Shock

Question 1

Shock - .1.

what is it?

Answer 1

Inadequate perfusion/blood flow to the body’s peripheral tissues/organs

Question 2

Shock: 2.

The rapid progression of shock

Answer 2

Question 3

The Rapid Progression of Shock

Answer 3

Inadequate prefusion = cell hypoxia = energy deficit = lactic acid accumulation and anaerobic metabolism & fall in pH

= metabolic acidosis = cell membrane dysfunction & failure of Na2+ pump = intracelluluar lysomeomes release - digestive enzymes ( efflux of postassium & influx of Na2+ & water)

Vasoconstriction = failure of pre-capillary sphincters - peripheral pooling of blood

Toxic substances enter circulation - capillary endothelium damaged - further destruction - dysfunction = cell death.

Question 4

What is Shock caused by? .3.

Answer 4

Caused by issues with the:

Pump: (heart)

Pipes: (blood vessels)

Volume: (blood)

Combination of sympathetic nervous system stimulation and organ dysfunction produce the signs of shock:

Question 5

3 Stages of Shock: .5.

Answer 5

Stage 1 = Compensated Shock - the body detects

low blood flow - activates systems to maintain/restore perfusion

inceased heart rate - vasoconstriction.

Stage 2 = Decompensated Shock - compensation fails, perfusion reduces, oxygen deprivation occurs.

Stage 3 = Irreversible Shock - shut down of organs, irreversible damage to organs and tissues.

Question 6

Types of Shock: .6.

CHASSOH

Answer 6

Cardiogenic shock - low cardiac output - inadequate pumping of the heart.

Hypovolemic Shock - inadequate intra-vascular volume, - haemorrage

Anaphylactic Shock - released mediators in responsee to severe reaction - vasodilation and bronchooconstriction.

Septic Shock - released mediators in response to severe infection.

Spinal Shock - loss of sympathetic nervous system

Obstructive Shock - obstruction of blood flow in/out of heart

Hypoadrenal Shock -inadequate levels of circulating cortisol

Question 7

Shock : 7.

Signs of Shock

Answer 7

Tachycardia

Cold & Clammy skin

Prolnged Capillary Refill time

Tachypnoea

Narrowed Pulse Pressure

Hypotension

Altered Level of Consciousness

Question 8

Shock: 8 - Cardiogenic Shock

Answer 8

= caused by heart being unable to pump adequately

= most common cause = acute Mycardial Infarction

= other causes include= acute value rupture, PE, dysrhythmia (VT), cardiac tamponade, myocarditis

= pt presents = pale, cold & tachycardic with signs of Pulmonary oedema.

Question 10

Cardiogenic Shock 2nd to poor LEFT ventricular Function

Answer 10

= common cause = acute ant antero-septal or antero-lateral STEMI

= assoc with pulmonary oedema

= shock WILL NOT repsonde to 0.9 NACL so give with caution

Question 11

Cardiogenic shock 2nd RIGHT ventricular failure

Answer 11

= caused by inaequate RIGHT vent function

=common cause - acute inf MI involving the right ventricle

=shock is likely to respond to 0.9% NACL

Question 12

Cardiogenic Shock improved outcomes

Answer 12

High mortality rate unless the underlying problem is corrected in a timely manner.

• initiate fibrinolytic therapy for STEMI
• Transport pt to cardiac catheter room

Adrenaline admistration is reserved for severe Cariogenic shock

need to weigh up the potential benefits of improving CO against the need of raising Myocardial O2 consumption and having tachydysrhythmia.

IV infusion is preferred over IV boluses as it reduces the adverse effects of adrenaline.

Question 13

Hypovolaemic Shock is?

Answer 13

Hypovolaemic shock is caused by inadequate intra-vascular volume.

See the ‘hypovolaemia from uncontrolled bleeding’ and ‘hypovolaemia from other causes’ sections.

Question 14

Anaphylactic Shock is?

Answer 14

Anaphylactic shock is caused by mediators released in response to a severe allergic reaction.

See the ‘anaphylaxis’ section.

Question 15

Hypoadrenal Shock - Adrenal Crisis is?

Answer 15

Hypoadrenal shock (also called adrenal crisis) is caused by inadequate levels of circulating cortisol. See the ‘hypovolaemia from other causes’ section and note the following:

The adrenal glands produce additional cortisol during times of physiological stress and this is important for a normal cardiovascular response to occur, however some clinical conditions may result in abnormal adrenal function. Examples include: congenital adrenal hypoplasia, Addison’s disease, previous pituitary surgery and those taking high daily doses of steroid.

Question 16

Distributive Shock is ?

Answer 16

The term distributive shock is sometimes used to describe shock states associated with dilated and leaky blood vessels. This is particularly associated with anaphylactic shock and septic shock. In reality, there is often a combination of contributing factors to the shock state. For example:

In both anaphylactic and septic shock there is a combination of vasodilation, leaky blood vessels (with loss of intra-vascular volume) and impaired heart function.

In cardiogenic shock associated with right ventricular infarction, there is a combination of impaired right ventricular function and impaired left ventricular filling (reduced left ventricular pre-load).