Week 2 - Shock And Stabilization Flashcards
Name conditions associated with distributive shock?
SIRS/Sepsis
Anaphylaxis/Anaphylactoid
Neurogenic
Neurogenic
Name conditions associated with obstructive shock?
Cardiac tamponade
Pleural space disease (effusion, pneumothorax, diaphragmatic hernia)
Pulmonary thromboemboli
GDV
What conditions are associated with non-circulatory shock?
Metabolic - mitochondrial dysfunction
Decreased O2 content - anaemia, Hb impairment
What is the equation for cardiac output?
Stroke volume x heart rate
What equation is this?
(SaO2 x Hb (g/l) x 1.37) + (PaO2 (mmHg) x 0.003
CaO2 - arterial oxygen content (ml/L)
What is the equation for delivery of oxygen DO2?
CO x CaO2
What is hypoxia?
Inadequate DO2 to meet the VO2 of the body
What are the 4 causes of hypoxia?
Decreased inspired O2
Inadequate tissue perfusion
Increased O2 demand
Cellular inability to DO2
What is the oxygen extraction ratio?
VO2 / DO2
What is critical O2 delivery?
O2 decreased, cells switch from aerobic to anaerobic metabolism.
What is hypoxemic hypoxia?
Decreased DO2 due to decreased CaO2 secondary to hypoxaemia from a decreased PaO2 and SaO2.
What is hypaemic hypoxia?
Decreased Hb thus reduces CaO2 thus decreasing DO2.
What is haemoglobinopathy?
Adequate Hb but Hb dysfunctional and unable to transport O2 sufficiently.
What is Stagnant/circulatory hypoxia?
Low CO and low blood load, leading to decreased DO2.
What is histotoxic hypoxia?
Adequate DO2 but tissues unable to extract and utilise O2.
Name a condition associated with histotoxic hypoxia?
Cyanide toxicity
Carbon monoxide toxicity
Mitochondrial dysfunction - Sepsis
What is metabolic hypoxia?
Adequate DO2 but increased VO2 demand (not enough to go around).
E.g. sepsis
Define shock.
VO2 exceeds DO2 and cells enter anaerobic metabolism.
What is dysoxia?
Cells unable to utilise O2 (Hisotoxic hypoxia).
What is apoptosis?
Cell death - leads to organ failure.
What is hypovolaemic shock?
Reduced volume in the intravascular space leading to decreased preload and cardiac output.
What is relative hypovolaemic shock?
Internal fluid shift from intravascular space e.g. internal haemorrhage, third spacing, massive vasodilation -sepsis.
What is absolute hypovolaemic shock?
External haemorrhage, excessive fluid loss e.g vomiting, diarrhoea, polyuria, endocrine disease.
What is distributive shock?
Systemic vasodilation
Give examples of conditions associated with distributive shock?
SIRs, SEPSIS, anaphylaxis/anaphylactoid, neurogenic shock.
What is cardiogenic shock?
Pump failure - contracting/filling leading to decreased CO and tissue hypoxia despite adequate intravascular volume.
Name conditions associated with cardiogenic shock?
Arrhythmias
Structural defect
Define obstructive shock.
Obstruction around the heart of blood vessels.
Give examples of conditions causing obstructive shock.
ATE
GDV
Pleural space disease
Cardiac tamponade
Blood back up in the right side of the heart leads to?
Cardiomegaly
Blood back up in the left side of the heart leads to?
Pulmonary oedema
Blood back up in the veins leads to?
Jugular venous distension
What is neurogenic shock?
Synthetic nervous system loses ability to stimulate nerve impulse - above T6 injury.
Give the clinical symptoms of compensatory shock
Increased: CO, BP, perfusion
Tachycardia, bounding pulses, brief CRT, pink MMC.
Give the clinical symptoms of early de-compensatory shock
Lactic acidosis
Tachycardia
Pulses weakening
Pale MMC, prolonged CRT
Tachypnoea, increased respiratory effort
Give the clinical symptoms for late decompensatory shock
Decreased CO and DO2
Bradypnoea, bradycardia, Hypotension, weak pulses, pale/cyanotic MMC, prolonged CRT, hypothermia.
In late decompensatory shock, what complications may present?
Protein loss due to increased epithelial permeability
Coagulopathies, DIC
AKD, ARDs, MODs
Dysrhythmias
Decreased mentation, coma and death
Define SIRs
Systemic inflammatory response syndrome secondary to widespread tissue isheamia and reperfusion injury.
Why does bacterial translocation occur in SIRs and what might result?
Intestinal tract is a portal for systemic inflammation and increased permeability leads to barrier dysfunction.
Sepsis may present.
Define DIC
Inflammation induced activation of the coagulation pathway leads to microthrombosis and DIC.
What is the blood volume of the cat?
60ml/kg
What is the blood volume of the dog?
90ml/kg
What are the three factors for Virchow Triad?
Vascular stasis
Hypercoagulability
Vascular trauma
What are the common places for catheter related blood stream infections to present?
Joint (hip/stifle)
Bladder
Fluid bolus recommendation dose?
5 - 20ml/kg over 10 - 20 minutes.
Hypertonic fluids cause?
A rapid fluid shift into the intravascular space causing rapid expansion of the intravascular fluid.
Synthetic colloids are out of favour as they have been associated with?
Coagulapthies
AKI
Increased mortality
Natural colloids rescusitation rates are associated with?
Transfusion reaction
TACO - Transfusion-associated circulatory overload
TRALI - Transfusion-related acute lung injury
What is a massive transfusion and how is it delivered?
Plasma, pRBC, platelets
1:1:1
lactatemia A is associated with?
Tissue hypoperfusion
Hypoxaemia
lactatemia B is associated with?
Underlying disease
Toxicity
Metabolic deficiency
Anaphylactoid are non-immunological events. What might cause this?
Heat
Cold
pharmaceutical’s
Cause degranulation of mast cells and basophils
Type 1 hypersensitivity reactions (anaphylaxis) is mediated by?
IGE
In the dog, which two systems are usually affected with anaphylactic reaction?
Gi
Integumentary
In the cat, which two systems are usually affected with anaphylactic reaction?
Respiratory
GI
With anaphylaxis, what may be seen on POCUS?
Gall bladder oedema - halo sign
What blood parameter is increased with anaphylaxis?
ALT
What drugs are given to anaphylaxis patients?
Antihistamines
Glucocorticoids
Epinephrine (first line, temporary)
Bronchodilators - Albuterol/terbutaline
What is reperfusion injury?
Cellular dysfunction and death following restoration of blood flow to previously ischemic tissues.
With reperfusion injury, free radicals in the intravascular system may cause what arrhythmia?
VPCs
Name common conditions/events associated with reperfusion injury.
GDV
ATE
CPR
Crush injury
Myocardial infarction
What are the three compartments of reperfusion injury?
Myocardial oedema
Calcium deposits
Microvascular obstruction
What percentage of blood loss will haemorrhagic shock present?
15 - 20 %
Define permissive hypotension?
Lowest acceptable BP to maintain adequate vasoconstriction until definitive haemorrhage control obtained.
What % of body water is intracellular fluid?
40%
What % of body water is extralcellular fluid?
20%
What is the % of body water of interstitial fluid?
15%
What is the % of body water of plasma?
4%
What is the % of body water of trancellular fluid?
1%
What is Isotonic fluid loss and how is it lost?
Water and solutes
Vomiting
Diarrhoea
What is hypotonic fluid loss and how does it occur?
Free water losses
Diabetes insipidus
What is hypertonic fluid loss and how does this occur?
High concentration of sodium
Addison’s disease
Third spacing
With dehydration, where is fluid lost from?
Interstitial and intracellular space
In hypovolaemia, where is fluid lost?
Intravascular space
What are the clinical symptoms of 10 - 12 % dehydration?
Severe loss of skin elasticity
Sunken eyes
Dry MM
Progressive signs of shock
What are the clinical signs of 8-10% dehydration?
Marked loss of skin elasticity
Sunken eyes
Dry MM
What are the signs of 6-8% dehydration?
Loss of skin elasticity
Slightly sunken eyes
Tacky MM
What are the signs of 5-6% dehydration?
Subtle loss of skin elasticity
What are the signs of 0-5% dehydration?
Not clinically detectable
When using crystalloids, over what time frame does 60% - 80% of the solution leave the intravascular space?
20-30 minutes
Hypotonic fluids are contraindicated with?
Hypovolaemia
Hypertonic saline may be administered to large dogs to rapidly expand the intravascular space, however what is the duration before redistribution?
Approximately 30 minutes
Must administer isotonic crystalloids alongside to treat the dehydration that the hypertonic saline produces.
What can be done to assist challenging vascular access?
Elastic wrap - peripheral oedema
Warm towel - venous distension
Tough skin - relief whole
Catheter flushing with NaCl
Ultrasound guided
When is venous cutdown for IV catheter placement indicated?
Hypovolaemia
Small veins
Obscured veins (obesity, oedema, harnatoma)
What are the three approaches for venous access?
Percutaneous - direct
Percutaneous facilitative (small skin defect)
Surgical cut down
When a CVC is to be utilised, what should be assessed prior to placement?
ACT
PT/aPTT
What are the contraindications for IO catheterisation?
Fractures
Osteomyelitis
Osteosarcoma
Name the peripheral sites for arterial catheterisation?
Dorsal pedal artery
Radial artery
Auricular artery
Femoral artery
Brachial artery
IO catheters can be placed in which sites?
Humeral head
Flat medial surface of the proximal tibia
The trochanter is fossa of the femur
Name the complications of IO catheter placement
Extravasation
Fracture
Osteomyelitis
cellulitis
Fat embolism
IO catheters are contraindicated in what species and which bone?
Pneumatic bones in avians
When using the saphenous vein for CVC, where is the catheter advanced to?
Caudal vena cava
When using the jugular vein for CVC, where is the catheter inserted to?
Superior vena cava
Name 5 sites for arterial catheterisation.
Dorsal pedal artery
Femoral artery
Auricular artery
Radial artery
Coccygeal artery
Name the Resuscitation endpoints.
Improved HRT/Pulses/CRT
Improved mentation
Normotension
Blood work - lactate normalisation
Isotonic crystalloids for shock resuscitation are administered at…
10/20 ml/kg/15-30 minutes
Synthetic colloids for shock resuscitation are administered at…
1-5ml/kg over 10/30 minutes
Hypertonic solutions for shock resuscitation are administered at…
3-5ml/kg over 20-30 minutes of 7%~7.5% NaCl
pRBCs and FFP for shock resuscitation are administered at…
10-20ml/kg over 2-4 hours
Fresh whole blood for shock resuscitation are administered at…
20-30ml/kg over 2-4 hours
Albumin is typically reserved for patients with what conditions?
Hypoalbuminemia - secondary to sepsis, septic shock, trauma.
When fresh while blood is not available, what ratio is FFP and pRBCs administered?
1:1
In rapidly decompensating patients, blood transfusions may be administered faster at what rate?
1.5ml/kg/min over 15-20 minutes
Severe anaphylaxis may lead to?
Multi-organ deregulation
DIC
What is a biphasic anaphylaxis?
Relapse
Name the suggested treatment for anaphylaxis.
O2 therapy - resp compromise
IV access
IVFT - Hypovolaemia
Epinephrine - vasoconstriction, reduce mucosal oedema
Diphenhydramine - antihistamine
Dexamethasone
Albuterol, terbutaline - bronchodilation
Name the six physical examination parameters to assess perfusion.
HRT
pulse quality,
MBC
CRT
Peripheral temperature
Mentation
Haemorrhagic shock can result in lethal triad, what three conditions are associated with this?
Coagulopathy
Acidosis
Hypothermia
With massive transfusion, what may happen to the ionised calcium and magnesium?
Ionised hypocalceamia
Hypomagnesemia
Which type of shock has a decreased circulating blood volume?
Hypovolaemic
What type of shock has a marked decrease or increase in systemic vascular resistance or maldistribution of blood?
Distributive
What type of shock has a decrease in forward flow from the heart?
Cardiogenic
What toe of shock has reduced diastolic filling and preload?
Obstructive
In sepsis, what indicates septic shock?
Persistent hypotension requiring vasopressors
What causes primary hypothermia?
Excessive exposure to low environmental temperatures.
What causes secondary hypothermia?
Disease, trauma, surgery, drug induced alteration in thermoregulation.
