Shock
Hypoperfusion
State of collapse and failure of the cardiovascular system that leads to inadequate circulation.
Transportation of carbon dioxide out of tissues is impaired.
Results in a dangerous buildup of waste products, which may cause cellular damage, cell injury, or death
Cardiovascular system
Pump (heart) (pump failure)
Set of pipes (blood vessels or arteries) (poor vessel function)
Contents (the blood) (low fluid volume)
When in shock: 1 or more not working properly
Pulse pressure
Systolic-diastolic bp
The amount of force the heart generates with each contraction.
A pulse pressure less than 25 mm Hg may be seen in patients with shock.
Pump failure
Cardiogenic shock
Obstructive shock (Tension pneumothorax, cardiac tamponade, pulmonary embolism)
Poor vessel function
Distributive shock (Septic, neurogenic, anaphylactic, psychogenic)
Low fluid volume
Hypovolemic shock
(hemorrhagic, nonhemorrhagic)
Cardiogenic shock
When the heart cannot maintain sufficient output to meet the demands of the body.
Backup of blood into pulmonary vessels (buildup is called pulmonary edema)
Caused by issues with contractibility of heart muscle, amount of blood to pump (preload), resistance to flow in peripheral circulation (afterload)
Obstructive shock
Mechanical obstruction that prevents an adequate volume of blood from filling the heart chambers.
Cardiac tamponade, tension pneumothorax, pulmonary embolism
Cardiac tamponade
Collection of fluid between the pericardial sac and the myocardium (pericardial effusion) becomes large enough to prevent ventricles from filling with blood.
Caused by blunt or penetrating trauma
Signs and symptoms are referred to as Beck triad (jugular vein distention, muffled heart sounds, and a narrowing pulse pressure )
Tension pneumothorax
Caused by damage to lung tissue
Air normally held within the lung escapes into the chest cavity.
The lung collapses, and air applies pressure to the organs, including the heart and great vessels.
Pulmonary embolism
A blood clot that blocks the flow of blood through pulmonary vessels
If massive:
Can result in complete backup of blood in the right ventricle
Leads to catastrophic obstructive shock and complete pump failure
Distributive shock
Widespread dilation of small arterioles, small venules, or both
The circulating blood volume pools in the expanded vascular beds.
Tissue perfusion decreases.
Septic shock
Occurs as a result of severe infections in which toxins are generated by bacteria or by infected body tissues
Toxins damage vessel walls, causing increased cellular permeability.
Vessel walls leak and are unable to contract well.
Widespread dilation of vessels, in combination with plasma loss through the vessel walls, results in shock.
High fever
Neurogenic shock
Usually the result of high spinal cord injury
Nerve impulses to blood vessels below the level of the injury are blocked.
All vessels cut off from nerve impulses will dilate, causing the blood to pool.
No tachycardia
Anaphylactic shock
Occurs when a person reacts violently to a substance to which he or she has been sensitized
Sensitization means becoming sensitive to a substance that did not initially cause a reaction.
Each subsequent exposure tends to produce a more severe reaction
Overlap of skin, circulatory system, and respiratory system (at least 2)
Urticaria (hives)
Psychogenic shock
Caused by a sudden reaction of the nervous system
Produces temporary, generalized vascular dilation
Results in fainting (syncope)
Life-threatening causes: irregular heartbeat and brain aneurysm.
Non–life-threatening events: bad news or fear/unpleasant sights (such as blood).
Hypovolemic shock
Result of an inadequate amount of fluid or volume in the circulatory system
Hemorrhagic causes and nonhemorrhagic causes
Occurs with severe thermal burns
Progression of shock
Compensated shock: early stage when the body can still compensate for blood loss
Decompensated shock: late stage when blood pressure is falling
No way to assess when effects are irreversible
Must recognize and treat shock early
Compensated shock
Agitation, anxiety, thready pulse, clammy skin, pallor, cyanosis, shallow and rapid breathing, vomiting, narrowing pulse pressure, thirst
Decompensated shock
Systolic blood pressure lower than 90
Declining mental status, altered LOC
Labored, irregular breathing
Ashen, mottled, cyanotic skin
Absent peripheral pulse
Dull eyes, dilated pupils
Poor urinary output
Expect shock if
Multiple severe fractures
Abdominal or chest injury
Spinal injury
A severe infection
A major heart attack
Anaphylaxis
Overall care for shock
Bleeding control
Patent airway
Inline stabilization (splint backboard)
Breathing and pulse check
High flow oxygen
No eating or drinking
Blankets under and over
ALS
Reassess every 5
Cardiogenic shock
Chest pain, but no nitroglycerin because bp is low
High flow o2
Ventilations if needed
Fast transport
ALS
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Chapter 10 – Patient Assessment54
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Chapter 11 – Airway Management49
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Chapter 13 – Shock31
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Chapter 18 – Neurologic Emergencies43
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Chapter 30 – Chest Injuries46
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Chapter 16 – Respiratory Emergencies64
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Chapter 17 --- Cardiovascular Emergencies60
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Chapter 21 – Allergy and Anaphylaxis15
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Chapter 26 – Bleeding46
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Chapter 29 — Head and Spine Injuries71
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Chapter 14 – BLS Resuscitation16
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Chapter 8 – Lifting and Moving Patients42
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Chapter 34 – Obstetrics and Neonatal Care89
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Chapter 35 – Pediatric Emergencies91
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Chapter 32 – Orthopaedic Injuries77
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Chapter 27 – Soft-Tissue Injuries61
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Chapter 5 – Medical Terminology50
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Chapter 12 --- Principles of Pharmacology50
