Page 286 - Saunders Comprehensive Review For NCLEX-RN

waste products of protein metabolism are retained; acids increase, and
bicarbonate is unable to maintain acid-base balance.
▪ Severe diarrhea: Intestinal and pancreatic secretions are normally alkaline;
therefore, excessive loss of base leads to acidosis.

Box 9-4
Causes of Metabolic Alkalosis

▪ Diuretics: The loss of hydrogen ions and chloride from diuresis causes a
compensatory increase in the amount of bicarbonate in the blood.
▪ Excessive vomiting or gastrointestinal suctioning: Leads to an excessive loss of
hydrochloric acid.
▪ Hyperaldosteronism: Increased renal tubular reabsorption of sodium occurs,
with the resultant loss of hydrogen ions.

▪ Ingestion of and/or infusion of excess sodium bicarbonate: Causes an increase in
the amount of base in the blood.
▪ Massive transfusion of whole blood: The citrate anticoagulant used for the
storage of blood is metabolized to bicarbonate.

Table 9-3

Normal Arterial Blood Gas Values

− 3
kPa, Kilopascal; mmol, millimole (10 mole); Paco , partial pressure of carbon dioxide in arterial blood; Pao ,
2
2
partial pressure of oxygen in arterial blood; Pvo , partial pressure of oxygen in venous blood. Note: Because
2
arterial blood gases are influenced by altitude, the value for Pao decreases as altitude increases.
2
Table 9-4

Acid-Base Imbalances: Usual Laboratory Value Changes

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