Arterial Blood Gas (ABG) Lab Values and Imbalances

This flashcard set covers the essential lab values, normal ranges, and clinical causes related to Arterial Blood Gas (ABG) analysis as discussed in the lecture.

ABG

Stands for arterial blood gases, a set of lab values collected from arterial lines to assess acid-base imbalances.

Radial artery

The most common site in the wrist used for an arterial line to collect ABG samples.

pH Normal Range

The normal range for blood pH is $7.35$ to $7.45$.

Acidosis

An imbalance characterized by a blood pH lower than $7.35$.

Alkalosis

An imbalance characterized by a blood pH higher than $7.45$.

Bicarbonate ($HCO_3$)

A metabolic value that acts as a base to increase pH, with a normal range of $22$ to $26$.

Carbon Dioxide ($CO_2$)

A respiratory value that acts as an acid, with a normal range of $35$ to $45$, produced by the respiratory system.

ROME

A mnemonic standing for 'Respiratory is Opposite, Metabolic is Equal,' describing the relationship between pH and the other ABG values.

Respiratory Opposite

The principle that the respiratory value ($CO_2$) and pH move in opposite directions: if $CO_2$ goes up, pH goes down.

Metabolic Equal

The principle that the metabolic value ($HCO_3$) and pH move in the same direction: as $HCO_3$ goes down, pH goes down.

Respiratory Acidosis

An imbalance with high $CO_2$ and low pH, often caused by hypoventilation, opioid toxicity, COPD, or pneumonia.

Respiratory Alkalosis

An imbalance with low $CO_2$ and high pH, often caused by hyperventilation (e.g., from anxiety or fever).

Metabolic Acidosis

An imbalance with low $HCO_3$ and low pH, caused by conditions like DKA (diabetic ketoacidosis), diarrhea, or renal failure.

Metabolic Alkalosis

An imbalance with high $HCO_3$ and high pH, caused by factors such as vomiting or the use of diuretics.

Compensation

Occurs when both $CO_2$ and $HCO_3$ values are abnormal because one system is attempting to balance the imbalance caused by the other.

Hypoventilation

A state of decreased breathing where the body retains too much $CO_2$, leading to respiratory acidosis.

Hyperventilation

A state of increased breathing that pushes out too much $CO_2$, leading to respiratory alkalosis.