumstances, such as during patient transport when treatment of recurrent pVT/VF can be challenging.2 Although beta-blockers blunt the increased catecholamine effect associated with cardiac arrest, these drugs can also exacerbate heart failure and cause bradydysrhythmias. No evidence supports the use of beta-blockers after cardiac arrest from pVT or VF.2
Infants and children
BLS. The 2017 guidelines for BLS recommend compressions with rescue breaths for the infant or child in cardiac arrest. However, if rescuers are unable or unwilling to provide rescue breaths, chest compressions should be provided.3 As in the adult, the focus remains on high-quality CPR in pediatric patients. Push hard (approximately 1.5 in for infants and 2 in for children). For the patient who has reached puberty, use the adult compression depth of at least 2 in (not to exceed 2.4 in). Push fast (100 to 120 compressions/min) for infants and children. Allow for full chest recoil and avoid excessive ventilation.1 As with the adult guidelines, there is a change in language in preventing compressor fatigue with “change” of compressors rather than “rotate.”3
PALS. The updated 2018 Pediatric Cardiac Arrest Algorithm begins with continuous high-quality CPR, oxygen administration, cardiac monitor application, and rhythm interpretation. As in the adult, cardiac rhythm interpretation guides the treatment of the pediatric population. In pVT/VF, an initial defibrillation is administered at 2 J/kg, CPR is continued, and I.V./I.O. access is obtained. After 2 minutes, the rhythm is reevaluated and, if pVT/VF persists, a second defibrillation of 4 J/kg is delivered, and I.V./I.O. epinephrine is administered while CPR continues for another 2 minutes. I.V./I.O. epinephrine is administered 0.01 mg/kg every 3 to 5 minutes, and an advanced airway with continuous waveform capnography is considered. If pVT/VF persists after this 2-minute period, a subsequent defibrillation is delivered at 4 J/kg.
It is in this 2-minute section that we see some new recommendations. The 2018 Pediatric Cardiac Arrest Algorithm recommends the use of I.V./I.O. amiodarone or lidocaine in the treatment of pVT/VF that is refractory to defibrillation. As with the guidelines for adults, the objective of the antiarrhythmic administration is to facilitate successful defibrillation and decrease the risk of pVT/VF recurrence. The initial recommended dose of I.V./I.O. lidocaine is 1 mg/kg loading dose with a maintenance dose of 20 to 50 mcg/kg/min infusion. A repeat bolus is suggested if the infusion is initiated after 15 minutes of the initial dose. Another antiarrhythmic option is amiodarone at a dose of 5 mg/kg. This dose may be repeated twice if pVT/VF persists.1
Quality CPR and rapid defibrillation
As in previous AHA guidelines, high-quality CPR and rapid defibrillation remain a focal point in the resuscitation of the adult and pediatric patient in cardiac arrest due to pVT/VF. A review of the latest BLS, ACLS, and PALS guidelines includes clarification in CPR language, as well as the integration of the antiarrhythmic lidocaine in the treatment of persistent or recurrent pVT/VF in adult and pediatric patients.
Topics for future research may include new medications, a review of targeted temperature management after ROSC, and investigating better methods for monitoring CPR quality (see Education efforts). Clinician familiarity with the updated guidelines combined with better skills developed through efficient educational practices can help increase patient survival after cardiac arrest.
The AHA Education Summit steering committee suggests that instructors apply different concepts to improve how well providers learn and retain these critical skills, such as:5
- deliberate practice requiring observable key skills with minimum standards for course completion
- shorter, more frequent sessions perhaps based in the clinical setting to allow for the application of the provider's scope of practice
- an emphasis on the development of enhanced communication skills through feedback and debriefing
- improved assessment of learner competence incorporated throughout educational programs, not just at the end of the educational presentation
- the integration of new education strategies using the internet, social media, and refresher games.
Continued faculty development is possible through initial and refresher trainings based on evidence-based research.5