Systemic Response to Injury Flashcards Preview

Surgery > Systemic Response to Injury > Flashcards

Flashcards in Systemic Response to Injury Deck (80):
1

Protein signaling compounds that mediate cellular responses

Cytokines

2

Cytokine: Induces muscle breakdown and cachexia through increased catabolism

TNF-α

3

Cytokine: Induces fever through prostaglandin activity in anterior hypothalamus

IL-1

4

Cytokine: Promotes β-endorphin release from pituitary

IL-1

5

Cytokine: Promotes lymphocyte proliferation and Ig production

IL-2

6

Cytokine: Elicited by all immunogenic cells as a mediator of acute phase response

IL-6

7

Cytokine: Prolongs activated neutrophil survival

IL-6

8

Cytokine: Chemoattractant for neutrophils, basophils, eosinophils, and lymphocytes

IL-8

9

Cytokine: Activates macrophages via Th1 cells

IFN-γ

10

Protect cells from deleterious effects of traumatic stress and, when released by damaged cells, alert the immune system of the damage

Heat shock proteins

11

Bind both autologous and foreign proteins and thereby function as intracellular chaperones for ligands such as bacterial DNA and endotoxin

Heat shock proteins

12

Cause cell injury through oxidation of unsaturated fatty acids within cell membranes

ROS

13

Derived primarily by oxidation of membrane phospholipid arachidonic acid

Eicosanoids

14

Enzyme involved in the oxidation of membrane phospholipid arachidonic acid

PLA2

15

Action of phospholipase A2 is inhibited by

Corticosteroids

16

Arachidonic acid undergoes the COX pathway to generate (2)

Cyclic endoperoxidases
1) PG
2) TXA2

17

Arachidonic acid undergoes the LOX pathway to generate (2)

HPETE (5-Hydroperoxyeicosatetraenoic acid)
1) HETE (5-Hydroxyicosatetraenoic acid)
2) Leukotrienes

18

MOA of Aspirin (NSAID prototype)

Nonselectively and irreversibly inhibits COX (COX-1 and 2)

19

Aspirin anti-inflammatory effect is mediated by

Inhibition of COX-2 thereby inhibition of TXA2 production by platelets and decreases platelet aggregation

20

GI toxicity of NSAIDs is mediated by

Inhibition of COX-1 hence PG synthesis (for HCO3 and mucous secretion)

21

A viral illness for which aspirin is used is associated with what syndrome in children

Reye syndrome

22

Reye syndrome is characterised by (2)

Acute non-inflammatory
1) Encephalopathy
2) Fatty degenerative liver failure

23

Nonselective but reversible COX inhibitors (2)

1) Indomethacin
2) Ketorolac

24

Selective COX-2 inhibitor with reduced risk of GI toxicity

Celecoxib

25

Anti-inflammatory effect of omega 3 fatty acids (3)

1) Inhibits TNF release from hepatic Kupffer cells
2) Inhibits leukocyte adhesion
3) Inhibits leukocyte transmigration

26

Elevated during G- bacteremia, hypotension, hemorrhage, endotoxemia, and tissue injury

Kallikrein

27

Action of kinins (6)

1) Vasodilation
2) Increased capillary permeability
3) Tissue edema
4) Pain pathway activation
5) Inhibition of gluconeogenesis
6) Increased bronchoconstriction

28

Actions of serotonin

1) Vasoconstriction
2) Bronchoconstriction
3) Platelet aggregation

29

Associated with eosinophil and mast cell chemotaxis

Histamine (H4)

30

PSY nervous system transmits its efferent signals via

Acetylcholine

31

Vagus nerve potentially regulates early pro inflammatory mediator release, specifically

TNF

32

CNS regulates inflammation via

Vagus nerve

33

Stimulus for cortisol release

ACTH

34

In burn-injured patients, cortisol may be chronically elevated for how long

4 weeks

35

Cortisol impairs wound-healing by reducing what substances in the wound

1) TGF-β
2) IGF-I

36

Principal regulator of steroid synthesis

ACTH

37

Sequence in steroid synthesis (3)

1) Cholesterol converted to pregnenolone by ACTH
2) Pregnenolone converted to progesterone or 17α-OH-pregnenolone
3) Progesterone converted to 11-Deoxycorticosterone to corticosterone to aldosterone (mineralocorticoid)
3) Progesterone converted to 17α-OH-prrogesterone to 11-deoxycortisol to cortisol (glucocorticoid)
3) 17α-OH-pregnenolone converted to DHEA to androstenedione to testosterone to estradiol (sex steroid)

38

A steroid alcohol

Cholesterol

39

Cholesterol is a precursor of (5)

1) Cell membranes
2) Vitamin D (7-dehydrocholesterol)
3) Bile salts (cholic and chenodeoxycholic acid)
4) Adrenal hormones (aldosterone and cortisol)
5) Sex hormones (testosterone and estradiol)

40

Cholesterol is composed of (2)

1) 4 fused hydrocarbon rings (A-D)
2) 8-membered branched hydrocarbon chain (20-27) attached to the D-ring
3) Single hydroxyl group at C3 of the A ring to which a fatty acid can be attached to form cholesterol esters

41

Counter regulatory mediator that potentially reverses the anti-inflammatory effects of cortisol

Macrophage Migration-Inhibiting Factor

42

MMIF is stored and secreted by (2)

1) Anterior pituitary
2) Intracellular pools within macrophages

43

GH exerts downstream effects through (2)

1) Direct interaction with GH
2) Enhanced hepatic synthesis of IGF-I

44

Actions of GH and IGF-I (3)

1) Protein synthesis
2) Insulin resistance
3) Mobilization of fat stores

45

Catecholamines

1) Epinephrine
2) Norepinephrine
3) Dopamine

46

Elevations of plasma catecholamine levels last ___ after severe injury

24-48h

47

Overall action of insulin

Anabolic state

48

Hallmarks of critical illness due to the catabolic effects of circulating mediators (2)

1) Insulin resistance
2) Hyperglycemia

49

T/F Hyperglycemia is associated with immunosuppression and increased risk for infection

T

50

Normal healthy adult requires how many calories per day

22-25 kcal/kg/day

51

Initial hours after surgical or traumatic injury are metabolically associated with (2)

1) Reduced total body energy expenditure
2) Urinary nitrogen wasting

52

Short-term fasting, # of days

Less than 5 days

53

Principal sources of fuel in healthy adult

Protein and lipids

54

Most abundant source of energy in healthy adult

Lipids

55

Rapidly and preferentially depleted fuel stores

Hepatic glycogen

56

Short-term fasting: Fall of serum glucose concentration within

Less than 16 hours

57

Recycling of peripheral lactate and pyruvate for hepatic gluconeogenesis is accomplished by

Cori cylce

58

Precursors for hepatic gluconeogenesis

1) Peripheral lactate
2) Peripheral pyruvate
3) Alanine from skeletal muscle

59

Cori cycle is also known as

Lactic acid cycle

60

Metabolic pathway involving conversion of lactate (from the skeletal muscle) into glucose and brought back to the muscle for utilization

Cori cycle

61

Energy expense of Cori cycle

4 ATP molecules

62

T/F Lactate production is sufficient to maintain systemic glucose need during short-term fasting

F

63

Short-term fasting: Source of substrate for hepatic gluconeogenesis when lactate is insufficient

Amino acids

64

Amount of protein that must be degraded daily to provide amino acids for hepatic gluconeogenesis

75 g/d for a 70 kg adult

65

Proteolysis during starvation results from

1) Decreased insulin
2) Increased cortisol

66

Proteolysis during starvation results in increased excretion of

Urinary nitrogen in urine

67

Amount of urinary nitrogen excreted in urine during starvation

>=30 g/day

68

Normal amount of urinary nitrogen excreted per day

7-10 g

69

Effect on proteolysis by prolonged fasting

Reduced to 20 g/d

70

Effect on urinary nitrogen excretion by prolonged fasting

2-5 g/day

71

Why proteolysis and urinary nitrogen excretion are decreased during prolonged fasting

Adaptation by vital organs by using ketone bodies as their principal source of fuel

72

Ketone bodies become an important source of fuel for the brain after how many days of fasting

2

73

Ketone bodies gradually become the principal source of fuel for the brain after how many days of fasting

24 days

74

Injuries that poses the highest energy demands (2)

1) Major burns
2) Sepsis/peritonitis

75

Principal source of energy during critical illness and stressed states

Lipids

76

Lipolysis in injury occurs mainly in response to

Catecholamine stimulation of hormone-sensitive TAG lipase

77

Injury and severe infections induce a state of

Insulin resistance

78

T/F Increase in plasma glucose level in injury is proportional to the severity of injury

T

79

T/F After injury, there is an increase in urinary nitrogen excretion

T

80

After an injury, loss of urinary nitrogen corresponds to a loss in lean body mass of ___% per day

1.5