Head, Spine, and Burn Trauma

Head, Spine, and Burn Trauma

1. Traumatic Brain Injury

So the primary brain injury already happened before you got there. You can't undo it. What you can still control is the secondary injury — the damage that piles on from hypoxia, hypotension, and rising pressure inside the skull. That's the whole game in TBI: not treating the impact, but preventing the second hit.

Here's the physiology behind every target. The brain sits inside a fixed, closed box. Normal intracranial pressure runs 2–12 mmHg. The mean arterial pressure pushes blood into that box, and the intracranial pressure pushes back against it. The difference between the two is what perfuses the brain. So drop the blood pressure, or raise the intracranial pressure, and perfusion falls either way. That's why hypotension damages a head-injured patient far more than it damages almost anyone else.

So your targets all come straight out of that one relationship:

• Keep oxygen saturation at 94% or above. One hypoxic episode measurably worsens the outcome. You ventilate and assist to maintain adequate oxygenation — fully within your scope.
• Avoid hypotension. Even one low systolic reading is tied to markedly worse survival. So permissive hypotension does not apply here — treat blood loss and keep the pressure up.
• Ventilate at a normal rate, targeting a normal EtCO₂ — commonly 35–45 mmHg where protocol sets that range. Waveform capnography is an AEMT-level skill, so you can watch this directly. Hyperventilating constricts cerebral vessels and cuts brain blood flow, trading a small pressure drop for real ischemia. Save it for signs of active herniation, and only as a brief bridge.
• Elevate the head about 30 degrees, if hemodynamics and spinal precautions allow it. That improves venous drainage out of the head — just don't let the collar sit so tight it blocks that drainage.
• Check the blood glucose and treat hypoglycemia. Low sugar can look exactly like a head injury on its own, and a head-injured patient who's also hypoglycemic goes downhill fast.
• Take seizure precautions. A post-traumatic seizure spikes the brain's metabolic demand at the worst possible moment.

Now here's the finding that tells you the pressure inside that box is winning: Cushing's triad. It's rising blood pressure with a widening pulse pressure, falling heart rate, and irregular respirations — the body's reflex to keep blood moving into a skull under rising pressure. It means herniation is happening. Add a blown, sluggish, or unequal pupil, plus abnormal posturing, and the picture is complete.

That triad is rising pressure and falling heart rate — the opposite of shock. So a hypotensive head-injured adult is bleeding somewhere else, until you prove otherwise.

Posturing tells you how deep the injury runs. Decorticate posturing is flexion, arms drawn toward the core — the word root gives you the picture, cortex, toward the core. It's the higher, less severe lesion. Decerebrate posturing is extension, arms straightened and rotated inward, and it's deeper and worse. A patient moving from decorticate to decerebrate is getting worse in front of you.

So the single most valuable thing you produce on a head injury is not one number. It's a trend. Run serial mental status checks — GCS or AVPU, plus pupils — and write down the time with each one. A GCS of 13 that was 15 ten minutes ago is a far more alarming finding than a GCS of 13 that's been steady the whole call.