What is the Advanced Trauma Life Support (ATLS) protocol for the initial assessment and management of a trauma patient?

ATLS Protocol for Initial Trauma Assessment and Management

Overview of the ATLS Approach

The ATLS protocol has evolved from the traditional ABCDE mnemonic to ABCDE, where represents critical/catastrophic bleeding that must be addressed immediately before airway management. 1 This modification reflects the recognition that uncontrolled hemorrhage is the leading cause of early preventable trauma deaths, accounting for 44.7-61% of deaths on the day of injury. 2

Primary Survey: ABCDE Sequence

- Critical/Catastrophic Bleeding

Control life-threatening external hemorrhage immediately before proceeding to airway assessment. 3, 4

• Apply tourniquets to stop life-threatening bleeding from open extremity injuries in pre-surgical settings 3, 4
• Use direct manual pressure for all other bleeding wounds 2
• Leave tourniquets in place until surgical control is achieved, but keep duration under 2 hours ideally to avoid complications like nerve paralysis and limb ischemia 3, 4
• Minimize time between injury and surgical intervention for patients requiring urgent bleeding control 3

A - Airway (with Cervical Spine Protection)

Establish and maintain a patent airway while simultaneously protecting the cervical spine in all trauma patients. 3, 4

• Exclude traumatic cervical injury before any airway manipulation 3, 4
• Consider oro- or nasopharyngeal airways as temporary measures 3, 4
• Perform endotracheal intubation for definitive airway protection in severe cases 3, 4

B - Breathing and Ventilation

Ensure adequate oxygenation and provide initial normoventilation if no signs of imminent cerebral herniation are present. 3, 4

• Perform immediate needle decompression for suspected tension pneumothorax with hemodynamic instability 3, 4
• Follow needle decompression with chest tube placement for definitive management 3, 4
• Use protective ventilation with low tidal volume and moderate PEEP in bleeding trauma patients at risk of acute lung injury 3, 4
• Avoid hyperventilation, as it increases mortality compared to normoventilation 3, 2
• Maintain PaCO₂ between 35-40 mmHg after stabilization in traumatic brain injury patients 3, 4

C - Circulation and Hemorrhage Control

Assess the extent of traumatic hemorrhage using mechanism of injury, patient physiology, anatomical injury pattern, and response to initial resuscitation. 1, 3

ATLS Classification of Hemorrhagic Shock:

• Class I: Blood loss up to 750 ml (15% blood volume) 4
• Class II: Blood loss 750-1500 ml (15-30% blood volume) - pulse >100-120, respiratory rate >20-30, urine output <30 mL/hour, anxiety 4, 2
• Class III: Blood loss 1500-2000 ml (30-40% blood volume) - confusion, requires immediate surgical intervention 4, 2
• Class IV: Blood loss >2000 ml (>40% blood volume) - imminent death without immediate hemorrhage control 4, 2

Hemodynamic Assessment:

Define instability as: systolic BP <90 mmHg, heart rate >120 bpm, cool/clammy skin, altered consciousness, and/or shortness of breath 3

Critical pitfall: Young, healthy patients maintain normal blood pressure through vasoconstriction and tachycardia even with Class II hemorrhagic shock (15-30% blood volume loss), so relying solely on blood pressure is misleading. 2

Response to Initial Fluid Resuscitation (2000 mL crystalloid in adults, 20 mL/kg in children):

• Rapid Response: Vital signs return to normal and remain stable - continue monitoring 4, 2
• Transient Response: Initial improvement followed by deterioration - requires immediate surgical intervention 4, 2
• Minimal or No Response: Ongoing instability despite resuscitation - requires immediate surgical intervention 4, 2

Additional Assessment Tools:

• Use shock index (SI = heart rate/systolic BP) ≥0.9-1.0 to predict need for massive transfusion 1
• Base deficit <-6 mEq/L or lactate >2.2-4 mmol/L significantly predict major hemorrhage and mortality even when blood pressure appears normal 2
• Mechanism of injury: falls >6 meters (20 feet), high-energy deceleration, high-velocity gunshot wounds indicate high risk 1

D - Disability (Neurological Status)

Rapidly assess neurological status using Glasgow Coma Scale. 3, 4

• Control seizures if present, especially in traumatic brain injury 3, 4
• Target systolic blood pressure >110 mmHg to ensure adequate cerebral perfusion 3
• Recognize that secondary brain injury from hemorrhage-induced hypotension and coagulopathy creates a "vicious circle" that worsens outcomes 2

E - Exposure and Environmental Control

Completely undress the patient to facilitate thorough examination while preventing hypothermia. 3, 4

Hypothermia Management Protocol:

• Level 1 (Temp >36°C): Passive and active external warming with two warm blankets; monitor temperature every 15 minutes 4
• Level 2 (Temp 32-36°C): Add heating pads, radiant heaters, warming blankets, and humidified gases; monitor temperature every 5 minutes 4
• Level 3 (Temp <32°C): Implement invasive strategies including cavity lavage or extracorporeal circuits 4

Secondary Survey

Perform a comprehensive head-to-toe examination only after completing the primary survey and stabilizing life-threatening conditions. 3, 4

• Obtain relevant medical history using the AMPLE approach: Allergies, Medications, Past medical history, Last meal, Events/Environment related to injury 3, 4
• Reassess vital signs frequently 3, 4
• Observational studies demonstrate that healthcare professionals often skip or incompletely perform both primary and secondary survey tasks, highlighting the need for systematic adherence 1

Critical Time-Dependent Factors

Every additional minute of pre-hospital time increases mortality risk, with a 1% mortality increase per minute of scene time and a 2% mortality increase per minute of response time in penetrating trauma. 2

• More than 50% of fatal trauma outcomes occur within 24 hours, with 34.5% classified as potentially preventable by early hemorrhage control 2
• The majority of hemorrhagic deaths (74.3%) occur either prehospital or within the first hour of hospital arrival 2

Common Pitfalls to Avoid

• Relying solely on blood pressure: Patients may maintain "normal" blood pressure despite significant ongoing blood loss due to compensatory mechanisms 4, 2
• Failing to recognize transient responders: These patients initially stabilize with fluid resuscitation but later decompensate and require immediate surgical intervention 3, 4
• Delaying definitive intervention: Unstable patients with identified bleeding sources require immediate surgical control 3, 4, 2
• Hyperventilating trauma patients: This increases mortality compared to normoventilation 3, 2
• Prolonged tourniquet placement: Keep duration as short as possible to avoid nerve paralysis and limb ischemia 3, 4
• Neglecting thorough examination: When other conditions like intoxication are present, physical trauma may be overlooked 3, 4

Evidence-Based Implementation

The ATLS protocol represents a standardized, systematic approach developed by the American College of Surgeons that has become the international standard for initial trauma assessment and management. 5 Implementation of structured checklists has been shown to significantly improve ATLS task performance, with greater completion rates (OR = 2.66 for primary survey, OR = 2.47 for secondary survey) and faster task completion. 6 However, adherence to ATLS guidelines remains variable in clinical practice, emphasizing the need for continuous training and systematic protocols. 1, 7