PHTLS - Prehospital Trauma Life Support Prehospital Trauma Life Support Traumatic Brain Injury 1

Question 1

Under what specific circumstance does PHTLS permit controlled hyperventilation in a TBI patient?

Accepted Answer

Only when clinical signs of herniation are present, such as posturing or a blown pupil

Answer

PHTLS restricts controlled hyperventilation to a temporizing measure when herniation is suspected (e.g., posturing, fixed dilated pupil, Cushing's triad). Routine hyperventilation causes cerebral vasoconstriction that worsens ischemia in injured brain tissue.

Question 2

What minimum SpO2 value should prehospital providers maintain in a patient with suspected TBI according to PHTLS?

Accepted Answer

94%

Answer

PHTLS requires SpO2 of 94% or greater in TBI patients. Hypoxia is one of the most damaging causes of secondary brain injury, reducing oxygen delivery to already vulnerable neurons and worsening outcomes.

Question 3

Which set of findings constitutes Cushing's triad and what does it signal in a TBI patient?

Accepted Answer

Hypertension, bradycardia, and irregular respirations — indicating severely elevated ICP with impending herniation

Answer

Cushing's triad (rising blood pressure, reflex bradycardia, and irregular breathing) is a late, ominous sign that ICP has risen to a level that is compressing the brainstem. It demands immediate airway and hemodynamic intervention.

Question 4

What is the primary mechanism responsible for secondary brain injury following the initial TBI impact?

Accepted Answer

Hypoxia and hypotension causing ischemia in vulnerable, already-injured brain tissue

Answer

Secondary brain injury develops after the initial trauma and is predominantly driven by hypoxia and hypotension, both of which reduce oxygen delivery to neurons teetering on the edge of viability. Preventing these two insults is the core focus of PHTLS TBI management.

Question 5

A TBI patient has a GCS of 7 and cannot protect their airway. What is the PHTLS-recommended airway approach and ventilation rate for an adult?

Accepted Answer

Advanced airway placement with ventilation at approximately 10 breaths per minute

Answer

A GCS of 7 indicates the patient cannot protect the airway, necessitating an advanced airway (endotracheal tube or supraglottic device). The normal adult ventilation rate of ~10 breaths/min prevents inadvertent hyperventilation, which would cause harmful cerebral vasoconstriction.

PHTLS - Prehospital Trauma Life Support Practice Test

PHTLS - Prehospital Trauma Life Support Practice Test

PHTLS - Prehospital Trauma Life Support Prehospital Trauma Life Support Traumatic Brain Injury 1