Pharm Care: Acid/base Balance

Front 1

ABG

Back 1

Arterial Blood Gases

Front 2

Normal range for Carbon Dioxide?

Back 2

24-30 mEq/L

Front 3

How is the total carbon dioxide determined?

Back 3

By acidifying serum to convert all bicarb (HCO3-) to carbon dioxide (CO2)

Front 4

What percentage of serum CO2 is converted bicarbonate?

Back 4

95%

Front 5

What organ regulates bicarbonate?

Back 5

kidneys

Front 6

What organ regulates CO2?

Back 6

lungs

Front 7

What is the main cause of hypercapnia?

Back 7

Chronic obstructive pulmonary disorder

Front 8

COPD

Back 8

chronic obstructive pulmonary disorder

Front 9

What is the main cause of Hypocapnia?

Back 9

hyperventilation

Front 10

Define Acid

Back 10

A substance that can donate protons (Hydrogen ion, H+)

Front 11

Define Base

Back 11

a substance that can accept protons (hydrogen ions)

Front 12

FACT: All basses are alkaline substance

Back 12

*Make sure you remember this*

Front 13

Identify the acid:

HCL --> H+ + Cl-

Back 13

HCl

Front 14

Identify the base:

NH3 + H+ --> NH4+

Back 14

NH4+

Front 15

Define pH

Back 15

A measurement indicating body's acid-base balance; quantifies the acidity of body fluids

Front 16

Definition: A measurement indicating body's acid-base balance; quantifies the acidity of body fluids

Back 16

pH

Front 17

Acidemia

Back 17

acid concentration of the blood (pH <7.35)

Front 18

Alkalemia

Back 18

alkaline concentration of the blood (pH > 7.45)

Front 19

Acidosis

Back 19

process that lowers pH

Front 20

Alkalosis

Back 20

process that increases pH

Front 21

Alkalosis

Back 21

process that increases pH

Front 22

What is the normal pH of arterial blood? (range)

Back 22

7.35-7.45

Front 23

What is the main organ system regulating gas exchange and arterial partial pressure of carbon dioxide? (paCO2)

Back 23

lungs

Front 24

CO2 diffuses from ______ to __________ and from ____________ into _________ where it is exhaled from the body by the lungs.

Back 24

tissues; capillary blood; pulmonary capillaries; alveoli; lungs

Front 25

____ and ____ combine to form H2CO3.

Back 25

CO2 and H2O

Front 26

What enzyme catalyzes the formation of H2CO3?

Back 26

Carbonic anhydrase

Front 27

Dissociation of _____ to ______ is an important part of the extracellular buffering system.

Back 27

H2CO3; HCO3-

Front 28

Name three intracellular/extracellular buffers.

Back 28

1. serum proteins
2. inorganic phosphates
3. hemoglobin

Front 29

What organ regulates reabsorption of HCO3- and the excretion of H+

Back 29

kidneys

Front 30

How is pH maintained?

Back 30

through regulatory actions of the lungs and kidneys

Front 31

How is pH maintained?

Back 31

through regulatory actions of the lungs and kidneys; also maintained through buffers

Front 32

What equation describes the relationship between the pH and the concentration of the acid-base concentration?

Back 32

Henderson-Hasselbach equation

Front 33

The Henderson-Hasselbach equation describes the relationship between the _____ and the concentration of the _______/_______ concentration.

Back 33

pH, acid/base

Front 34

What is the Henderson-Hasselbach equation? (actual equation)

Back 34

pH = pKa + log(base/acid)

Front 35

What is the rewritten H-H equation for the HCO3-H2CO3 system?

Back 35

pH = 6.1 + log (HCO3-/0.03 * pCO2)

Front 36

What sets the pH?

Back 36

ratio of the bicarbonate and carbon dioxide (not absolute values)

Front 37

Define O2 saturation

Back 37

Definition: Percentage that represents the ratio of the amount of O3 that hemoglobin IS carrying to the amount of O2 that hemoglobin CAN carry

Front 38

What is the format of ABG:

_/_/_/_/_

Back 38

pH/pCO2/pO2/HCO3-/O2saturation

Front 39

Normal ABG values for pH?

Back 39

7.35-7.45

Front 40

Normal ABG values for pCO2?

Back 40

35-45 mmHg

Front 41

Normal ABG values for pO2?

Back 41

80-100 mmHg

Front 42

Normal ABG values for HCO3-?

Back 42

24-30 mEq/L

Front 43

Normal ABG values for O2 saturation?

Back 43

95% or greater

Front 44

What is the normal range of venous total CO2?

Back 44

24-28mEq/L

Front 45

What do arterial samples tell the physician?

Back 45

provides information abouthow well the lungs are oxygenating the blood (PaO2)

Front 46

Normal range for Anion gap?

Back 46

3 - 11 mEq/L

Front 47

AG

Back 47

Anion Gap

Front 48

Why is the anion gap calculated?

Back 48

When metabolic acidosis is present, anion gap should be calculated to try to determine the cause of metabolic acidosis

Front 49

T/F: You can have metabolic acidosis with a normal anion gap?

Back 49

True

Front 50

Formula for Anion Gap?

Back 50

Anion Gap = (Na+) - (Cl- + HCO3-)

Front 51

What does anion gap count for?

Back 51

the difference between the sum of the measured cations and the sum of the measured anions

Front 52

What does the result (number) of the anion equation represent?

Back 52

the amount of extracellular anion needed to offset the positive charge of sodium and potassium and to maintaine electroneutrality

Front 53

Increased anion gap is valuable in determining the cause of ___________________.

Back 53

metabolic acidosis

Front 54

Mneumonic device for common causes of high anion gap?

Back 54

MULEPAK

Front 55

Common causes of Low anion Gap?

Back 55

Multiple myeloma
Major hypercalcemia
Lithium toxicity

Front 56

M in MULEPAK

Back 56

Methanol ingestion

Front 57

U in MULEPAK

Back 57

Uremia

Front 58

L in MULEPAK

Back 58

Lactic acidosis

Front 59

E in MULEPAK

Back 59

Ethylene glycol ingestion

Front 60

P in MULEPAK

Back 60

Paraldehyde ingestion

Front 61

A in MULEPAK

Back 61

Aspirin intoxication

Front 62

K in MULEPAK

Back 62

Ketoacidosis

Front 63

Common causes of high anion gap? (mneumonic)

Back 63

MULEPAK

Front 64

PLEASEEEEEEEEEEEEEEEEEEEEEEEE READ THE ACID/BASE CHAPTER!!!!!

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ITS VERY VERY IMPORTANT SAYS DR. MORRIS!!! AT LEAST STUDY THE HANDOUT ON THIS SECTION!! KNOW IT WELL! THANKS!!

Front 65

Two ways to return abnormal pH toward normal?

Back 65

Compenasation or corrections

Front 66

Define Compensation

Back 66

Definition: Abnormal pH is returned toward normal by altering the component NOT primarily affected

Front 67

Define Correction

Back 67

Definition: Abnormal pH is returned toward normal by altering the componet primarily affected

Front 68

In compensation, if pCO2 increases, the _____ will increase _____ reabsorption to bring the pH toward normal

Back 68

kidneys;HCO3-

Front 69

In compensation, if HCO3- decreases, the ______ will respond by blowing off _______ to bring pH toward normal

Back 69

lungs;CO2

Front 70

List some causes of Metabolic Acidosis

Back 70

-overproduction of acid: ketoacidosis, lactic acidosis
-administration of acid(as in TPN)
-undersecretion of acid load: renal insufficiency
-HCO3 loss: diarrhea, renal tubular acidosis

Front 71

Signs and Symptoms: thirst, SOB, weakness, dehydration, tachypnea, restlessness, impaired consciousness,coma

Back 71

Metabolic acidosis

Front 72

List s/s of metabolic acidosis

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Signs and Symptoms: thirst, SOB, weakness, dehydration, tachypnea, restlessness, impaired consciousness,coma

Front 73

Laboratory findings: blood pH, pCO2 and serum HCO3 low, anion gap may or may not be elevated, BUN, Scr may reflect degree of renal impairment due to dehydration, increased K+ and Ca2+, ketone bodies in urine and serum with diabetic or alcoholic ketoacidosis

Back 73

metabolic acidosis

Front 74

List some lab findings of metabolic acidosis

Back 74

Laboratory findings: blood pH, pCO2 and serum HCO3 low, anion gap may or may not be elevated, BUN, Scr may reflect degree of renal impairment due to dehydration, increased K+ and Ca2+, ketone bodies in urine and serum with diabetic or alcoholic ketoacidosis

Front 75

Etiologies: acid loss, bicarbonate gain, hypokalemia, increased anion gap

Back 75

metabolic alkalosis

Front 76

Etiologies of metabolic alkalosis

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Etiologies: acid loss, bicarbonate gain, hypokalemia, increased anion gap

Front 77

Metabolic acidosis vs. Metabolic alkalosis

Back 77

lowered blood ph and bicarbonate; increased ph and increased bicarbonate conc.

Front 78

Causes of increased anion gap

Back 78

-loss of H+
-incease in negative charge of plasma proteins
-ECF volume deficit
-increased concentration of the plasma proteins

Front 79

Compensatory mechanism: extracellular buffering by HCO2, renal H+ excretion, hyperventilation to decrease pCO2

Back 79

METABOLIC ACIDOSIS

Front 80

Compensatory mechanism of Metabolic acidosis

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Compensatory mechanism: extracellular buffering by HCO2, renal H+ excretion, hyperventilation to decrease pCO2

Front 81

Compensatory mechanism of metabolic alkalosis

Back 81

Compensatory mechanisms: hypoventilation to increase pCO2, H+, reabsorption by kidneys

Front 82

Compensatory mechanisms: hypoventilation to increase pCO2, H+, reabsorption by kidneys

Back 82

metabolic alkalosis

Front 83

S/S: impaired mentation, hypotension, cardiac arrhythmias, hypoventilation, weakness and hyporeflexia if K+ is low

Back 83

metabolic alkalosis

Front 84

S/S of metabolic alkalosis

Back 84

S/S: impaired mentation, hypotension, cardiac arrhythmias, hypoventilation, weakness and hyporeflexia if K+ is low

Front 85

Lab findings of metabolic alkalosis

Back 85

Lab findings: arterial blood ph>7.45, increased HCO2, increased arterial pCO2, increased anion gap may be present

Front 86

Lab findings: arterial blood ph>7.45, increased HCO2, increased arterial pCO2, increased anion gap may be present

Back 86

metabolic alkalosis

Front 87

Etiologies of respiratory acidosis

Back 87

Etiologies:
-CNS depression (impaired resp. drive)
-Neuromuscular disorders (trauma, stroke, brain stem injury)
-Pulmonary disease: pneumonia, smoke inhalation

Front 88

Etiologies:
-CNS depression (impaired resp. drive)
-Neuromuscular disorders (trauma, stroke, brain stem injury)
-Pulmonary disease: pneumonia, smoke inhalation

Back 88

respiratory acidosis

Front 89

Another name for respiratory acidosis

Back 89

hypoventilation

Front 90

Compensation mechanisms for respiratory acidosis (acute response)

Back 90

Compensation mechanisms (acute response):
-increase in pco2 results in inc. carbonic acid levels
-carbonic acid dissociates, relasing H ions which are buffered by nonbicarbonate buffers and also by bicarbonate

Front 91

Compensation mechanisms for respiratory acidosis (renal response)

Back 91

HCO3 retention (may take several days to fully compensate)

Front 92

~ how long does it take the renal (metabolic) response to compensate for respiratory acidosis?

Back 92

may take serveral days to compensate

Front 93

S/S of respiratory acidosis

Back 93

s/s: somnolence, confusion, asterixis, SOB, cyanosis, hypertension, tachycardia

Front 94

s/s: somnolence, confusion, asterixis, SOB, cyanosis, hypertension, tachycardia

Back 94

respiratory acidosis

Front 95

What is somnolence?

Back 95

REAL SLEEPY

Front 96

What is asterixis?

Back 96

hand tremors

Front 97

Lab findings for respiratory acidosis

Back 97

Lab findings: arterial blood pH is decreased, pCO2 increased, serum HCO3 is elevated by not enough to completely compensate for the hypercapnia

Front 98

Lab findings: arterial blood pH is decreased, pCO2 increased, serum HCO3 is elevated by not enough to completely compensate for the hypercapnia

Back 98

respiratory acidosis

Front 99

Respiratory acidosis vs respiratory alkalosis

Back 99

decreased ph, increased pCO2 VS. increased ph, decreased pCO2

Front 100

What is another name for respiratory alkalosis?

Back 100

hyperventilation

Front 101

Etiologies of respiratory alkalosis

Back 101

Etiologies: anxiety, hypoxemia, pulmonary disease, liver disease, gram negative sepsis, incorrectly used mechanical ventilator, pregnancy, drugs

Front 102

Etiologies: anxiety, hypoxemia, pulmonary disease, liver disease, gram negative sepsis, incorrectly used mechanical ventilator, pregnancy, drugs

Back 102

respiratory alkalosis

Front 103

Acute compensation mechanism for respiratory alkalosis

Back 103

Acute compensation mechanism: chemical buffering - H+ ions are released from the bodys buffers - intracellular proteins, phosphates and hemoglobin which decreases the serum bicarb conc.

Front 104

Acute compensation mechanism: chemical buffering - H+ ions are released from the bodys buffers - intracellular proteins, phosphates and hemoglobin which decreases the serum bicarb conc.

Back 104

respiratory alkalosis

Front 105

Metabolic compensation mechanism: occurs when [disease state] persisists for more than 6-12 hours; bicarb reabsorption is inhibited and serum bicarb falls, usually complete renal compensation within 1-2 days

Back 105

respiratory alkalosis

Front 106

Metabolic compensation mechanism for respiratory alkalosis

Back 106

Metabolic compensation mechanism: occurs when [disease state] persisists for more than 6-12 hours; bicarb reabsorption is inhibited and serum bicarb falls, usually complete renal compensation within 1-2 days

Front 107

How long does respiratory alkalosis persist before metabolic compensation mechanisms occur?

Back 107

6-12 hours

Front 108

S/S of respiratory alkalosis

Back 108

S/S: hyperventilation, angina, arrhythmias, lightheadedness, anxiety, tingling sensation, numbnessa round the mouth, N/V

Front 109

S/S: hyperventilation, angina, arrhythmias, lightheadedness, anxiety, tingling sensation, numbnessa round the mouth, N/V

Back 109

respiratory alkalosis

Front 110

Lab findings for respiratory alkalosis

Back 110

Lab findings: increased pH, low pCO2, decreased serum HCO3-

Front 111

Lab findings: increased pH, low pCO2, decreased serum HCO3-

Back 111

respiratory alkalosis