hemodynamics part 5

Question 1

define Shock

Answer 1

clinical manifestations of the inability ofthe circulatory system to adequately supply tissues with nutrients and remove toxic waste
- inadequate blood flow secondary to decreased cardiac output or mal-distributed output that results in irreversible tissue damage

Question 2

describe the sequela of shock

Answer 2

1) reduction in cardiac output or effective circulating volume
2) hypotension develops
3) impaired tissue perfusion
4) cellular HYPOXIA

Question 3

define neurogenic shock

Answer 3

• neurogenic dysfunction causes loss of vascular tone and peripheral pooling of blood

Question 4

define anaphylactic shock

Answer 4

• generalized IgE mediated hypersensitivity response associated with vasodilation and increased vascular permeability

Question 5

describe the five unifying features of shock

Answer 5

• intracellular calcium overload
• intracellular hydrogen ion
• celllular and intestitial edema
• catabolic metabolism (breaking down)
• inflammation

Question 6

rosen’s empiric criteria for the diagnosis of shock

Answer 6

• Ill appearance or decreased LOC
• HR > 100
• RR > 22 or PC02 < 32
• base deficit < -5 or lactate > 4
• Urine output < .05 ml/kg/hr
• Hypotension > 20 minute duration
  NEED 4 OUT OF 6 CRITERIA
  –> can be in shock without being hypotensive

Question 7

describe the 3 stages of shcok

Answer 7

1) nonprogressive stage = reflex compensation; mechanisms maintain tissue perfusion
2) Progressive stage = worsening circulatory/metabolic imbalance; acidosis
3) irreversible stage = irreversible tissue damage

Question 8

describe progressive phase

Answer 8

• widespread tissue hypoxia
• lactic acidosis causes decreased vasomotor response:
• -> arterioles dilate leads to pooling in microcirculation worsens cardiac output
• -> anoxic endothelial cell injury
• confusion and decreased urinary output

Question 9

describe irreversible stage

Answer 9

• widespread cell injury
• -> lysosmal enzyme leakage
• -> decreased myocardial contraction
• -> acute tubular necrosis leads to renal failure
• subsequent decrease in urine output and severe fluid/electrolyte disorders occur

Question 10

describe nonprogressive phase

Answer 10

• maintain blood pressure and cardiac output through various reflexs:
• -> baroreceptor reflexes
• -> catecholamine release
• -> activation of renin-angiotensin-axis
• -> antidiuretic hormone release
• -> general sympathetic stimulation

Question 11

describe cardiogenic shock

Answer 11

• decreased cardiac output and evidence of tissue hypoxia in presence of adequate intravascular volume
• CRITERIA
• -> hypotension x30min
• -> 30 mm HG below baseline
• -> cardiac index < 2.2L/min/m2
• -> PCWP > 15mmHg
• -> or Rosen’s 4 out of 6 criteria for empiric shock
• Will have lost 40% of myocardium

Question 12

how do you go about treating someone with cardiogenic shock

Answer 12

• stabilize the ABCs
• identify etiology of cardiogenic shock
• small fluid bolus (250cc)
• don’t by shy on fluids if RB infarct
• norepinephrine or dopamine = vasopressors
• dobutamine is used to increase cardiac output
• manage infarct

Question 13

describe hemorrhagic shock

Answer 13

• severe hypotension due to blood loss