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Releasing a hydrogen atom makes the atom more:
ACIDIC
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Accepting or combining with hydrogen atoms makes the atom more of a:
BASE
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Acid-Base Balance--
regulation of hydrogen ions
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Acidity or alkalinit is measured as:
pH
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Normal pH Levels:
Ph- 7.35- 7.45
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More Hydrogen ions, More acidic = _______ pH
lower pH
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Lower hydrogen ions, More alkaline= _____ pH
higher pH
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3 ways to regulate the pH:
1. Intra- and extracellular buffering systems
2. Lungs- elimination of CO2
3. Kidneys- reabsorb HCO3 and eliminate hydrogen
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Body Proteins buffering sytem:
- Amphoteric
- Can release or bind hydrogen
- Vascular buffers- albumin and plasma globulins
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2. Bicarbonate Buffer System
- Uses carbonic acid and bicarbonate
- Acts rapidly
- CO2 eliminated by lungs
- Kidney can form bicarbonate
- Kidney can excrete bicarbonate
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What system is used in a rapidly declining patient because it is fast acting?
Bicarbonate Buffer System
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Transcellular Hydrogen-Potassium Exchange System
- Can move freely between compartments.
- Hydrogen in ECF, moves in cell in exchange for potassium.
- Potassium in ECF, moves in cell in exchange for hydrogen.
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Respiratory Mechanisms:
*Respiratory control of pH is rapid
*Can eliminate or retain CO2
*Normal CO2 is 35 to 45 mmHg
*Lungs cannot eliminate hydrogen
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Getting the body back as close to normal as possible:
- Compensation
- (**Lungs cannot eliminate hydrogen)
- **KNOW VALUES
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Renal Control Mechanisms
*Long-term regulator
- ROLES:
- Reabsorption of bicarbonate
- Excretion of hydrogen
Normal bicarbonate level- 22 to 26 mEq/L
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-alteration in bicarbonate concentration
Metabolic Disorders
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-alteration in carbon dioxide concentration
Respiratory Diseases
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-adjusts the pH toward normal, does not correct etiology. Different than cause (lungs, kidney)
- Compensation (other systems kick in to try to get the body back to where it needs to be)
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Metabolic Acidosis:
-Ph low < 7.35, bicarb low < 22
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What causes Metabolic Acidosis:
- Increased nonvolatile metabolic acids
- Decreased acid secretion by kidneys
- Excessive loss of bicarb
- Increased chloride
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Manifestations of Acidosis:
- GI- anorexia, N/V
- Neuro- Weakness, lethargy, confusion, stupor, coma
- CV- Bradycardia, dysrhythmias
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Compensation of Acidosis:
- ph low < 7.35
- bicarb low < 22
- PCO2 low <35
- Kussmaul’s breathing
- Hyperkalemia
- Acid urine
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Metabolic Alkalosis
pH high > 7.45, bicarb high > 26
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What causes Metabolic Alkalosis
- Loss of hydrogen/ gain of bicarb
- Cannot excrete excess bicarb
- Excessive alkali intake
- Hydrogen, chloride, potassium loss/bicarb retention
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Manifestations of Metabolic Alkalosis
- CV- Dysrhythmias, hypotension
- Neuro- Hyperreflexia, tetany, confusion, seizures
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*At what point is pH dangerously high (causing seizers, coma, respiratory, failure)
pH 7.55
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Compensation of Metabolic Alkalosis:
- pH high > 7.45,
- bicarb high > 26,
- PCO2 high > 45
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Respiratory Acidosis:
- pH high > 7.45,
- bicarb high > 26,
- PCO2 high > 45
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What causes respiratory acidosis:
- Hypoventilation
- Excessive CO2 production
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Manifestations of Respiratory Acidosis
- Sudden: Increased HR, B/P, Cerebral vasodilation
- Decreased neuro activity
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Compensation from Respiratory Acidosis:
- pH low < 7.35,
- PCO2 high > 45,
- bicarb high > 26
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Respiratory Alkalosis
Ph high > 7.45, PCO2 low < 35
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What causes Respiratory Alkalosis
- Hyperventilation
- Stimulation medullary respiratory center
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Manifestations of Respiratory Alkalosis:
- Neuro/decreased cerebral blood flow:
- light headed, numbness, tetany, seizures
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Compensation for Respiratory Alkalosis
ph high > 7.45, PCO2 low < 35, bicarb low < 22
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Interpreting:
*Look at pH (acidosis <7.35 or alkalosis >7.45)
- *Check CO2
- <35-alkalosis, >45- acidosis
- *Check HCO3
- <22- acidosis, >26- alkalosis
- *Check primary disorder (see chart)
- *Compensation (see chart)
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