Advanced Cardiac Life Support (ACLS) protocols are structured, time-critical guidelines used by healthcare professionals to manage life-threatening emergencies, such as cardiac arrest, stroke, and acute coronary syndromes. These protocols establish a systematic approach to patient care in high-stakes environments where immediate, coordinated action can significantly alter patient outcomes. ACLS training equips providers with the knowledge to perform advanced medical procedures, including advanced airway management, electrical therapy, and medication administration.
Defining the ACLS Rapid Assessment
The ACLS Rapid Assessment is the initial, systematic evaluation performed on an unstable patient to quickly identify and address immediate threats to life. Its primary purpose is to immediately manage life-threatening issues and determine the correct ACLS algorithm to follow, such as the cardiac arrest, bradycardia, or tachycardia pathways.
These protocols are based on guidelines published by the American Heart Association (AHA). The Rapid Assessment acts as a filter, allowing the medical team to prioritize interventions based on the severity of the patient’s condition. The assessment process is divided into two distinct phases: the Primary Assessment, which focuses on immediate stabilization, and the Secondary Assessment, which focuses on identifying the underlying cause.
The Primary Assessment: A-B-C-D-E
The Primary Assessment is the core of the rapid evaluation, organized around the mnemonic A-B-C-D-E, which guides the provider through a sequential check of the patient’s fundamental physiological functions. Although performed sequentially, the entire process must happen quickly, with immediate interventions taking place as problems are identified. The first step, Airway, involves ensuring the patient’s air passage is patent. This may require simple maneuvers like a head-tilt-chin-lift or the insertion of an adjunct or advanced airway device.
The next step is Breathing, where the provider assesses the adequacy of ventilation by checking the rate and quality of breaths. Supplemental oxygen is administered, and if breathing is inadequate, positive-pressure ventilation is initiated. Monitoring includes pulse oximetry to assess oxygen saturation and continuous waveform capnography. Capnography measures the amount of carbon dioxide in the exhaled breath and monitors the effectiveness of ventilation and circulation.
Circulation focuses on the heart rhythm, pulse, and perfusion, requiring the attachment of a cardiac monitor to identify the underlying rhythm. Obtaining intravenous (IV) or intraosseous (IO) access for medication administration is a parallel action performed here. For a patient in cardiac arrest, this step includes defibrillation or synchronized cardioversion for unstable rhythms, alongside high-quality chest compressions.
Disability involves a brief neurological assessment to determine the patient’s level of consciousness and responsiveness. A quick method is the AVPU scale (Alert, responsive to Voice, responsive to Pain, or Unresponsive). This step also checks for pupillary response and any signs of focal neurological deficits, which could indicate a stroke or other central nervous system event.
Finally, Exposure requires removing the patient’s clothing to allow for a full visual examination of the body. The provider looks for signs of trauma, bleeding, burns, or medical alert bracelets that might indicate an underlying condition. Temperature control is also addressed, as both hypothermia and hyperthermia can complicate resuscitation efforts.
Transitioning to the Secondary Assessment
Once immediate life threats identified in the Primary Assessment have been managed, the team transitions to the Secondary Assessment. This phase focuses on diagnostics and the search for the underlying cause of the patient’s condition, rather than immediate, hands-on interventions. The goal is to gather a focused medical history and perform a physical examination to guide definitive treatment.
A common mnemonic used for obtaining a quick history from the patient or a bystander is SAMPLE: Signs and Symptoms, Allergies, Medications, Past medical history, Last oral intake, and Events leading up to the crisis. This structured questioning provides the context necessary to understand why the emergency occurred. Concurrently, the team investigates the reversible causes of cardiac arrest, memorized using the mnemonics H’s and T’s.
H’s (Hypoxia, Volume, Acidosis, Electrolytes, Temperature)
- Hypovolemia (low blood volume)
- Hypoxia (low oxygen)
- Hydrogen ion excess (acidosis)
- Hypo-/Hyperkalemia (potassium imbalance)
- Hypothermia (low body temperature)
T’s (Mechanical and Toxic)
- Tension pneumothorax
- Tamponade (cardiac)
- Toxins
- Thrombosis (pulmonary or coronary)