Shock, Multiple Organ Dysfunction Syndrome, and Burns in Adults Chapter 46 Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc.

2 Shock A condition in which the cardiovascular system fails to perfuse the tissues adequately; causes general and widespread impairment of cellular metabolism A condition in which the cardiovascular system fails to perfuse the tissues adequately; causes general and widespread impairment of cellular metabolism Many factors cause shock Many factors cause shock Defective heart function, blood volume changes, or blood vessel changes Defective heart function, blood volume changes, or blood vessel changes

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 3 Shock Many causes and clinical manifestations Many causes and clinical manifestations Shock from any cause can progress to organ failure and death Shock from any cause can progress to organ failure and death Untreated severe shock overwhelms the bodys compensatory mechanisms through positive-feedback loops that initiate and maintain a downward physiologic spiral Untreated severe shock overwhelms the bodys compensatory mechanisms through positive-feedback loops that initiate and maintain a downward physiologic spiral

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 4 Shock Classified by cause, pathophysiologic process, or clinical manifestations Classified by cause, pathophysiologic process, or clinical manifestations Cardiogenic (caused by heart failure) Cardiogenic (caused by heart failure) Neurogenic or vasogenic (alterations in smooth muscle tone) Neurogenic or vasogenic (alterations in smooth muscle tone) Anaphylactic (hypersensitivity) Anaphylactic (hypersensitivity) Septic (caused by infection) Septic (caused by infection) Hypovolemic (insufficient intravascular fluid) Hypovolemic (insufficient intravascular fluid) Traumatic (components of hypovolemic and septic) Traumatic (components of hypovolemic and septic)

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 5 Shock Patient complaints Patient complaints Weak, feeling sick, cold, hot, nauseated, dizzy, confused, afraid, thirsty, short of breath Weak, feeling sick, cold, hot, nauseated, dizzy, confused, afraid, thirsty, short of breath Blood pressure, cardiac output, and urinary output are usually decreased; the respiratory rate is usually increased Blood pressure, cardiac output, and urinary output are usually decreased; the respiratory rate is usually increased Treatment: correct or remove underlying cause and provide supportive therapy Treatment: correct or remove underlying cause and provide supportive therapy

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 6 Shock Impairment of cellular metabolism Impairment of cellular metabolism Impaired oxygen use regardless of cause Impaired oxygen use regardless of cause Aerobic to anaerobic metabolism Aerobic to anaerobic metabolism Lose ability to maintain electrochemical gradient Lose ability to maintain electrochemical gradient Sodium and chloride accumulate in the cell Sodium and chloride accumulate in the cell Water follows, thus reducing the extracellular volume Water follows, thus reducing the extracellular volume Potassium exits the cell Potassium exits the cell Activated positive-feedback loops impair further oxygen use Activated positive-feedback loops impair further oxygen use Coagulation pathway activation, decreased circulatory volume, lysosomal enzyme release Coagulation pathway activation, decreased circulatory volume, lysosomal enzyme release

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 7 Shock Impaired cellular metabolism Impaired cellular metabolism Impaired glucose use Impaired glucose use Delivery or uptake Delivery or uptake Cells shift to glycogenolysis, gluconeogenesis, lipolysis Cells shift to glycogenolysis, gluconeogenesis, lipolysis Gluconeogenesis causes proteins to be used for fuel, thus are no longer available to maintain cellular structure, function, repair, and replication Gluconeogenesis causes proteins to be used for fuel, thus are no longer available to maintain cellular structure, function, repair, and replication Toxic ammonia and urea production Toxic ammonia and urea production Metabolic acidosis Metabolic acidosis Compensatory mechanism initiated: enables cardiac and skeletal muscles to use lactic acid as a fuel source but only for limited time Compensatory mechanism initiated: enables cardiac and skeletal muscles to use lactic acid as a fuel source but only for limited time

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 8 Shock Cardiogenic (heart failure) Cardiogenic (heart failure) Cause: myocardial ischemia, MI, CHF, myocardial or pericardial infections, dysrhythmias, and drug toxicity Cause: myocardial ischemia, MI, CHF, myocardial or pericardial infections, dysrhythmias, and drug toxicity Clinical manifestations caused by inadequate perfusion to the heart and end organs Clinical manifestations caused by inadequate perfusion to the heart and end organs As cardiac output decreases, compensatory adaptive responses activated: renin-angiotensin, neurohormonal, and sympathetic nervous systems As cardiac output decreases, compensatory adaptive responses activated: renin-angiotensin, neurohormonal, and sympathetic nervous systems Cause fluid retention, systemic vasoconstriction, tachycardia Cause fluid retention, systemic vasoconstriction, tachycardia Catecholamines increase contractility and heart rate Catecholamines increase contractility and heart rate Further stress and metabolic demands on failing heart Further stress and metabolic demands on failing heart

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 9 Cardiogenic Shock

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 10 Shock Hypovolemic Hypovolemic Insufficient intravascular fluid volume Insufficient intravascular fluid volume Loss of whole blood, blood plasma, interstitial fluid, or fluid sequestration Loss of whole blood, blood plasma, interstitial fluid, or fluid sequestration Hemorrhage or burns Hemorrhage or burns Compensatory vasoconstriction, increased SVR, and afterload to improve blood pressure and perfusion to core organs Compensatory vasoconstriction, increased SVR, and afterload to improve blood pressure and perfusion to core organs If these mechanisms fail, impaired nutrient delivery and failing cellular metabolism If these mechanisms fail, impaired nutrient delivery and failing cellular metabolism

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 11 Hypovolemic Shock

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 12 Shock Neurogenic (vasogenic) Neurogenic (vasogenic) Widespread vasodilation from imbalance between parasympathetic and sympathetic simulation Widespread vasodilation from imbalance between parasympathetic and sympathetic simulation Causes persistent vasodilation and creates relative hypovolemia Causes persistent vasodilation and creates relative hypovolemia Blood volume unchanged, but amount of space containing the blood has increased, so SVR decreases drastically Blood volume unchanged, but amount of space containing the blood has increased, so SVR decreases drastically Pressure in vessels is inadequate to drive nutrients across capillary membranes; nutrient delivery to cells is impaired Pressure in vessels is inadequate to drive nutrients across capillary membranes; nutrient delivery to cells is impaired Severe pain and stress, anesthesia, and depressant drugs Severe pain and stress, anesthesia, and depressant drugs

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 13 Neurogenic Shock

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 14 Shock Anaphylactic Anaphylactic Allergen causes extensive immune and inflammatory response Allergen causes extensive immune and inflammatory response Widespread hypersensitivity reaction leading to vasodilation, peripheral pooling, relative hypovolemia Widespread hypersensitivity reaction leading to vasodilation, peripheral pooling, relative hypovolemia Extravascular effects include constriction of extravascular smooth muscle Extravascular effects include constriction of extravascular smooth muscle Constriction often causes respiratory difficulty Constriction often causes respiratory difficulty More severe due to other pathophysiologic effects More severe due to other pathophysiologic effects

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 15 Anaphylactic Shock

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 16 Shock Septic Septic Infectious processes initiate septic shock Infectious processes initiate septic shock Six most common infection sites: lungs, bloodstream, intravascular catheter, intra-abdominal, urinary tract, surgical wound Six most common infection sites: lungs, bloodstream, intravascular catheter, intra-abdominal, urinary tract, surgical wound Bacteremia, endotoxins, and exotoxins cause the host to initiate the inflammatory process Bacteremia, endotoxins, and exotoxins cause the host to initiate the inflammatory process Complement, coagulation, kinin, and cellular immunity Complement, coagulation, kinin, and cellular immunity The inflammatory response initiates and promotes widespread vasodilation The inflammatory response initiates and promotes widespread vasodilation Symptoms similar to neurogenic/anaphylactic shock Symptoms similar to neurogenic/anaphylactic shock

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 17 Multiple Organ Dysfunction Syndrome (MODS) Progressive dysfunction of two or more organ systems due to an uncontrolled inflammatory response to a severe illness or injury Progressive dysfunction of two or more organ systems due to an uncontrolled inflammatory response to a severe illness or injury Shock and sepsis are the most common causes, but can be from any injury or disease that initiates massive systemic inflammation Shock and sepsis are the most common causes, but can be from any injury or disease that initiates massive systemic inflammation Trauma, major surgery, burns, acute pancreatitis, acute renal failure, ARDS Trauma, major surgery, burns, acute pancreatitis, acute renal failure, ARDS

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 18 Multiple Organ Dysfunction Syndrome (MODS) 54% mortality rate if two organ systems are affected 54% mortality rate if two organ systems are affected Mortality rate increases to 100% with five systems failing Mortality rate increases to 100% with five systems failing

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 19 Multiple Organ Dysfunction Syndrome (MODS) Secondary MODS Secondary MODS Progressive organ dysfunction Progressive organ dysfunction Result of excessive inflammatory reaction after a latent period following the initial injury, in organs distant from the site of the original injury Result of excessive inflammatory reaction after a latent period following the initial injury, in organs distant from the site of the original injury Thought that the resulting organ trauma is caused by the host response to a second insult rather than being a direct result of the primary injury Thought that the resulting organ trauma is caused by the host response to a second insult rather than being a direct result of the primary injury Second insult mild but produces immense disproportionate response because of the previous priming of leukocytes Second insult mild but produces immense disproportionate response because of the previous priming of leukocytes Interaction of injured organs leads to a self-perpetuating inflammation Interaction of injured organs leads to a self-perpetuating inflammation

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 20 Multiple Organ Dysfunction Syndrome (MODS) Maldistribution of blood flow Maldistribution of blood flow Hypermetabolism Hypermetabolism Myocardial depression Myocardial depression Supply-dependent oxygen consumption Supply-dependent oxygen consumption Reperfusion injury Reperfusion injury

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 21 Multiple Organ Dysfunction Syndrome (MODS) Treatment Treatment Control initial inflammatory process Control initial inflammatory process Restore intravascular volume Restore intravascular volume Aimed at providing oxygen and nutrition to support failing organs Aimed at providing oxygen and nutrition to support failing organs

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 22 Burns General term describing cutaneous injury due to thermal, chemical, or electrical causes General term describing cutaneous injury due to thermal, chemical, or electrical causes Multisystem injuries with interaction of shock, inflammation, immunocompromise Multisystem injuries with interaction of shock, inflammation, immunocompromise Burns can be thermal or nonthermal Burns can be thermal or nonthermal

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 23 Burns Burn wound depth Burn wound depth First-degree burns First-degree burns Partial-thickness injury Partial-thickness injury Second-degree burns Second-degree burns Superficial partial-thickness injury Superficial partial-thickness injury Deep partial-thickness injury Deep partial-thickness injury Third-degree burns Third-degree burns Full-thickness injury Full-thickness injury Painless because nerve endings destroyed Painless because nerve endings destroyed

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 24 Burns

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 25 Burn Injury Total body surface area (TBSA) Total body surface area (TBSA) Rule of nines Rule of nines Burn injury severity is a combination of age, medical history, extent and depth of injury, and body area involved Burn injury severity is a combination of age, medical history, extent and depth of injury, and body area involved

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 26 Rule of Nines

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 27 Burn Injury Burn shock Burn shock Hypovolemic shock Hypovolemic shock Decreased cardiac contractility Decreased cardiac contractility Cellular response Cellular response Metabolic response Metabolic response Immunologic response Immunologic response Evaporative water loss Evaporative water loss

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 28 Burn Injury Burn shock Burn shock Massive edema associated with burn shock is inevitable with fluid resuscitation Massive edema associated with burn shock is inevitable with fluid resuscitation Failure to administer resuscitation fluid results in irreversible hypovolemic shock and death Failure to administer resuscitation fluid results in irreversible hypovolemic shock and death Edema in unburned as well as burned areas Edema in unburned as well as burned areas Edema often leads to mechanical airway obstruction; necessitates tracheal intubation, and increased severity of the interstitial pulmonary edema associated with inhalation injury Edema often leads to mechanical airway obstruction; necessitates tracheal intubation, and increased severity of the interstitial pulmonary edema associated with inhalation injury

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 29 Burn Shock

Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 30 Burn Shock