Hypocarbia
Consequences of hypocarbia
Acute hypocarbia leads to respiratory alkalosis which produces a fall in serum levels of potassium, phosphate (PO4–) and free calcium (Ca2+). With the fall in [H+] that attends hypocarbia potassium migrates intracellularly as the protons leave the cell so that electro-neutrality is maintained. The phosphate ions follow K+. Calcium reduction is secondary to its increased binding to serum albumin and the fall in levels of this cation produces many of the symptoms present in persons with respiratory alkalosis. Hyponatraemia and hypochloremia may also be present occurring in a similar fashion to K+ and PO4–.
The frequent cause of hypocarbia is hyperventilation which may be due to varying causes.
|
Central nervous system |
Hypoxia |
Drugs |
Endocrine |
Pulmonary |
Miscellaneous |
|
Pain |
High altitude |
Progesterone |
Pregnancy |
Pneumonia/hemothorax |
Sepsis |
|
Hyperventilation syndrome |
Severe anaemia |
Methyl xanthines |
Hyper-thyroidism |
Pneumonia |
Hepatic failure |
|
Anxiety |
Right-to-left shunts |
Salicylates |
|
Pulmonary oedema |
Mechanical ventilation |
|
Psychosis |
|
Catecholamines |
|
Pulmonary embolism |
Heat exhaustion |
|
Fever |
|
Nicotine |
|
Aspiration |
Recovery phase of metabolic acidosis |
|
CVA |
|
|
|
Interstitial lung disease |
CRF |
|
Meningitis |
|
|
|
Asthma |
|
|
Encephalitis |
|
|
|
Emphysema |
|
|
Tumor |
|
|
|
Chronic bronchitis |
|
|
Trauma |
|
|
|
|
|