Gas Exchange Flashcards
1
Q
Acid base balance is regulated to maintain
A
Normal ph
2
Q
Two forms of body acids
A
Volatile and nonvolatile
3
Q
Volatile
A
Carbonic acid H2CO3
Eliminated as CO2 gas and water
4
Q
Nonvolatile
A
Sulfuric, phosphoric, and other organic acids
Eliminated by renal tubules
Regulated by bicarbonate HCO3
5
Q
What is a buffer
A
Chemical that can bind to excess H or OH without large change to ph
6
Q
Most important plasma buffering system
A
Carbonic acid bicarbonate pair
7
Q
Protein buffering system
A
Proteins have negative charge
Can buffer H+
8
Q
Renal buffering
A
Secretion of H+ in the urine and reabsorption of HCO3-
9
Q
Where does carbonic acid bicarbonate pair happen
A
Lungs and kindeys
10
Q
Greater partial pressure of CO2 =
A
More carbonic acid H2CO3 formed
Both can increase but the ratio must be maintained
11
Q
Respiratory system compensation with carbonic acid bicarbonate pair
A
Increase ventilation to get rid of CO2
Or
Decrease ventilation to retain CO2
12
Q
Renal system compensation with carbonic acid bicarbonate pair
A
Produces acidic or alkaline urine
13
Q
Normal arterial blood ph
A
7.35-7.45
14
Q
Acidosis
A
System increase in H+ concentration or decrease in bicarbonate
15
Q
Alkalosis
A
System decrease in H+ or increase in bicarbonate
16
Q
Normal pCO2
A
35-45
17
Q
Normal HCO3
A
22-26
18
Q
Resp acidosis
A
High paco2
Ventilation depression
Low ph high paco2
19
Q
Resp alkalosis
A
Low paco2
Alveolar hyperventilation
High ph low paco2
20
Q
Metabolic acidosis
A
Low HCO3 or increase in noncarbonic acids
Ph low HCO3 low
21
Q
Metabolic alkalosis
A
High HCO3
Excessive loss of metabolic acids
Ph high HCO3 high
22
Q
Fully compensated
A
Ph normal
23
Q
Partially compensated
A
All 3 abnormal
24
Q
Uncompensated
A
PCO2 or HCO3 is normal, other is abnormal
25
Causes of impaired gas exchange
Ineffective ventilation
Reduced capacity for gas transport (reduced hemoglobin/RBC)
Inadequate perfusion
26
COPD diagnostic studies
Chest X-ray
Spirometry
History
Physical exam
27
COPD spirometry findings
Reduced FEV1/FVC ratio
| Increased residual volume
28
COPD ABG findings
Low PaO2
High PaCo2
Low ph
High bicarbonate (late stage)
29
COPD oxygen therapy used for
Reduce work of breathing
Maintain PaO2
Reduce cardiac work load
30
COPD oxygen therapy humidification
Use humidifiers because O2 dries mucosa
31
Complication of oxygen therapy
```
Combustion
CO2 narcosis
O2 toxicity
Absorption atelectasis
Infection
```
32
What do bronchodilators do
Relax bronchial smooth muscles causing bronchodilation
33
Three classes of bronchodilator
Beta-adrenergics agonists
Anticholinergics
Xanthine derivatives
34
Beta adrenergic agonists action
Dilate airways
| Stimulate beta 2 adrenergic receptors in lungs
35
Beta adrenergic agonists adverse effects
```
Insomnia
Restlessness
Anorexia
Heart stimulation
Hyperglycemia
Tremor
Vascular headache
Tachycardia
Angina pain
Hyper/hypotension
```
36
Beta agonists bronchodilator drugs
```
Ephedrine
Epinephrine
Fenoterol
Formoterol
Isoproterenol
Salbutamol
Salmeterol
Terbutaline
```
37
Salbutamol sulphate
```
Ventolin
Short acting
Most common
Route: inhalation
Onset: immediate
Peak: 10-25 min
Half life: 3-4 hours
Duration of action: 3-4 hours
```
38
Anitcholinergics action
Prevents ACh from binding to receptors
Allows bronchodilation
Reduce secretions in people with COPD
39
Anticholinergics adverse effects
```
Dry mouth/throat
Nasal congestion
Heart palpitations
GI distress
Urinary retention
Increased intraocular pressure
Headache
Cough
Anxiety
```
40
Ipratropium bromide
```
Atrovent
Anticholinergic
Oldest most common
Liquid aerosol and inhaler
Route: inhalation
Onset: 5-15 min
Peak: 1-2 hours
Half life: 1.6 hours
Duration of action: 4-5 hours
```
41
Xanthine derivatives action
Cause bronchodilation
Increase levels of cAMP
Stimulates CNS which I handles respiratory drive
42
Xanthine derivatives adverse effects
```
Nausea
Vomiting
Anorexia
Gastroesophogeal reflux
Tachycardia
Extrasytole
Palpitations
Ventricular dysrhythmias
```
43
Corticosteroids action
Reduced inflammation
| Enhance activity of B-agonists
44
Fluticasone propionate
Flovent
Route: inhalation
Half life 3 hours
Duration: up to 24 hours
45
Antitussives action
Suppress cough reflex
Act directly on cough Center in the CNS
Reduce runny nose and post nasal drop by drying mucosa
46
Expectorants action
Reduce the thickness of bronchial secretions
| Increases mucous flow so it can be easily removed by coughing
47
What is asthma
Chronic inflammation disorder of the airways
48
Asthma triggers
```
Allergens
Exercise
Respiratory infection
Nose and sinus problems
Drug and food additives
GERD
Air pollutants
Emotional stress
```
49
Early phase of asthma
Bronchospasm
Increased mucous secretions, edema formation, increased amounts of tenacious sputum
Peaks in 30-60 mins after exposure
Subsides in about 30-90 mins
50
Asthma late phase response
```
More severe
Primary response is inflammation
Peaks 5-12 hours
Can last hours to days
Corticosteroids effective
```
51
asthma inspiration expiration ratios
1: 2
1: 3
1: 4
52
Asthma complications
Severe acute attack
| Severe asthma attack
53
Severe acute attack causes
```
Viral illness
Ingestion of aspirin or other NSAIDS
increased environmental pollutants
Allergen exposure
Discontinuation of drug therapy
```
54
Severe asthma attack clinical manifestation
Similar to non severe asthma
| More serious and prolonged
55
Severe asthma attack
Pneumothorax
Pneumomediastinum
Acute cor pulmonale with right ventricular failure
Severe respiratory muscle fatigue that leads to respiratory arrest
56
Asthma diagnostic studies
```
History
Physical exam
Pulmonary function test
Peak flow monitoring
Chest X-ray
ABG
Oximetry
Allergy testing
Blood levels of eosinophils
Sputum culture and sensitivity
```
57
Three categories of medication used to treat asthma
Mast cell stabilizers
Leukotrine modifiers
Glucocorticoids
58
Mast cell stabilizers action
Inhibit release of inflammatory chemicals (histamines) from mast cells
Makes airways less likely to construct
Anti-inflammatory in nature
59
Mast cell stabilizers indication
Prevent but do not treat attacks
| Help people with exercise induced asthma
60
Mast cell stabilizers prototypes
Cromolyn (crolomintal) and nedocromil (alocril)
61
Leukotriene modifiers/antagonists
Anti-inflammatories that prevent the action/synthesis of leukotrienes
Prevent inflammation, bronchoconstriction and mucous production
Can be used during an attack
62
Leukotriene modifiers/antagonists prototypes
Monetelukast (singulair)
Zarfirlukast (accolate)
Zileuton (zyflo)
63
Leukotriene modifiers/antagonists action
Bund to D4 leukotriene receptor subtypes in the respiratory tract
Prevent leukotrienes from attaching to receptors on immune cells
64
Montelukast sodium
```
Singulair
Approved use in children 2+
Fewer side effects
Route: PO
Onset: 30 mins
Peak: 3-4 hours
Half life: 2.7-5 hours
Duration of action: 24 hours
```
65
Status asthmaticus
Severe attack that does not reposed to pharmacotherapy
| Life threatening
66
What happens during status asthmaticus
```
Bronchospasm not reversed
Hypoxemia develops
Hypercapnea (respiratory acidosis) develops
Silent chest (no audible air movement)
paCO2 greater than 70
```
67
Status asthmaticus symptoms
```
Decreased consciousness
Use of accessory muscles
Increased respiratory rate
Wheezing
Increased fatigue
Increased heart rate
Inflammation if airway
Decreased oxygen level
```
68
Status asthmaticus first line of treatment
Beta antagonists
Rapid relief of bronchospasms
Provide immediate bronchodilation
69
Status asthmaticus second line of treatment
IV corticosteroids
| Highly effective anti inflammatory drugs
70
Status asthmaticus third line of treatment
Theophylline
Smooth muscle relaxation causing optimal bronchodilation
Ensuring optimal cardiac functioning
71
Status asthmaticus other medications
Anticholinergics: decrease mucous production and increase bronchodilation
Sedatives: calms anxiety
Anesthetics: relaxes smooth muscle
72
Status asthmaticus additional treatment
IV fluid
Monitor oxygen level via ABG
Oxygen support
If oxygen support not enough, may need to be ventilated
73
Inhalation of pulmonary drugs
| Aerosol methods
Nebulizers
Dry powder inhaler
Metered dose inhaler
74
Advantages of inhaled pulmonary drugs
Delivers drug to immediate site of action
| Reduces systemic effects
75
Disadvantages of inhaled pulmonary drugs
Precise dosing is difficult
| People dont use device and spacer correctly
76
Acute intervention
```
Monitor respiratory and cardiovascular system
Kung sounds
Respiratory rate
Pulse
BP
```
77
Peak flow
| Green zone
80-100% of personal best
| Remain on medication
78
Peak flow
| Yellow zone
50-79% of personal best
Indicates caution
Something is triggering asthma
79
Peak flow
| Red zone
56-60% of personal best
Indicates serious problem
Action to be taken with health care provider
