Test 4 Flashcards
(162 cards)
1
Q
FRC:
2 primary physiologic functions
A
- determines point for resting ventilation
- determines O2 reserve
2
Q
can this lung volume measurement to detect small airway diseases before symptoms appear
A
closing volume
3
Q
sum of closing volume and residual volume
A
closing capacity
4
Q
volume of gas in excess of RV at time when small airways in the dependent portions of the lungs close during maximal exhalation
-measured by breath nitrogen washout test
A
closing volume
5
Q
volume below which small airways begin to close during expiration
A
closing volume
6
Q
normal FEV 25-75% for healthy 70 kg male
A
4.7 L/sec
7
Q
what does Maximum voluntary ventilation (MVV) measure
A
endurance of ventilatory muscles
-indirectly reflects lung thoracic compliance & airway resistance
8
Q
best ventilatory endurance test
A
MVV
9
Q
avg MVV in young healthy adult
A
170 L/min
lower in females
dec with age (both sexes)
10
Q
Collectively measures all factors that affect diffusion of gas across alveolar-capillary membrane
A
Carbon monoxide diffusion capacity
11
Q
CO affinity for Hg in comparison to O2
A
CO 200x more affinity for Hg than O2
12
Q
partial pressure of carbon monoxide in blood
A
nearly zero
13
Q
DLCO is recorded in _______ @ STPD
A
DLCO is recorded in ml of CO/min/mmHg @ STPD
14
Q
Person with normal hgb and V ̇/Q ̇ - main factor limiting diffusion is _____ _____ ______.
A
Person with normal hgb & V ̇/Q ̇ - main factor limiting diffusion is alveolar-capillary membrane
15
Q
CO diffusion capacity: Avg value resting subjects single-breath method is ____ml CO/min/mm
A
CO diffusion capacity: Ave value resting subjects single-breath method is 25ml CO/min/mm
inc 2-3x w/ exercise
16
Q
CO diffusion capacity
Influencing Factors:
A
- Hgb (direct relationship)
- alveolar pco2 (direct)
- supine position (inc DC)
- pulmonary capillary blood volume
17
Q
CO Diffusing Cap:↓ in alveolar fibrosis asso with:
A
CO Diffusing Cap: ↓ in alveolar fibrosis asso with:
- sarcoidosis
- asbestosis
- berylliosis
- oxygen toxicity
- pulmonary edema
18
Q
CO Diffusing Cap
↓ in COPD due to what 4 thing:
A
CO Diffusing Cap
↓ in COPD due to
- V ̇/Q ̇ mismatch
- ↓ alveolar surface area
- loss of capillary bed
- ↑ distance from terminal bronchiole to alveolar-capillary bed
19
Q
chronic allergic type lung response that is caused by exposure to berilium and its compounds. occuptionalhazard in the 1950s, treatable but not curable
A
berylliosis
20
Q
measurement of pulmonary volume over time
A
spirometry
21
Q
exams performed to evaluate lung volumes along with inspiratory & expiratory flow of gas
Many of these measurements are derived from having patient breathe through a closed circuit with measurement of gas flow & composition
A
PFT
22
Q
Change in absolute volume of IC parallels change in __.
A
VC
23
Q
Balance of inward (lung) forces with & outward (chest wall) forces
A
FRC
24
Q
2 primary functions of FRC
A
1) Determines point for resting ventilation
2) Determines oxygen reserve
25
2 reasons FRC important
1) Inflating an opened lung is easier than inflating deflated lung
2) Prevents major desaturation after exhalation
26
Factors affecting FRC
1) Body habitus
2) Sex
3) Posture
4) Lung disease
5) Diaphragmatic tone
27
Total amount of new air into respiratory passages each minute
Equal to TV x RR
Averages 6 L/min
Minute Resp Volume
28
Volume of gas in the lungs in excess of RV at the time when small airways in the depended portions of the lungs close during maximal exhalation, measured by:
single breath nitrogen washout test
29
FVC: Values ____ ml/kg associated with ↑ incidence of postoperative pulmonary complications (PPCs) – poor cough
FRC: Values **\< 15 ml/kg** associated with ↑ incidence of postoperative pulmonary complications (PPCs) – poor cough
30
Most important is its comparison to patient’s FVC
Forced Expiratory Volume (FEVT)
Normally can expire ¾ of FVC in 1st sec
31
most commonly reported PFT
Normal values
FEV1
Normal value **≥ 75%** FVC (**FEV1/FVC ≥ 0.75**)
1. **0.5 sec - expire 50-60 %**
2. **1 sec - 75-80%**
3. **2 sec - 94%**
4. **3 sec - 97% (volume is @ least 80% of VC)**
32
FEV1
Validity highly dependent on __ & \_\_
FEV1
Validity highly dependent on **cooperation & effort**
33
Ave forced expiratory flow during middle half of FEV
(what test is this)
FEF 25-75%
34
FEF 25-75% test
aka
maximum mid-expiratory flow rate
35
FEF 25-75% test
Normal value is\_\_\_ % of predicted
more reliable and reproducible than what PFT
FEF 25-75% test
Normal value is **100 ± 25 %** of predicted
\> Reliable & reproducible than **FEV1/FVC**
36
what test is this
* Largest volume of gas that can be breathed in 1 min voluntarily
* Breathe deeply & rapidly as possible for 10, 12, or 15 sec
* Results are extrapolated to 1 min
* Subject sets rate & moves \> VT but \< VC
* Measures endurance of ventilatory muscles
* Indirectly reflects lung-thorax compliance & airway resistance
Maximum Voluntary Ventilation (MVV)
37
Flow generated during forced expiratory maneuver followed by forced inspiratory maneuver
Plotted against volume of gas expired
flow volume loop
38
flow volume loop:
## Footnote
\_\_\_\_\_ of loop most informative part
FVL
**Configuration** of loop most informative part
39
**Flow volume loops**
Zero point on x-axis is ___ \_\_\_\_\_\_
Lungs cannot empty due to \_\_
**Flow volume loops**
Zero point on x-axis is **full inspiration**
Lungs cannot empty due to **RV**
40
Flow volume loops
Most important part is **\_\_\_\_ flow (insp or exp)**
Flow volume loops
Most important part is **expiratory flow**
Volume begins@ this point
Ends when loop reaches x-axis again
41
Flow volume loops:
Obstructive disease characterized by:
Flow volume loops:
Obstructive disease characterized by:
1. **reduced peak flow rates**
2. **sloping of expiratory limb**
42
Flow volume loops:
**Restrictive** disease characterized by:
Flow volume loops:
**Restrictive** disease characterized by:
1. **normal or heightened peak expiratory flows**
2. **very narrow loop (reduced VC)**
43
which type of restrictive disease?
Abnormal movement of intravascular fluid into interstitium & alveoli
Due to ↑ PVR from LVF, fluid overload, or ↑ pulm cap permeability
EX: pulmonary edema, aspiration pneumonia, & ARDS
acute intrinsic
44
which type of restrictive disease?
Diseases with pulmonary fibrosis
EX: IPF, radiation injury, cytotoxic and noncytotoxic drug exposute, oxygen toxicity, autoimmune disorders, sarcoidosis
chronic intrinsic
45
which type of restrictive disease?
## Footnote
Disorders that inhibit lung expansion
EX: flail chest, pneumothorax, pleural effusions,
Limit chest-expansion: ascites, obesity, pregnancy, skeletal & neuromuscular disorders
chronic extrinsic
46
Supine position ↓ FRC __ % in healthy person
worse in sick pt
GA decreases this further by
Supine position **↓ FRC 10-15%**
## Footnote
**GA another 5-10%**
47
ventilator settings (tv and RR)
reduce risk of barotrauma
lower TV
inc RR
48
FRC restores after ___ hrs postop
FRC restores after **12 hr** postop
49
**American Thoracic Society & European Respiratory Society** “’preventable and treatable disease state characterized by airflow limitation that is not fully reversible. The airflow limitation is usually progressive and is associated with an abnormal inflammatory response of the lungs to noxious particles or gases…” defines what disease
Obstructive Pulmonary Disease
50
Which obstructive disease:
## Footnote
Destruction of parenchyma leading to loss of surface area, elastic recoil & structural support
**Emphysem'er**
51
Which obstructive disease:
## Footnote
Narrowing of small airways by inflammation and mucous production
**Chronic bronchitis**
52
Which obstructive disease?
* Numerous chronic conditions
* Not mutually exclusive
* May precede emphysema & chronic bronchitis
**Peripheral airways disease**
53
dominant clinical feature of obstructive disease
impaired **expiratory** airflow
54
condition of the lung characterized by abnormal permanent enlargement of the air spaces distal to the terminal bronchiole, accompanied by destruction of their walls and **without obvious fibrosis**
**emphysema**
Changes are irreversible
55
subclass of ephysema: 2 with definitions
* **Centrilobular:** dilation affects respiratory bronchioles upper lobes
* **Panlobular:** tissue destruction is widespread, involves acinus (16-17th gen)
56
4 primary alterations in pulmonary function of emphysema
4 primary alterations in pulmonary function
* **↑ in size acini**
* **Consolidation of alveoli**
* **V/Q mismatch**
* **Loss of alveolar walls**
57
What obstructive disease?
Chronic or recurring excess mucous secretion on most days for at least 3 months of the year for at least 2 successive years
Critical element: airway obstruction of expiratory airflow
**Chronic bronchitis**
58
What obstructive disease?
## Footnote
Inflammation of all terminal & respiratory bronchioles, fibrosis, narrowing of airway walls, & goblet cell metaplasia
EX: **sarcoidosis, Wegener granulomatosis, mineral dust-associated airways disease, disease from exposure to fumes and toxins, and bronchocentric granulomatosis**
**Peripheral airway disease**
59
now list tell me about peripheral airway disease?
characteristics:
**Peripheral airway disease:**
* Inflammation of all terminal & respiratory bronchioles, fibrosis, narrowing of airway walls, & goblet cell metaplasia
60
now tell me more about peripheral airway disease?
give examples:
* **sarcoidosis**
* **Wegener granulomatosis**
* **mineral dust-associated airways disease**
* **disease from exposure to fumes and toxins**
* **bronchocentric granulomatosis**
61
Principal factor for development of COPD
**smoking**
environmental effects - minimal
some due to imbalance btw protease vs antiprotease activity
62
Dominant feature: COPD
why is FEV1 reduced?
**Progressive airflow obstruction**
**↓ FEV1**
* 1) decrease of **intrinsic** size of bronchial lumen
* 2) increase in collapsibility of bronchial walls
* 3) decrease in elastic recoil of lungs
63
COPD: Airway narrowing primarily due to:
COPD: Airway narrowing primarily due to **thickening of airway walls**
## Footnote
**(not due to inc muscle tone like in asthma)**
64
Major difference btw asthma and COPd:
Airway hyperreactivity affects which airways segments primarily in COPD:
**Airway hyperreactivity** affects **small airways** more than large (in **COPD**)
65
COPD: single best variable for predicting airflow obstruction? (related to smoking)
**patient smokes 40 pack per year (PPY)**
66
highly indicative (almost gauranteed) of severe COPD of airflow and dx of COPD.
Related to smoking
**Patient smokes 50 PPY**
**current wheezing**
67
hallmark of obstructive disease
**reduction of FEV1**
(can also indicate restrictive disease - reduced FEV1 but **ratio is norma**l)
68
FEV1/FVC % indicates COPD
FEV1 % = mild
FEV1 % = moderate
FEV1 % = severe
FEV1 % = very severe
FEV1/FVC **\< 0.7** indicates **COPD**
* FEV1 **\> 80%** = **mild**
* FEV1 **50-79%** = **moderate**
* FEV1 **30-49%** = **severe**
* FEV1 **\< 30%** = **very severe**
69
goals of vent mngt in obstructive diz (5)
* vadequate **oxygenation**
* eliminate **CO2**
* avoid **barotrauma**
* avoid tissue **injury** from repeated airway opening and closure
* avoid **volutrauma**
70
Obstructive dz:
Oxygenation is managed with what firstly:
**Oxygenation** is managed with **FIO2**
but **avoid** absorptive atelectasis from too much fiO2!
71
pure memorization question:
Patients with marked obstructive pulmonary disease are at increased risk for both ___ and \_\_.
Patients with marked obstructive pulmonary disease are at increased risk for both **intraoperative** and **PPCs**
72
Management obstructive dz:
Preop FEV1 ____ correlates with ↑ in ___ during GA
Management obstructive dz:
**Preop FEV1 reduction** correlates with **↑ in CO2** during GA
73
ETT issues related with COPD: (3)
1. **inc airway resistance**
2. **reflex bronchoconstriction**
3. **limits ability to clear secretions**
74
indication for possibly doing ABG on obstructive dz
1. **arterial hypoxemia**
2. **severe enough COPD**
3. **CO2 retention**
4. **currently on O2**
5. **struggling to breathe**
75
contraction of diaphragm causes these several changes (lungs, abd contents, ribs, chest)
* Pulls lower surfaces of the lung down
* Abdominal contents move downward and forward
* Lower ribs rise; chest widens
76
accessory muscles of inspiration (4)
* Internal Intercostals (parasternal portion)
* Sternocleidomastoid – Lifts sternum
* Scaleni – Lifts 1st 2 ribs
* Anterior serrati
77
Most important muscles that elevate the chest cage
Increase A-P diameter of chest by 20%
external intercostals
78
Pleural pressure:
Slightly negative pressure ~ -5cm of H2O @ begin of inspiration due to what?
Pleural pressure:
Slightly negative pressure ~ -5cm of H2O @ begin of inspiration due to **opposition of lung tissue contraction & chest wall expansion**
79
by convention we use this pressure as a measure of intrathoracic pressure
**pleural pressure**
**intrapleural pressure**
(same thing)
80
Difference between that in alveoli & outer surfaces of the lungs (outer surface = pleural pressure)
**TPP**
81
what is transpulmonary pressure the difference of?
TPP
**alveolar press - intrapleural press** (outer surface of lungs or pl pressure)
82
Chest and lungs elastic properties
Chest & lungs have elastic properties
* Chest expands outward
* Lungs collapse
83
2 Elastic forces of lung tissue
Elastic forces of lung tissue
## Footnote
**Elastin**
**Collagen**
84
Elastic forces caused by what tension?
Elastic forces caused by **surface tension**
85
alveolar collapse is directly proportional to
**alveolar collapse** is directly proportional to **surface tension**
86
Formula for surface tension related to law of laplace
**(P = 2T/r)**
**or**
**Pressure = 2 x Surface tension/radius**
87
definition of lung compliance
Lung Compliance
Definition: **change in volume divided by the change in pressure (V/P)**
**C = ∆V/∆P**
88
Extent lungs will expand for each unit ↑ in transpulmonary pressure
**Total compliance of both lungs normal adult ≈ 200 ml/cm H2O transpulmonary press.**
OR
**When transpulmonary press ↑ 1cm H2O, lung volume expand 200 ml after 10-20 sec**
89
lung compliance formula
and normal value
CL = Change in **lung volume**/change in **TPP**
≈ **150-200 mL/cm H2O**
90
chest wall compliance formula
and normal value
CW = change in **chest volume**/change in **TTP**
Where transthoracic pressure =
atmospheric pressure – pleural pressure
≈ **200 mL/cm H2O**
91
92
* Describes pressure-volume relationship for lung when air is not moving
* Reflects compliance of lung & chest wall alone
* ↓ by conditions that make the lung abnormally stiff or difficult to inflate
* ↑ by emphysema which destroys elastic tissue of lung
**static effective compliance**
93
static effective compliance
↓'d by conditions that make the lung abnormally stiff or difficult to inflate
**what are some examples of these conditions?**
* fibrosis
* obesity
* vascular engorgement
* edema
* ARDS
* external compression of chest
94
* Compliance of lung while air is moving
* Affected by same factors as static compliance plus airway resistance
* and .. how is it calculated?
**dynamic compliance**
**TV/(PIP – PEEP)**
95
Opposes inflation of lungs
(besides static elastic recoil, there are 2 more factors)
Opposes inflation of lungs
1. **Frictional resistance of lung tissues**
2. **Resistance to airflow**
96
**Resistance** is _\_\_\_\_\_\__ proportional to **gas density**
**Resistance** is _\_\_\_\_\_\__ proportional to **5th power of the radius**
**Resistance** is _directly_ proportional to **gas density**
**Resistance** is _inversely_ proportional to **5th power of the radius**
97
**\_\_\_ number** is predictive of turbulent or laminar airflow
what is the formula?
**Reynold’s number** is predictive of turbulent or laminar airflow
## Footnote
**Re = ρνd/η**
98
**Re = ρνd/η**
what do all those mean?
* **Re** is Reynold’s number
* **ρ** is density of the fluid
* **ν** is velocity of fluid flow
* **d** is diameter of the vessel
* **η** is viscosity of the fluid
or
**Re = (linear velocity x diameter x gas density)/**
**gas viscosity**
99
Low Re **\_**_amnt_**?\_** (Nagelhout) – **_(lam or turb)_**
High Re**\_**_amnt_**?\_** (Nagelhout) - **_(lam or turb)_**
what is the range for transitional area for resistance?
Low Re **\< 2000** (Nagelhout) – **laminar**
High Re **\> 4000** (Nagelhout) - **turbulent**
**Transitional Area of Resistance (2000-4000)**
100
True laminar flow occurs in **\_\_\_** airways
Turbulence found in **\_\_\_\_** airways
(answer in size)
True laminar flow occurs in **smaller** airways
Turbulence found in **larger** airways
101
40% of total airway resistance in **\_\_\_** airways?
40% of total airway resistance in **upper** airways
(nasal cavity, pharynx, larynx)
102
Greatest resistance to airflow in **\_\_\_\_**-sized bronchi
(small, medium, large)?
Greatest resistance to airflow in **medium**-sized bronchi
103
1. work needed to expand lungs against elastic forces of ulngs and chest
2. work needed to overcome the viscocity of lung and chest wall
3. work needed to overcome AW resistance to movement of air into lungs
1. **compliance work =** work needed to expand lungs against elastic forces of ulngs and chest
2. **Tissue "frictional//resistance" work =** work needed to overcome the viscocity of lung and chest wall
3. **"Frictional" AW resistance work =** work needed to overcome AW resistance to movement of air into lungs
104
**Compliance work**
**Tissue "frictional//resistance" work**
**"Frictional" AW resistance work**
(see what i did there... :) what are the definitions bc ur gonna have to memorize word for word.
**compliance work** = work needed to expand lungs against elastic forces of lungs and chest
**Tissue "frictional//resistance" work** = work needed to overcome the viscocity of lung and chest wall
**"Frictional" AW resistance work** = work needed to overcome AW resistance to movement of air into lungs
105
Respiratory muscles use **\_\_\_%** of total body energy normal quiet breathing
what is the increase during exercise?
Respiratory muscles use **3-5%** of total body energy
normal quiet breathing
**inc 50-fold with exercise**
106
respiratory changes with aging
**Dilation of alveoli**
**↓ lung recoil (reduce elastin/collagen)**
**↓ chest wall compliance → ↑ work of breathing**
**Respiratory muscle strength decreases**
**Expiratory flow rates decrease**
**Respiratory centers in nervous system show ↓ sensitivity to hypoxemia & hypercapnia**
107
reduced FRC due to alveolar collapse & compression causes these 3 changes:
1. **Loss of inspiratory tone**
2. **Change in chest wall rigidity**
3. **Upward shift of diaphragm**
108
Supine position ↓ FRC ____ L
Induction of GA ↓ FRC by another ____ L
**Supine** position ↓ FRC **0.8-1.0 L**
**Induction** of GA ↓ FRC by another **0.4-0.5 L**
109
**FRC and closing capacity reduced to same extent under GA**
Risk of **shunting** greatest in these patients: (list 3)
Risk of shunting greatest in:
1. **elderly**
2. **obese**
3. **pulmonary disease**
110
Effects of Anesthesia on **Resistance**
* **Increased if obstruction** (tongue, laryngospasm)
* Bronchoconstriction – if **light anesthesia**
* **Secretions or blood** in airway
* **Equipment** – ETT, connectors, malfunction of valves
* Increases not seen due to bronchodilating properties of volatile agents
111
Age dependent formula/estimate for PO2 (A-a gradient)
**0.21 x (Age + 2.5)**
\*room air, adjust to FiO2 as needed\*
112
Normal A-a gradient
\<10-15 mm Hg
113
Work of Breathing
Increased by:
Work of Breathing
Increased by:
* **Reduced lung & chest wall compliance**
* **Rarely by airway resistance**
Effects usually overcome by controlled mechanical ventilation
114
PIO2 is reduced from ____ to _____ as it enters the alveoli
160 mm Hg to 149 mm Hg
115
PAO2 formula?
PAO2= FiO2 x (PB-PH20) - (PaCO2/RQ)
0.21 x (760-47) - (PaCO2/RQ)
116
Large increases in arterial CO2 (\>75) will produce \_\_\_\_\_\_\_\_
Hypoxia (arterial O2 \<60) if patient is on RA; supplement with FiO2 to prevent this
117
How to estimate PAO2?
FiO2 x 6
118
The decrease in PaO2 (O2 tension) as the body ages is due to what factor?
Progressive increase in closing capacity relative to FRC
119
The most common mechanism for hypoxemia is?
Increased A-a gradient
120
A-a gradient for O2 depends on 3 things:
1. amount of R to L shunt (directly proportional)
2. amount of VQ scatter
3. mixed venous O2 tension (indirectly proportional)
121
The tracheobronchial tree has an increase in total _______ pathways and total _______ \_\_\_\_\_\_\_ areas with each successive generation toward the periphery.
Parallel
cross sectional
122
Airflow velocity is increased/decreased at the lower generations of the tracheobronchial tree.
Decreased compared to the upper airways.
Velocity d/c from the trachea to peripheral distal airways.
123
Airflow at convective airways is mostly \_\_\_\_\_\_\_
laminar
124
At what level of bronchioles does diffusion begin?
Terminal bronchioles (**16th generation)**; diffusion is primary mode of transport and occurs b/c of kinetic motion of molecules in the respiratory gases
125
Hypercapnia is NEVER due to what?
Defective diffusion
CO2 is 20X more diffusible than O2 and thus hypercapnia is related to inadequate alveolar ventilation and not diffusion.
126
Whose law allows us to calculate partial pressures of gases?
Henry's Law
127
Solubility of O2, CO2, and Nitrogen?
O2 0.024
CO2 0.57
Nitrogen 0.012
128
Vapor pressure depends entirely on \_\_\_\_\_\_\_?
Temperature
129
With normal alveolar ventilation, 1/2 of alveolar air is removed in __________ seconds?
17
130
Benefits of slow exchange of alveolar and atmospheric air?
1. Prevents rapid change of gas concentration in blood
2. Prevents excessive increase and decrese in tissue oxygenation
- tissue CO2 concentration
- tissue pH during apneic periods
131
Which two factors determine the diffusion coefficient of a gas?
Solubility
Molecular Weight
132
Diffusion coefficients for respiratory gases?
O2 1
CO2 20.3
CO 0.81
N 0.53
Helium 0.95
133
Alveolar capillary membrane layers from inside alveolus to capillary?
1. fluid and surfactant layer
2. alveolar epithelium
3. epithelial basement membrane
4 interstitial space
5. capillary basement membrane
6. capillary endothelium
134
Average diameter of pulmonary capillary?
5-10 micrometers
135
Mean pulmonary transit time
4-5 seconds
136
How much time does blood spend in pulmonary capillary?
0.75 seconds
With exercise and increased CO, this can be reduced to 0.25 sec.
137
How much time does it it take before a RBC is saturated w/ O2 in a pulmonary capillary?
0.25 seconds
This is also the time that equilibriation occurs b/w alveolar air and capillary blood.
138
During exercise the reduced circulatory time has a greater effect on O2 or CO2?
O2 because CO2 diffuses 20x faster than O2
139
Normal O2 absorption rate
250 mL/min
Increases up to 1000mL/min during moderate exercise
140
Normal alveolar ventilation rate
4.2 L/min
Increases by 4x during exercise
141
What is the max PO2 of humidified air?
149 mmHg
142
Solubility coefficient of O2 in plasma?
0.003
so 0.003 mL of O2/1 mmHg partial pressure of PO2 in 100 mL of plasma
143
What is arterial blood PO2?
95 mm Hg
144
What is interstitial fluid PO2?
40 mm Hg
\*same as venous blood PO2\*
145
What is the range for intracellular PO2?
5-40 mmHg
23 is the average
146
How much O2 in mmHg is required for full support of chemical processes in the cells?
1-3 mm Hg
\*So PO2 of 23 mm Hg which is average is more than enough\*
147
What pressure gradient is required for CO2 to diffuse from tissues to capillaries and from capillaries to alveoli?
5 mmHg
148
An average of ___ mL of CO2 is transported from tissues to lungs per 100 mL of blood?
4 mL
149
Carbonic anhydrase catalyzes what reaction? Accelerates it by how much?
Catalyzes CO2 and H20 to form carbonic acid
Accelerates it by 5000x so that equilibrium is reached w/in a fraction of a second
150
Carbonic acid dissasociates into what?
Hydrogen and Bicarbonate ions
151
H2CO3 is what? And it disassociates into what?
Carbonic acid
H+ and HCO3-
152
\_\_\_\_\_\_ diffuses from the RBC in exchange for ______ ion
HCO3
Chloride ion
\*Chloride or Hamburger shift\*
153
CO2 binding with Hgb forms what?
Carbaminohemoglobin
CO2Hgb
154
How is CO2 carried in plasma? %?
7% dissolved in plasma
23% bound to Hgb
70% carried as bicarb
155
closing volume increase with:
inc Closing Volume with:
**age**
**obstructive dz**
(used to detect small airway disease)
156
normal FEV1
1. 0.5 sec
2. 1 sec
3. 2 sec
4. 3 sec
normal FEV1
1. 0.5 sec **50 - 60%**
2. 1 sec **75 - 80%**
3. 2 sec **94%**
4. 3 sec **97%**
157
examples of restrictitve dz:
acute intrinsic
**pulm edema**
**asp pneumon'ier**
**ARDS**
158
examples of restrictitve dz:
Chronic intrinsic
Fibrosis
1. IPF
2. radiation injury
3. cytotoxic/noncytotoxic drug exposure
4. O2 toxicity
5. autoimmune dz
6. sarcodosis
159
examples of restrictitve dz:
chronic extrinsic
inhibit excursion:
1. obesity
2. ascities
3. prego
4. RA
5. Neuromuscular dz
6. Flail chest
7. pneumothorax
8. pleural effusions
160
Not considered part of Obstructive Disease process
**TB**
**cystic fibrosis**
**bronchiectasis**
161
relationship of muscle paralysis to FRC
MP does not change FRC significantly
162
