Mechanisms of Injury Major mechanisms of injury are – Flexion – Hyperextension – Flexion-rotation – Extension-rotation – Compression 3
Fig. 61-5. A, Flexion injury of the cervical spine ruptures the posterior ligaments. B, Hyperextension injury of the cervical spine ruptures the anterior ligaments. C, Compression fractures crush the vertebrae and force bony fragments into the spinal canal. D, Flexion-rotation injury of the cervical spine often results in tearing of ligamentous structures that normally stabilize the spine.
Level of Injury Level of injury may be Cervical Thoracic Lumbar Paralysis of all four extremities occurs (tetraplegia [quadriplegia]) if cervical cord is involved. Paraplegia results if thoracic or lumbar cord is damaged.
Clinical Manifestations Generally direct result of trauma that causes cord compression, ischemia, edema, and possible cord transection Related to level and degree of injury Immediate post injury problems include – Maintaining a patent airway – Adequate ventilation – Adequate circulating blood volume – Preventing extension of cord damage (secondary damage) 10
Clinical Manifestations Respiratory System Respiratory complications closely correspond to level of injury. Cervical injury – Above level of C4 total loss of respiratory muscle function Mechanical ventilation is required to keep patient alive. Below level of C4 Diaphragmatic breathing if phrenic nerve is functioning Spinal cord edema and hemorrhage can cause respiratory insufficiency. Hypoventilation almost always occurs with diaphragmatic breathing. Cervical and thoracic injuries cause paralysis of – Abdominal muscles – Intercostal muscles Patient cannot cough effectively. Leads to atelectasis at or above C3 – Patient is exhausted. – Labored breathing – Endotracheal intubation/tracheostomy – Mechanical ventilation Artificial airway provides direct access for pathogens. – Important to ↓ infections Pulmonary edema may occur in response to fluid overload. 11
Clinical Manifestations Cardiovascular System Any cord injury above level T6 greatly ↓ the influence of the sympathetic nervous system – Bradycardia occurs. – Peripheral vasodilation results in hypotension. – Relative hypovolemia exists because of ↑ in venous insuficency Cardiac monitoring is necessary. Peripheral vasodilation ↓ venous return of blood to heart ↓ cardiac output IV fluids or vasopressor drugs may be required to support BP. 12
Clinical Manifestations Gastrointestinal System If cord injury is above T5, primary GI problems related to hypomotility Decreased GI motor activity contributes to development of – Paralytic ileus – Gastric distention Nasogastric tube may relieve gastric distention. 13
Clinical Manifestations Peripheral Vascular Problems Deep vein thrombosis (DVT) problem Pulmonary embolism a leading cause of death DVT assessments – Doppler examination – Measurement of legs and thigh girth 14
Diagnostic Studies CT scan may be used to assess stability of injury, location, and degree of bone injury. MRI is used where there is unexplained neurologic deficit. Neurologic examination 15
Immobilization Proper immobilization involves maintenance of a neutral position. Stabilize neck to prevent lateral rotation of cervical spine. – A blanket or towel – Hard cervical collar – Backboard Body should always be correctly aligned. Turn patient so that he or she is moved as a unit to prevent movement of spine. 16
Immobilization After cervical fusion, a hard cervical collar or a sternal– occipital– mandibular immobilizer brace can be worn. 17
Halo Vest 18 Fig. 61-11. Halo vest. The halo traction brace immobilizes the cervical spine, which allows the patient to ambulate and participate in self-care.
Fluid and Nutritional Maintenance High-protein, high-calorie diet Evaluate swallowing before starting oral feedings. If patient is not eating, cause should be thoroughly assessed. 19
Bladder and Bowel Management Constipation – Problem during spinal shock – No voluntary or involuntary evacuation of bowels occurs. – Rectal stimulant (suppository or mini-enema) inserted daily Urine retention – Loss of autonomic and reflex control of bladder and sphincter – Bladder over distention can result in reflux into kidney with eventual renal failure. – Intermittent catheterization program – Urinary tract infections 20
Cranial nerve disorders Trigeminal Neuralgia/tic douloureux-CN V Unilateral, severe, stabbing, knife-like pain in the distribution of the trigeminal nerve (ophtalmic, maxillary and mandibular,) Bell’s Palsy Facial paralysis-CN VII, pain around the ear, paralysis of motor fx of facial nerve-hearing deficit, fever, unilateral loss of taste, inability to smile, frown. Guillain-Barre Syndrome-polyneuropathy- Loss of myelin, edema and inflammation of affected nerve. Weakness of lower extremities, dysfx of sympathetic and parasympathetic NS, pain and muscle ache. Resp. failure.