Micro U2 L1.

Question 1

What is the leading cause of death in patients admitted to non coronary intensive care units

Answer 1

blood stream infections

Question 2

What is the incidence of severe sepsis in America?

Answer 2

300/100,000 people

Question 3

What is the mortality rate of severe sepsis? In the ICU specifically?

Answer 3

28-50%; 80% in the ICU

Question 4

Infection

Answer 4

presence of microorganisms in a normally sterile site

Question 5

Bacteremia

Answer 5

cultivatable bacteria in blood stream (may be transient and inconsequential; inconsistent correlation with severe sepsis)

Question 6

Systemic inflammatory response syndrome (SIRS)

Answer 6

systemic response to a stress. includes two of the following: 1. temp >38, 90; 3. RR >20 or PaC02 12,000 cells/mm3 or 10% immature band forms

Question 7

Sepsis

Answer 7

systemic response to infection. in US: if you have proven or clinically suspected infection, SIRS becomes sepsis

Question 8

Hypotension

Answer 8

systolic 40 from baseline (must have no other cause to be septic related)

Question 9

Severe sepsis

Answer 9

sepsis with associated dysfunction of organs distant from site of infection, hypoperfusion, or hypotension

Question 10

Septic shock

Answer 10

sepsis with hypotension despite adequate fluid resuscitation requires vasopressor therapy - perfusion abnormalities that may include lactic acidosis, oliguria, altered mental status, acute lung injury

Question 11

Is SIRS a normal response by the body?

Answer 11

NO - an ABNORMAL generalized inflammatory reaction in organs remote from the initial insult

Question 12

TLR4

Answer 12

plays a critical role in mediating SIRS and its severity - transmits the LPS recognition signal to the interior of the cell which then lead to signal transduction - promote production and secretion of molecules mediating the inflammatory response

Question 13

LPS

Answer 13

major component of cell wall of gram-negative bacteria - recognized by TLR4

Question 14

What recognizes gram + cells?

Answer 14

TLR2

Question 15

How can signaling through TLR4 be altered?

Answer 15

variation in # of alkyl chains in lipid A (reduced # = inhibitor of immune activation by gram - ) - bacteria can change # acyl chains in response to environment

Question 16

What are indicators of septic shock?

Answer 16

APC (modulator of coagulation and inflammation - interferes with plasminogen activation) and Antithrombin

Question 17

When does septic shock occur?

Answer 17

in the presence of both SIRS and infection (SIRS can occur without infection due to trauma, burns, pancreatitis, etc)

Question 18

Transient bacteremia

Answer 18

comes from tooth brushing, biopsy (comes quick and then is cleared)

Question 19

Intermittent bacteremia

Answer 19

comes from abscess, UTI, pneumonia - MOST COMMON for septic patients!! - clearance and recurrence cycle

Question 20

Persistent/sustained bacteremia

Answer 20

intravascular

Question 21

Infective endocarditis pathogenesis

Answer 21

damage to cardia endothelium -> deposition of platelets and fibrin -> organisms gain access to bloodstream and stick = colonization -> protective layer of fibrin and platelets matrix -> bacterial multiplication -> vegetation formation

Question 22

What are organisms associated with endocarditis?

Answer 22

staph aureus, followed by strep, then coagulase negative staph

Question 23

Who is at a high risk of developing IE?

Answer 23

IV drug abusers

Question 24

Mycotic aneurysm

Answer 24

result from damage to endothelial cells lining the arteries (aneurysm due to an infectious agent)

Question 25

Supprative thrombophlebitis

Answer 25

venous thrombosis associated with inflammation in the setting of bacteremia (need to remove intravenous catheters every 3 days to avoid this happening)

Question 26

Catheter associated bloodstream infections

Answer 26

indwelling catheter becomes colonized with bacteria - associated with staph and candida species

Question 27

What is a primary BSI? What are the primary BSIs?

Answer 27

primary BSI: BSI without a documented primary source of infection and source is from an intravascular site. Includes: infective endocarditis, myotic aneurysm, supprative thrombophlebitis, catheter associated bloodstream infections

Question 28

What is a secondary BSI? What are the secondary BSIs?

Answer 28

there is a documented portal of entry and/or a known associated site of infection. Includes UTIs, bacterial pneumonias, post surgical wound infections

Question 29

How is bacteremia detected?

Answer 29

culturing of blood

Question 30

What are consideration for blood cultures?

Answer 30

need 3 blood cultures sets over 24 hours - 20 mL total to be take (10 mL in aerobic bottle and 10 for anaerobic bottle) - usually takes 48 hours to detect - some weird ones can take 5 days

Question 31

What test can differentiate between infectious SIRS from noninfectious SIRS?

Answer 31

high procalcitonin level (>2 ng/mL)