Respiratory acidosis: Difference between revisions
Neil.m.young (talk | contribs) (Text replacement - "==Treatment==" to "==Management==") |
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*[[COPD]] | *[[COPD]] | ||
*Drugs ([[Opioid Overdose]]) | *Drugs ([[Opioid Overdose]]) | ||
*Chest wall | *Chest wall disease | ||
*Pleural | *Pleural disease | ||
*Trauma | *Trauma | ||
Revision as of 07:32, 13 July 2016
Background
- acidemia = pH < 7.38
- respiratory acidosis = pCO2 > 42
- Acute respiratory acidosis: Change in pH = 0.008 X (40 - PaCO2)
vs. Chronic respiratory acidosis: Change in pH = 0.003 X (40 - PaCO2)
- determine if another primary acid/base disturbance is occurring
- calculate AG
- if HCO3 < 24 + (pCO2-40)/10 x 3(+/-1) then there is a superimposed primary metabolic acidosis
- for every 10mm increase in pCO2 >40, HCO3expected increases by 2-4mEq (2 if acute/limited time for metabolic compensation, 4 if chronic i.e. COPD)
- if HCO3 > 24 + (pCO2-40)/10 x 3(+/-1) then suspect primary metabolic alkalosis
Etiology
Hypoventilation - acute vs chronic
Differential Diagnosis
- COPD
- Drugs (Opioid Overdose)
- Chest wall disease
- Pleural disease
- Trauma
Diagnosis
Management
Improve alveolar ventilation
- Bronchodilators
- CPAP
- Intubation (esp of pH < 7.25)
- Do not reduce pH too quickly (>5Hg/h)
- Can lead to abrupt Hypocalcemia/Hypokalemia
- Do not reduce pH too quickly (>5Hg/h)