EAC Clinical Shock

Question 1

define:

Shock

Answer 1

Shock is characterised by impaired cellular function as a result of a reduction in effective circulating blood volume

Question 2

three intact mechanisms the body requires to function normally

Answer 2

Effective heart (pump)

Intact and functioning blood vessels (pipes)

Adequate volume of blood (fluid)

Question 3

pathophysiology of shock

Answer 3

Insufficient O2 for aerobic metabolism

Cells produce energy via anaerobic metabolism

inefficient process resulting in excess lactic acid

Shock = this failure of energy production

Question 4

define:

Hypovolemic Shock

Answer 4

Inadequate volume of blood

Question 5

define:

Cardiogenic Shock

Answer 5

Failure of heart (pump)

Question 6

define:

Neurogenic Shock

Answer 6

Loss of vasomotor tone

Question 7

define:

Septic Shock

Answer 7

Septicaemia

Question 8

causes of:

Hypovolemic Shock

Answer 8

Whole blood loss - internal/external bleeding

Plasma loss - burns

Electrolyte/Water loss - D and V

Question 9

causes of:

Cardiogenic Shock

Answer 9

Heart failure

MI

Myocarditis

Tension pneumothorax

Cardiac tamponade

Question 10

causes of:

Neurogenic Shock

Answer 10

High spinal cord injury - blood vessels relax dropping BP

Poisons

Fainting

Question 11

causes of:

Septic Shock

Answer 11

meningococcal meningitis

Peritonitis

Cardiac conditions e.g. myocarditis

Question 12

compensatory mechanism for:

Hypovolemic Shock

Answer 12

Sympathetic nerves increase venous tone

Reserve blood volume is mobilised from peripheral veins

Reduction in total circulatory capacity

in these ways the body tries to match the available blood volume.

Question 13

compensatory mechanism for:
Hypovolemic Shock

If this is not adequate:

Answer 13

Heart rate will increase flow to vital organs

Selective constriction or arteries supplying non-vital organs to reduce their share of the lowered cardiac output (CO=SVxHR)

As venous return continues to fall, right heart filling is impaired and stroke volume reduced

Heart becomes unable to refill adequately between its contractions and fails to perfuse the heart muscle itself

Cardiac arrest and death could follow

Question 14

Hypovolemic Shock Stage 1

Answer 14

Upto 15% blood volume loss

Normal RR 12-20

Pallor of skin

Normal capillary refill

Pulse rate >100bpm

No change in systolic or diastolic BP

Question 15

Hypovolemic Shock Stage 2

Answer 15

15-30% blood volume loss

Increased RR 15-30/min

Pallor, cool, clammy skin

Extended time for capillary refill

Pulse rate >100bpm

Normal systolic BUT elevated diastolic BP (narrowing pulse)

Question 16

Hypovolemic Shock Stage 3

Answer 16

30-40% blood volume loss

Anxiety, restlessness and agitation

Increased RR 30-40/min

Pulse rate >120bpm

Falling systolic BP to 100mmHg or less

Question 17

Hypovolemic Shock Stage 4

Answer 17

Over 40% blood volume loss

Moribund appearance

Signs of respiratory distress 40+/min

Central cyanosis

Altered level of consciousness

Marked tachycardia/weak pulse

Systolic BP 70mmHg or less

Question 18

additional considerations for shock in a pregnant patient

Answer 18

Signs of shock appear late in pregnant pt’s

Hypotension is an extremely late sign indication stage 3 shock

Consider pt position onto left side due to foetal compression on the inferior vena cava

HR is increased by 10-15BPM during pregnancy

BP falls 10-15mmHg during pregnancy

Cardiac output increases 20-30% during first 10 weeks of pregnancy

Blood volume increases during pregnancy, but unproportionately causing anaemia

Question 19

management of:

Shock

Answer 19

DRABCDE
Assess for time critical
High % O2
If conscious: position flat with head and shoulders slightly raised
If unconscious: in stable side position
Raise lower limbs
Treat other injuries and bleeding
Do not overheat or allow to become cold
Avoid rough handling, be gentle
Constant reassurance
Constant Observations
Nil by mouth
Time critical transfer to appropriate facility - pre alert
Consider paramedic/HEMS help

Question 20

Considerations for early paramedic/HEMS intervention for Shocked patients

Answer 20

Immediate surgery

Better pain relief

Paramedic/HEMS drugs - coagulant