Fiser ABSITE Ch. 16 Critical Care Flashcards Preview

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Flashcards in Fiser ABSITE Ch. 16 Critical Care Deck (112):
1

What is the normal range for CO?

4-8 L/min

2

What is the normal range for Cardiac Index?

2.5-4

3

What is the normal range for systemic vascular resistance? and systemic vascular resistance index?

800-1400, 1500-2400

4

What is the normal PCWP?

11 +- 4

5

What is the normal CVP?

7 +- 2

6

What is the normal pulmonary artery pressures?

20-30/6-15

7

What is the normal mixed venous oxygen saturation SvO2?

75+-5

8

What percentage of CO does the following organs get? kidney, brain, heart

25, 15, 5 respectively

9

What is the formula for MAP?

CO x SVR

10

What is the formula for ejection fraction?

stroke volume/EDV

11

Cardiac output increases with HR up to 120-150 bpm, then starts to go down, why?

decreased diastolic filling time

12

Atrial kick accounts for what % of LVEDV?

15-30%

13

Automatic increase in contractility secondary to increase in afterload. What is this effect called? What about automatic increase in contractility secondary to increased HR?

Anrep effect

Bowditch effect

14

What is the normal O2 delivery-to-consumption ratio? What increases to keep this ratio constant?

5:1, CO

15

What is the normal SvO2?

75%

16

What measurement can be thrown off by pulmonary htn, aortic regurg, mitral stenosis, mitral regurg, high PEEP, porr LV compliance?

Wedge

17

What is the only way to measure pulmonary vascular resistance?

swan

18

Which zone of the lung do you place a swan?

zone III (lower lung)

19

Hemoptysis after flushing Swan. Name three interventions.

increase PEEP to tamponade the pulmonary artery bleed,
mainstem intubate the nonaffected side,
try to place a Fogarty down the affected side,
may need thoracotomy and lobectomy

20

Name two relative contraindications to a swan.

previous pneumonectomy, LBBB

21

In this pulmonary artery wedge tracing, wedge pressure is measured at end expiration. Which point is for spontaneous breathing pts and which is for pts undergoing positive pressure ventilation?

//fce-study.netdna-ssl.com/images/upload-flashcards/154221/870299_m.png\\A is for spontaneous, B is for vent

22

What are the two primary determinants of myocardial O2 consumption -> can lead to myocardial ischemia?

increased ventricular wall tension and HR

23

Why is LV blood 5 mmHg of PO2 lower than pulmonary capillaries?

unsaturated bronchial blood empties into pulmonary veins

24

What is the normal alveolar-arterial gradient in a non ventilated pt?

10-15 mmHg

25

Where is blood with the lowest venous saturation located?

coronary venous blood (30%)

26

Cardiovascular collapse; characteristically unresponsive to fluids and pressors.

Acute adrenal insufficiency

27

hyperpigmentation, weakness, weight loss, GI sx, increased K, decreased Na, fever, hypotension.

chronic adrenal insufficiency

28

Steroid potency:
1x - cortisone, hydrocortisone
___ - prednisone, prednisolone, methylprednisolone
___ - dexamethasone

5x; 30x

29

Neurogenic shock - loss of sympathetic tone. Usually have decreased HR, decreased BP, warm skin. Tx?

give volume 1st, then phenylephrine after resuscitation; give steroids for blunt spinal trauma with deficit

30

What is the initial alteration in hemorrhagic shock?

increased diastolic pressure

31

What is the tx for cardiac tamponade?

fluid resuscitation initially; need pericardial window or pericardiocentesis

32

What is the CO and SVRI in hemorrhagic shock (increased or decreased)? and septic shock?

CO is decreased, SVRI is increased in hemorrhagic shock; CO is increased, SVRI is decreased in septic shock

33

What is the triad of hyperventilation, confusion and respiratory alkalosis?

early sepsis triad

34

What is the insulin and glucose in early vs late gram-negative sepsis?

Early is decreased insulin and increased glucose due to impaired utilisation; Late is increased insulin and increased glucose due to insulin resistance

35

When does hyperglycemia occur in sepsis?

just before pt becomes clinically septic

36

What is activated protein C (Xigris) used for and what is the mechanism?

used for sepsis; mechanism is fibrinolysis

37

What stain can be used to find fat in sputum in urine to help dx fat emboli?

sudan red

38

PA systolic pressures >40, decreased PO2 and PCO2, respiratory alkalosis, chest pain, cough, dyspnea, increased HR

PE

39

What is the tx for air emboli?

place pt head down and roll to left to keep air in RV and RA then aspirate air out with central line or PA catheter to RA/RV

40

When is IABP used? what is the contraindication? what does it improve?

cardiogenic shock, aortic regurgitation, improves coronary perfusion

41

Name the receptor: vascular smooth muscle constriction; gluconeogenesis, glycogenolysis

Alpha 1

42

Name the receptor: venous smooth muscle constriction

Alpha 2

43

Name the receptor: mycocardial contraction and rate

Beta 1

44

Name the receptor: relaxes bronchial smooth muscle, relaxes vascular smooth muscle; increases insulin, glucagon, rennin

Beta 2

45

Name the receptor: relax renal and splanchnic smooth muscle

dopamine

46

Name the three receptors and associated effects for dopamine at low (0-5 ug/kg/min), medium (6-10), and high (>10) doses.

low - dopamine receptors (renal)
medium - beta-adrenergic (heart contractility)
high - alpha-adrenergic (vasoconstriction and increased BP)

47

What receptors and affects does dobutamine affect at low (5-15 ug/kg/min) and high (>15) doses.

low - beta-1 (increased contractility)
high - beta 2 (vasodilation, increased HR)

48

Name the drug that is a phosphodiesterase inhibitor (Increases cAMP). Results in increased Ca flux and increased myocardial contractility. Also causes vascular smooth muscle relaxation and vasodilation.

Milrinone

49

What receptor does Phenylephrine affect?

alpha-1, vasoconstriction

50

What receptors does Norepinepherine affect at low and high doses?

Low - beta-1 (increased contractility); High - alpha-1 and alpha-2

51

What receptors does Epinephrine affect at low and high doses?

Low - beta 1 and beta 2 (increased contractility and vasodilation). Can decrease BP at low doses.
High - alpha-1 and alpha-2 (vasoconstriction). Increased cardiac ectopic pacer activity and myocardial O2 demand.

52

Name the drug that hits Beta-1 and beta-2 receptors, increasing HR and contractility, vasodilates. Side effects: extremely arrhythmogenic; increased heart metabolic demand (rarely used); may actually decrease BP.

Isoproterenol

53

Name the Vasopressin receptor: vasoconstriction of vascular smooth muscle

V-1

54

Name the Vasopressin receptor: water reabsorption at collecting ducts

V-2 (intrarenal)

55

Name the Vasopressin receptor: mediate release of factor VIII and vWF

V-2 (extrarenal)

56

What is the concern with Nipride (arterial and venous dilator)?

Cyanide toxicity at doses ?3 ug/kg/min for 72 hrs; check thiocyanate levels and signs of metabolic acidosis

57

How does nitroglycerin decrease myocardial wall tension?

decreasing preload

58

What is the MOA of hydralazine?

alpha blocker

59

What is the formula for compliance? What does high compliance lungs mean?

change in volume/change in pressure.
easy to ventilate

60

Pts with ARDS, fibrotic lung disease, reperfusion injury, pulmonary edema all have reduce what?

pulmonary compliance

61

Which part of the lungs has the highest V/Q ratio? the lowest?

highest in upper, lowest in lower

62

On a ventilator what can be increased to improve oxygenation (alveoli recruitment) -> improves FRC

increased PEEP

63

On a ventilator what 2 things can be increased to decrease CO2?

increased rate or volume

64

Normal weaning parameters:
negative inspiratory force (NIF) > ___,
FiO2 ___
PCO2 ___

negative inspiratory force (NIF) > 20,
FiO2 60
PCO2 93%
off pressors,
follows commands,
can protect airway

65

Barotrauma on vent - high risk if plateus >___ and peaks >___ -> consider prophylactic ___

30,50, chest tubes

66

What does pressure support on a vent do?

decreases the work of breathing (inspiratory pressure is held constant until minimum volume is achieved)

67

Excessive PEEP complications include decreased RA filling, decreased CO, decreased renal blood flow and decreased urine output and increased ___

pulmonary vascular resistance

68

What 3 types of pts where high frequency ventilation is used?

kids, tacheoesophageal fistula, bronchopleural fistula

69

Why is inverse ratio ventilation used? (normal 1:2 I:E phase; go to 2:1)

helps reduce barotrauma

70

What is the formula for minute ventilation?

TV x RR

71

What class of lung disease is represented by decreased TLC, decreased RV, decreased FVC, FEV1 can be normal or increased?

restrictive lung disease

72

What class of lung disease is represented by increased total lung capacity, increased residual volume and decreased FEV1?

obstructive lung disease

73

What is the most common cause of ARDS?

sepsis

74

Acute Lung Injury is defined by acute onset, bilateral pulmonary infiltrates, PaO2/FiO2

PaO2/FiO2

75

What two cytokines mediate SIRS?

TNF-alpha and IL-1

76

What are the 4 SIRS criteria?

Temp >38 or less than 36
RR >20 or Pco2 12,000 or 90

77

SIRS -> Sepsis -> Septic Shock -> ___

MOD (Progressive but reversible dysfunction of 2 or more organs arising from an acute disruption of normal homeostasis)

78

What is the name of the syndrome of chemical pneumonitis from aspiration of gastric secretions.

Mendelson's

79

Most common cause of fever in the first 48 hours after operation?

atelectasis

80

What effect does the following have on the lungs? bradykinin, PGEi, prostacyclin (PGI2), nitric oxide

pulmonary vasodilation

81

What effect does the following have on the lungs? histamine, serotonin, TXA2, epinephrine, norepinephrine, hypoxia, acidosis

pulmonary vasoconstriction

82

What effect does alkalosis have on pulmonary vasculature? and acidosis?

alkalosis - pulmonary vasodilator
acidosis - pulmonary vasoconstrictor

83

What does nitroprusside, nitroglycerine, and nifedipine do to the pulmonary vasculature?

pulmonary shunting

84

What is the most common cause of postoperative renal failure?

hypotension

85

What percentage of nephrons need to be damaged before renal dysfunction occurs?

70%

86

What is the best test for azotemia?

FeNa

87

What are the three steps to treating Oliguria?

1st make sure pt is volume loaded (CVP 11-15 mmHg), 2nd try diuretic trial (Lasix or butanamide); 3rd dialysis if needed

88

Renin is released in response to decreased pressure sensed by ___ in kidney. Also in response to increased Na concentrations sensed by ___

juxtaglomerular apparatus, macula densa

89

What does renin do?

converts angiotensinogen to angiotensin I

90

What converts angiotensin I to angiotensin II?

angiotensin converting enzyme in the lung

91

What structure releases aldosterone in response to angiotensin II?

adrenal cortex

92

What specifically does aldosterone do to the kidney?

Acts on distal convoluted tubule ATPase to increase resorption of water and sodium and secretion of potassium.

93

What does atrial natriuretic peptide do to the kidney? to the blood vessels?

inhibits Na and water resorption at the collecting ducts; vasodilator

94

What specifically does ADH do to the kidney? the blood vessels?

Acts on the collecting ducts for water resorption; vasoconstrictor

95

How do NSAIDs cause renal damage?

Inhibit prostaglandin synthesis, resulting in renal arteriole vasoconstriction

96

How do aminoglycosides cause renal damage?

direct tubular injury and later renal vasoconstriction

97

Myoglobin causes direct renal tubular injury. What is the tx?

alkalinize urine

98

Contrast dyes cause direct tubular injury. What is the tx?

premedicate with N-acetylcysteine and volume

99

The following things preclude what diagnosis?
uremia, temp

brain death

100

How long must the following exist to declare brain death:
unresponsive to pain, absent caloric oculovestibular reflexes, absent oculocephalic reflex, positive apnea test, no corneal reflex, no gag reflex, fixed and dilated pupils.

6-12 hours

101

What two testing modalities can be used to prove absence of brain activity?

EEG - electrical silence; MRA - will show no blood flow to brain

102

Apnea test - disconnected from ventilation; CO2 >___ mm Hg or increase in CO2 by ___ is a positive test for apnea. If arterial pressure drops to

60, 20

103

Can you still have deep tendon reflexes with brain death?

yes

104

What does carbon monoxide do to a pulse oximeter?

Can falsely increase reading

105

What does carbon monoxide do to hemoglobin?

binds hemoglobin directly creating carboxyhemoglobin

106

What is an abnormal carboxyhemoglobin level? and in smokers?

>10%, >20%

107

What is tx for carbon monoxide poisoning?

100% O2 on a ventilator; may need hyperbaric O2 if really high

108

Methemoglobinemia can occur from nitrites such as Hurricaine spray; nitrites bind Hgb. What is the O2 saturation? What is the tx?

85%, methylene blue

109

Critical illness polyneuropathy - motor > sensory neuropathy; occurs with ____; can lead to failure to wean from ventilation

sepsis

110

In endothelial cells, forms toxic oxygen radicals with reperfusion, involved in reperfusion injury. Also involved in the metabolism of purines and breakdown to uric acid

Xanthine oxidase

111

When do seizures occur with ETOH withdrawal?

48 hrs

112

ICU (or hospital) psychosis generally occurs after which postoperative day? What do you need to rule out?

3rd, metabolic and organic causes