Shock in Medical Science

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Questions and Answers

What is the main characteristic of the compensatory stage of shock?

Blood pressure falls below normal limits

Skin becomes warm and dry

Mitochondrial damage occurs

Blood supply is shunted from vital organs (correct)

In which stage of shock does the patient experience organ damage that is potentially irreversible?

Compensatory stage

Irreversible stage (correct)

Progressive stage

Reversible stage

What physiological response is characterized by increased heart rate and vasoconstriction in the compensatory stage of shock?

Endocrine response

Fight or flight response (correct)

Inflammatory response

Neurological response

Which of the following is NOT a consequence of shock at the cellular level?

Increased mitochondrial function Signup and view all the answers

What is the average systolic blood pressure associated with the progressive stage of shock?

Less than 90 mm Hg Signup and view all the answers

Which hormone is released in response to decreased blood flow during shock to help retain water and sodium?

Aldosterone Signup and view all the answers

Which strategy is a critical management technique applied in all types of shock?

Fluid replacement Signup and view all the answers

What critical sign indicates that the compensatory mechanisms of shock are failing?

Decreased urine output Signup and view all the answers

What is the primary focus of first-line treatment in cardiogenic shock?

Increasing oxygen supply to the heart while reducing demands Signup and view all the answers

Which condition is NOT a common cause of obstructive shock?

Septic shock Signup and view all the answers

What is the treatment approach for managing tension pneumothorax in obstructive shock?

Chest tube insertion Signup and view all the answers

Which statement best describes circulatory or distributive shock?

It results from a maldistribution or mismatch of blood flow to cells. Signup and view all the answers

What is the primary goal of medical management in septic shock?

To identify and eliminate the cause of infection Signup and view all the answers

Which of the following is NOT a classification of circulatory shock?

Hypovolemic shock Signup and view all the answers

How should intravenous lines be managed to prevent infection in high-risk patients?

Use antibiotic-coated central lines when appropriate Signup and view all the answers

What fluid types can be administered for fluid replacement in distributions shock?

Colloids, crystalloids, and blood products may be used Signup and view all the answers

What is the typical blood volume loss in hypovolemic shock ranging from 15% to 25% for a 70-kg person?

750 to 1,300 mL Signup and view all the answers

What is the primary goal of management in hypovolemic shock?

Restore intravascular volume Signup and view all the answers

In the modified Trendelenburg position, how are the lower extremities positioned?

Elevated to a 20-degree angle with straight knees Signup and view all the answers

What is the 3:1 rule in managing fluid loss?

For every 1 mL of blood loss, 3 mL of crystalloid is given Signup and view all the answers

What is a common cause of cardiogenic shock?

Myocardial infarction Signup and view all the answers

What is one of the primary goals in managing cardiogenic shock?

Limiting further myocardial damage Signup and view all the answers

Which of the following accurately describes obstructive shock?

Obstruction in blood flow due to physical causes Signup and view all the answers

Which treatment is NOT typically associated with hypovolemic shock management?

Surgical intervention Signup and view all the answers

What is one of the primary symptoms of neurogenic shock?

Flushed, warm skin that later turns cold and clammy Signup and view all the answers

What is an initial management step for a patient experiencing septic shock?

Insert a large bore peripheral venous canula for fluid resuscitation Signup and view all the answers

Which of the following is NOT a goal of early goal-directed resuscitation in septic shock?

Decrease serum lactate levels to below 2 mmol/L Signup and view all the answers

What is the cause of anaphylactic shock?

A severe allergic reaction to an antigen Signup and view all the answers

How does neurogenic shock primarily affect the body's vascular system?

Leads to massive vasodilation and relative hypovolemia Signup and view all the answers

What is a common management practice for treating neurogenic shock?

Positioning the patient properly to restore sympathetic tone Signup and view all the answers

What immediate intervention should be taken if a patient is suspected of having septic shock?

Start high flow oxygen therapy Signup and view all the answers

Which of the following is NOT a symptom of neurogenic shock?

Fever Signup and view all the answers

What is the purpose of administering epinephrine in medical management?

To provide vasoconstriction Signup and view all the answers

What medication is given to reverse the effects of histamine during an allergic reaction?

Diphenhydramine (Benadryl) Signup and view all the answers

Which of the following is crucial to perform if cardiac arrest and respiratory arrest occur?

Performing cardiopulmonary resuscitation Signup and view all the answers

What is a key nursing management strategy for patients with known allergies?

Advising the patient to carry identification of their allergens Signup and view all the answers

Systemic Inflammatory Response Syndrome (SIRS) leads to which of the following?

Overwhelming inflammatory response without infection Signup and view all the answers

What happens during Stage II of the SIRS process?

Local cytokines are released to improve local response Signup and view all the answers

What is the result if homeostasis is not restored during SIRS?

Development of a significant systemic reaction Signup and view all the answers

Which of the following best describes the consequence of cytokine release during SIRS?

Destruction rather than protection of tissues Signup and view all the answers

Study Notes

Shock

A life-threatening condition where the body isn't receiving enough blood flow.
Affects all body systems.

Cellular Effects of Shock

Cell swells and the membrane becomes more permeable.
Fluids and electrolytes leak in and out of the cell.
Mitochondria and lysosomes are damaged, leading to cell death.

Stages of Shock

Compensatory: Blood pressure remains normal, body compensates by constricting blood vessels, increasing heart rate and contractility.
- Release of catecholamines (epinephrine and norepinephrine) triggers "fight or flight" response.
- Blood is shunted from organs like skin, kidneys, and gastrointestinal tract to the brain and heart.
- Skin becomes cold and clammy, bowel sounds are reduced, and urine output decreases.
- May last minutes to hours before progressing to progressive shock if untreated.
Progressive: Body can no longer compensate for blood loss; Mean Arterial Pressure (MAP) falls below normal limits, with average systolic blood pressure under 90 mmHg.
Irreversible: Organ damage is too severe; patients don't respond to treatment and cannot survive.

Overall Management Strategies

Fluid replacement to restore intravascular volume.
Vasoactive medications to improve vasomotor tone and cardiac function.
Nutritional support to address increased metabolic needs.

Hypovolemic Shock

Occurs when intravascular fluid volume is low.
Caused by a 15% to 25% reduction in intravascular volume (loss of 750 to 1,300 mL of blood in a 70 kg person).
Average human blood volume is 5L, so losing 1L of blood represents 20% loss.

Hypovolemic Shock Management

Restore intravascular volume.
Redistribute fluid volume.
Correct the underlying cause of fluid loss as quickly as possible.
Proper positioning: Modified Trendelenburg (elevating lower extremities to 20 degrees, straight knees, horizontal trunk, slightly elevated head).
3:1 rule for crystalloid solutions: Every 1 mL of blood loss is replaced with 3 mL of crystalloid solution.

Cardiogenic Shock

Heart's ability to contract and pump blood is impaired, reducing oxygen supply to heart and other tissues.
Causes:
- Coronary: Most common, often seen in patients with myocardial infarction (heart attack) where a significant amount of left ventricular myocardium is damaged.
- Non-coronary: Metabolic problems, tension pneumothorax, conditions not affecting coronary vessels.

Cardiogenic Shock Management

Goals:
- Limit further myocardial damage.
- Improve cardiac function by increasing contractility, decreasing afterload, or both.
First-line treatment:
- Supplemental oxygen.
- Chest pain control.
- Selective fluid support.
- Vasoactive medications.
- Heart rate control (medication or pacemaker).
- Mechanical cardiac support.

Obstructive Shock

Caused by a physical obstruction blocking great vessels or interfering with the filling or emptying of the heart.
Causes:
- Cardiac tamponade: Fluid buildup in the sac surrounding the heart.
- Tension pneumothorax: Collapsed lung due to air pressure in the chest cavity.
- Pulmonary embolism: Blood clot in the lungs.

Obstructive Shock Management

Control airway.
Intubation.
Treat underlying cause:
- Chest tube for tension pneumothorax.
- Pericardiocentesis for cardiac tamponade.
- Anticoagulation for pulmonary embolism.
Isotonic fluids.

Distributive Shock

Occurs due to maldistribution of blood flow to cells, creating relative hypovolemia (reduced blood volume availability) and inadequate oxygen delivery.
Also called circulatory shock.

Distributive Shock Management

Identify and eliminate cause of infection.
Collect blood, sputum, urine, wound drainage, and catheter tip cultures.
Remove and reinsert intravenous lines.
Consider antibiotic-coated central lines to minimize infections.
Fluid replacement to correct hypovolemia.

Classification of Distributive Shock

Septic shock: Caused by sepsis and widespread infection.
Neurogenic shock: Loss of sympathetic tone (nerve signals) leading to vasodilation and pooling of blood.
Anaphylactic shock: Severe allergic reaction.

Septic Shock

Commonly affects people with compromised immunity, especially the elderly.
Triggered by release of microbes or immune mediators like tumor necrosis factor and interleukin-1.
Leads to significant decrease in tissue perfusion.

Septic Shock Management

Requires intensive monitoring in high-dependency facilities.
Early goal-directed resuscitation (within first 6 hours):
- Aim for:
  - MAP above 65 mmHg.
  - CVP 8-12 mmHg (or 12-15 mmHg if ventilated).
  - Central venous oxygen saturation (ScvO2) at least 70%.
  - Urine output at least 0.5mL/kg/hr.

Neurogenic Shock

Occurs due to loss of sympathetic tone resulting in vasodilation and blood pooling.
Symptoms:
- Low blood pressure (hypotension).
- Slow heart rate (bradyarrhythmia).
- Flushed, warm skin become cold and clammy later.
- Bluish lips and fingernails.
- Altered consciousness.

Neurogenic Shock Management

Restore sympathetic tone by addressing underlying cause (spinal cord injury, anesthesia) or proper positioning.

Anaphylactic Shock

Severe allergic reaction caused by a systemic antigen-antibody response to a foreign substance (allergen) the patient is already sensitive to.
Rapid onset and life-threatening.

Anaphylactic Shock Management

Remove the allergen.
Administer medications to restore vascular tone.
Provide emergency life support.
Medications:
- Epinephrine: To constrict blood vessels.
- Diphenhydramine (Benadryl): To reverse histamine effects.
- Albuterol (Proventil): To reverse bronchospasm.
Other interventions:
- Insert IV lines for fluids and medications.
- CPR if needed.
- Intubation or tracheotomy if airway is compromised.

Systemic Inflammatory Response Syndrome (SIRS)

Overwhelming inflammatory response without infection causing relative hypovolemia and decreased tissue perfusion.

SIRS Pathophysiology

3-stage process:
- Stage I: Local cytokine release to improve local response.
- Stage II: Small amounts of cytokines enter circulation stimulating growth factors and recruiting macrophages and platelets.
- Stage III: If homeostasis isn't restored, systemic reaction occurs, leading to cytokine release resulting in destruction rather than protection.

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Description

This quiz explores the critical condition of shock, its cellular effects, and the various stages it undergoes. Understand how the body reacts to insufficient blood flow and the implications of each stage. Test your knowledge on the physiological changes and responses during shock.