ABG interpretation with tictactoe PDF

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Summary

Worksheet explaining how to determine ABG's using the tic-tac-toe method...

Description

NRSG 200 ABG Interpretation

Normal Blood Gas Values (Adults at Sea Level) Decreased

Normal

Increased

pH

Acidosis

7.35-7.45

Alkalosis

PaCO2

Alkalosis

35-45

Acidosis

PaO2

Hypoxemia

80-100

HCO3-

Acidosis

22-26

Base Excess

-2-+2

O2

95%

Alkalosis

Rules for ABG Interpretation 1. Draw a Tic-Tac-Toe Grid as follows Acidosis

Normal

Alkalosis

2. Assess the pH. Is it within the normal range, acidotic or alkalotic? Write it in the column that applies. 3. Assess the PaCO2. With a respiratory problem, as pH falls below 7.35, the PaCO2 level should rise. If the pH rises above 7.45, the PaCO2 should fall. If the pH and PaCO2 levels are moving in opposite directions, the problem is primarily respiratory in nature. Since PaCO2 is opposite in nature from pH, reverse the range to 45-35 (acidosis to alkalosis). Write it in the column that applies. 4. Assess the HCO3- . With a metabolic problem, as the pH falls, the HCO3- should also fall,

and as the pH increases, the HCO3- is expected to increase. If these values are moving in the same direction, the problem is primarily metabolic. Write it in the column that applies.

5. Ready to solve: Goal #1 Determine if Acidosis, Normal or Alkalosis.



If pH is under the ACIDOSIS column, it is ACIDOSIS.



If pH is under the ALKALOSIS column, it is ALKALOSIS.



If pH is under the NORMAL column, determine whether the value is leaning towards ACIDOSIS or ALKALOSIS and interpret accordingly. This determines compensation.

Goal #2 Determine if Respiratory or Metabolic 

If pH is under the same column as PaCO2, it is RESPIRATORY.



If pH is under the same column as HCO3, it is METABOLIC.



If pH is under the NORMAL column, determine whether the value is leaning towards ACIDOSIS or ALKALOSIS and interpret accordingly.

Goal #3 Determine if there is compensation 

It is FULLY COMPENSATED if pH is normal.



It is PARTIALLY COMPENSATED if all three (3) values are abnormal.



It is UNCOMPENSATED if PaCO2 or HCO3 is normal and the other is abnormal.

Fully Compensated Respiratory Acidosis

pH Normal, but < 7.40

PaCO2 ↑

HCO3↑

Respiratory Alkalosis

Normal, but > 7.40

↓

↓

Metabolic Acidosis

Normal, but < 7.40

↓

↓

Metabolic Alkalosis

Normal, but > 7.40

↑

↑

Partially Compensated

Respiratory Acidosis

pH ↓

PaCO2 ↑

HCO3↑

Respiratory Alkalosis

↑

↓

↓

Metabolic Acidosis

↓

↓

↓

Metabolic Alkalosis

↑

↑

↑

Respiratory Acidosis

pH ↓

PaCO2 ↑

HCO3Normal

Respiratory Alkalosis

↑

↓

Normal

Metabolic Acidosis

↓

Normal

↓

Metabolic Alkalosis

↑

Normal

↑

Uncompensated...