Shock

Shock, Sepsis, and MODS

• Complex disorders • Affect body in multifaceted dimensions• Involve breakdown in oxygen supply and demand• Begin with localized tissue damage, may progress to

organ failure and death

Cellular Respiration (1 of 3)

• Produces ATP• Involves three parts

– Glycolysis (occurs in both aerobic and anaerobic environments)

– Citric acid cycle (aerobic environment)– Electron transport chain (aerobic environment)

Cellular Respiration (2 of 3)

Cellular Respiration (3 of 3)

Aerobic Metabolism

• Mitochondria utilize glucose, amino acids, and fatty acids combined with oxygen and ADP to produce:– ATP– Carbon dioxide– Water– Heat

Anaerobic Metabolism

• Alternative pathway converts glucose to pyruvic acid and produces ATP

• Less ATP results

Microcirculation and the Cell (1 of 3)

• Understanding the imbalance between oxygen supply and demand is critical.

• Microcirculation– Nexus between arterioles and venules consisting of the

capillaries– “Crash site” hidden deep at cellular level

Microcirculation and the Cell (2 of 3)

• Oxygen transport and utilization– Homeostatis requires supply of oxygen sufficient to meet

the body’s cellular demands– Cardiovascular system delivers oxygen-rich blood to the

tissues– When the oxygen-bound hemoglobin reaches the

capillaries, oxygen is released from the hemoglobin to the cells in exchange for cellular waste.

Microcirculation and the Cell (3 of 3)

Four Stages of Shock (1 of 5)

• Initial stage– Blood flow to microcirculatory beds decreases.– Hypoxia develops.– Cells cannot maintain homeostasis.

• Compensatory stage– Body uses physiologic mechanisms to maintain cellular

homeostasis

Four Stages of Shock (2 of 5)

Four Stages of Shock (3 of 5)

Four Stages of Shock (4 of 5)

Four Stages of Shock (5 of 5)

• Progressive (decompensatory) stage– Occurs when underlying cause untreated– Life-threatening emergency– Requires early fluid resuscitation and vasopressor

support

• Refractory or irreversible stage– Failure of compensatory mechanisms – Tissues and organs die– Highest mortality rate

Effects of Shock on the Body

Two Types of MODS

• Primary– Results from direct insult (trauma)

• Secondary– More progressive insult to organs– More common– Earliest affected organs: brain, kidneys, liver, adrenal

glands, heart

Organs Affected by Hypoperfusion

Classification of Shock (1 of 6)

• Cardiogenic shock– Failure of heart to pump blood effectively– Numerous intrinsic causes; left ventricular failure due to

MI most common– Numerous extrinsic causes (examples: pericardial

tamponade, pneumothorax)– Manifestations vary depending on underlying cause

Classification of Shock (2 of 6)

Classification of Shock (3 of 6)

• Hypovolemic shock– Low circulating blood volume results in hypotension

with blood or fluid lost or displaced internally or externally.

– Various associated conditions (examples: fever, vomiting, diarrhea, burns)

– Signs and symptoms include tachycardia, hypotension, confusion

Classification of Shock (4 of 6)

Classification of Shock (5 of 6)

• Distributive shock includes:– Neurogenic shock: Loss of sympathetic tone caused by

trauma, drugs– Anaphylactic shock: Life-threatening allergic reaction

caused by numerous antigens; includes true anaphylaxis and anaphylactoid reaction

– SIRS, sepsis, and septic shock: Progressive disease caused by infection

Classification of Shock (6 of 6)

SIRS

Sepsis Definitions (1 of 2)

• Sepsis – Mild systemic response to (bacterial) infection or

suspected infection

• Severe sepsis – Sepsis with diagnosis of infection and dysfunction of

one organ minimum

• Septic shock– Hemodynamic instability with SIRS

Sepsis Definitions (2 of 2)

Sepsis Epidemiology (1 of 2)

• Prevalence increasing– 1.1 million new cases by 2020 anticipated by CDC

• All populations and age groups affected• Mortality rates for severe sepsis

– Leading cause of death in non-coronary ICUs– 10th leading cause of death in United States

Sepsis Epidemiology (2 of 2)

Sepsis Pathophysiology (1 of 5)

• Pathogens (usually bacteria)– Identified as non-self– Activate immune system response

• Infection– Invasion of host by pathogen(s)– Innate immune system stimulates inflammatory process

Sepsis Pathophysiology (2 of 5)

Sepsis Pathophysiology (3 of 5)

• Systemic infection– Activates widespread inflammatory response throughout

body, overwhelming immune system– Involves: proinflammation, procoagulation, decreased

fibrinolysis

Sepsis Pathophysiology (4 of 5)

Sepsis Pathophysiology (5 of 5)

Sepsis Assessment

• Maintain high index of suspicion by considering:– Thorough patient history correlated with patient

presentation– Infection not necessarily required– Fever may not present in all populations

• Review signs and symptoms– Distributive shock, infection, cardiovascular changes,

tachycardia

Sepsis Management (1 of 2)

• Early recognition and management are vital• Fluid resuscitation

– Volume expansion to optimize CO

• Vasopressor and inotropic support:– Dobutamine, phenylephrine, epinephrine, vasopressin

• Infection control• Immune-specific therapy

Sepsis Management (2 of 2)

Reproduced from Rivers, E., Nguyen, B., Havstad, S., et al. Early goal directed therapy in the treatment of severe sepsis and septic shock. N Engl Med 2001; 234(19):1371. Copyright © 2001 Massachusetts Medical Society. All rights reserved.

Blood Administration Considerations

• Results of risk-benefit analysis to weigh: – Urgency, “out-of-hospital” time, availability, type-and-

crossmatch information

• Possible complications• State regulations• Care, storage, transport of blood products• Skill of health care provider

ABO System

• Identifies antigens A and B to determine following blood types:– Type A, type B, type AB, type O

• Identifies universal recipients– People who are type AB

• Identifies universal donors– People who are type O; can only receive this type

themselves

Blood Administration Complications

• ABO-incompatible transfusion reactions– Patient receives blood type for which they have antibodies

• Rh-negative exposure to Rh-positive blood– Patient may have fatal hemolytic reaction on second

exposure

• Human leukocyte antigen (HLA)– Patients receiving blood from multiple donors may develop

fever

Blood Products

• Blood components and derivatives include:– Whole blood: Contains all blood components, degrades

quickly– Packed red blood cells (PRBCs): Retain characteristics of

whole blood except 250 mL of platelet-rich plasma

Platelet Products (1 of 2)

• Fresh-frozen plasma (FFP)– Uncoagulated plasma separated from RBCs; used for blood

loss, coagulation deficiencies, warfarin reversal, thrombotic thrombocytopenic purpura

• Cryoprecipitate– Frozen blood product created from donor’s plasma; used

for hemophilia A, fibrinogen deficiency, von Willebrand’s disease

Platelet Products (2 of 2)

• Albumin– Fractionation of pooled plasma

• Plasma protein fraction– Contains 83% albumin, 17% globulins

• Synthetic blood substitutes– Research and development ongoing– PolyHeme

Indications for Blood Administration

• Significant hypovolemia as the result of acute blood loss• Symptomatic anemia• Decreasing hemoglobin level• Decreasing hematocrit value • To increase oxygen-carrying ability• Decreased clotting factors• Presurgical care in select cases

Skill Drill 9-1: Administering Blood Products (1 of 3)

Confirm the order or protocol.

Check the patient for the following: right patient, right blood product, and right type. Have a second provider confirm steps 1 and 2 with you.

Assess baseline vital signs and temperature.

Skill Drill 9-1: Administering Blood Products (2 of 3)

Ensure suitable venous access. Check the blood again. Assess the patient for the possibility of a transfusion reaction, and consider prophylactic administration of medications. Maintain the temperature of the blood product.

Flush the tubing with normal saline. Cover the administration filter with blood.

Connect the blood to the tubing.

Skill Drill 9-1: Administering Blood Products (3 of 3)

Piggyback into the IV line of normal saline.

Start the transfusion slowly. Monitor for adverse reactions.

Transfusion Reactions (1 of 3)

• Allergic reaction– Caused by allergens in donated blood– Treatment: Antihistamines, patient monitoring

• Bacterial contamination– Occurs during phlebotomy, component preparation, blood

thawing– Treatment: Stop transfusion, begin protocol for transfusion

reactions

Transfusion Reactions (2 of 3)

• Febrile transfusion reactions– Bacterial lipopolysaccharides or antileukocyte recipient

antibodies – Treatment: Antipyretics, antihistamines

• Hemolytic transfusion reactions– Immediate or delayed– Various causes related to incompatibility or error

Transfusion Reactions (3 of 3)

• Plasma protein incompatibility– Immunoglobulin A incompatibility

• Other causes– Bleeding tendencies– Circulatory overload– Hypocalcemia– Hypothermia– Potassium intoxication