In a Pt. with head injury, unexplained hypotension warrants evaluation of :
B i.e. Lower cervical spine In a patient unconscious from a head injury, or facial trauma a fracture cervical spine should be assumed untill proven otherwiseQ. Lower cervical spine fractures and dislocations are more common in incidence and are more commonly associated with spinal cord damage in comparison to upper cervical spine fractures. (d/t lesser spinal canal diameter) Due to vital functions of the nearby neurovascular structures, injuries to the upper cervical spine carry a high liklihood of death. Craniocervical injuries (occipital condyle fracture) may cause palsy of IX, X, XI and XII cranial nerves. Approximately 20% of patients with cervical trauma are hypotensive upon presentation, and most of them are lower cervical spine fractureQ. The hypotension is neurogenic in origin in about 70% of cases and is related to hypovolemia in 30% Neurogenc shock is due to loss of normal vasoconstrictive sympathetic control of the peripheral vasculature thus causing loss of normal sympathetic response to low blood pressure. In distinction from hemorrhagic shock, in which compensatory tachycardiaQ is usually present neurogenic shock results in hypotension accompanied by bradycardiaQ. Differences Neurogenic Shock Hypovolemic Shock As the result of loss of sympathetic outflow As a result of hemorrhage Hypotension Hypotension BradycardiaQ TachycardiaQ Warm extremities Cold extremeties Normal urine output Low urine output Management Treatment of neurogenic shock is pharmacological intervention to augment peripheral vascular tone Fluid - over load from excessive fluid volume administration, typically in treatment of hemorrhagic shock , can result in pulmonary edema in setting of neurogenic shock. So pressure should be restored by a combination of postural maneuvers (Trendelenburg position), judicial fluid infusion & vasopressor - administration.
Upper cervical spine
Lower cervical spine
Thoracic spine
All