Clinical Scenarios, Critical Thinking
Questions & Answers for NAEMT Prehospital
Trauma Life Support
PHTLS 10TH EDITION STUDY GUIDE 2026 - COMPREHENSIVE EXAM
• This study material provides clinically relevant scenarios and critical thinking
questions aligned with NAEMT PHTLS 10th Edition standards for prehospital
trauma care
• Study approach: Work through each question systematically, review EXPERT
RATIONALE thoroughly to understand the clinical reasoning, and focus on bridging
assessment findings to appropriate trauma management decisions
SECTION 1: SCENE SAFETY AND INITIAL ASSESSMENT
1. You arrive at a motor vehicle collision scene with downed power lines near
the vehicles. What is your FIRST action?
A) Proceed to the vehicles to assess patients
B) Establish a perimeter and do not enter until utilities confirm scene safety
C) Move the downed lines away from the patient area
D) Assess patients from a distance of 10 feet
E) Call for fire department to remove the lines
**CORRECT ANSWER: *** B) Establish a perimeter and do not enter until utilities
confirm scene safety ***
EXPERT RATIONALE: Scene safety is the absolute priority in trauma care. Downed
power lines present an electrocution hazard to providers and patients alike. You
must establish a safety perimeter, prevent entry, and contact utilities to de-energize
the lines before any patient care is initiated. Approaching the scene or moving lines
without proper safety clearance violates fundamental scene safety principles and
puts you and your crew at risk.
,2. During your scene size-up at a stabbing incident, you notice an agitated
crowd and the potential perpetrator is still present. What should you do?
A) Enter the scene with police standing by
B) Wait for law enforcement to secure the scene before entering
C) Send one paramedic in while others maintain scene security
D) Request additional ambulances to handle multiple entries
E) Treat the patient from the street
**CORRECT ANSWER: *** B) Wait for law enforcement to secure the scene before
entering ***
EXPERT RATIONALE: Scene safety takes precedence over patient care. An unstable
scene with a potential threat requires law enforcement to secure the area before
EMS enters. No patient is so critical that providers should enter an unsafe scene.
Once law enforcement confirms the scene is secure, you can proceed with
assessment and treatment. This protects both you and your crew.
3. You are responding to a report of a patient involved in a structure fire. The
building is actively burning with heavy smoke and flames visible. What is your
appropriate response?
A) Enter with full protective equipment to locate the patient
B) Establish a staging area outside the dangerous perimeter and await building all-
clear
C) Send the most experienced paramedic in first to scout
D) Use ventilation techniques to create a safe entry point
E) Position ambulances at the rear exit
**CORRECT ANSWER: *** B) Establish a staging area outside the dangerous
perimeter and await building all-clear ***
,EXPERT RATIONALE: Active structural fires are outside the scope of standard EMS
operations. Your role is to establish a medical staging area at a safe distance and
await notification from fire command that patients have been extracted and the
scene is clear. Entering an actively burning structure without specialized rescue
training and equipment is extremely dangerous and violates scene safety protocols.
4. At a multi-vehicle collision with hazardous materials placards visible, what
is your first responsibility?
A) Identify the specific chemical and proceed with decontamination
B) Establish scene control at an appropriate distance per hazmat guidelines
C) Evacuate all nearby residents immediately
D) Request additional ambulances before scene assessment
E) Don protective equipment and approach vehicles
**CORRECT ANSWER: *** B) Establish scene control at an appropriate distance per
hazmat guidelines ***
EXPERT RATIONALE: Hazmat scenes require establishment of perimeter control
zones per incident command. You must identify placards and reference
appropriate distances based on the substance involved. Request hazmat specialists
to manage the chemical/biological threat. Do not approach or attempt
decontamination without proper hazmat team involvement. Patient care is
deferred until the scene is declared safe by competent authorities.
5. You respond to a residential scene where a patient fell from a ladder. A
family member states the patient fell into the basement where there is
currently standing water. What is your concern?
A) The patient may have multiple fractures
B) Hypothermia from water submersion
C) Potential electrocution hazard from submerged electrical lines or appliances
, D) Contaminated water exposure
E) Difficulty with extrication
**CORRECT ANSWER: *** C) Potential electrocution hazard from submerged
electrical lines or appliances ***
EXPERT RATIONALE: Standing water in basements often contains electrical hazards
from submerged wiring, outlets, or appliances. Before entering or allowing patient
movement, you must assess for electrical hazards. Contact the utility company to
cut power if electrical hazards are suspected. Only after ensuring no electrocution
risk should rescue and patient care proceed. This is a critical safety consideration
that supersedes patient treatment timing.
6. During your approach to a motor vehicle collision, you observe a patient
slumped in the driver's seat with the engine still running and windows up.
What should you do FIRST?
A) Open the door and perform patient assessment immediately
B) Ensure your safety by turning off the engine through the open window
C) Perform a rapid scene assessment for hazards including carbon monoxide risk
D) Call for additional resources before approach
E) Request the fire department to stabilize the vehicle
**CORRECT ANSWER: *** C) Perform a rapid scene assessment for hazards
including carbon monoxide risk ***
EXPERT RATIONALE: This scenario presents multiple hazards: running engine with
windows closed creates carbon monoxide (CO) accumulation, which can affect both
the patient and rescuers. You must recognize this hazard during scene assessment.
Ventilate the vehicle, turn off the engine, and allow CO to clear before prolonged
patient contact. If the patient shows signs of altered mental status, carbon
monoxide poisoning must be considered. Scene assessment precedes patient
contact.