Acidosis + Alkalosis

Decrease, increase, increase, increase

Respiratory Acidosis

• pH =

• Plasma PaCO2 =

• Plasma [H+] =

• Plasma [HCO3-] =

(Increase or decrease)

Increase, decrease, decrease, decrease

Respiratory Alkalosis

• pH =

• Plasma PaCO2 =

• Plasma [H+] =

• Plasma [HCO3-] =

(Increase or decrease)

Decrease, decrease, increase, decrease

Metabolic Acidosis

• pH =

• Plasma PaCO2 =

• Plasma [H+] =

• Plasma [HCO3-] =

(Increase or decrease)

Increase, increase, decrease, increase

Metabolic Alkalosis

• pH =

• Plasma PaCO2 =

• Plasma [H+] =

• Plasma [HCO3-] =

(Increase or decrease)

Electroneutrality

Concentration of cations and anions equal in each fluid compartment

Na+, HCO3-, Cl-

Ions commonly measured in plasma

• Cations: __

• Anions: __ and __

Anion Gap

Represents all anions not measured outside of plasma (i.e. proteins, phosphate, etc)

(Na+) - (HCO3-) - (Cl-), 10

• Anion gap formula = 

• Anion gap normal concentration = __ mEq/L

Metabolic acidosis, anion, Cl-, elevated

• Anion gap is useful for differential diagnosis for __ __

  • Lost HCO3– in this condition must be replaced by another __ to maintain electroneutrality

  • If replaced by another unmeasured anion (NOT __): Have an __ anion gap (Ex: Ketoacidosis, aspirin toxicity)

Hyperchloremic, acidosis, normal

• __ metabolic __: If lost HCO3- replaced by chloride 

  • Outcome is a __ anion gap

  • (Ex: HCO3- loss via kidney or diarrhea)

Non-anion, HCO3-, Cl-, diarrhea

• __-anion gap (hyperchloremic) metabolic acidosis

  • Kidneys, pancreas, RBCs, and other cells directly exchange __ for __ (2 anions)

  • Causes - Renal HCO3- wasting, impaired renal H+ secretion, GI HCO3- wasting (aka __- GI sx)

Respiratory Acidosis/Alkalosis

Change in CO2 → pH and HCO3- move in opposite directions

Metabolic Acidosis/Alkalosis

pH and HCO3- move in same direction

Normal (Non-anion gap)

Result of diarrhea or renal HCO3- wasting

Elevated Anion Gap

Anion gap > 10 AND MUDPILES diagnoses

Uremia, diabetic ketoacidosis, lactic acid, salicylates

Elevated Anion Gap Causes - Udls

• __ (late-stage CKD)

• __ __ (endoc)

• __ __ (muscle)

• __ (aspirin)

Metabolic pH issue

BOTH Respiratory and renal compensation available for…

(metabolic vs respiratory pH issue)

Respiratory pH issue

Renal compensation by itself is ONLY available for…

(metabolic vs respiratory pH issue)

Hypoventilation, right, HCO3-, H+

Respiratory Acidosis

• CO2 retention AFTER alveolar __

•  High CO2 shifts reaction to the __

• Hallmark feature - decreased pH with elevated __

• Renal compensation: Retain HCO3- and excrete __

Hyperventilation, left, HCO3-

Respiratory Alkalosis

• CO2 depletion AFTER alveolar __

•  Low CO2 shifts reaction to the __

• Renal compensation: Retain H+ and excrete __

Dietary, H+, left, PaCO2, H+

Metabolic Acidosis

• Metabolic or __ input of __ exceeds buffering/excretion

• Elevated H+ shifts reaction to the __

• Hallmark feature - Hyperventilation leads to low __ from compensatory

• Renal compensation: Excrete __ and retain HCO3-

H+, right, PaCO2, HCO3-

Metabolic Alkalosis

• Excessive buffering of __

• Low H+ shifts reaction to the __

• Hallmark feature - Hypoventilation leads to high __ from compensatory

• Renal compensation: Retain H+ and excrete __

Impairs, hyperkalemia, uncoordinated, hypercalcemia, block

Acidosis__ (excites/impairs) membrane excitability

• H+ enters cells and K+ exits cells → __ (-emia)

• Depolarization can lead to __ firing of voltage-gated sodium channels

• H+ displaces Ca2+ from proteins like albumin → __ (-emia)

  • Ca2+ can __ voltage sodium channels and decrease excitability

Excites, hypokalemia, hypocalcemia, inhibition

Alkalosis__ (excites/impairs) membrane excitability

• H+ enters cells and K+ enter cells → __ (-emia)

• More Ca2+ binds to proteins like albumin → __ (-emia)

  • Less __ of voltage sodium channels by Ca2+ = hyperexcitability