Brandy Tabor (CVT/VTS ( ECC)) - Shock: An Overview

Question 1

What is the common deficiency that shock patients share?

Answer 1

The common deficiency that shock patients share is a decreased delivery or utilization of Oxygen.

Question 2

What is the official definition of shock?

Answer 2

Shock is defined as an inadequate cellular energy production or decreased cellular oxygen utilization related to decreased blood flow that leads to cell death and organ failure.

Question 3

What does proper oxygen delivery (from the hemoglobin) to the tissues depend on?

Answer 3

Oxygen delivery depends on adequate perfusion of tissue.

Question 4

What occurs if tissues are not perfused with blood but the oxygen content of the blood is high?

Answer 4

Oxygen is not delivered to the cells, regardless of the oxygen content of the blood.

Question 5

What are some of the factors that affect cardiac output and blood pressure ?

Answer 5

Stretch of the vascular walls, partial pressures of oxygen and CO2 in the blood and PH

Question 6

What do changes in the MAP of a patient cause?

Answer 6

Changes in the MAP of a patient cause changes in the heart rate.

Question 7

What occurs if the MAP of a patient increases?

Answer 7

Increases in the MAP can cause bradycardia and vasodilation.

Question 8

What occurs if the MAP of a patient decreases?

Answer 8

Decreases in the MAP can cause tachycardia and vasoconstriction.

Question 9

What are changes in the Heart Rate regulated by?

Answer 9

Changes in the heart rate are medicated by baroreceptors in the heart and great vessels.

Question 10

What is the role of baroreceptors?

Answer 10

Baroreceptors do not affect the heart rate directly, but are sensitive to the stretch of vascular walls and provide feedback that can promote or inhibit vasoconstriction.

Question 11

What are the three main categories of shock?

Answer 11

The three main categories of shock are circulatory, metabolic and hypoxic.

Question 12

What is circulatory shock and why does it occur?

Answer 12

Circulatory shock occurs when there is a decrease in effective circulating blood volume as perceived by the baroreceptors.

Question 13

What is required in order to have adequate effective circulating blood volume?

Answer 13

The body must have both adequate blood volume and adequate blood pressure.

Question 14

What are the three subcategories of circulatory shock?

Answer 14

Cardiogenic, hypovolemic and distributive.

Question 15

When does cardiogenic shock occur?

Answer 15

Cardiogenic shock occurs when effective circulating volume decreases despite normal or increased blood volume and appropriate systemic resistance.

Question 16

What causes cardiogenic shock ?

Answer 16

Cardiogenic shock is caused by decreased stroke volume due to a decrease in contractility and can be seen in patients with heart failure (such as CHF, cardiac tamponade or cardiac arrhythmias)

Question 17

What are the clinical signs of cardiogenic shock

Answer 17

Clinical signs are similar to those of other types of shock, which the addition of one or all of the following: cardiac murmurs, arrhythmias, bloody froth coming from the mouth or nose, orthopnea and cyanosis.

Question 18

When does hypovolemic shock occur?

Answer 18

Hypovolemic shock occurs when blood volume is decreased through hemorrhage, third space fluid distribution, or dehydration.

Question 19

What can cause loss of whole blood?

Answer 19

Loss of whole blood may be caused by an external wound or internal bleeding, such as that seen with an intraabdominal mass. Trauma might result in a hemoperitoneum or a hemothorax. Inflammation (example: with pancreatitis) causes capillaries to become leaky, leading to fluid loss into body cavities (third spacing). Dehydration may be due to vomiting or diarrhea.

Question 20

When does distributive shock occur?

Answer 20

Distributive shock occurs when the body is unable to maintain vasoconstriction of blood vessels.

Question 21

What occurs when the body is unable to maintain vasoconstriction of blood vessels?

Answer 21

This causes systemic vasodilation, leading to hypotension despite normal cardiac function and effective circulating volume.

Question 22

What conditions can cause distributive shock ?

Answer 22

Severe anaphylaxis or any other disease process that causes severe inflammation (pancreatitis, pyelonephritis and hepatitis). Sepsis is a common cause of distributive shock as well.

Question 23

How do you know if you are dealing with septic shock?

Answer 23

Septic shock is diagnosed when hypotension secondary to sepsis is non responsive to adequate fluid resuscitation.

Question 24

What are some of the factors that contribute to septic shock ?

Answer 24

Bacterial endotoxins, cytokines, radical oxygen species released from leukocytes and nitric oxide.

Question 25

What are the clinical signs of distributive shock?

Answer 25

The clinical signs of distributive shock are different than those seen with other classifications of shock. Patients often present with strong pulses, hyperemic mucous membranes, rapid capillary refill time and elevated temperature.

Question 26

What is metabolic shock?

Answer 26

Metabolic shock is seen when oxygen delivery to the cell is normal, but the cell is unable to utilize oxygen for energy production.

Question 27

What are the causes of metabolic shock?

Answer 27

Metabolic shock is caused by hypoglycaemia, cyanide poisoning or mitochondrial dysfunction.

Question 28

What causes hypoxic shock?

Answer 28

Hypoxic shock results from impaired oxygen delivery to cells. It may be secondary to a decrease in the oxygen content of blood, as seen in anemia, decreased hemoglobin saturation or respiratory disease.

Question 29

What can also be a cause of hypoxic shock if the oxygen content of the blood is normal?

Answer 29

Oxygen off-loading might be inadequate.