Student-2023 PHA3113 Patho I Shock_Coucha.pptx
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Circulatory Shock Dr. Coucha. B.Pharm. Ph.D. Associate Professor Department of Pharmaceutical Sciences South University School of Pharmacy [email protected] Office: 348 (Savannah) (912) 201-8146 Porth’s Pathophysiology, Ninth edition, Chapter 34 Porth’s Pathophysiology, Tenth edition, Chap...
Circulatory Shock Dr. Coucha. B.Pharm. Ph.D. Associate Professor Department of Pharmaceutical Sciences South University School of Pharmacy [email protected] Office: 348 (Savannah) (912) 201-8146 Porth’s Pathophysiology, Ninth edition, Chapter 34 Porth’s Pathophysiology, Tenth edition, Chapter 27 1 While coming back from work with your friend, someone jumped from behind his back and tried to get his wallet. A fight broke out, and the thief stabbed your friend in the abdomen before taking off. When the paramedics arrived, your friend was pale, sweating, and rolling restlessly on the ground. His pulse was 120 beats/minute (normal: 60-100 bpm). He was rushed to the hospital where his treatment began immediately. What type of shock could it be? 2 Learning Objectives LO1: Describe the various forms of circulatory shock LO2: Explain the etiology, clinical manifestations, compensatory mechanisms, and treatment of cardiogenic shock LO3: Explain the etiology, clinical manifestations, compensatory mechanisms, and treatment of hypovolemic shock LO4: Explain the different types of distributive shock LO5: Explain the causes and symptoms of neurogenic shock LO6: Explain the pathogenesis, manifestations, and treatments of anaphylactic shock LO7: Explain the pathogenesis, manifestations, and treatments of septic shock 3 Circulatory shock What is it? • An acute failure of the circulatory system to supply the peripheral tissues and organs of the body with an adequate blood supply, resulting in cellular hypoxia. • Most often hypotension and hypoperfusion are present • Shock may occur in the presence of normal vital signs. 4 Circulatory shock • Shock is not a specific disease but a syndrome that can occur in the course of many life-threatening traumatic conditions or disease states. I. Cardiogenic shock – an alteration in cardiac function II. Hypovolemic shock – a decrease in blood volume III. Distributive shock – excessive vasodilation with maldistribution of blood flow IV. Obstructive shock – obstruction of blood flow through the circulatory system 1: Describe the various forms of circulatory shock 5 I. Cardiogenic Shock It occurs when the heart fails to pump blood sufficiently to meet the body’s Clinically, it isdemands. defined as • Decreased CO, Hypotension, Hypoperfusion, Tissue hypoxia ses: cardial ischemia or MI, myocarditis, drugs Impaired myocardial contractility • hycardia, bradycardia Abnormalities of cardiac rhythm te mitral or aortic regurgitation, ruptured interventricular septum Cardiac structural disorder LO2: Explain the etiology, clinical manifestations, compensatory mechanisms, and treatment of cardiogenic shock 6 Pathophysiology of Cardiogenic Shock • People with cardiogenic shock have A. A decrease in SV and CO. B. Increased afterload and preload. “why?” LO2: Explain the etiology, clinical manifestations, compensatory mechanisms, and treatment 7 Compensatory Mechanisms LO2: Explain the etiology, clinical manifestations, compensatory mechanisms, and treatment I. Cardiogenic Shock Clinical Manifestations • Confusion – Neurologic changes “alterations in cognition or consciousness” • Hypotension • Oliguria – Urine output decreases. • Pale – The lips, nail beds, and skin may become cyanotic. LO2: Explain the etiology, clinical manifestations, compensatory mechanisms, and treatment 9 I. Cardiogenic Shock How to treat a patient with cardiogenic shock? • By restoring homeostasis 1. Remove causative agents if applicable e.g. arrhythmia, Pulmonary edema. 2. Restore balances carefully. 1. Improve C.O. 2. ____ workload / O2 demands 3. ____ coronary perfusion LO2: Explain the etiology, clinical manifestations, compensatory mechanisms, and treatment 10 Circulatory shock Shock is not a specific disease but a syndrome that can occur in the course of many life-threatening traumatic conditions or disease states. I. Cardiogenic shock – an alteration in cardiac function II. Hypovolemic shock – a decrease in blood volume III. Distributive shock – excessive vasodilation with maldistribution of blood flow IV. Obstructive shock – obstruction of blood flow through the circulatory system • 11 II. Hypovolemic Shock • Diminished BV leading to inadequate filling of the vascular compartment. • This is due to acute loss around 15-20% of volume. Causes External loss of • whole blood (e.g., hemorrhage) • plasma (e.g., severe burns) • extracellular fluid (e.g., severe dehydration or loss of gastrointestinal fluids with vomiting or diarrhea). LO3: Explain the etiology, clinical manifestations, compensatory mechanisms, and treatment of hypovolemic shock 12 II. Hypovolemic Shock Causes • Internal hemorrhage • Third-space losses – when extracellular fluid is shifted from the vascular compartment to the interstitial space or compartment. LO3: Explain the etiology, clinical manifestations, compensatory mechanisms, and Compensatory mechanisms of Hypovolemic Shock LO3: Explain the etiology, clinical manifestations, compensatory mechanisms, and treatment of 14 II. Hypovolemic Shock • The SS of hypovolemic shock depend on its severity and are closely related to low peripheral blood flow and excessive sympathetic stimulation. • Hypotension • Thirst • Oliguria • Changes in mentation. • Increased heart rate • Cool and clammy skin • Shallow breathing LO3: Explain the etiology, clinical manifestations, compensatory mechanisms, and II. Hypovolemic Shock The goal of treatment is to restore vascular volume • Correcting or controlling the underlying cause. • Oxygen is administered to increase oxygen delivery to the tissues. • Intravenous administration of fluids and blood. • Vasoactive medications – given only when volume deficits have been corrected yet hypotension persists. LO3: Explain the etiology, clinical manifestations, compensatory mechanisms, and 16 While coming back from work with your friend, someone jumped from behind his back and tried to get his wallet. A fight broke out, and the thief stabbed your friend in the abdomen before taking off. When the paramedics arrived, your friend was pale, sweating, and rolling restlessly on the ground. His pulse was 120 beats/minute (normal: 60-100 bpm). He was rushed to the hospital where his treatment began immediately. What type of shock could it be? 17 Circulatory shock Shock is not a specific disease but a syndrome that can occur in the course of many life-threatening traumatic conditions or disease states. I. Cardiogenic shock – an alteration in cardiac function II. Hypovolemic shock – a decrease in blood volume III. Distributive shock – excessive vasodilation with maldistribution of blood flow IV. Obstructive shock – obstruction of blood flow through the circulatory system • 18 • Mrs. Gigi a 60 year old female accidentally cut her finger while cooking. She covered the deep cut with a Band-Aid and continued cooking. After 2 days she noticed that her finger had become very red and swollen and there was a small amount of pus at the site of injury. She washed her finger and placed a new Band-Aid. A few days later, she presented to the ER with fever 40 °C, low blood pressure and tachycardia. She was complaining of growing mental confusion. What type of shock could it be? 19 III. Distributive shock Excessive vasodilation with maldistribution of BF Characterized by • Loss of blood vessel tone enlargement of the vascular compartment displacement of the vascular volume away from the heart and central circulation. • • This type of shock is also referred to as ____ volemic shock. LO4: Explain the different types of distributive shock 20 III. Distributive shock Caused by conditions that lead to loss of vascular tone: • Decrease in the sympathetic control of vasomotor tone. • The release of excessive vasodilator substances. • Direct vascular damage. There are three shock states that share the basic circulatory pattern of distributive shock: A. Neurogenic shock. B. Anaphylactic shock. C. Septic shock. LO4: Explain the different types of distributive shock 21 A. Neurogenic shock Caused by • Decreased sympathetic control of blood vessel tone – Spinal cord or brain injury. – The depressant action of drugs – General anesthesia – Hypoxia – Hypoglycemia (e.g., insulin reaction) • Fainting due to emotional causes is a transient form of impaired sympathetic outflow. 5: Explain the causes and symptoms of neurogenic shock 22 A. Neurogenic shock • • The heart rate in neurogenic shock often is ___ than normal. The skin is dry and warm • Decreased sympathetic outflow leads to – ____ vascular tone – ____ peripheral vascular resistance – _____ blood pressure 5: Explain the causes and symptoms of neurogenic shock 23 III. Distributive shock Caused by conditions that lead to loss of vascular tone: • Decrease in the sympathetic control of vasomotor tone. • The release of excessive vasodilator substances. • Direct vascular damage. There are three shock states that share the basic circulatory pattern of distributive shock: A. Neurogenic shock. B. Anaphylactic shock. C. Septic shock. 24 B. Anaphylactic Shock The most severe systemic allergic reaction. Type I allergy. https://bioresonance.com/bioresonance-and-anaphylactic-shock/ Histamine vasodilates arterioles and venules and increases capillary permeability.25 B. Anaphylactic Shock Clinical Manifestations • Apprehension • Warm or burning sensation of the skin • Itching • Urticaria (i.e., hives) • Coughing • Choking • Wheezing • Chest tightness • Difficulty in breathing 26 B. Anaphylactic Shock Anaphylactic shock often develops suddenly; death can occur within minutes unless appropriate medical intervention is promptly instituted. Treatment: • The prevention of anaphylactic shock is preferable to treatment. – Avoid foods or drugs causing it • Immediate discontinuation of the inciting agent or institution of measures to decrease its absorption (e.g., application of ice to the site of an insect bite) 27 B. Anaphylactic Shock Treatment (A,B,C) • Oxygen • Fluids • Epinephrine • Antihistamine drugs, and corticosteroids. • The person should be placed in a supine position. (NEVER move patient to sitting position) • Close monitoring of cardiovascular and respiratory function. 28 III. Distributive shock Caused by conditions that lead to loss of vascular tone: • Decrease in the sympathetic control of vasomotor tone. • The release of excessive vasodilator substances. • Direct vascular damage. There are three shock states that share the basic circulatory pattern of distributive shock: A. Neurogenic shock. B. Anaphylactic shock. C. Septic shock. 29 Septic shock It is associated with severe infection and the systemic response to infection. Sepsis is currently defined as suspected or proven infection, plus a systemic inflammatory response syndrome (e.g., fever, tachycardia, tachypnea, elevated white blood cell count, altered mental state, and hyperglycemia in the absence of diabetes) Septic shock includes patients who, despite fluid resuscitation, require vasopressor support and exhibit signs of organ dysfunction (SOFA score ≥2) Septic shock It is associated with severe infection and the systemic response to infection. Septic shock includes patients who, despite fluid SEVERE resuscitation, require vasopressor support and exhibit signs of organ dysfunction (SOFA score ≥2) infection + SYSTEMIC respon Septic shock • The normal host response to infection is recognition via pathogen recognition receptors (eg, Toll-like receptors) and immune cell migration, primarily by neutrophils, to the site of infection, where they release inflammatory mediators (TNF-α and interleukin-1). • Activated endothelial cells release nitric oxide – A potent vasodilator that acts as a key mediator of septic shock. • Pathological state of coagulation http://www.clevelandclinicmeded.com/ medicalpubs/diseasemanagement/infectious- Septic shock • Lipopolysaccharide (LPS) on the surface of microorganisms stimulate the injured endothelium to produce TF (Tissue Factor) which activates_____. • Sepsis lowers protein C, protein S, AT-III (Anti-Thrombin III) and TFI (Tissue Factor Inhibitors). Fibrin formation is ____. • LPS and TNF-alpha increase the synthesis of plasminogen activator inhibitor-1, impairing ______. Endotoxin is defined as the lipopolysaccharide (LPS) moiety contained in the outer membrane of gram-negative 33 bacteria. Septic shock Clinical Manifestations. • Hypotension and warm, flushed skin. • Abrupt changes in cognition or behavior are due to reduced cerebral blood flow and may be early indications of septic shock. • Fever and increased leukocytes are present. • An elevated serum lactate or metabolic acidosis Treatment Antibiotics Fluid administration Vaso-constrictive agents-norepinephrine A positive inotrope Administration of recombinant human activated protein C. 34 Circulatory shock Shock is not a specific disease but a syndrome that can occur in the course of many life-threatening traumatic conditions or disease states. I. Cardiogenic shock – an alteration in cardiac function II. Hypovolemic shock – a decrease in blood volume III. Distributive shock – excessive vasodilation with maldistribution of blood flow IV. Obstructive shock – obstruction of blood flow through the circulatory system • 35 IV. Obstructive shock • It results from mechanical obstruction of the flow of blood through the central circulation (great veins, heart, or lungs). • The most common cause is pulmonary embolism. • Signs of right heart failure occur • In severe or massive pulmonary embolus, fibrinolytic drugs may be used to break down the clots causing the obstruction 36 Septic shock T/F Cardiogenic and septic shock often present with a decrease in systemic vascular resistance 37 • Mrs Gigi a 60 year old female accidentally cut her finger while cooking. She covered the deep cut with a Band-Aid and continued cooking. After 2 days she noticed that her finger had become very red and swollen and there was a small amount of pus at the site of injury. She washed her finger and placed a new Band-Aid. A few days later, she presented to the ER with fever 40 °C, low blood pressure and tachycardia. She was complaining of growing mental confusion. What type of shock could it be? 38 Pair each shock type with its most common cause Shock Cause 1. Neurogenic shock A. Pulmonary embolism 2. Hypovolemic shock B. Myocardial infarction 3. Cardiogenic shock C. Spinal cord injury 4. Septic shock D. Hemorrhage 5. Anaphylactic shock E. Gram negative bacteria 6. Obstructive shock F. Insect bites 39
