Flashcards in Shock Deck (158):
Is loss of total body water dealing with dehydration or hypovolemia?
Is a decrease in circulating vascular volume associated with dehydration or hypovolemia?
Which is manifested by decreased skin turgor, tacky or dry mucous membranes and sunken eyes, dehydration or hypovolemia?
Which is manifested by tachycardia (or bradycardia in cats), prolonged CRT, poor peripheral pulses and decreased urine output, dehydration or hypovolemia?
Inadequate water in take and excessive fluid losses can be causes of what?
Blood loss, severe dehydration or redistributions of fluids within the body can result in what?
You see intravascular compromise with what type of shock?
What are 2 examples of circulatory functions that the body is unable to perform with circulatory shock?
- Supply cells with oxygen
- Remove waste products
Cardiogenic shock is due to failure of what part of the CV system?
Failure of the pump.
Distributive shock is due to failure of what part of the CV system?
Failure of the tubing.
Hypovolemic shock is due to failure of what part of the CV system?
Failure of the fluid.
T/F: Certain kinds of shock are life threatening if not recognized early and treated.
False - Any kind of shock is life threatening.
T/F: Shock is a very simple process.
False - It is a very complicated process.
What are 5 classifications of circulatory shock?
- Vasodilatory or distributive
- Combination of above
What are 3 types of hypovolemic shock?
- Redistribution of fluid (edema)
What is the most common type of circulatory shock?
Which classification of shock is due to failure of the pump?
Which classification of circulatory shock is due to failure of the tubing or inflammatory substances in the tubing?
Vasodilatory or distributive
Which classification of circulatory shock is most commonly associated with sepsis?
Vasodilatory or distributive
Conditions such as GVD, pericardial effusion, venous thrombosis and tension pneumothorax can lead to what type of circulatory shock?
Obstructive shock can lead to what other type of shock if flow to the heart is obstructed?
What is a cause of hemorrhagic hypovolemic shock?
Blood loss often related to trauma.
What are 5 causes of non-hemorrhagic hypovolemic shock?
What are 3 examples of places fluid may be redistributed to with redistributive hypovolemic shock?
- Body cavities
- Peripheral tissues (edema)
An internal or external loss of greater than 15% of the body's blood volume can lead the what type of shock?
Hemorrhagic hypovolemic shock
Loss of a large fluid volume to the external environment can lead to what type of shock?
Non-hemorrhagic hypovolemic shock
Intravascular fluid depletion (fluid shifts) can lead to what type of shock?
Redistributive hypovolemic shock
What type of hypovolemic shock can be seen with low plasma protein levels?
What are 3 examples of conditions that can lead to cardiogenic shock?
- Severe acquired heart disease
- Severe congenital heart disease
- Anesthetic overdose
What are 4 examples of severe acquired heart disease that can lead to cardiogenic shock?
- Myocardial trauma
- Pericardial tamponade
What is more common, venous obstruction or arterial obstruction?
What is an example of an arterial obstruction?
What is the treatment for obstructive shock?
Relieve obstruction and use IV fluids.
What type of shock is caused by circulation of inflammatory mediators associated with SIRS?
Vasodilatory or distributive shock
What is the pathogenesis of vasodilatory/distributive shock?
- Hypoperfusion despite increased blood volume and increased cardiac output
- Maldistribution of blood from central circulation
What are 6 possible causes of vasodilatory/distributive shock?
Which is the most common?
- Sepsis (most common)
- Massive muscle trauma
Systemic infection is known as what?
Sepsis plus dysfunction of one or more organs is known as what?
What are 8 examples of possible cause of severe sepsis?
- Endothelial (vasculitis)
- Laminitis (horses)
When the body reacts via immune and inflammatory responses when the cell wall of Gram negative bacteria is destroyed resulting in decreased perfusion and severely altered hemodynamics non-responsive to fluid resuscitation, the condition is known as what?
What are 7 examples of gram negative bacteria that are normal inhabitants of our GI tract?
- E. coli
Can gram positive bacteria cause sepsis?
What are the 2 phases seen with sepsis, endotoxemia and septic shock?
- Hyperdynamic (warm)
- Hypodynamic (cold)
Is high cardiac output seen with the hyperdynamic or hypodynamic phase of septic shock?
Is low peripheral resistance because of vasodilation from "chemical" seen with the hyperdynamic or hypodynamic phase of septic shock?
Is Low cardiac output seen with the hyperdynamic or hypodynamic phase of septic shock?
Increased peripheral resistance is seen with which phase of septic shock, hyperdynamic or hypodynamic?
Is decreased blood pressure seen with the hyperdynamic or hypodynamic phase of septic shock?
Are decreased heart rate, CVP and a weak pulse seen with the hyperdynamic or hypodynamic phase of septic shock?
Capillaries are more permeable leading to leakage, fluid shifts and third spacing with which phase of septic shock?
Are cool extremities and a low temperature seen with the hyperdynamic or hypodynamic phase of septic shock?
Are pale to cyanotic mucus membranes and prolonged capillary refill time seen with the hyperdynamic or hypodynamic phase of septic shock?
Which phase of septic shock is rarely seen in cats?
You see an increased heart rate, respiration rate and temperature with which phase of septic shock?
Which phase of septic shock can progress to become multiple organ dysfunction syndrome (MODS)?
Which phase of septic shock is more common in cats?
Is rapid capillary refill time and red mucous membranes seen with the hyperdynamic or hypodynamic phase of septic shock?
The pathophysiology of shock starts with what?
The blood volume of dogs and most large animals is what percentage of their body weight?
8-9% (80-90 mL/kg)
- Use 9%
The blood volume for cats is what percentage of their body weight?
5-6% (50-60 mL/kg)
- For our purposes use half of the dog value, so about 45 mL/kg
Blood volume is composed half and half of what 2 things?
If one bag of whole blood is 450 mL, how many bags of whole blood does a 10 kg dog have?
During the compensated stage, blood volume decreases leading to a decrease in vessel filling and activation of stretch and baroreceptors, resulting in an increase in sympathetic stimulation and vasoconstriction. Why does this happen?
To try to maintain blood pressure.
During the compensated stage of shock, what happens to cardiac contractility and heart rate?
They both increase.
During the compensated stage of shock, what happens to blood flow to non-vital organs?
What are these organs called?
- It decreases.
- Shock organs
What are the shock organs of the dog, horse, cats, ruminants and pigs?
- Dog: GI and liver
- Horse: GI and lungs
- Cat, Ruminants, Pig: lungs
What can the compensated stage progress to?
The de-compensated stage.
Over time, if the blood volume problem is not fixed, the local tissue beds that were vasoconstricted will begin the vasodilate, leading to pooling of blood and maldistribution of blood flow to "non-essential" organs during what stage of shock?
There is decreased venous return to the heart during what stage of shock?
During the decompensated stage of shock, the loss of integrity of capillary membranes leads to what?
T/F: During the decompensated stage of shock, there is and increase in myocardial contractions, cardiac output and blood pressure.
False - There is a decrease in myocardial contractions, cardiac output and blood pressure.
During the decompensated stage of shock, poor perfusion leads to what?
The release of chemicals that impede cellular metabolism.
During the decompensated stage of shock, stagnant blood flow can lead to the aggregation of WBCs, RBCs and platelets, which can then lead to what?
Thrombi formation and the release of more chemicals that destroy cells.
What syndrome may be associated with the decompensated stage of shock?
MODS: multiple organ dysfunction syndrome
What are the 5 signs of hypovolemic shock?
- Tachycardia in dog, but often bradycardia in cat
- Pale mucous membranes
- Prolonged CRT
- Cool limbs
- Weak pulse (MAP 70 mm Hg)
Signs of what type of shock can overlap with hypovolemia?
What are 3 signs of heart failure to look for with cardiogenic shock?
- Loud murmur
- History of heart disease
What are 4 signs of low cardiac output that could be associated with cardiogenic shock?
- Pale mucous membranes
- Prolonged CRT
- Cool limbs
How do you treat hypovolemic non-hemorrhagic shock?
Rapid fluid replacement if no head or lung injury.
How do you administer fluids for hypovolemic non-hemorrhagic shock?
What gauge needles for cats and dogs?
- IV catheter
- 18-20 g for cat/ 14-18 g for dogs
If no peripheral access for the IV catheter, what are 3 intraosseus sites that can be used?
- Humeral shaft
- Tibial crest
What fluid type is used for hypovolemic shock?
What are 3 examples of these?
- Crystalloid replacement
- Normosol R, PlasmaLyte A, LRS
What is an example of a crystalloid replacement that is more acidic but is a good choice for patients with projectile vomiting or metabolic alkalosis?
What is the fluid administration rate for hypovolemic shock?
- Same as one circulating blood volume; same as amount of blood you would normally have circulating.
- Dogs: 90 mL/kg/hr
- Cats: 45 mL/kg/hr
How much of the calculated shock dose needs to be given ASAP (over 15 minutes of less)?
What 4 aspects of perfusion needs to be reassessed after administration of fluid has begun?
- 1/4 of calculated dose
- Heart rate, blood pressure CRT, urine output
What are 2 ways to adjust the fluid rate when treating hypovolemic shock?
Which was is less likely to lead to volume overload?
- Administering rest of dose IV over next hour.
- Administering 1/4 shock dose bolus q 15 minutes followed by re-assessment. (Less likely to lead to volume overload).
Should a shock dose be given if dog is anemic?
Yes, if dog is in shock, but if dog is obviously anemic, then hemorrhagic hypovolemic shock is present and a blood transfusion will be necessary.
While working on getting a blood transfusion for a dog with hemorrhagic hypovolemic shock, what can be given?
Start crystalloid for shock (1/4 calculated dose) but add in colloid (Hetastarch or dextran) to help restore oncotic pressure and prevent interstitial edema.
Do you give a shock dose if a dog has low albumin?
What does the low albumin cause?
What can be added to help with this?
- Yes, if dog is in shock.
- If dog has low albumin, the amount of crystalloid needed to restore intravascular volume will result in dilution of oncotic proteins which can cause "third spacing".
- Add in colloid (hetastarch or dextran) to help restore oncotic pressure and prevent interstitial edema.
What is the goal when trying to give fluids to a dog in shock with low albumin levels?
To keep fluid in the intravascular space and out of the interstitial space.
What solution used with head trauma or lung injuries helps to draw fluid from interstitial space into intravascular space?
Using hypertonic saline in head trauma or lung injuries results in what?
Rapid, but transient, increase in circulating volume.
What allows hypertonic saline to stay in intravascular space longer?
Concurrent colloid use.
Use of hypertonic saline in the fluid treatment of head trauma or lung injuries should be followed with what?
With crystalloids at maintenance rate.
What are 2 contraindications of hypertonic saline use?
- Heart failure
What are 2 types of transfusions used in the treatment of hypovolemic hemorrhagic shock?
- Whole blood
- Packed RBCs
What is the universal donor dog blood type?
DEA 1.1 neg
Is blood typing or cross matching recommended for a cat?
What is an alternative to blood products in the treatment of hypovolemic hemorrhagic shock?
Transfusion of Oxyglobin
What is the hemoglobin based, oxygen carrying solution that can be used in the treatment of hypovolemic hemorrhagic shock?
How does Oxyglobin work?
Binds to pulmonary O2 and carries it to tissues and cells.
T/F: Oxyglobin is of small molecular size so it is able to pass through microcirculation.
Is Oxyglobin currently available in the US?
What are 2 indications for the use of Oxyglobin?
- Severe anemia
- Hypovolemic shock caused by blood loss or maldistribution of blood flow.
T/F: Oxyglobin has a vasoconstricting effect that increases the volume needed for resuscitation.
False - It decreases the volume needed.
Treatment for septic shock involves fluid therapy similar to what other kind of shock?
What else is used in the treatment of septic shock?
Broad-spectrum antibiotics based on suspected pathogen.
If there is peritonitis involved with septic shock, what is done?
Surgical exploration and drainage
What is used to improve the efficacy of antithrombin III in neutralizing activated coagulation factors?
What are 4 ways oxygen can be delivered if needed in the treatment of septic shock?
- Nasal catheter
- Face mask
The use of vasopressors in the treatment of septic shock is considered with what 3 conditions?
All these parameters tell us what about continued administration of IV fluids or blood/blood products?
- Jugular vein distended
- Crackles are heard on auscultation
- CVP > 10 cm H2O
- Continued administration is contraindicated (due to fluid overload).
T/F: Prognosis in septic shock cases is very guarded.
T/F: Intensive care is not necessary with septic shock.
False - Intensive care is needed.
What are 2 examples of vasopressors?
What is another name for a pericardial tamponade?
What are 4 possible forms of treatment for cardiogenic shock?
- Pericardial tamponade pericardiocentesis)
- Positive inotropes
What type of fluid therapy should be used in the treatment of cardiogenic shock?
Minimal fluid therapy until cardia function can be accurately determined.
What can be used to treat congestive heart failure?
What are 8 things to monitor in patients with any type of shock?
- Heart rate
- Pulse quality
- Respiration rate and effort
- Urine output
- Blood pressure
What is a good way to determine if renal perfusion is adequate or not?
What is a normal volume of output?
- Urine output
- 1 mL/kg/hr (interpret amounts based on volume of fluids administered)
What is considered a strong pulse clinically?
MAP > 80 mm Hg
A CVP greater than what value indicates fluid overload is occurring?
CVP > 12-15 cm H2O = fluid overload
What does SIRS stand for?
Systemic Inflammatory Response Syndrome
An imbalance of pre-inflammatory (excess) and anti-inflammatory mediators (not enough) on a systemic scale in response to an insult is known as what?
Systemic Inflammatory Response Syndrome (SIRS)
What are 3 examples of pro-inflammatory cytokines?
What are 3 examples of anti-inflammatory cytokines?
What are 6 examples of other molecules that up-regulate inflammation?
- Nitric acid
- Platelet activating factor
- Free radicals
Inflammation is a normal response to infectious and non-infectious insults, characterized by what 5 signs?
- Loss of function
T/F: Usually inflammation is contained.
What results when inflammation is not contained?
Systemic Inflammatory Response Syndrome (SIRS)
What part of the body is affected with SIRS?
The whole body.
What does PAMPs stand for?
Pathogen-associated molecular patterns
What does PRRs stand for?
Pattern recognition receptors
Are PAMPs expressed by the pathogen/insult or the host?
Are PRRs expressed by the pathogen/insult of the host?
What are 2 examples of PAMPs?
- Lipopolysaccharide (LPS or endotoxin) of gram negative bacteria
- Peptidoglycan of gram positive bacteria in case of sepsis
What are 3 examples of cell types that PRRs can be found on?
What does the stimulation of PRRs result in?
Intracellular signaling cascade that releases pro-inflammatory cytokines.
When SIRS is due to infection, it is called what?
What are 6 non-infectious causes of SIRS?
- Trauma and hemorrhage
- Hypoxia and ischemia
Why are infectious and non-infectious SIRS often indistinguishable clinically?
Pathophysiology is same with exception of the initiating insult.
What are the 3 aspects of the second hit theory?
- Initial event primes the immune system.
- Second event occurs.
- Second event can result in excessive inflammatory response because the immune system has been primed.
A clinical diagnosis of SIRS is made based on what 2 things?
- WBC count
T/F: There is no consensus in veterinary medicine as to what denotes SIRS in the various species.
SIRS may be suspected if 2 or more of what 4 criteria exist?
- Abnormal temperature: fever usually but hypothermia more common in cats.
- Abnormal heart rate: usually tachycardia but bradycardia more common in cats.
- Tachypnea: due to increased metabolic stress or inadequate perfusion.
- Change in WBC count: Leukocytosis, leukopenia, significant left shift.
What does MODS stand for?
Multiple Organ Dysfunction Syndrome
Altered function of 1 or more organs in an acutely ill patient such that homeostasis cannot be maintained without intervention is known as what?
Multiple Organ Dysfunction Syndrome (MODS)
What is the mortality rate of multiple organ dysfunction syndrome (MODS)?
Multiple Organ Dysfunction Syndrome (MODS) can be a progression of what 2 conditions?
- Septic shock
What are 4 examples of conditions that can lead to hypovolemic, vasodilatory or cardiogenic shock and death that can be seen with MODS?
- Respiratory failure
- Hepatic failure
- Gastrointestinal bleeding
- Renal failure
What does DIC stand for?
Disseminated Intravascular Coagulation
Failure of the coagulation system resulting in widespread clotting at the same times of bleeding is known as what?
Disseminated Intravascular Coagulation (DIC)
A malfunction of what 2 pathways is seen with Disseminated Intravascular Coagulation (DIC)?
- Coagulation pathway
- Fibrinolytic pathway
What is the main trigger for DIC in nearly all disease states?
The pathologic exposure, expression or release of tissue factor.
What initiates coagulation through the extrinsic pathway of coagulation, which is then amplified by excessive thrombin generation?
At the same time, what is released from endothelial cells and initiates systemic fibrinolysis?
- Tissue factor
- Tissue plasminogen activator
What can lead to thrombus formation which decreases blood flow?
Hypocoagulation results in what?