6.Shock Flashcards
anaphylactic shock is classified by what type of shock?
a. Hypovolemic
b. Cardiogenic
c. Distributive
d. Hypoxic
c. Distributive - correct
Septic shock is classified by what type of shock?
a. Hypovolemic
b. Cardiogenic
c. Distributive
d. Hypoxic
c. Distributive - correct
CO x arterial oxygen content =?
Global oxygen delivery (DO2) which reflects the total vol of oxygen delivered to the tissues per minute, irrespective of how blood flow is distributed in the regional circulation.
1) What is true regarding defects in oxygen uptake?
a) Diffusional resistance is caused by slow blood velocity
b) Diffusional shunting results from poor diffusion of oxygen to reach the cells
c) Perfusion/metabolism mismatch occurs during a PTE
d) Cytopathic hypoxia is classically associated with sepsis
D is correct = mitochondrial dysfunction
slow blood –> diffusional shunting
Edema and increased distance –> more diffusional resistance
PTE/thrombi–>arteriovenous shunting
sustained tachycardia –>perfusion mismatch (not enough coronary perfusion and increased O2 demand)
How much oxygen is carried by 1 gram of fully saturated hemoglobin? a)0.34 b)0.15 c)1.34 d)0.003
c) 1.34
What is the oxygen solubility coefficient at 37 degrees Celsius? a)0.003 b)0.05 c)0.15 d)0.08
a)0.003
What causes a left shift in the oxygen-hemoglobin dissociation curve? a)Decreased temperature b)Decreased pH c)Increased DPG d)Increased PaCO2
a)Decreased temperature
Which of the following is not a mechanism of providing adequate oxygen delivery in
shock?
a.Maintaining mean circulatory pressure
b.Maximizing cardiac performance
c.Redistributing perfusion
d.Optimizing oxygen perfusion at the lungs
D optimizing oxygen unloading
Do
circulating volume and pressure
max cardiac performance
Which of the following is true?
a.Baroreceptors in the thoracic arteries (carotid sinus and aortic arch) stimulate
parasympathetic reflexes
b.Chemoreceptors within the carotid and aortic bodies are activated in response
mainly to increase in H+ or CO2
c.Chemoreceptors aide in activation of respiration leading to enhanced
oxygenation and CO2 elimination
d.Reduced circulating volume leads to stimulation of baroreceptors which leads to
constriction of arterioles and relaxation of venules and veins
C is correct
Sympathetic reflexes stimulated by baroreceptors
Chemoreceptors sense reduction in o2 and lesser extent them; H+ and CO2 more sensitive in brain stem)
activated baroreceptors–> constriction of
both arterioles and veins
Which is true?
a.The absence of a palpable pulse in a peripheral artery is considered a sign of
hypotension with a systolic arterial pressure less than 60 mm Hg.
b.Loss of a palpable femoral pulse is considered a sign of profound hypotension
with a systolic arterial pressure less than 40 mm Hg.
c.There is no clinical data to support determining BP from pulse palpation.
d.In dogs, the shock organ is the lungs, whereas in cats the shock organ is the GI
tract.
C is correct
(80 mm Hg) peripheral
(60 mm Hg) femoral
cats = lung, dogs = GI
MAP ranges that keep the following organs at a constant perfusion?
a. Renal circulation →
b. Myocardial circulation →
c. Cerebral circulation →
a. Renal circulation → 70 to 130 mm Hg
b. Myocardial circulation → 60 to 140 mm Hg
c. Cerebral circulation → 50 to 180 mm Hg
What is the equation to estimate mean arterial pressure?
a.MAP = DAP +1/3 × (SAP −DAP)
Which is false?
a.To limit possible errors, the BP cuff width should be 40% of the limb circumference
b.Central venous pressure (CVP) is the hydrostatic pressure measured through a
catheter, in which the tip is placed in the cranial or caudal vena cava or in the
right atrium
c. Physiologic CVP for the dog and cat is between 0 and 5 cm H2O
d.The gold standard for cardiac output measurement involves thermodilution
and requires the placement of a Carl-tanner pulmonary artery catheter.
D
d.The gold standard for cardiac output measurement involves thermodilution
and requires the placement of a – pulmonary artery catheter.
(Swan-Ganz art cath)
When should oxygen therapy be continued after initial stabilization of a patient in shock?
a. SpO2 < 94% or PaO2 < 80 mm Hg
b. SpO2< 80% or PaO2 < 60 mm Hg
c. When PaO2:FiO2 ratio > 500
d. When gums are still cyanotic indicating >3 to 5 g/dL of deoxygenated hemoglobin
A is correct
(Normal PaO2 > 90 mm Hg)
(Normal PaO2/FiO2 ratio should be approximately 500)
d.When gums are still cyanotic indicating >3 to 5 g/dL of deoxygenated hemoglobin in circ (This is subjective but true, so not the best answer when thinking about goal directed endpoints)
At what point does oxygen toxicity occur?
a. Exposure to 40% Fi O2 for 48 hours
b. Exposure to 60% FiO2 for > 24 hours
c. O2 flow > 100 ml/kg/min in a nasal canula
d. 2-3 L/min of flow by
B is correct
c.O2 flow > 100 ml/kg/min in a nasal canula (reported to cause patient discomfort)
d.2-3 L/min of flow by (this is a normal supportive care to provide about 25-40%
FiO2)
What is a documented reason to avoid colloids in critical canine patients?
a.Renal lesions and renal dysfunction after administration
b.Coagulopathy from reduction in circulating fVIII and vWB factor, nonspecific
platelet coating, and interference with fibrin polymerization
c.All of the above
C. Both
a.Renal (conflicting evidence,
AKI known in people)
b.Coagulopathy(unknown clinical
significance in veterinary patients)
What is NOT a benefits of hypertonic saline?
a. Reduction of endothelial swelling
b. Increased intracranial pressure
c. Immunomodulation
d. Improved myocardial function
B
(Decreased) intracranial pressure
T/F: Glucocorticoids should be considered in septic patients?
TRUE at LOW doses– when vasopressor-refractory hypotension is noted.
