Question
In a patient with head injury, unexplained hypotension warrants evaluation of:
| A. |
Upper cervical spine
|
| B. |
Lower cervical spine
|
| C. |
Thoracic spine
|
| D. |
Lumbar spine
|
Show Answer
|
Correct Answer » B
Explanation
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|
Lower cervical spine injuries (C5–C7), particularly those involving the cervicothoracic region, disrupt descending sympathetic pathways originating from T1–L2. This leads to loss of sympathetic tone, causing vasodilation, bradycardia, and hypotension (neurogenic shock). Hence, unexplained hypotension in head injury warrants evaluation of the lower cervical spine.
Explanation of Other Options:
A. Upper cervical spine (C1–C4)
These injuries are more associated with respiratory compromise (due to phrenic nerve involvement) rather than isolated hypotension.
C. Thoracic spine
Thoracic injuries can cause neurogenic shock, especially above T6, but in trauma MCQs, lower cervical spine is more classically tested in association with head injury and hypotension.
D. Lumbar spine
Lumbar injuries do not significantly affect sympathetic outflow responsible for vascular tone; hence hypotension is unlikely due to neurogenic shock.
