Acid Base balance Flashcards
What is acid base balance?
- body maintains balance for optimal cell function
- represents homeostasis of H ion concentration in body fluids
- arterial pH is indirect measurement of H ion concentration
- increase of H= decrease of pH
How acid base balance is produced
cellular metabolism creates 2 types of acids
1. carbonic converts to CO2
2. metabolic
How its balanced
- buffering
- releases H ions or takes them
- maintains/controls
Buffering
- all body fluids have buffers
- main one is in ECF is bicarb
- consists of lots of bicarb and small amount of carbonic acid
- bicarb can release or accept it
HCO3 is
basic
CO2 is
acidic
Lung excrete
carbonic acid
Kidneys excrete
metabolic acid
When you exhale you
excrete carbonic in the form of CO2
When you urinate you
excrete metabolic (all other acids except carbonic)
Blood Ph scale range is
7.35- 7.45
PaCO2 range and definition
How well lungs are getting CO2 out
35-45
HCO3 range and definition
how well the kidneys are excreting metabolic
21-28
PaO2 range and definition
alveoli function and O2 in blood
80-100mmHg
SaO2 range and definition
how much O2 the hemoglobin is carrying
95-100%
Base excess range and definition
chemical buffers that regulate pH
-2 - +2 mEq/L
Acid base imbalances
develops when normal regulating mechanisms are dysfunctional/overwhelmed
- body compensates change
- kidneys/lungs make up for loss
Types of acidosis
respiratory and metabolic
Types of alkalosis
respiratory and metabolic
Respiratory acidosis
- lungs unable to excrete CO2
- excess CO2 in the blood decreases pH
ex. COPD ineffectively able to exhale
Causes of respiratory acidosis
- pneumonia
- asthma
- airway obstruction
- chest wall injury
- drug overdose
- head injury
Respiratory acidosis ABG
pH= decreased
CO2= increased
HCO3= normal
Respiratory alkalosis
lungs excreting too much CO2
decrease CO2=increase pH
Hyperventilation causes
respiratory alkalosis
respiratory alkalosis is caused by
- acute pain
- anxiety
- psychological distress
- respiratory control
- stimulation of brainstem
Metabolic acidosis
increased metabolic= decreased in HCO3
kidneys cant excrete enough metabolic which accumulates in blood or HCO3 is removed from body
metabolic acidosis is caused by
- diabetic ketoacidosis
- burns
- severe infection
- diarrhea
- end-stage renal disease
- acute kidney injury
metabolic acidosis ABG
pH: decreases
HCO3: decreases
CO2: normal
metabolic alkalosis
increase of HCO3 and decrease of metabolic
HCO3 in blood increases
metabolic alkalosis is caused by
- vomiting
- NGT suctioning
- blood transfusion
- too much sodium bicarb
metabolic alkalosis ABG
pH: increases
HCO3: increases
CO2: normal
Respiration alkalosis ABG
pH: increases
CO2: decreases
HCO3: normal