BIOL 2200 MIDTERM 2: Types of shock Questions And Answers Graded A+

What type of shock leads to hypotension, hypoperfusion and then hypoxia? - Answer-Cardiogenic Shock = decreased cardiac output •Leads to hypotension to hypoperfusion and then hypoxia •Usually follows MI, but other causes as well e.g., secondary to septic shock What type of shock would occur after a large haemorrhage/ bleeding out? - Answer-Hypovolemic shock: Causes reduced cardiac output and heart rate. •Compensatory mechanisms maintain BP up to 20% blood loss •Other symptoms similar to cardiogenic shock and relate to poor blood perfusion, hypoxia and sympathetic compensation: thirst, tachycardia, cool clammy skin, metabolic acidosis etc Distributive shock occurs when: - Answer-Acute loss of muscle tone in blood vessels throughout the body i.e., vasodilation The vascular compartment enlarges, peripheral vascular resistance falls and BP falls. Blood volume may be normal. What type of shock is produced from overstimulation of the parasympathetic NS and understimulation of the sympathetic NS? - Answer-Neurogenic Shock: •The volume of the blood has not changed, but the amount of space containing the blood has increased, resulting in a decrease in BP below that required for adequate perfusion of tissues.•E.g., trauma to the spinal cord or medulla, anesthetic agents, severe pain, fainting due to emotional shock •S&S: bradycardia, warm-dry skin (opposite to other types of shock) Anaphylactic Shock occurs when: - Answer-•Immune mediated response where vasodilators (e.g., histamine) are released into general circulation •Produces vasodilation of blood vessels as well as increased capillary permeability •As in neurogenic shock the amount of space containing the blood has increased, resulting in a decrease in BP and reduced tissue perfusion. What is the main type of allergy response in anaphylactic shock? - Answer-Common causes are type I hypersensitivity reactions as covered previously (bee stings, food allergies, penicillin response etc). What type of shock is the result of an infection with micro-organism? - Answer-•Release of toxins and cytokines (e.g., TNF) stimulate overwhelming inflammatory response (similar pathogenesis to anaphylactic shock) •Vasodilation, decreased heart contractility, increased capillary permeability, loss of circulating volume causing poor tissue perfusion •Common cause of death in intensive care units Can reduced oxygen levels in blood during shock be an issue? - Answer-YES! With inefficient oxygen levels, cell switches to anaerobic respiration, which produces far less ATP. •Without sufficient ATP, the cell's sodium/potassium pump operates poorly •Sodium enters cells, water from interstitial fluid follows•Interstitial fluids then pull water out of the vascular system = decreasing blood volume •Increased hypovolemia (positive feed back loop) What the heck are vasopressors:? - Answer-Drugs that increase vasoconstriction e.g. adrenaline (epinephrine) to increase PVR and therefore BP. During shock, can metabolic acidosis occur? - Answer-Yup, decreasing pH caused by the buildup of lactic acid (from anaerobic respiration) affects enzyme systems, thus reducing cell function, repair and division Also further disrupts membranes, releasing lysozymes decreases hemoglobin-oxygen.