1. Chapter 32
Shock
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2. Objectives
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3. Perfusion Circulation of blood through an organ or a part of the body
Shock
Inadequate circulation of blood through an organ or a part of the body = inadequate perfusion
Perfusion is the circulation of blood through an organ or a part of the body. In order to have adequate perfusion, the heart, vessels, and the flow of blood must function properly. When the body’s tissues are adequately perfused, oxygen and other nutrients are carried to the cells of all organ systems and waste products are removed. Shock is a life-threatening condition that requires immediate emergency care.

4. Cardiogenic Shock (Pump Failure)
Possible causes:
Heart attack
Too fast or too slow heart rhythm
Injury to the heart
Other conditions that affect the heart’s ability to pump
Cardiogenic shock can occur because of a heart attack, a heart rhythm that is too fast or too slow, an injury to the heart, or other conditions that affect the heart’s ability to pump.

5. Hemorrhagic Shock (Volume Problem)
Caused by severe bleeding
Bleeding may be internal, external, or both
Shock can result if there is not enough blood for the heart to pump through the cardiovascular system. Shock caused by severe bleeding is called hemorrhagic shock. The bleeding may be internal, external, or both.

6. Hypovolemic Shock (Volume Problem)
Shock caused by:
Loss of blood (trauma)
Loss of plasma (burns)
Other body fluid
Vomiting
Diarrhea
Excessive sweating
Excessive urination
Blood is not the only type of fluid that may be lost from the body. For example, you may lose body fluid because of vomiting or diarrhea. You may lose plasma due to a burn. You can also lose fluid because of excessive sweating or urination. Shock caused by a loss of blood, plasma, or other body fluid is called hypovolemic shock.

7. Obstructive Shock
Blood flow is slowed or stopped by a mechanical or physical obstruction
Cardiac tamponade
Tension pneumothorax
Obstructive shock occurs when blood flow is slowed or stopped by a mechanical or physical obstruction. This type of shock may occur when blood collects in the sac surrounding the heart, preventing efficient cardiac contraction or when air is present in the chest due to a lung injury, putting pressure on the great vessels in the chest and limiting blood flow.

8. Distributive Shock (Pipe Problem)
Blood vessels lose ability to adjust flow of blood
Blood vessels remain enlarged
Amount of fluid in the body remains constant
Blood pools in outer areas of the body
Not enough blood to fill enlarged vessels
Vital organs are not perfused
When shock caused by container failure occurs (distributive shock), the blood vessels lose their ability to adjust the flow of blood. Instead of expanding and constricting as needed, the blood vessels remain enlarged. The amount of fluid in the body remains constant (there is no actual loss of fluid), but blood pools in the outer areas of the body. As a result, there is an inadequate amount of blood to fill the enlarged vessels, and the vital organs are not perfused.

9. Distributive Shock (Pipe Problem)
Four major causes of this type of shock are:
Injury to the spinal cord
Neurogenic shock
Severe infection
Septic shock
Severe allergic reaction
Anaphylactic shock
Psychological causes
Psychogenic shock
The four major causes of this type of shock are:
Injury to the spinal cord (neurogenic shock)
Severe infection (septic shock)
Severe allergic reaction (anaphylactic shock)
Psychological causes (psychogenic shock)

10. Shock Regardless of the type of shock:
Cells are starved for oxygen-rich blood
Without adequate oxygen:
Cells begin to break down
Waste products build up
Death may follow unless adequate perfusion is quickly restored
Regardless of the type of shock, cells are starved for adequate amounts of oxygen-rich blood. When the body’s cells and organs are not supplied with oxygen and nutrients, they begin to break down and waste products build up. Unless adequate perfusion is quickly restored, death may soon follow.

11. Stages of Shock Early (compensated) Late (decompensated)
Irreversible (terminal)
Shock occurs in stages: early (compensated), late (decompensated), and irreversible (terminal).

12. Stages of Shock Early Shock
In early shock, the body’s defense mechanisms attempt to protect the vital organs (the brain, heart, and lungs). You can recognize signs of early shock by assessing the patient’s mental status, breathing, skin color, temperature, and moisture, heart rate, strength of peripheral pulses, and capillary refill (in children younger than 6 years of age).
Early shock is usually reversible if it is recognized and the patient receives emergency care to correct the cause of the shock. If early shock is not recognized or corrected, it will progress to the next stage.

13. Stages of Shock Late Shock
When the patient’s systolic blood pressure drops to less than 90 mm Hg, late (decompensated) shock is present. In late shock, the body’s defense mechanisms lose their ability to make up for the lack of oxygenated blood. A patient in late shock looks very sick. He is usually slow to respond, confused, or may even be unresponsive. His breathing is shallow, labored, and irregular. The patient’s skin is cool, moist, and may be pale, blue, or mottled. His pulse is fast and hard to feel (thready), or may be absent in his arms and legs. The signs of late shock are more obvious than early shock, but late shock is more difficult to treat. It is still reversible if the cause of the problem is quickly corrected.

14. Irreversible Shock Body’s defense mechanisms have failed
Irregular pulse
Heart can no longer effectively pump blood
Permanent damage occurs to vital organs
Eventually:
Heart stops
Breathing stops
Death results
Irreversible shock is also called terminal shock. At this stage, the body’s defense mechanisms have failed. You will feel an irregular pulse as the patient’s heart becomes irritable and begins to beat irregularly. As shock continues, the patient’s heart rhythm becomes more chaotic and it can no longer effectively pump blood. Permanent damage occurs to the vital organs because the cells and organs have been without oxygenated blood for too long. Eventually, the heart stops, breathing stops, and death results.

15. Common Causes of Shock in Children
Trauma
Fluid loss
Infection
Anaphylaxis
Congenital heart disease
Chest wall injury

16. Indicators of Shock Altered mental status Tachycardia
Weak distal pulses
Delayed capillary refill time
Cool, mottled extremities
Indicators of shock can include altered mental status, tachycardia, weak distal pulses, delayed capillary refill time, and cool mottled extremities. Suspect shock in an infant or child who is very listless and whose muscle tone appears floppy.

17. Infants and Children
Can maintain normal blood pressure until more than half their blood volume is gone
By the time their blood pressure drops, they are close to death
Tend to compensate longer but get worse faster when compensatory mechanisms fail
Infants and children can maintain a normal blood pressure until more than half their blood volume is gone. By the time their blood pressure drops, they are close to death. Although a child in shock tends to compensate longer, he or she also gets worse faster when compensatory mechanisms fail.

18. Capillary Refill
Assess capillary refill in children younger than 6 years of age
Delayed capillary refill in an infant
Source: EMSC Slide Set (CD-ROM) Courtesy of the Emergency Medical Services for Children Program, administered by the U.S. Department of Health and Human Service's Health Resources and Services Administration, Maternal and Child Health Bureau.

19. Mottled Skin in a Child
Source: EMSC Slide Set (CD-ROM) Courtesy of the Emergency Medical Services for Children Program, administered by the U.S. Department of Health and Human Service's Health Resources and Services Administration, Maternal and Child Health Bureau.

20. Older Adults
Suspect septic shock if tachycardic and hypotensive if other causes of shock are not obvious.
Difficulty tolerating hypotension caused by hemorrhage
Beta-blockers, calcium channel blockers
Suspect septic shock in an older adult who is tachycardic and hypotensive if other causes of shock (such as hemorrhage) are not obvious. Sepsis can occur in older adults due to pneumonia or an infection from an indwelling catheter, among other causes.
Older adults have difficulty tolerating hypotension caused by hemorrhage due, in part, to inefficient blood vessel constriction. In addition, medications that the patient may be taking can prevent the patient’s heart rate from increasing, which is the body’s normal compensatory response to hemorrhage. For example, the patient may not be tachycardic if he is taking drugs such as beta-blockers and calcium channel blockers.

21. Older Adults Airway Arthritis of cervical vertebrae Dentures
Coughing often ineffective
Breathing
Higher resting respiratory rate
Lower tidal volume
Less elasticity/compliance of the chest wall
Circulation
Higher resting heart rate
Irregular pulse
When caring for an older adult, keep in mind that opening the airway can be complicated by arthritis of the cervical vertebrae. Look for dentures and remove them if they are loose or do not fit well. Coughing is often ineffective because of weakened expiratory muscles. An older adult is more likely to have a higher resting respiratory rate, lower tidal volume, and less elasticity/compliance of the chest wall than a younger adult. In addition, he is likely to have a higher resting heart rate and may have an irregular pulse.

22. Emergency Care of Shock
Scene size-up
Evaluate mechanism of injury or nature of the illness
Put on appropriate PPE
Perform a primary survey
Stabilize cervical spine if needed
Manage airway and breathing
Control all obvious external bleeding

23. Emergency Care for Shock
Place patient supine
Raise feet 6 to 12 in if no trauma present
Give oxygen
Prevent heat loss
Perform physical examination
Take vital signs, gather medical history
Rapid transport
Splint any bone or joint injuries en route
Comfort, calm, and reassure patient
Reassess at least every 5 minutes
If trauma or injury is not present or suspected, raise the feet about 6 to 12 inches (30 to 45-degrees). Do not raise the feet if the movement or the position causes the patient pain.

24. Questions?
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