Triage and Shock

Question 1

What is triage (2)

Answer 1

Processofquicklyexaminingpatientswho are taken to todecidewhichonesare the mostseriouslyilland must betreatedfirst
Processofexaminingproblemsinordertodecidewhichonesare the mostseriousand must bedealtwith first

Question 2

What is shock

Answer 2

Inadequate cellular energy
Most commonly secondary to poor tissue perfusion (low or unevenly distributed blood flow)
Leads to critical decrease in oxygen delivery (DO2) compared to oxygen consumption in the tissues (VO2)

Question 3

Signs of shock (4)

Answer 3

Altered mentation
Mucous membranes- pale to white or red
Capillary refill time >2 seconds (could also be shorter in SIRS & sepsis)
Cold extremities
Weak pulse

Question 4

Why does mentation change in sock

Answer 4

Brain is an obligate user of oxygen and glucose and has few energy stores
Inadequate delivery of oxygen and glucose to the brain results in loss of the normal mental state

Question 5

Descriptions used to describe mentation (4)

Answer 5

Alert and normally responsive
depressed or obtunded
stuporous or semi comatose (suggests functional brain disease)
Comatose (suggests functional brain disease)

Question 6

Normal colour of mucous membrane (and how different in cats/horses)

Answer 6

Salmon pink
Cats/horses- normally paler

Question 7

What does red mucous membranes suggest

Answer 7

Poor perfusion and vasodilation (blood trapped within the capillary beds) as in sepsis (or SIRS)

Question 8

How is CRT different in different locations

Answer 8

buccal (lips/cheek) mucosa refills slower than gingival (gums) mucosa

Question 9

What determines CRT

Answer 9

Pre-capillary Sphincter tone
increase in tone-> lengthening CRT (and vice versa)

Question 10

What does pulse evaluation tell us

Answer 10

Estimation of stroke volume
Pulse gives us the difference between diastolic and systolic pressure- no info about blood pressure
Weak pulse= hypovolaemia

Question 11

What is a hyperdynamic or bounding pulse and when does it occur

Answer 11

In early, compensated hypovolaemia
Pulse profile that is taller and narrower than normal reflecting decreased pulse volume, the heart is having to work harder
can also be due to increase CO as a result of increased oxygen demand e.g. after exercise

Question 12

What happens as severe hypovolaemia progresses

Answer 12

Becomes decompensated hypovolaemic shock
Global tissue perfusion severely compromised
Increased heart rate (170-220bpm in dogs)
Femoral pulse is short and narrow- weak or thready and metatarsal pulses are absent- metatarsal lost first

Question 13

What is SIRS

Answer 13

Systemic Inflammatory Response Syndrome
Wide variety of severe clinical insults manifested by 2 (dogs) or three (cats) of altered parameters (see one note for table)
Look at: HR, Temp, Resp. rate/ PaCO2 and WBCC

Question 14

What is Sepsis

Answer 14

As for SIRS plus infectious agent identified (assumed in veterinary)

Question 15

What is severe sepsis/SIRS

Answer 15

Sepsis (SIRS) associated with organ dysfunction, hypoperfusion, or hypotension

Question 16

What is multiple organ dysfunction syndrome (MODS)

Answer 16

Presence of altered organ function in an acutely ill patient such that homeostasis cannot be maintained without intervention
Last phase, normally just before death

Question 17

What is refractory (septic) shock/ SIRS shock

Answer 17

Subset of severe sepsis (SIRS)
Defined as sepsis (SIRS) induced hypotension despite adequate fluid resuscitation
Patients receiving inotropic or vasopressors may no longer be hypotensive yet they would still be considered to have septic (SIRS) shock

Question 18

What is hypovolaemic shock

Answer 18

Decreased circulating blood volume
- Fluid loss from intravascular space
- Trauma
- Haemorrhage

Question 19

What is cardiogenic shock

Answer 19

Decreased forward flow from the heart
- Congestive heart failure
- cardiac dysrhythmias
- cardiac tamponade (compression of heart)
- Drug overdose (anaesthetic agents, beta-blockers, calcium channel blockers)

Question 20

What is distributive shock

Answer 20

Loss of systemic vascular resistance
- sepsis
- obstruction (saddle thrombis, heartworm)
- anaphylaxis

Question 21

What is metabolic shock

Answer 21

Deranged cellular metabolic machinery
Hypoglycaemia
Cyanide toxicity
Mitochondrial dysfunction
Cytopathic hypoxia of sepsis

Question 22

What is hypoxaemic shock

Answer 22

Decreased oxygen content in arterial blood
- Anaemia
- Severe pulmonary disease
- Carbon monoxide toxicity
- Methaemoglobinaemia

Question 23

What is cryptic shock

Answer 23

Normal global circulation/ parameters but poor microcirculation- oxygen and glucose transport from capillaries into cells
- SIRS
- Sepsis

Question 24

What is most common type of shock

Answer 24

Combines
Commonly hypovolaemic and distributive (and cryptic)

Question 25

Most common mechanisms causing reduced oxygen delivery

Answer 25

Loss of intravascular volume (hypovolaemic shock) Maldistribution of vascular volume (distributive and cryptic shock) Failure of the cardiac pump (cardiogenic shock)

Question 26

Examples of underlying diseases taht casue hypovolaemia

Answer 26

Blood loss- internal or external Loss of other body fluids- burns, Diarrhoea. vommiting etc.

Question 26

Examples of underlying diseases taht casue hypovolaemia

Answer 26

Blood loss- internal or external Loss of other body fluids- burns, Diarrhoea. vommiting etc.

Question 27

How does the heart compensate in hypovolaemic shock

Answer 27

Dec CO – reduced venous return triggers compensatory mechanisms Increased sympathetic activity Vasoconstriction Inc contractility Increased HR CO=SVxHR

Question 28

Compensatory mechanisms to increase IV volume in hypovolaemic shock (venous and renal)

Answer 28

Extreme vasoconstriction and changes in microcirculation- mobilisation of fluid from interstitial and extracellular spaces to IV space Decreased renal circualtion -> activates RASS -> upregulated SNS -> Na and H2O retention due to increased aldosterone and ADH

Question 29

Signs of compensated shock

Answer 29

Mild to moderate depression Tachycardia with normal to prolonged CRT Cool extremities Tachypnoea Normal blood pressure Pulse quality normal

Question 30

Signs of decompensated shock

Answer 30

Compensatory mechanisms inadequate and fail Pale mucous membranes Poor peripheral pulse quality Depressed mentation Fall in blood pressure

Question 31

What is oliguria

Answer 31

Low urine output

Question 32

Does sepsis lead to hypovolaemic shock

Answer 32

no leads to distributive shock

Question 33

what is the hyperdynamic phase of shock

Answer 33

Abnormally increased circulatory volume

Question 34

Signs of hyperdynamic phase of sock

Answer 34

tachycardia fever bounding peripheral pulses hyperaemic (increase blood flow) mucous membranes secondary to cytokine (NO) mediated vasodilation Also referred to as vasodilatory shock

Question 35

Shock organ for dogs

Answer 35

GI tract see ileus, diarrhoea and melaena

Question 36

what is melaena

Answer 36

the production of dark sticky faeces containing partly digested blood, as a result of internal bleeding or the swallowing of blood.

Question 37

What is shock organ of cat

Answer 37

lungs Rarely see hyperdynamic phase Changes in heart rate unpredictable cf dogs/horses- tachy or bradycardia!! Pale/icteric MM, weak pulses, cold extremities, hypothermia and generalised weakness/ collapse

Question 38

What is shock organ of cow

Answer 38

GI- same as dog

Question 39

How can pulse be used to estimate stroke volume

Answer 39

Stroke volume is the amount of blood ejected by the heart with each beat. The pulse and stroke volume are related, and changes in pulse can give an estimation of stroke volume. by measuring the pulse and assessing its strength, it is possible to estimate the stroke volume. This is often done using a technique called pulse pressure analysis, which involves measuring the difference between the systolic blood pressure (the highest pressure generated by the heart during a contraction) and diastolic blood pressure (the lowest pressure between contractions). The pulse pressure is then used as an indicator of stroke volume.

Question 40

What is cytopathic hypoxia

Answer 40

Cytopathic hypoxia is a type of tissue hypoxia that can occur in sepsis, In sepsis, the body's immune system releases a variety of chemicals that can damage the lining of blood vessels, leading to a decrease in blood flow to vital organs such as the lungs, liver, and kidneys -> the cells in these organs are unable to use the available oxygen to produce energy due to damage to their internal machinery caused by the immune system chemicals. This leads to cellular dysfunction and can contribute to the development of organ failure in sepsis. it is thought to involve a combination of factors, including impaired mitochondrial function, altered metabolic pathways, and oxidative stress. Treatment of sepsis typically involves aggressive management of the underlying infection, supportive care, and interventions to improve tissue oxygenation and prevent organ dysfunction