Week 11 Obstructive Disease

Question 1

what are the three main causes of dyspnea?

Answer 1

ventilatory pump - hypoxic hypoxia (hypoxemia): not enough oxygen in the blood; carbon dioxide build up
cardiac pump/supply lines - ischemic hypoxia (ischemia): heart is not getting enough blood
blood’s oxygen carrying capacity-anemic hypoxia (anemia)

Question 2

what is restrictive disease?

Answer 2

difficulty in generating the △P required to create airflow (inhaling)

Question 3

what is obstructive disease?

Answer 3

difficulty in generating airflow for a given △P between the atmosphere and alveoli (exhaling)

Question 4

in restrictive disease, what is stiffness caused by? weakness?

Answer 4

stiffness - chest wall or lungs
weakness - weak muscles and damaged nerves

Question 5

what spirometry volumes are reduced in restrictive disease?

Answer 5

all

Question 6

what characterizes obstructive disease?

Answer 6

increased FRC, marked increase in A-P diameter (barrel0chested), and slow expiration

Question 7

what are the two basic causes of obstructive disease?

Answer 7

-increased airway resistance
-decreased elastic recoil; diminished ability to expire has same consequences as physical obstruction

Question 8

what is the equal pressure point?

Answer 8

point in airway anatomy where outside compressive pressure equals inside elastic pressure

Question 9

where should equal pressure point occur?

Answer 9

in the larger airways with cartilaginous rings; if it occurs in the smaller airways they will collapse during forced expiration

Question 10

what are the four main obstructive diseases?

Answer 10

asthma, bronchiectasis, chronic bronchitis, emphysema

Question 11

Identify each type of hypoxemia described below:
-SOB with normal sPO2 and PO2, normal blood flow, and inadequate O2 carrying capacity
-SOB with normal sPO2 and Po2, normal O2 carrying capacity and inadequate blood flow
-SOM with decreased sPO2 and PO2, normal blood flow and normal O2 carrying capacity

Answer 11

-anemic hypoxemia
-ischemic hypoxemia
-hypoxic hypoxemia

Question 12

what is emphysema?

Answer 12

abnormal, permanent enlargement of air spaces distal to bronchioles with destruction of their walls.
decreases elasticity and increased compliance in alveolar walls

Question 13

what are the signs and symptoms of emphysema?

Answer 13

barrel chest, emaciated, hypertrophied SCM and scalene, prolonged expiration, tripod position and pursed lip breathing, FEV1/FVC ratio <.60, classic appearance of “pink puffer”

Question 14

what can emphysema progress to?

Answer 14

cyanosis
cor pulmonale (right sided heart failure)
LHF

Question 15

what medical and surgical management is used for emphysema?

Answer 15

bronchodilators
supplemental O2
lung reduction surgery
(airway clearance is not specifically needed for pure emphysema)

Question 16

what is chronic bronchitis?

Answer 16

excessive sputum production on most days for at least 3 months of the year for at least 2 consecutive years
impaired mucus clearance

Question 17

what is chronic bronchitis associated with?

Answer 17

cigarette smoking, air pollution, infections (hemophilus, strep pneumonia)

Question 18

what is the progression of chronic cronchitis?

Answer 18

• Smoking predisposes to infection
• Decreased ciliary clearance
• Damaged epithelium
• Interference with WBC function
• Irritation of airways
• Hyperplasia of mucus glands in
  large airways
• Excessive mucus production

Question 19

what is “blue bloater”?

Answer 19

overweight and cyanotic
hypercapnic
cor pulmonale –> LHF

Question 20

what does medical management of chronic bronchitis consist of?

Answer 20

bronchodilators, supplemental O2, antibiotics, airway clearance

Question 21

what is bronchiectasis?

Answer 21

chronic and permanent dilation of bronchi due to inflammation or infection
copious amounts of foul-smelling sputum, dilated obliterated bronchi, mucus plugging of bronchi

Question 22

what are the signs and symptoms of bronchiectasis?

Answer 22

chronic coughing, coughing up blood, abnormal sounds of wheezing in the chest on breathing, SOB, chest pain, coughing up large amounts of mucus, daily bad breath odor, skin with blue appearance, weight loss, fatigue, thickening of the skin under nails and toes

Question 23

what are the causes of bronchiectasis?

Answer 23

idiopathic, obstruction by tumor or foreign object, immotile cilia, congenital, post-infective/cystic fibrosis

Question 24

what medical/surgical management is used for bronchietasis?

Answer 24

antibiotics, airway clearance, surgical removal of affected areas

Question 25

which of the following is described as inflammation of the bronchial walls without an increase or change in bronchial wall diameter?

Answer 25

bronchitis: no change in the wall diameter, the inflammation narrows the airways (bronchiectasis: wall are dilated and eventually are destroyed; emphysema: mainly the alveoli are affected)

Question 26

what is the normal mechanism for control of ventilation?

Answer 26

primary is negative feedback loop between pH of CSF and ventilation secondary include negative feed back loop between arterial PO2 and pH and feedforward mechanisms

Question 27

what happens in response to decreased pH?

Answer 27

ventilation increases volatile acid (Co2) is lost to atmosphere pH is normalized chronically, kidneys and buffering systems respond to eliminate fixed acid

Question 28

what happens in response to increased pH?

Answer 28

ventilation is slowed Co2 accumulates pH is normalized chronically kidneys and buffering systems respond to retain hydrogen ions and excrete more bicarbonate

Question 29

___ results in decreased PaCO2. ___ results in increased PaCO2.

Answer 29

hyperventilation hypoventilation

Question 30

how does high CO2 effect the brain?

Answer 30

depresses cerebral function (giddy-somnolent-unconscious-dead) cerebral blood flow rids brain of CO2 by negative feedback loop (high CO2-increased blood flow-normalized CO2)

Question 31

how does low CO2 effect the brain?

Answer 31

(hyperventilation) decreased cerebral blood flow compromises cerebral function lightheaded, dizzy, ataxic, other

Question 32

how is FIO2 increased when using supplemental O2?

Answer 32

by increasing flow rate or increasing % O2

Question 33

what is FIO2 of normal air?

Answer 33

.21 21% O2

Question 34

if low PaO2 is driving ventilation, excessive FIO2 causes:

Answer 34

breathing to slow (hypoventilation) allowing PaO2 to fall to regulated level hypoventilation = accumulation of CO2 CO2 retention causes respiratory acidosis, possible injury

Question 35

Effective ventilation requires:

Answer 35

bulk flow of air in and out of lungs to get oxygen to a place where it could enter the blood diffusion of gases across the alveoli into the pulmonary capillary blood

Question 36

High ventilation makes alveoli like the atmosphere: ___ low ventilation makes alveoli like venous blood: ___

Answer 36

atmosphere: high PO2 and low PCO2 venous blood: low PO2 and high PCO2

Question 37

what is the V/Q ration?

Answer 37

the primary determinant of oxygenation of the blood optimal V/Q = 0.8

Question 38

what occurs when increasing V/Q? decreasing V/Q?

Answer 38

increasing V/Q increases PaO2 and lowers PaCO2 decreasing V/Q decreases PaO2 and increases PaCO2

Question 39

low ventilation relative to perfusion results in:

Answer 39

low PaO2 and unloaded Hb leaving the alveolar capillaries hypoxic hypoxia; PCO2 rises causing acidosis

Question 40

high ventilation relative to perfusion causes:

Answer 40

PO2 to rise and PCO2 to fall

Question 41

ventilation increases in proportion to:

Answer 41

pulmonary blood flow

Question 42

what occurs as V/Q exceeds 0.8?

Answer 42

PO2 increases, but oxygen content of blood changes little wasted ventilation more oxygen is used by muscles of ventilation than what is added by increasing V/Q above 0.8 (less oxygen is available for the rest of the body)

Question 43

if cardiac output is low and V/Q is normal (or high):

Answer 43

PaO2 may be high result at tissue level is ischemic hypoxic and cellular injury

Question 44

if cardiac output is normal and V/C is low:

Answer 44

PaO2 becomes low results in hypoxic hypoxia and cellular injury

Question 45

FEV1/FVC determines __.

Answer 45

extent of obstructive disease

Question 46

what is included in a lung volumes test?

Answer 46

tidal volume, IRV, ERV, VC (require He or N2 washout) RV, TLV and FRC

Question 47

low volumes/ peaked slopes = ___ scooped out (slow decrease in volume) = ___

Answer 47

restrictive disease obstructive disease

Question 48

What does DLCO measure?

Answer 48

the ability of the lungs to transfer gas from inhaled air to the red blood cells in the pulmonary capillaries diffusion barrier at alveolar-capillary interface

Question 49

diffusion is decreased by:

Answer 49

anemia increased diffusion distance decreased exchange area poor perfusion

Question 50

oxygenation of tissues requires ___.

Answer 50

cardiac output - low CO is great for oxygenating blood, bad for the body