Respiratory Acidosis (RA) or Acute Respiratory Distress Syndrome (ARDS) is a condition characterized by symptoms such as shortness of breath, chest pain, cough, wheezing and other signs and symptoms indicating the presence of carbon dioxide in the blood.  RA is caused by excessive production of CO2 in the body due to various causes like: exercise, smoking cigarettes, being overweight and alcohol consumption. 
The main cause of RA is the increase in the concentration of carbonic acid in the blood. Carbonic acid is produced when there are excess amounts of H+ ions in the blood. When there are too many H+ ions present, they will bind with calcium and magnesium ions located in cells causing them to become less conductive. This leads to a decrease in their ability to carry electrical charges. The result is increased resistance in the heart, lungs and other organs.
Acidosis occurs when there is a reduction in the amount of hydrogen ion available to carry out its job. Hydrogen ions are neutralized by carbonate ions (HCO 3 -). These carbonate ions are normally found in the stomach and intestines but can also be generated from dietary sources like fruits, vegetables, milk products etc. When there is a decrease in the amount of H+ and increase in the amount of HCO3 -, it is referred to as “Respiratory”. This is also known as respiratory alkalosis.
Acid-base disturbances are conditions where there is a disturbance in the normal concentration of acids and bases in your blood. Acids can be thought of as things that “release H+”, and bases are things that “release OH-“. The concentration of these ions in your blood are very important to maintain a constant pH; if they get too high or too low, it can cause life-threatening conditions.
In the case of respiratory acidosis, there is a decrease in the amount of bicarbonate (HCO 3 -) available to neutralize hydrogen (H+) ions. This results in a condition where the blood becomes too acidic. The most common causes of this condition are asthma, emphysema and pneumonia. These diseases impair the patient’s ability to respire, and as a result, they suffer from an irregular heartbeat, difficulty breathing and shortness of breath.
One of the most effective methods of treating this condition is through administration of intravenous fluids. The fluids work to improve the patient’s ability to respire by delivering needed electrolytes and bicarbonate directly into the blood stream.
There are also conditions such as central sleep apnea, obesity and heart failure that can cause respiratory acidosis. Central sleep apnea is a sleep disorder where the patient stops breathing for short periods of time, usually lasting between one and two minutes.
Sources & references used in this article:
Respiratory acidosis. by SK Epstein, N Singh – Respiratory care, 2001 – ncbi.nlm.nih.gov
Helium-oxygen mixtures in intubated patients with status asthmaticus and respiratory acidosis by EH Gluck, DJ Onorato, R Castriotta – Chest, 1990 – Elsevier
The renal response to acute respiratory acidosis by PJ Dorman, WJ Sullivan, RF Pitts – The Journal of clinical …, 1954 – Am Soc Clin Investig
One year period prevalence study of respiratory acidosis in acute exacerbations of COPD: implications for the provision of non-invasive ventilation and oxygen … by PK Plant, JL Owen, MW Elliott – Thorax, 2000 – thorax.bmj.com