The Acute Management of Spinal Injuries
Dr. Adrian Cohen MB., BS (Hons.) UNSW
Director, Immediate Assistants Pty. Ltd
|Anatomy and Physiology|
|Recognition of Spinal Injury|
|When to Transport|
B. Stabilising and Preparing the Patient for Transport
|Differentiate Hypovolaemic from Neurogenic Shock|
|Impaired Temperature Regulation|
C. Neurological Evaluation
|Diagnosis of Spinal Cord Injury|
|Documentation of the Extent of the Neurological Deficit|
D. Radiographic Examination
|Reduction of Vertebral Malalignment|
|Hyperbaric Oxygen Therapy|
|Preventing Pressure Sores|
F. Transporting the "Spinal Patient"
G. Final Transport Preparation
1. Anatomy and Physiology of the Vertebral Column and Spinal Cord
The spine is central to the skeletal system supporting the head and enclosing the spinal cord.
It consists of 33 vertebrae which are classified into five regions:
There are 7 small vertebrae in the cervical (neck) region, 12 thoracic (upper back) vertebrae, 5 lumbar (lower back) vertebrae, 5 sacral vertebrae fused together and 4 small coccygeal (tailbone) vertebrae fused together.
Running down the centre of the spine, or vertebral column, is the spinal cord. No thicker than your finger, the spinal cord is protected by the vertebrae and the surrounding muscle and ligaments.
The cord, which is extremely delicate and vital to the total functioning of the body, is made up of millions of nerves which are the communication link between the brain and all other body parts. This two way cable system picks up the incoming messages from the arms, skin, feet, etc. and transmits them to the brain. At the same time the brain also sends out messages which are transmitted to the different muscle and body functions.
The cervical nerves are responsible for movement and sensation in the upper limbs, neck and upper chest. The thoracic nerves are responsible for movement and sensation in the trunk and abdominal region. Nerves in the lumbar and sacral areas are responsible for movement and sensation in the lower limbs and bladder, bowel and sexual functions.
Damaged nerves may survive and function, but once destroyed will never recover or be replaced.
2. Recognition of Spinal Injury
The types of trauma most likely to result in spinal fracture and neurologic deficit are: automobile, motorcycle, ATV (all-terrain vehicles) and snowmobile accidents, diving injuries, cave-ins, all codes of football and falls from heights. With a head injury or in any unconscious patient, assume that there may be a spinal injury.
All head injuries should be considered spinal injuries until proven otherwise.
3. When to Transport
All patients with recognised spinal injury are candidates for transport to a Spinal Unit. Transport should take place as soon as spinal injury is recognised and immediate life-threatening problems, such as airway compromise and haemorrhage have been stabilised. Definitive care for associated injuries should, in most instances, be deferred until after transport to the Spinal Unit.
B. STABILISING AND PREPARING THE PATIENT FOR TRANSPORT
Immediately following an acute traumatic spinal cord injury, hypotension and hypoventilation may threaten life and/or increase the extent of neurological impairment.
Therefore, cardiorespiratory resuscitation and stabilisation of all other life-threatening injuries are the first steps in the treatment of acute spinal cord injured patients.
Resuscitation techniques must at times be modified to ensure that any spinal fractures remain as stable as possible, so that further neurological damage does not occur.
The aim is to transport the patient in the supine ("eyes up") position.
2. Respiratory Insufficiency
Injuries of the cervical spine are commonly associated with airway obstruction and hypoventilation. If the patient is unconscious, the tongue may passively fall backward occluding the oropharynx.
Airway patency can be restored by either the modified jaw thrust manoeuvre or by pulling the mandible forward (without inadvertently extending the neck) and then inserting an oropharyngeal airway over the tongue, whilst an assistant maintains the head in the NEUTRAL POSITION.
Hypoventilation is common in patients with thoracic injuries and loss of respiratory musculature.
Ventilatory assistance may be required in these patients, usually with tracheal intubation. Measuring and recording the patient's Vital Capacity is very helpful.
A semi-rigid cervical collar such as the Ambu or Stifneck collar should be applied as soon as cervical injury is suspected.
Steps in intubation (oral) are:
(i) Pre-oxygenation: 100%02 via bag and mask
(ii) Cricoid Pressure: during pre-oxygenation and until intubation is complete (to prevent regurgitation and gastric insufflation).
(iii) Manual Axial Support (NOT TRACTION) by an assistant holding the head in the NEUTRAL POSITION throughout.
(iv) Oro-tracheal intubation in the usual manner.
(v) Blind Nasal Intubation may be performed by a suitably experienced anaesthetist.
(vi) A surgical airway (cricothyroidotomy or tracheotomy) is an emergency alternative when intubation is not possible.
NB. A retropharyngeal haematoma associated with a major injury of the upper cervical spine may also cause upper airway obstruction and
necessitate intubation or creation of a surgical airway.
Determination of arterial blood gases via oximetry or invasive means is an essential part of the initial management of cervical and thoracic spinal cord injuries. Because of local oedema and haemorrhage, spinal cord oxygen tension may quickly fall below normal tissue requirements even without systemic hypoxaemia.
Systemic hypoxaemia may increase the severity of a spinal cord injury and attempts should be made to maintain arterial oxygen tension at or above 80mmHg
Oxygen should be delivered by a high concentration mask (50-60% unless contraindiated by chronic respiratory illness) using 100% oxygen at high flows (10-12 litres per minute). In the absence of high concentration masks or a non-rebreathing mask, a Hudson mask will suffice.
If oxygen supplementation by face mask is inadequate, careful intubation and ventilatory assistance is indicated.
The use of Hyperbaric Oxygen Therapy is an additional treatment modality aimed at preventing hypoxia at the tissue level, and should ideally be commenced WITHOUT DELAY (preferably within a few hours).
The most reliable sign of impending ventilatory decompensation is a respiratory rate greater than 35 per minute. Ventilatory assistance should be considered before the patient's respiratory rate gets this rapid.
Altered consciousness, apparent drug or alcohol intoxication, systemic hypoxaemia or hypercarbia (CO2 over 40mmHg) are also indications for assisted ventilation.
Endotracheal intubation is recommended for any patient requiring ventilatory assistance.
Radiographic evaluation of the chest is essential prior to transport of any patient with cervical or thoracic spinal cord injury, because of the
frequency of associated chest injuries, particularly pneumothorax.
If a pneumothorax is present, a chest tube must be inserted before transport.
A Heimlich valve is mandatory.
3. Circulatory Insufficiency
In cervical and thoracic spinal cord injuries, Neurogenic shock with bradycardia and hypotension are common.
In Neurogenic Shock, unlike Hypovolaemic Shock, the pulse rate is slow and of good amplitude and the skin is usually warm and dry except if the patient has been exposed to a cold environment (see 5). Tachycardia and clammy skin are seen in hypovolaemia.
Neurogenic and Hypovolaemic shock may coexist.
When this happens, Neurogenic shock exacerbates the effects of Hypovolaemic shock by disabling the vasoconstrictive reflexes that ordinarily preserve blood flow to vital organs.
Two intravenous lines, preferably 14 or 16 gauge, should be established for administration of resuscitation fluids and medications.
The maintenance of tissue perfusion cannot be over-emphasised. Spinal cord ischaemia may be due to hypotension (either from spinal shock or hypovolaemia) and can cause increased cord damage and extend the neurological deficit.
In the absence of overt Hypovolaemic shock, Hartmann's solution should be infused at a rate sufficient to maintain a systolic blood pressure of above 80mm Hg, generally 50-100ml per hour.
Pressor agents are rarely necessary and should be administered only if the central venous pressure indicates satisfactory intravascualr volume.
Neurogenic Shock with associated Hypovolaemic Shock should be treated with Normal saline or Hartmann's solution in order to increase the intravascualr volume and blood pressure. Intractable hypotension should raise the possibility of concealed internal haemorrhage.
Sinus bradycardia down to 50 associated with cervical spine cord injury does not require specific therapy.
With rates below 50, nodal or ventricular "escape" rhythms emerge that can be corrected with Atropine (0.5-1.0mg) administered as often as necessary up to 2.0mg per hour.
NB. normal quadraplegic BP range 80/40 - 100/60
DO NOT FLUID OVERLOAD: Cord oedema and reduced perfusion will result.
4. Spinal Splinting
The key to proper management of spinal trauma is to recognise that an unstable spine may exist.
Patients who arrive in the emergency department with neck already immobilised in the supine position should not be removed from the spinal splint until the extent of the injury is determined.
Inadvertent movements of the neck must be prevented during resuscitation.
The preferred means of rapidly and safely immobilising the neck from flexion and extension is to apply a semi-rigid cervical collar, such as the Ambu or Stifneck.
Lateral cervical immobilisation also needs to be maintained. This can be accomplished using blanket rolls, a blanket halo, Russell Extrication Device (R.E.D) or other type of immobilisation boards.
5. Impaired Temperature Regulation
The temperature of patients with cervical spinal cord injuries tends towards that of their immediate environment (Poikilothermia).
Body temperature should be determined regularly (orally should suffice), and in most acute cases the patient should be kept covered and warm. "Space blankets" can be of great value in these instances.
6. Internal Injuries
Loss of sensation over the thorax, abdomen or limbs is often associated with altered sensation from abdominal viscera or skeletal structures.
Thus, injuries to all but the most caudal segments of the spinal cord may abolish the spontaneous pain, tenderness to palpitation, local guarding, or generalised rigidity which are often present with other intraabdominal injuries.
Spinal cord injury alone can also produce the auscultatory and radiographic signs of ileus, within 30mins-48 hours of injury.
Patients should be transported supine with a Nasogastric Tube on continuous drainage (with suction if required).
Hypotension combined with tachycardia is seldom, if ever, attributable solely to spinal cord injury.
In the absence of other overt sources of haemorrhage, investigation of potential abdominal sources of haemorrhage by diagnostic peritoneal lavage or CT should be undertaken under these circumstances, as well as a secondary survey of other systems for missed sources.
C. NEUROLOGICAL EVALUATION
The physician that first sees the patient should document the extent of the initial neurological deficit and determine the presence of any associated injury to the vertebral column.
1. Diagnosis of Spinal Cord Injury
Signs and symptoms of spinal cord injury are usually readily apparent in the alert patient, but can be obscured by altered consciousness.
The following clues should alert the physician to the possibility of a spinal cord injury in an unconscious patient.
Similarly, a patient who moves both arms but neither legs in response to noxious local stimuli may have a spinal cord injury below the cervical level. Corroborative findings often include hypo- or areflexia and flaccidity of the paralysed limbs, a flaccid anal sphincter, or priapism.
In this condition, the thoracic cage, although stable, passively collapses with inspiration (as the diaphragm contracts) and expands with expiration (as the diaphragm relaxes) in a reversal of the normal cycle of thoracic ventilatory movements. This pattern of breathing should be looked for carefully and differentiated from bilateral flail chest, in which there will be instability of the chest wall.
2. Documentation of the Neurological Deficit
Management of spinal cord injured patients depends to a large extent upon whether the patient has a Complete or Incomplete physiological transsection of the spinal cord, and if incomplete, whether the neurological deficit is progressing or resolving with the passage of time.
The first step in determining whether the patient is deteriorating, improving or stable is to question him/her (and ambulance personnel or members of the rescue squad) about limb movement and sensation immediately after the injury.
Complete spinal cord injury is characterised by no voluntary movement and no sensation of any type below the level of the spinal cord trauma.
With any sparing at all of motor or sensory function below the level of the spinal cord injury (Incomplete lesion) the prognosis of future return of function is much more favourable.
The level of spinal cord injury is designated at the last (or highest) fully intact myotome or dermatome.
Examining physicians should identify the highest spinal cord motor segment associated with normal voluntary motor function and then determine whether any voluntary motor functions below this level has been spared.
The movements commonly used to test the integrity of spinal cord
myotomes and roots are listed below.
(Root or Myotome) Movement
C5 Abduction at the shoulder; flexion at the elbow
C6 Strong flexion at the elbow;
C7 Extension of the elbow;
C8 Grip with fingers
T1 Abduction or spreading of fingers
L2 L3 Flexion / abduction of hip;
L4 Extension of the knee
L5 Extension of the ankle and big toe
S1 Flexion of the ankle and toes
The physician should determine the upper level of sensory deficits as well as any areas of intact or spared sensation below this level. Areas commonly tested include the clavicle (C4), lateral aspect of the arm (C5), forearm and thumb (C6), middle finger (C7), little finger (C8), medial aspect of the arm (T2).
The nipples approximate the T4 level (but remember that the cervical plexus can supply this area: confirm with motor examination) and the umbilicus, T10.
The inguinal ligament or groin crease corresponds to L1, the knee to L3, the medial aspect of the dorsal of the foot to L5 and the lateral aspects to S1.
The perineum and perianal areas are innervated by S4 and S5. Anorectal sensation can be evaluated as part of the digital rectal examination.
It is of particular importance to determine any areas of intact or spared sensation on the buttocks, perineum or genitalia as this is often the only sign that a spinal cord injury is less than complete.
Reflexes are usually absent at first. Reflex activity returns from hours to weeks after injury. Reflex perianal muscle contraction usually returns before peripheral deep tendon reflexes.
Anal tone is tested by digital rectal examination, and reflex by stimulating the perianal skin, perineal reflexes by pinching the glans or base of the penis (bulbocavernosus reflex), or by tugging on the urethral catheter.
When reflexes are found to be intact, test for preservation of voluntary motor and sensory activity in the same sacral spinal cord segments.
Digital rectal examination is an important part of determining the extent of spinal cord injury. If the patient can feel the palpating finger, or if he can voluntarily contract his levator muscles around it, then he has an Incomplete lesion.
D. RADIOGRAPHIC EXAMINATION
Transport should not be delayed unduly awaiting x-rays.
In the initial evaluation of patients with signs of spinal cord injury, a detailed radiographic examination is usually much less important than a detailed neurologic examination. (The converse may be true when osseous or ligamentous spinal injury is suspected in the absence of signs of injury to the nervous system.)
Basic radiographic studies of the spine will include:
1. Cervical Spine
The full cervical spine series consist of a cross-table lateral, anterior-posterior and bilateral oblique views, and an open-mouth odontoid view.
atlantoaxial (C1-C2) articulations.
2. Thoracic Spine
Lateral and artero-posterior -- All 12 vertebrae should be visualised.
3. Lumbo-sacral Spine
Lateral and antero-posterior -- All five lumbar vertebrae and the sacrum should be visualised.
A supine antero-posterior view of the chest is important to rule out associated chest injuries. (The standard PA view obtained with the patient sitting should not be attempted.) Inspiratory and Expiratory views should be taken if pneumothorax is suspected.
Major spinal cord injuries may be present even though there is not radiographic evidence of damage to the vertebral column.
Radiographs do not show the extent of bone displacement that may have existed at the moment of injury as the result of ligamentous instability and even CT scan may
not visualise the injury.
1. Reduction of Vertebral Malalignment
A primary goal of early therapy is to decompress the spinal cord by restoring the normal sagittal diameter of the spinal canal. Reduction of a partial or complete dislocation (subluxation) may also reduce pain. Ideally, closed reduction of a cervical dislocation can be accomplished
promptly by skeletal traction in experienced hands.
Only physicians familiar with techniques of applying skeletal traction should consider carrying this out prior to transport. It may not be desirable or necessary when prompt, early transport to a Spinal Unit is available.
The cervical spine should be kept immobilised in a semi-rigid collar such as the Ambu or Stifneck until the patient arrives at the definitive treatment centre where reduction can be accomplished.
Post-traction radiographs must be taken.
Steroids have been shown to ameliorate spinal cord injury, and should be given within the first 8 hours of injury for effect.
Methyl Prednisolone (30 mg/kg) or 2 g bolus should be given as soon as possible after injury, with a further 8 g administered within the first 24 hours.
3. Visceral Paralysis
Urinary retention promotes ureterovesical reflux and overdistention of the bladder. Intermittent catheterisation is not the urinary drainage method of choice during the early post-injury period, as continuous monitoring of urine output is essential in the initial evaluation of multiple injured patients and is always necessary during transportation.
A normal Foley catheter should be inserted under meticulously sterile conditions.
Prior to the introduction of any type of urinary catheter, a rectal examination for occult blood and prostate displacement should be performed on the multiply injured male patient to rule out membranous urethral injury that could be aggravated by catheter placement.
Ileus is common following injuries of the cervical or upper thoracic spinal cord. In order to prevent aspiration of gastric contents and/or gastric dilatation that interferes with breathing, gastric decompression and drainage with a nasogastric tube is recommended.
A decompressed upper bowel will also prevent venous back-pressure from further jeopardising spinal cord perfusion. It is essential before transport.
Nasogastric tube (NGT) placement is contraindicated only in patients with severe facial injuries and/or basilar skull fractures, in which case, orogastric insertion is recommended.
4. Other Medications
Anti-emetic medication may be given immediately prior to air transport for nausea control. Small amounts of narcotic analgesic medications can be given intravenously for pain management, bearing in mind monitoring of consciousness.
Pupillary reaction should be present even when constriction is present, and dilation will still occur with raised intracranial pressure.
Medications administered should be documented in the transport record.
5. Hyperbaric Oxygen Therapy
For some cases, the delivery of oxygen under pressure in a Hyperbaric chamber may further alleviate tissue hypoxia. Most Spinal Units now have access to such a facility on-site, and it should be instituted as soon as possible after the injury, preferably within 8 hours.
6. Preventing Pressure Sores
Attention should be paid to pressure relief for the skin over bony prominences, particularly the sacrum and heels. The patient may be lifted briefly, by at least 4 persons, plus one supporting the neck, or a device such as the Jordan Frame, every two hours.
A sheepskin or foam pad, or "Sof-care" mattress (wheelchair size only), can be inserted under the sacrum by carefully lifting the pelvis. Foam or sheepskin heel padding should be used routinely.
Spinal boards should be used for the shortest, practicable periods of time, and the slats of the Jordan Frame removed between uses to prevent pressure areas.
The neck should be supported for all lifts until cervical injury has been ruled out.
Keys and money should be removed from the pockets, and ideally all clothes should be removed - cut off if necessary.
F. TRANSPORTING THE "SPINAL PATIENT"
Whenever possible, spinal injured patients should go direct to Spinal Units from the field, as time may be critical. Likewise, a speedy dispatch from the peripheral hospital is an essential link in the treatment chain.
For interhospital transfers further than 10km and within 200km of the Spinal Unit, Helicopter transfer is indicated.
The benefits are:
G. FINAL TRANSPORT PREPARATION
Before transport the following important matters should be confirmed:
|Complete Spinal Treatment Set||Lumbar Spinal Stenosis|
|NeckSafe Spinal Injury Course||The Acute Management of Spinal Injuries|
|The NeckSafe Aquatic Spinal Management Technique||Spinal Cord Anatomy|
|Spinal Cord Injuries||Spinal Cord Injury|
|Spinal Cord Injury Attorneys||Spinal Cord Injury Lawyers|
|Spinal Cord Injury Research||Spinal Decompression Therapy|
|Spinal Muscular Atrophy||Tethered Spinal Cord|
Did Heath Ledger Die of an Overdose?
Another IRG Site
©Copyright 1997 - 2013 MedicalOnline.com.au |