Acid Base Flashcards
1
Q
What is the normal range for arterial blood pH
A
7.35-7.45
2
Q
What is ABG stand for? What does it test?
A
Arterial Blood Gas
Tests for CO2, O2, pH
3
Q
What are normal pH values for venous blood?
A
7.31-7.41
4
Q
What are the four major changes that are caused by pH extremes
A
- Hormones and enzymes denature
- Shifts electrolytes causing F&E imbalances
- Changes the excitability of membranes
- Decreases the effectiveness of drugs and hormones
5
Q
What are the three roles of the nurse r/t acid-base imbalance
A
- Prevent disorders
- Detect disorders
- Know the interventions
6
Q
What is the function of an acid?
A
It releases hydrogen when it dissolves in water
Donates hydrogen ion
7
Q
What is the function of a base?
A
Binds to hydrogen when dissolved in water
Receives Hydrogen Iron
8
Q
What type of acid is HCl? Give the formula
A
Strong
HCl + H2O H+ + Cl + H2O
9
Q
What type of acid is Acetic acid? what is its formula?
A
Weak acid
CH3COOH + H2O H+ + CH3COO- + H2O
10
Q
What is a buffer?
A
something that can accept/release hydrogen ions
11
Q
What are the two classifications of buffer system?
A
Chemical and Physiologic
12
Q
For every 1 point change in pH the substance has a concentration of H+ _____ times more/less than before
A
100
13
Q
What is the lowest pH before death?
A
6.9
14
Q
What is the highest pH before death?
A
7.8
15
Q
What four things can lead to Metabolic Acidosis?
A
- Over production of H+
- Under-elimination of H+
- Unproduction of Bicarb
- Over elimination of Bicarb
16
Q
What 3 things can cause an over production of H+?
A
- Excessive breakdown of fatty acids
- Anaerobic glucose breakdown (lactic acidosis)
- Excessive intake of acids
17
Q
Where does most H+ loss occur?
A
Lungs and Kidneys
18
Q
What two things can cause under-elimination of H+?
A
- Kidney tubules cant excrete H+
- Lungs retain CO2 which corresponds with H+ retention
19
Q
What can cause underproduction of Bicarb Ions?
A
Impaired liver or pancreatic function
20
Q
What is a base deficit?
A
a low bicarb level
21
Q
What can cause an over-elimination of bicarbonate?
A
Diarrhea
22
Q
What is the most influential base in the body
A
Bicarb
23
Q
What buffer system is the first line of defense? This is also the strongest in the body
A
Chemical buffers
24
Q
What are the three chemical buffer systems in the body?
A
- Bicarb/carbonic acid
- Phosphate buffer system
- Protein Buffer system
25
The body likes to keep what ratio of Bicarb to acid?
20:1
26
The bicarb buffer system is tied to what body systems?
Respiratory and Renal
27
What is the formula for the Bicarb buffer system?
CO2 + H2O <> H2CO3 <> H+ + HCO3
28
What two things in the body are considered H+ sponges?
Bicarb and Phosphates
29
Where does the phosphate buffer system act?
In bothe the IFC and the EFC
30
Where does the phosphate buffer system occur the most?
in the renal tubules
31
What is the function of the phosphate buffer system?
To help excrete acid
32
What is the formula for the phosphate buffer system?
H+ + HPO4 <> H2PO4 (which can be excreted)
33
What proteins are used in the protein buffer system?
Hemoglobin, Albumin, and other globulins
34
the actions of the chemical buffers occur within _____
seconds
35
The two types of physiological buffers are?
Respiratory and Renal
36
What is the second line of defense buffer?
Respiratory
37
How fast does the respiratory buffer system kick in?
2-3 minutes
38
Unlike the chemical buffer system. respiratory buffer systems need _____ to kick in
Energy and effort
39
What is the main action of the respiratory buffer system?
To adjust ventilation in response to changing pH levels
40
Explain the process of the respiratory buffer system.
- Medulla detects change in pH
- changes respiratory rate
- amount of CO2 is then adjusted via ventilation
41
The respiratory biffer system is ____ as effective than chemical
Twice
42
What is the normal PaCO2 range?
35-45
43
What is the most efficient buffer system?
renal
44
How long does the renal system take to respond?
Hours
45
What three actions do the kidneys take to buffer pH
- Produce and regulate bicarb
- Form acids
- Form Bases
46
What is the normal PaHCO3 range
22-26
47
What are the 4 different acid base imbalances?
Metabolic and Respiratory Acidosis
| Metabolic and Respiratory Alkalosis
48
Metabolic issues cause _____ compensation
Respiratory
49
Respiratory issues cause _____ compensation
Metabolic
50
What is partial compensation?
pH remains abnormal
51
What is full compensation
pH returns to normal
52
When will the body overcompensate?
Never. We can cause the over compensation through drugs or holding our breath
53
Anion gap is only relevant in ____ disorders
Metabolic
54
What is actual acidosis?
The over production of acid or the under elimination of acid
55
What is realative acidosis?
The amount or the strength of base decreases
56
What caused actual acidosis?
Problems that increase acid production such as DKA and seizures
Problems that decrease acid elimination such as respiratory or renal impairment
57
What are 4 causes of realitive acidosis?
- Over elimination/underproduction of bicarb
- Problems that cause underproduction of base(Pancreatitis or dehydration)
- Problems that cause over elimination of base (diarrhea)
- Increase of H+ or decrease of bicarb linked to K (AP is used up and decreased excitability)
58
What is the anion gap?
the difference between anions and cations
59
How is the anion gap calculated?
Na-(Cl + HCO3)
60
What is a normal Anion gap?
8-16
61
A high anion gap indicates ?
Metabolic Acidosis
62
And low anion gap indicates
Metabolic Alkalosis
63
What does the anion gap help us understand?
The underline cause of a compensation
64
What are the main causes for an increased anion gap?
Lactic acidosis, keto acidosis, ingestion of toxins (Methanol, etheleneglycol)
65
What does Base Excess tell us?
How much acid is required to return to normal
66
What is normal range for base excess?
-3 to +3
67
a high base excess indicates?
Metabolic alkalosis
68
A low base excess indicates?
Metabolic Acidosis
69
How do respiratory problems play into base excess?
They dont
70
How does acidosis manifest in the body?
First in the musculoskeletal, cardiac, respiratory, and CNS.
71
Even slight elevations in H+ can reduce the activity of _____
enzymes and hormones
72
What happend to K during anabolism?
K goes into cells and leaves the ECF
73
What happens to K during catabolism?
K leaves the cells as they break down and enters the ECF
74
The anion gap is effected by changes in the _____
levels of H+
75
The more H+ the _____ the anion gap
Higher
76
What is respiratory acidosis?
When respiratory function is impaired, gas exchanges is reduced and pH goes up because CO2 is retained
77
What four things can cause respiratory acidosis?
- Respiratory depression
- Inadequate chest expansion
- Airway obstruction
- Reduced alviolar-capillary disfusion
78
What is respiratory depression and what causes it?
Depressed function of the respiratory center
- Chemicals such as anesthetics, opioids, and poison
- Physical damage to brainstem
79
How does inadequate chest expansion cause acidosis? What are some causes for the inadequate expansion?
Reduced gas exchange from decreased volume
- Deformities, weakness, constriction
- obesity,scar tissue, and ascites
80
What are some causes of reduced alveolar-capillary diffusion?
- Pneumonia
- Pneumonitis
- TB
- Emphysema
- ARDS
- Chest trauma
- Drowning
81
How is pH effected in acute resp. acidosis?
it is decreased
82
How is pH effected in chronic resp. acidosis?
its normal
83
Give me an example of a pt who whole have combined metabolic and respiratory acidosis?
COPD and DKA
84
How does acidosis affect the cardiovascular system?
Arrhythmias due to hyperkalemia
85
How does respiratory acidosis affect the cardiovascular system uniquley?
increased HR
86
How does acidosis affect the CNS
Depression of function
87
How does acidosis affect the Neuromuscular system?
Reduced muscle tone and DTR due to hyperkalemia
88
How does metabolic acidosis affect the respiratory system?
causes rapid deep kussmaul respirations
89
How does respiratory acidosis affect the respiratory system?
Shallow, rapid, SOB
90
How does metabolic acidosis affect the skin
Causes vasodilation resulting in warmth, dry, and pink skin and MM's
91
How does respiratory acidosis present in the skin?
Cyanotic
92
What are three signs of acidosis in adults?
Weakness, depression, disorientated
93
A PaHCO3- of less than ____ is acidic
21
94
In metabolic acidosis ___ and ___ are normal levels
CO2 and O2
95
What are the interventions for metabolic acidosis?
- Remove the cause
- Restore fluids
- Give drugs
96
What are some drugs used to treat metabolic acidosis?
- Insulin
- Antidirrheal
- Bicarb if pH is below 7.1 *flush with NS before and after*
97
K levels are ___ in acute RA and ___ in chronic
Elevated
| normal
98
What are the interventions for Respiratory acidosis?
- Maintain the airway
- Enhance gass exchange
- Give O2
- Ventilation
99
What are some causes of alkalosis
- pH is too high
- H+ is too low
- Bicarb is too high
100
How does alkalosis present itself?
-Overexcitment of the CNS, neuromuscular, and CV system
