Acidosis and Alkalosis
The body attempts to maintain its pH when confronted with acid-base. The compensatory processes are different for respiratory and renal disturbances. It is believed that in simple acid-base disorders, it is the change in pH (and not the change in CO2 or H
- PDF / 393,313 Bytes
- 5 Pages / 439.37 x 666.14 pts Page_size
- 88 Downloads / 175 Views
Acidosis and Alkalosis
Contents 6.1 6.2 6.3 6.4
Compensation ................................................................................................................. Coexistence of Acid Base Disorders............................................................................... Conditions in Which pH Can Be Normal ....................................................................... The Acid Base Map ........................................................................................................
A. Hasan, Handbook of Blood Gas/Acid-Base Interpretation, DOI 10.1007/978-1-4471-4315-4_6, © Springer-Verlag London 2013
166 167 168 169
165
6
166
6.1
6
Acidosis and Alkalosis
Compensation
The body attempts to maintain its pH when confronted with acid-base. The compensatory processes are different for respiratory and renal disturbances. It is believed that in simple acid-base disorders, it is the change in pH (and not the change in CO2 or HCO3) produced by the inciting primary disturbance that is the stimulus for compensation.
Primary metabolic disorder
Primary respiratory disorder
6 Compensation is renal (slow)
Chemical buffering (immediate)
Compensation is respiratory (rapid)
Lennon EJ, Lemann J Jr. pH- is it defensible? Ann Intern Med. 1966;65:1151. McCurdy DK. Mixed metabolic and respiratory acid base disturbances: diagnosis and treatment. Chest. 1972;63:355S.
6.2
167
Coexistence of Acid Base Disorders
6.2
Coexistence of Acid Base Disorders
Frequently, two (sometimes three) acid-base disorders occur simultaneously.
Coexistence of multiple acid base disorders
Other combinations of the four (simple) acid base disorders are possible: Two respiratory disorders cannot coexist: The lungs cannot simultaneously retain and excrete CO2!
Two metabolic disorders can occur together.
One metabolic disorder can occur together with a single respiratory disturbance.
Two metabolic disorders can occur together with a single respiratory disturbance.
McCurdy DK. Mixed metabolic and respiratory acid base disturbances: diagnosis and treatment. Chest. 1972;63:355S. Narins RG, Emmet M. Simple and mixed acid-base disorders: a practical approach. Medicine (Baltimore). 1980;59:161.
6
168
6.3
6
Acidosis and Alkalosis
Conditions in Which pH Can Be Normal
Normal pH is possible under three circumstances: No acid-base disturbance exists
A single acid-base disturbance is being fully compensated
6 At least two acid-base disorders co-exist (a primary acidemia is being balanced out by a primary alkalemia).
CO2 and HCO3– are both in the normal range.
CO2 and HCO3– are both low:
Compensated respiratory alkalosis
Either of the two following disturbances is present:
Compensated metabolic acidosis
CO2 and HCO3– are both high:
Compensated respiratory acidosis
Either of the two following disturbances is present:
Compensated metabolic alkalosis
CO2 and HCO3– are both high
A primary respiratory acidosis + a primary metabolic alkalosis
CO2 and HCO3– are both low
A primary respiratory alkalosi
Data Loading...
