[BIOCHEM]LAB_002_ABG INTERPRETATION.pdf

(002) ARTERIAL BLOOD GAS INTERPRETATION DR. ESPIRITU | 09/22/2020 OUTLINE Certain solutions can resist drastic changes in pH when I. ACID BA...

(002) ARTERIAL BLOOD GAS INTERPRETATION DR. ESPIRITU | 09/22/2020 OUTLINE Certain solutions can resist drastic changes in pH when I. ACID BASE DEFINITION small quantities of acids and base are added to them. Such A. pH and pOH solutions are called BUFFERS. B. WEAK ACIDS AND BASES Mixtures of a weak acid and a salt containing its C. BUFFERS conjugate base or a weak base and a salt II. BLOOD GAS ANALYSIS containing its conjugate acid. A. COMPONENTS OF ACID BASE STATUS B. ACID BASE MARKERS C. ACID BASE REGULATION III. RESPIRATORY AND METABOLIC DISORDERS IV. ABG ANALYSIS V. ACID-BASE COMPENSATION VI. RESPIRATORY ACIDOSIS VII. RESPIRATORY ALKALOSIS VIII. METABOLIC ACIDOSIS IX. METABOLIC ALKALOSIS I. ACID BASE DEFINITION ARRHENIUS - acids are substances that increase the concentration of hydronium ions when added to solutions - base increases the concentration of hydroxide ions. BRONSTED-LOWRY - Bronsted-Lowry acid is a substance that donates a proton (hydrogen ion) - Bronsted-Lowry base is a substance that accepts a proton Important buffer: aluminum hydroxide and magnesium hydroxide – drugs that are used as antacid LEWIS - Lewis acid is a substance that accepts an electron pair ACID-BASE BALANCE - Lewis base is a substance that donates an unshared The body is designed for optimum performance at a specific pH level electron pair Cell division Metabolic processes A. pH AND pOH structures of biomolecules will be denatured if subjected to Because of the enormous range in the concentrations of hydronium extreme pH – they won’t be able to participate to different and hydroxide ions, we usually use a logarithmic scale to express metabolic processes this concentrations: II. BLOOD GAS ANALYSIS Important diagnostic tool to determine: 1. Acid-base balance 2. Oxygenation status 3. Abnormalities in respiration and kidney function B. WEAK ACIDS AND BASES Weak acid and bases – do not readily dissociate to its ionic components Strong acids and bases – readily dissociate into its ionic components The dissociation constant for a weak acid is K= [H+ ] [A ]/[HA] The Henderson-Hasselbalch equation was derived from the equation for the dissociation constant of a weak acid or base: pH = pK + log 10 [A ]/[HA] C. BUFFERS PREPARED AND EDITED BY: TRANS GROUP 2  (002) ARTERIAL BLOOD GAS INTERPRETATION DR. ESPIRITU | 09/22/2020 A. COMPONENTS OF ACID-BASE STATUS IV. ABG ANALYSIS pH- measures the bloods acidity pH pCO2 HCO3 Normal range 7.35- 7.45 Respiratory A (45) factors Respiratory A (>7.35) B N (22-26) pCO2- partial pressure of carbon dioxide in the blood Alkalosis (