Clinical Implications of Infection

Question 1

Infection Define

Answer 1

invasion of and multiplication of microorganisms within the tissue of the host
requires that the pathogen be able to adhere to; colonize or invade the host cells
EXPOSURE TO PATHOGEN DOES NOT EQUAL INFECTION

Question 2

Types of pathogens

Answer 2

Bacteria
Virus
Fungus
Parasites

Question 3

Host Defenses

Answer 3

1. Skin barrier
2. Biological - normal flora
3. Chemical - pH

Question 4

Routes for spread of infection

Answer 4

blood
lumph
tissue planes

Question 5

Types of damage

Answer 5

Localized
Widespread
Invasive

Question 6

Localized Damage

Answer 6

occurs at the site of injury and may spread to surrounding tissue
Damage is related o intensity of inflammatory response
- bacteria is usually more localized than virus or parasite

Question 7

Widespread Damage

Answer 7

release of endotoxins causes damage at the site of entry and a distance from entry point
Degree of spread depends on pathogen, condition of host, entry site
Viruses take over host cell function –> widespread

Question 8

Invasive Damage

Answer 8

cellular alterations occur
Loss of host cell function
Viral or parasitic

Question 9

Factors that inc risk of infection

Answer 9

Impaired nutritional status
Dehydration
Age
Renal and Hepatic dysfunction
Immune sys function
Vascular condition of host tissue
Poor sanitation

Question 10

Impaired nutritional status

Answer 10

Dec macrophage func
T lymph func is depressed
Antibody production is less sens
Overall not a good inflammatory response

Question 11

Dehydration

Answer 11

Inc core temo
changes in HR responses
Changes in resp

Question 12

Age

Answer 12

Dec in function of mechanical barriers

Inc risk of pathologies that alter biological and chemical barriers

Question 13

Metabolic cost of infection

Answer 13

inc basal metabolic rate and energy consumption

Question 14

Fever - Metabolic consequence

Answer 14

Ant hyp is sens to endogenous pyrogens –> these are released by cells involved in host defense –> thought to have pos effect on course of infection

Question 15

For every 1 degree celcius rise in temp…

Answer 15

there is a 13% inc in the BMR

Question 16

Low and high grade fever

Answer 16

Low = >98.6 to 102
High = > 102

Question 17

Fever and PT

Answer 17

Dont work with patients who hace a high grade temp - functional things ok

Question 18

Metabolic consequence - protein metabolism

Answer 18

inc with fever
body needs the proteins to fight infection
normal mechanisms for energy are inhibited with acute infections

Question 19

Metabolic consequences - mineral metabolism and acid/base balance

Answer 19

Initially NA and H20 retention occur - not peeing
Then during convalescent phase diuresis occurs
Acid/base imbalance may occur - not problem if hsort course but can become issure if infection is severe or prolonged

Question 20

Metabolic consequence - immune system

Answer 20

lymphocytes - inc # of them

Question 21

Metabolic consequence - hematologic system

Answer 21

Inc CO demand (inc BMR)

Severe acute infection and in chronic there will be bone marrow effects –> dec RBCs and Inc WBCs

Question 22

course of infection is dependent on

Answer 22

pathogen and condition of the host

Question 23

Chronic infections

Answer 23

initial stages are the same as acute
s/s wax and wane
No quick resoluation
Hep is Ex

Question 24

Latent Infections

Answer 24

s/s subside as they do in acute infections but reappear again later
Chicken pox –> shingles

Question 25

Secondary acute infection

Answer 25

follow primary infections that have left the host susceptible - allows for pathogen entryway

Question 26

Subclinical infection

Answer 26

does not reach prodromal stage Pathogens have colonized though Can be transmitted

Question 27

Bacteremia

Answer 27

Transient presence of pathogens in the blood as result of localized infection Tends to not produce s/s

Question 28

SIRS

Answer 28

Systemic Inflammatory Response Syndrome Systemic inflammatory response to a wide variety of severe clinical insults manifests by 2 or more of following conditions:

Question 29

Conditions for SIRS

Answer 29

Temp higher than 100.4 or less than 96.8 HR higher than 90 RR higher than 20 or PaCO2 less than 32 WBC higher than 12000 or less than 4000

Question 30

Septicemia

Answer 30

Repid multiplication of and prolonged presence of pathogens within the blood Significant s/s may be present

Question 31

CLinical features of septicemia

Answer 31

Headaches, lethargy, apprehension, fever, hypotension, rigors, petechial hemorrhages

Question 32

Septic Shock

Answer 32

Circulatory failure with inadequate tissue perfusion | Sever infection can lead to septicemia which will trigger a systemic inflammatory cascade leading to septic shock

Question 33

Hemodynamic changes with septic shock

Answer 33

 Low systemic vascular resistance  Low central venous pressure and pulmonary artery occlusion pressure  CO is high  Myocardial depression with low ejection fraction  SV is maintained by ventricular dilation and CO is inc by tachycardia

Question 34

Clinical s/s septic shock

Answer 34

```  Fever  Nausea, vomiting  VD  Bounding pulse  Hypotensive  Coagulopathies  Coma  Jaundice ```

Question 35

Tests and Measures for Dx of infection

Answer 35

Physical exam - vitals, skin rashes, lymphadenopathy, hepatosplenomegaly CBC, Urinalysis, chest x-ray, blood culture

Question 36

Bactericidal drugs

Answer 36

destroy pathogen

Question 37

Bacteriostatic drugs

Answer 37

inhibit growth

Question 38

Blind (wide spectrum) therapy

Answer 38

havent done analysis of what pathogen is

Question 39

Penicillan

Answer 39

active agents effect the wall of bacteria can be cidal or static about 15% of pop is allergic

Question 40

Cephalosporin

Answer 40

broader rang of action than Pen Inhibit cell wall synthesis nephrotoxicity can be problem

Question 41

Sulphoamide

Answer 41

bacteriostatic inhibits microbial folic acid synthesis allergies

Question 42

Tetracycline

Answer 42

``` inhibits protein syn limited use resistance develops used secondary to pen allergy effects bones and teeth ```

Question 43

Erythromicin

Answer 43

inhibits protein synth bacteriostatic similar to pen used mainly in resp, skin, and GU infections

Question 44

MRSA

Answer 44

is a gram positive cocci  A healthcare associated infection  healthcare environment puts pt at risk od MRSA  Highly resistant  Primary antibiotic used to treat is vancomycin  Can produce septic shock and is highly transmittable

Question 45

VRE

Answer 45

 Enterococci are part of the normal GI flora  Common infections include skin, urinary tract, meningitis, endocarditis, bacteremia  Healthcare associated infection