Systemic Response to Injury

Question 1

Identifiable source of microbial insult

Answer 1

Infection

Question 2

SIRS

Answer 2

Two or more of following criteria are met:

1. Temperature
   ≥38°C (100.4°F) or≤36°C (96.8°F)
2. Heart rate
   ≥90 beats per minute
3. Respiratory rate
   ≥20 breaths per minute

or Paco2 ≤ 32 mmHg or mechanical ventilation

4. Abnormal white blood cell count
   (≥12,000/μL or ≤4000/μL or ≥10%immature band forms)

Question 3

Identifiable source of infection + SIRS

Answer 3

Sepsis

Question 4

Sepsis + organ dysfunction

Answer 4

Severe Sepsis

Question 5

Sepsis + cardiovascular collapse (requiring vasopressor support)

Answer 5

Septic shock

Question 6

Traumatic injury results in complex neuroendocrine signaling from the brain.
The two principle neuroendocrine pathways that orchestrate the host response are the

Answer 6

hypothalamic-pituitary-adrenal (HPA) axis,
-which results in the release of glucocorticoid hormones,

and the sympathetic nervous system,
-which results in release of the catecholamines, epinephrine (EPI), and norepinephrine (EPI).

Question 7

Following injury, corticotrophin-releasing hormone (CRH) is secreted from the

Answer 7

paraventricular nucleus (PVN) of the hypothalamus

Question 8

ACTH acts on the _____________ to synthesize and secrete glucocorticoids (Fig. 2-3).
Cortisol is the major glucocorticoid in humans and is essential for survival during significant physiologic stress.

Answer 8

zona fasciculate of the adrenal glands

Question 9

activated in response to stress and tissue hypoxiaby hypoxia-inducible factor 1α (HIF1A)

Answer 9

phenylethanolamine N-methyltransferase (PNMT) transcription

Question 10

Aldosterone is a mineralocorticoid released by the

Answer 10

zona glomerulosa of the adrenal cortex

Question 11

It is a mechanism by which ERdistress signals are sent to the nucleus to modulate transcriptionin an attempt to restore homeostasis.

Answer 11

Unfolded protein response (UPR)

Question 12

a way of disposing of damaged organelles and debris aggregates that are too large to be managed by proteosomal degradation.

Answer 12

“macroautophagy” (autophagy)

Question 13

An energy-dependent, organized mechanism for clearing senescent or dysfunctional cells, including macrophages, neutrophils, and lymphocytes, without promoting an inflammatory response.

Answer 13

Apoptosis

Question 14

Apoptosis proceeds primarily through two pathways:
the extrinsic pathway and the intrinsic pathway.
This pathway is activated through the binding of death receptors

Answer 14

Extrinsic pathway

Question 15

Apoptosis proceeds primarily through two pathways:
the extrinsic pathway and the intrinsic pathway.
This pathway is activated through protein mediators

Answer 15

Intrinsic pathway

Question 16

refers to the premature uncontrolled death ofcells in living tissue typically caused by accidental exposure to external factors, such as ischemia, inflammation or trauma, which result in extreme cellular stress.

Answer 16

Cellular necrosis

Question 17

form of regulated cell death that is dependent on the activity of the proinflammatory caspase enzymes associated with the inflammasome

Answer 17

Pyroptosis

Question 18

a potent inflammatory mediator that is rapidly mobilized inresponse to stressors such as injury and infection.
It is primarily synthesized by immune cells, such as macrophages, dendritic cells, and T lymphocytes

Answer 18

TNFa

Question 19

Among earliest responders after injury; half-life <20 min; activates TNFreceptors 1 and 2; induces significant shock and catabolism

Answer 19

TNFa

Question 20

Induces fevers through prostaglandin activity in anterior hypothalamus; promotes β-endorphin release from pituitary;
half-life <6 min

Answer 20

IL-1

IL-1 α and IL-1 β

Question 21

Promotes lymphocyte proliferation,
immunoglobulin production,
gut barrier integrity; half-life <10 min;
attenuated production after major blood loss leads to immunocompromise; regulates lymphocyte apoptosis

Answer 21

IL-2

Question 22

Elicited by virtually all immunogenic cells; long half-life; circulating levels proportional to injury severity;

prolongs activated neutrophil survival

Answer 22

IL-6

Question 23

levels elevated in sepsis, particularly gram-positive infections;

high levels found in cardiac deaths

Answer 23

IL-18

Question 24

Induces “sickness behavior”

Answer 24

HMGB1

Question 25

The major precursor of ________ is the omega-6(n-6) polyunsaturated fatty acid (PUFA) linolenic acid

Answer 25

arachidonic acid

Question 26

Eicosanoids generated from AA include

Answer 26

prostaglandins,thromboxanes, and leukotrienes.

Question 27

Serotonin is a monoamine neurotransmitter (5-hydroxytryptamine; 5-HT) derived from

Answer 27

tryptophan

Question 28

are among the first responders to sites ofinfection and injury and as such are potent mediators of acuteinflammation

Answer 28

Neutrophils (PMNs)

Question 29

main effector cells that sense and respond to “danger signals,”primarily through mechanisms that include phagocytosis of cellular debris, release of inflammatory mediators, and recruitment of additional immune cells to injury sites.

Answer 29

monocytes/macrophages

Question 30

are the most important antigen-presenting cells (APCs) for initiating T-cell responses against protein antigens

Answer 30

Dendritic cells

Question 31

was initially known as endothelium-derivedrelaxing factor due to its effect on vascular smooth muscle.

Answer 31

Nitric oxide (NO)

Question 32

To maintain basal metabolic needs (i.e., at rest and fasting), a normal healthy adult requires approximately

Answer 32

22 to 25 kcal/kg per day