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SPINAL SHOCK When a spinal cord injury is caused due to trauma, the body goes into a state known as spinal shock. While spinal shock begins within a few minutes of the injury, it make take several hours before the full effects occur. During spinal shock the nervous system is unable to transmit signals, some of which may return once spinal shock has subsided, the time spinal shock lasts for is approximately 4-6 weeks following the injury. In some rare cases spinal cord shock can last for several more months. The loss of these signals will effect the persons movement, sensation and how well the body’s systems function. Often the persons loss of movement and sensation below the level of the spinal cord injury may appear complete soon after the injury. This may mask the real extent of the damage. Usually, over the first few weeks the some of body systems adjust to the effects of the injury and their function improves. Therefore, during this time and the early stage of ANY new injury it is unlikely that an accurate prediction of any recovery or permanent paralysis can be made. Treatment begins with the emergency medical personnel who make an initial evaluation and immobilise the patient for transport. Immediate medical care within the first 8 hours following injury is critical to the patient's recovery. Nowadays there is much greater knowledge about the moving and handling of spinal injury patients. Incorrect techniques used at this stage could worsen the injuries considerably. When injury occurs and for a period of time thereafter, the spinal cord responds by swelling. Treatment starts with steroid drugs, these can be administered at the scene by an air ambulance Doctor or trained paramedic. These drugs reduce inflammation in the injured area and help to prevent further damage to cellular membranes that can cause nerve death. Sparing nerves from further damage and death is crucial. Each patient's injury is unique. Some patients require surgery to stabilise the spine, correct a gross misalignment, or to remove tissue causing cord or nerve compression. Spinal stabilisation often helps to prevent further damage. Some patients may be placed in traction and the spine allowed to heal naturally. Every injury is unique as is the course of post injury treatment that follows. When a spinal cord is damaged by trauma, it also causes a concussion like injury to spinal cord which leads to total sensory and motor power loss and loss of all reflexes for initial some period which is followed by then gradual recovery of reflexes. This state of sensory and motor loss along with total loss of reflexes following trauma is known as spinal shock. Spinal shock begins within a few minutes of the injury, it make take several hours before the full effects occur. During spinal shock the nervous system is unable to transmit signals from brain to end organs as they are not routed by the spinal cord. Usually the spinal shock recovers within 24 hours but may last over few weeks in less common cases. In some rare cases spinal cord shock can last for several more months. Significance of Spinal Shock The loss of these signals will result in loss of movements, sensations other body function. Complete loss of movement and sensation below the level of the spinal cord injury makes it difficult to assess the exact quantum of injury. Thus it is not possible to find the level, extent and severity of injury as patients would show compete neural loss. The only way to find that is to wait for spinal shock to recover. Over the first few weeks the some of body systems adjust to the effects of the injury and their function improves. Therefore, during this time it is unlikely that an accurate prediction of any recovery or permanent paralysis can be made. Pathophysiology of spinal Shock Exact cause of the spinal shock is not known. It is thought that acute injury causes depolarization of axons due to transfer of kinetic energy. There are three phases of spinal shock Phase 1 A complete loss or weakening of all reflexes below the level of spinal cord injury. This phase lasts for a day. The neurons involved in various reflex arcs the neural input from the brain due to spinal concussion become hyperpolarized and less responsive. Phase 2 It occurs over the next two days, and is characterized by the return of some, but not all, reflexes. The first reflexes to reappear are polysynaptic in nature, such as the bulbocavernosus reflex. Bulbocavernosus reflex can be checked by noting anal sphincter contraction in response to squeezing the glans penis or tugging on the Foley. It involves the S1, S2, S3 nerve roots and is spinal cord mediated reflex. Its presence signals the end of spinal shock. Monosynaptic reflexes, such as the deep tendon reflexes, are not restored until Phase 3. The reason reflexes return is the hypersensitivity of reflex muscles following denervation — more receptors for neurotransmitters are expressed and are therefore they are easier to stimulate. Phases 3 and 4 are characterized by hyperreflexia, or abnormally strong reflexes usually produced with minimal stimulation following sprouting of interneurons and lower motor neurons below the injury begin to attempt to reestablishment of synapses. Identification of Spinal Shock Paralysis, hypotonia & areflexia, and at its conclusion there may be hyperreflexia, hypertonicity, and clonus. Return of reflex activity below level of injury (such as bulbocavernosus) indicates end of spinal shock. Spinal shock does not occur in the lesions that occur below the cord, and therefore, lower lumbar injuries should not cause spinal shock . If bulbocaveronsus reflex in such cases may indicate a cauda equina injury Return of the of bulbocavernous reflex signifies the end of spinal shock, and if injury is complete, any further neurological improvement will be minimal. Complete absence of distal motor function or perirectal sensation, together with recovery of the bulbocavernosus reflex, indicates a complete cord injury, and in such cases it is highly unlikely that significant neurologic damage will return. Neurogenic shock Neurogenic shock is a type of shock caused by the sudden loss of the autonomic nervous system signals to the smooth muscle in vessel walls. This results in loss of background sympathetic stimulation, which is responsible for maintenence of tone of blood vessels. As a result of loss of vascular tone, the vessels suddenly relax resulting in a sudden decrease in peripheral vascular resistance and decreased blood pressure. Causes Failure of the autonomic nervous system can arise from Regional anesthetics Injuries to the spinal cord (cervical spine and upper thoracic spine) Administration of autonomic blocking agents. Pathophysiology The cardiac output decreases because the venule and small veins lose tone. Blood pools in the periphery and blood pressure falls. In the normal situation, a reflex increase in heart rate will occur to compensate for the peripheral pooling of blood. However, in neurogenic shock, the sympathetic pathways to the heart are blocked or damaged by trauma, resulting in a bradycardia. Symptoms and Signs The surroundings leading to shock are very important in making the diagnosis. Diagnosis of neurogenic shock rests on knowledge of the history surrounding the onset of shock. The features suggesting neurogenic shock are Hypotensio Bradycardia Warm, dry extremities Peripheral vasodilation and venous pooling Poikilothermia ( Cold Body) Decreased cardiac output (with cervical or high thoracic injury) Treatment Fluid challenge Vasopressors Beta-blockers can be implemented. Phenylephrine or norepinephrine can be used