MindMap Gallery Pathophysiology Shock
This is a mind map about shock in "Pathophysiology", which mainly includes the characteristics of several common shocks, The development process of shock (hemorrhagic shock), the pathogenesis of shock, Principles of prevention and treatment, causes and classification of shock, etc.
Edited at 2023-12-18 17:06:49One Hundred Years of Solitude is the masterpiece of Gabriel Garcia Marquez. Reading this book begins with making sense of the characters' relationships, which are centered on the Buendía family and tells the story of the family's prosperity and decline, internal relationships and political struggles, self-mixing and rebirth over the course of a hundred years.
One Hundred Years of Solitude is the masterpiece of Gabriel Garcia Marquez. Reading this book begins with making sense of the characters' relationships, which are centered on the Buendía family and tells the story of the family's prosperity and decline, internal relationships and political struggles, self-mixing and rebirth over the course of a hundred years.
Project management is the process of applying specialized knowledge, skills, tools, and methods to project activities so that the project can achieve or exceed the set needs and expectations within the constraints of limited resources. This diagram provides a comprehensive overview of the 8 components of the project management process and can be used as a generic template for direct application.
One Hundred Years of Solitude is the masterpiece of Gabriel Garcia Marquez. Reading this book begins with making sense of the characters' relationships, which are centered on the Buendía family and tells the story of the family's prosperity and decline, internal relationships and political struggles, self-mixing and rebirth over the course of a hundred years.
One Hundred Years of Solitude is the masterpiece of Gabriel Garcia Marquez. Reading this book begins with making sense of the characters' relationships, which are centered on the Buendía family and tells the story of the family's prosperity and decline, internal relationships and political struggles, self-mixing and rebirth over the course of a hundred years.
Project management is the process of applying specialized knowledge, skills, tools, and methods to project activities so that the project can achieve or exceed the set needs and expectations within the constraints of limited resources. This diagram provides a comprehensive overview of the 8 components of the project management process and can be used as a generic template for direct application.
shock
Characteristics of several common shocks
hemorrhagic shock
The initial stage of shock is insufficient effective circulating blood volume caused by blood loss.
Distinct microcirculatory staging and typical clinical manifestations
Susceptible to acute renal failure and enterogenic endotoxemia
septic shock (septic shock)
Initiation link - all three
Can easily cause systemic inflammatory response syndrome
According to hemodynamics, it is divided into: hyperdynamic shock and hypodynamic shock.
anaphylactic shock
The initial stage of shock
Allergic reactions cause extensive dilation of blood vessels and increase bed volume
Increased capillary permeability causes extravasation of plasma and decreases blood volume
Rapid and significant drop in arterial blood pressure
cardiogenic shock
The initial stage of shock
Heart pump dysfunction leading to rapid reduction in cardiac output
Clinical manifestations: blood pressure drops significantly in the early stages of shock
Divided according to hemodynamics
Low discharge high resistance type (baroreceptor)
Low discharge and low resistance type (vessel wall volume receptor)
The development process of shock (hemorrhagic shock)
Shock stage I - the compensatory period of shock
It is the early stage of shock. During this period, the microcirculatory blood perfusion volume is reduced and tissue ischemia is severe, so it is also called the ischemia-hypoxic period.
Characteristics: less perfusion and less flow, less perfusion than flow, and the tissue is in a state of ischemia and hypoxia.
Change mechanism:
Strong excitation of the sympatho-adrenomedullary system and an increase in vasoconstrictor substances (catecholamines)
Massive blood and fluid loss, decreased blood volume, and decreased blood pressure
pain trauma causes stress
Increased catecholamines - α-adrenoceptor stimulation, contraction of skin, abdominal organs, and renal small blood vessels
Increased secretion of angiotensin 2 (Ang II), myocardial depressant factor (MDF), and endothelin (ET) - β-adrenergic receptors are excited, and the arteriovenous anastomosis branches are opened
Bacteria and endotoxin irritation
Increased vascular volume, decreased blood return to the heart, and decreased cardiac output and blood pressure
Less perfusion and less flow, less perfusion than flow, tissue ischemia and hypoxia
Arterioles, posterior arterioles, capillaries, anterior sphincter contraction, anterior resistance increases - perfusion decreases (more sensitive, more decreases)
Venule constriction, posterior resistance increases - flow decreases
Arteriovenous anastomotic branch opening
Reduced blood flow in the true capillary network - tissue ischemia and hypoxia
Compensatory significance of microcirculatory changes:
autotransfusion
Contraction of muscular venules and venules, increasing blood return to the heart
The liver, spleen and other blood storage organs shrink, reducing the capacity of the vascular bed and increasing the amount of blood returned to the heart.
The "first line of defense" to increase the amount of blood returned to the heart during shock
summary
autoinfusion
The front resistance of the capillaries is greater than the rear resistance, the hydrostatic pressure decreases, and the tissue fluid flows back into the blood vessels (the arteriole end shrinks significantly)
Increased aldosterone and antidiuretic hormone
The "second line of defense" to increase the amount of blood returned to the heart during shock
summary
Blood redistribution (guaranteeing blood supply to vital organs)
Significant contraction of skin, abdominal viscera, and kidneys
Cerebral blood vessel changes are not obvious
summary
cardiovascular dilation
increase blood volume
increased cardiac output
Increase heart pump function
Increased peripheral resistance
peripheral blood vessels
Clinical manifestations: pale face, wet limbs (sympathetic nerve excitement, increased sweat gland secretion), cold sweat, thin pulse (cardiac perfusion), blood pressure unchanged or slightly dropped or even increased, pulse pressure decreased (sign of stage I shock) Sexual signs - increased systolic blood pressure, increased diastolic blood pressure), decreased urine output, alertness, irritability
Treatment eliminates the cause, replenishes blood volume, and improves microcirculation disorders
summary
Shock stage II - the progressive stage of shock
It is also called the microcirculatory congestion phase, decompensation phase, and shock phase; during this phase, blood flow slows down significantly, red blood cells and platelets aggregate, and hypoxia becomes more severe.
Characteristics: Easy to perfuse but difficult to flow, perfusion is greater than flow, and the tissue is in a congested and hypoxic state.
Change mechanism:
Reduced responsiveness of microcirculatory vessels to vasoconstrictor regulation—reduced microcirculatory inflow resistance
Ischemia and hypoxia lead to increased CO₂, lactic acid, and decreased ATP
Decreased vascular smooth muscle tone and decreased vascular smooth muscle responsiveness to CA
The K⁺ pump opens, potassium ions flow out to form hyperpolarization, and calcium channels decrease
summary
Increase in local vasodilator metabolites - decrease in microcirculatory inflow resistance
Ischemia, hypoxia and acidosis stimulation
Mast cells release histamine
ATP breaks down to form adenosine
Cell disintegration releases potassium ions
Activation of the kinin system releases bradykinin
Endotoxins stimulate macrophages to release certain factors
Vascular smooth muscle relaxation, capillary dilation
Hemodynamic changes - increased microcirculatory outflow resistance
Leukocytes adhere to venules (flow rate decreases)
Increased blood viscosity (increased viscosity)
as a result of
The "auto-transfusion" and "auto-infusion" effects stop
Capillary blood flow stasis, increased hydrostatic pressure
Increased capillary permeability, extravasation of plasma, and hemoconcentration
A vicious cycle forms
Blood redistribution decreases, cardiac output decreases, and peripheral resistance decreases
Clinical manifestations: progressive decrease in blood pressure
The patient is apathetic or even comatose (insufficient cerebral perfusion)
Renal blood flow is severely insufficient, resulting in oliguria or even anuria
Microcirculatory congestion, cyanosis or mottling of skin and mucous membranes
Weak heartbeat, dull heart sounds, thin and rapid pulse
Shock stage III - the refractory stage of shock
Microcirculation failure stage or refractory stage, also known as irreversible stage DIC stage
Characteristics of changes: no perfusion or flow, blood hypercoagulation, no blood supply to tissue cells
mechanism
Paralytic dilation of microvasculature—loss of responsiveness to neuro-humoral regulation
Cell metabolism disorder, internal environment disorder
Vascular smooth muscle injury
Vascular smooth muscle cell membrane hyperpolarization
Increased adhesion and aggregation of blood cells
A large number of blood cells gather together, flowing slowly and swinging back and forth like "sludge"
Massive microthrombosis—DIC
Damage to vascular endothelium, exposure of tissue factor and collagen, and activation of internal and external coagulation systems
Blood cell adhesion and aggregation, blood concentration, and increased viscosity
Mononuclear phagocytes and liver cells dysfunction, and anticoagulant system decreases
Serious consequences:
The blood perfusion of tissues and organs further decreases, and local cessation
Microthrombi block, capillary no reflow
Internal environment disorder and damaging humoral factors cause systemic inflammatory response syndrome, resulting in multiple organ dysfunction or failure (MDOF or MDOS)
Clinical manifestations:
circulatory failure
refractory hypotension
Pulse is weak and rapid
Decreased central venous pressure, vein collapse
Concurrent DIC
Subcutaneous spots, spotting hemorrhages
Vital organ disorder or failure
Prevention and control principles
etiology prevention and treatment
Treat the primary disease - stop bleeding, replenish blood volume, control infection, repair wounds
Pathogenesis prevention and treatment
Improve microcirculation and increase tissue perfusion
correct acidosis
Replenish blood volume
vasoactive substances
Improve heart function
Improve cell metabolism and prevent cell damage
Use humoral factor antagonists and inhibitors
Prevent organ failure
The pathogenesis of shock
Microcirculation: Excitation of the sympatho-adrenal system and insufficient microcirculatory perfusion, causing cell damage and organ dysfunction.
Cellular mechanism: shock-causing factors act directly or indirectly on tissues and cells, causing metabolism and dysfunction of certain cells, and even structural damage.
Nerves-humoral factors: The proliferation of pro-inflammatory and anti-inflammatory humoral factors directly causes microcirculation disorders and damage to cells, tissues and organs.
Changes in the functions of various organ systems when body fluids
changes in substance metabolism
During shock, microcirculation is severely disrupted, tissue perfusion is low, and cells are hypoxic.
Cell metabolism disorders
Energy deficiency and water, electrolyte, acid-base disorders
changes in kidney function
acute renal failure
The incidence rate is second only to the lung and liver, with clinical manifestations such as oliguria or anuria, azotemia, hyperkalemia, acid metabolism, etc.
Mechanism: sharp decrease in blood volume, continuous ischemia and hypoxia, release of toxins leading to the production of inflammatory mediators
changes in lung function
changes in heart function
changes in brain function
Microcirculation
composition
(arterial end) resistance vessels: involved in regulating systemic blood pressure and blood distribution
(Venous end) Capacity vessels: involved in adjusting the amount of blood returned to the heart
(Capillary bed) exchange vessels: exchange of substances inside and outside blood vessels
adjust
Nervous and humoral regulation - vasoconstriction
Sympathetic nerve-arteriole, venule smooth muscle alpha receptor
CA, Ang₡, vasopressin, TXA₂, ET
Local metabolite regulation - vasodilation
Lactic acid, adenosine, histamine, prostacyclin (PGI2), NO, kinin, H, K, etc.
regulating characteristics
The inflow end of the microcirculation (the arteriolar end has more α-receptors) is more responsive to vasoconstrictor regulation than the outflow end.
Tolerance of microcirculatory inflow side to ischemia and hypoxia<outflow side
The skin, abdominal viscera and renal microcirculatory vessels respond strongly to vasoconstrictor regulation
shock
The definition of shock: a condition that occurs when the body is exposed to various strong damaging factors. The effective circulating blood volume throughout the body (referring to the blood volume circulating through the cardiovascular system per unit time, but does not include blood stored in the liver, spleen and lungs). The blood volume in the sinus or stagnant in the capillaries depends on - sufficient blood volume, effective cardiac output, good peripheral vascular tone), and is characterized by a sharp reduction in tissue microcirculatory blood perfusion, which in turn leads to tissue cell metabolism and The pathological process of dysfunction and dysfunction of various important life organs.
The most important thing is that the effective circulating blood volume is sharply reduced, and the blood perfusion of tissues and organs is seriously insufficient.
Cause - strong stimulation injury
Clinical symptoms - manifested as irritability, apathy or coma, pale or hairy skin, clammy limbs, reduced urine output or no urine, thready pulse, small pulse pressure or low blood pressure
Causes and classification of shock
Cause
blood and fluid loss
Severe trauma and bleeding
gastric ulcer bleeding
Esophageal variceal bleeding
Ectopic pregnancy
Postpartum hemorrhage
DIC
Severe vomiting
Sweat profusely
intestinal obstruction
severe diarrhea
Extensive burns
Early stage: plasma, fluid loss, pain
Late stage: secondary infection
hypovolemia
Trauma: pain, blood loss, tissue necrosis
Infection (most common)
Serious infections caused by bacteria, viruses, fungi, and rickettsiae
allergy
Injection of certain drugs, serum preparations, vaccines
eating certain foods
touching certain objects
Vascular origin
Heart and macrovascular disease
cardiogenic
intense nerve stimulation
Severe pain, high spinal anesthesia, overdose of central sedatives, spinal cord injury → inhibition of sympathetic vasoconstrictor function → vasodilatation of smooth muscle, increase in vascular bed volume, reduction in blood return volume, and reduction in BP
Classification
Classified by cause: hemorrhagic shock, burn shock, traumatic shock, septic shock, anaphylactic shock, cardiogenic shock, neurogenic shock
Classified according to the movement phase (blood volume decreases, vascular bed volume increases, and cardiac output decreases sharply)
Hypovolemic shock:
Shock caused by reduced body blood volume (insufficient venous return, reduced cardiac output, decreased blood pressure), mainly includes hemorrhagic and fluid loss shock, traumatic shock,
Typical clinical manifestations are "three highs and one low", with central venous pressure, cardiac output, and arterial blood pressure decreasing, and peripheral resistance increasing.
Cardiogenic shock: Heart pumping dysfunction leads to a sharp decrease in cardiac output, resulting in a significant decrease in effective circulating blood volume and microcirculatory tube flow.
Cardiac origin: myocardial infarction, cardiomyopathy, arrhythmia, valvular disease, etc.
non-cardiac origin
Decreased filling (acute cardiac tamponade, tension pneumothorax)
Obstructed ejection (pulmonary embolism, pulmonary hypertension)
summary
Vasogenic shock:
septic shock
anaphylactic shock
Appearance of endogenous vasoactive substances
neurogenic shock
Inhibition of sympathetic vasoconstrictor function
The main reasons are peripheral blood vessel dilation, blood stasis, and reduced effective circulating blood volume.