pH levels and Arterial Blood Gases

Blood pH Normal levels of pH are 0-14 Below 6- acidic Above 7-alkaline Use pH paper to determine acidity or alkalinity These pH levels are used for chemicals, body fluids, such as urine, gastric content

Acids Substances that when dissolved in water will ionize into positively charged hydrogen ions and negatively charged ions of some other element.

Alkali (Bases) Substances that when dissolved in water ionizes into negatively charged hydroxide ions and positively charged ions of metal

Neutralization This is the result when an acid and a base are combined to form a salt and a water. Example: heartburn: give antacids and neutralizes the acid into a salt and a water and the heartburn goes away.

Arterial Blood Arterial Blood gas testing measures the dissolved O2 and CO2 and pH levels in the arterial blood.

Arterial Blood gases The ABG measure the effectiveness of tissue perfusion and when imbalanced several health conditions can occur.

pH The pH reflects the hydrogen ions in the circulating blood. This complex buffering system exists in the respiratory and cardiovascular mechanisms and keeps the systems in balance.

Respiratory The lungs (respiratory) compensate for the imbalance within 2 to 3 hours.

Metabolic The kidneys (metabolic) compensate for the imbalances within 2 to 3 days.

Health problems that will alter ABG results Asthma Pneumonia Emphysema Hypoxia Sepsis (infection) Shock Anesthesia Drug overdose (Aspirin toxicity)

Arterial Blood pH This is a useful indicator to determine acid/base balance within the body. Normal range is 7.35 to 7.45

Intracellular- fluid within the cell Homeostasis Intracellular- fluid within the cell Extracellular-fluid outside the cell

Arterial blood gas (ABG) Arterial samples provide information about the ability of the lungs to regulate acid/base balance through retention or release CO2. Effectiveness of the kidneys maintaining appropriate bicarbonate levels can also be gauged.

pH 7.35 to 7.45 CO2- 35-45 (respiratory) HCO3- 24-28 (metabolic) Application of ABG pH 7.35 to 7.45 CO2- 35-45 (respiratory) HCO3- 24-28 (metabolic) O2 saturation- 80 to100

Look at pH first pH: Above 7.45- alkaline Below 7.35- acid

respiratory CO2 above 45-acid Below 35 alkaline

metabolic HCO3 above 28- alkaline Below 24 acid

Example 24 year old female with drug overdose has following ABG results: pH- 7.5 CO2-40 HCO3- 32 pH elevated, alkaline, HCO3 elevated and alkaline Metabolic alkalosis