The Measurement of Urinary Ammonium as an Indicator for Smoking Effect on Acid Base Balance

Respiratory acidosis occurs when the gas exchange between oxygen and carbon dioxide in the lungs is not sufficient. Chronic obstructive pulmonary disease (COPD) which is a general group of diseases, including smoking,that causes respiratory acidosis. The study included 50 smokers and 20 healthy individuals as a control, all of the smokers are: non diabetic, non obese, normal heart and kidneys and no administration of analgesics. The excretion of ammonium in urine and its measurement is a good parameter to quantify acid excretion of kidneys, the excretion of acid is increased when the acidity of blood is increased due to respiratory problems which is the compensation mechanism between lungs and kidneys. They study results showed an increase in urinary ammonium concentration (48.18±1.15 µM) for smokers compared with control group. The high levels of urinary ammonium ions for smokers means that gas exchange is affected by smoking which leads to an increase in CO₂ causing an increase in hydrogen ion concentration [H⁺] which is respiratory acidosis. In this case the kidneys compensate the lungs by excretion more hydrogen ions in combination with ammonia derived from glutamic acid as ammonium ions to restore normal pH. Therefore we can use the concentration of urinary ammonium as an indicator for respiratory acidosis induced by smoking.