The human body maintains a precise pH range of arterial blood between 7.35 and 7.45. Deviations result in either acidosis (pH < 7.35) or alkalosis (pH > 7.45). These conditions are further classified as respiratory or metabolic disorders based on their underlying cause.

Respiratory Acidosis and Alkalosis
Respiratory acidosis occurs due to an increase in the partial pressure of carbon dioxide PCO2 in the blood. It often arises from shallow breathing or impaired gas exchange caused by pneumonia, cystic fibrosis, or emphysema. These conditions lead to CO2accumulation, resulting in a decrease in blood pH.

Respiratory alkalosis, by contrast, is caused by a decrease in blood PCO2 ​​ below 35 mmHg, typically due to hyperventilation. Common triggers include oxygen deficiency, stroke, or severe anxiety. This reduction in PCO2 causes an increase in blood pH, shifting the body into an alkalotic state.

Metabolic Acidosis and Alkalosis
Unlike respiratory disorders, which originate from changes in CO2 levels, metabolic disorders arise due to fluctuations in bicarbonate levels or non-carbonic acids. Metabolic acidosis is characterized by decreased blood bicarbonate ion (HCO3⁻) levels below 22 mEq/L. This condition may result from:

  1. Loss of HCO₃⁻ through diarrhea or renal dysfunction
  2. Accumulation of non-carbonic acids such as lactic acid or ketones
  3. Impaired kidney function leading to reduced excretion of hydrogen ions (H⁺)

These factors contribute to a drop in blood pH.

Metabolic alkalosis occurs when blood HCO3⁻ levels rise above 26 mEq/L, causing a corresponding increase in blood pH above 7.45. This condition often results from:

  1. Non-respiratory acid loss due to excessive vomiting or gastric suctioning
  2. Overconsumption of antacids or alkaline drugs
  3. Endocrine disorders, diuretics, or severe dehydration

Respiratory and metabolic acid-base disorders can disrupt homeostasis and require prompt intervention to restore pH balance. If left untreated, these disorders may lead to severe physiological complications. Prompt intervention is critical to restoring pH balance.

Из главы 30:

article

Now Playing

30.18 : Disorders of Acid-Base Balance

Fluid, Electrolyte, and Acid-Base Balance

59 Просмотры

article

30.1 : Содержание воды в организме и отсеки для жидкости

Fluid, Electrolyte, and Acid-Base Balance

197 Просмотры

article

30.2 : Состав жидкостей организма

Fluid, Electrolyte, and Acid-Base Balance

148 Просмотры

article

30.3 : Перемещение жидкости между отсеками

Fluid, Electrolyte, and Acid-Base Balance

167 Просмотры

article

30.4 : Регулирование забора воды

Fluid, Electrolyte, and Acid-Base Balance

161 Просмотры

article

30.5 : Регулирование подачи воды

Fluid, Electrolyte, and Acid-Base Balance

109 Просмотры

article

30.6 : Нарушение водного баланса

Fluid, Electrolyte, and Acid-Base Balance

126 Просмотры

article

30.7 : Роль электролитов: натрия и калия

Fluid, Electrolyte, and Acid-Base Balance

51 Просмотры

article

30.8 : Роль электролитов: хлорида и бикарбоната

Fluid, Electrolyte, and Acid-Base Balance

31 Просмотры

article

30.9 : Роль электролитов: кальция и фосфата

Fluid, Electrolyte, and Acid-Base Balance

41 Просмотры

article

30.10 : Регулирование содержания натрия и калия

Fluid, Electrolyte, and Acid-Base Balance

43 Просмотры

article

30.11 : Кислотно-щелочной баланс

Fluid, Electrolyte, and Acid-Base Balance

113 Просмотры

article

30.12 : Буферные системы в организме

Fluid, Electrolyte, and Acid-Base Balance

143 Просмотры

article

30.13 : Белковые буферы в плазме крови и клетках

Fluid, Electrolyte, and Acid-Base Balance

137 Просмотры

article

30.14 : Фосфатный буфер

Fluid, Electrolyte, and Acid-Base Balance

113 Просмотры

See More

JoVE Logo

Исследования

Образование

О JoVE

Авторские права © 2025 MyJoVE Corporation. Все права защищены