II. Labs
- See Venous Blood Gas
- Arterial Blood source
III. Interpretation: Conditions invalidating or modifying ABG Results
- Delayed analysis
- Iced Sample maintains values for 1-2 hours
- Un-iced sample quickly becomes invalid
- PaCO2 rises 3-10 mmHg/hour
- PaO2 falls at a rate related to initial value
- pH falls modestly
- Excessive Heparin
- Dilutional effect on results
- Decreases bicarbonate and PaCO2
- Large Air bubbles not expelled from sample
- PaO2 rises 0-30 mmHg
- PaCO2 may fall slightly
-
Fever or Hypothermia
- Machine Temperature approaches 37 C
- Patient Temperature shifts oxyhemoglobin curve
-
Hyperventilation or breath holding (due to anxiety)
- May lead to erroneous lab results
IV. Causes: Primary and Secondary Acid Base Disorders
-
Respiratory Acidosis (pCO2 increases)
- Compensated by Metabolic Alkalosis (HCO3 increases)
-
Respiratory Alkalosis (pCO2 decreases)
- Compensated by Metabolic Acidosis (HCO3 decreases)
-
Metabolic Acidosis (HCO3 decreases)
- Compensated by Respiratory Alkalosis (PCO2 decreases)
-
Metabolic Alkalosis (HCO3 increases)
- Compensated by Respiratory Acidosis (PCO2 increases)
V. Interpretation: pH
- See Calculated PaCO2
- Normal arterial pH = 7.36 to 7.44
- Metabolic Conditions are suggested if
- pH changes in the same direction as pCO2
- pH is abnormal but pCO2 remains unchanged
- Metabolic Conditions related changes in Bicarbonate
- Increase pH by 0.01 (with PaCO2 unchanged)
- Bicarbonate increases 0.67 meq/L
- Decrease pH by 0.01 (with paCO2 unchanged)
- Bicarbonate decreases 0.67 meq/L
- Increase pH by 0.01 (with PaCO2 unchanged)
VI. Interpretation: PaO2 (partial pressure of arterial oxygen)
- See A-a Gradient
- See Arterial Blood Oxygen Content (CaO2)
- Normal PaO2
- Room air at sea level: 80-100 mmHg
- Age Adjusted PaO2 = 100 mmHg – 0.3 * AgeY
- Where AgeY is age in years
- Adjusted for FIO2
- Approximate Normal PaO2 = FIO2 * 5
- Normal PaO2/FiO2 >400 mmHg
-
Hypoxemia
- PaO2 < 50 mmHg
VII. Resources
VIII. References
- Arieff (1993) J Crit Illn 8(2): 224-46 [PubMed]
- Narins (1982) Am J Med 72:496 [PubMed]
- Narins (1980) Medicine 59:161-95 [PubMed]
- Ghosh (2000) Fed Pract p. 23-33
- Rutecki (Dec 1997) Consultant, p. 3067-74
- Rutecki (Jan 1998) Consultant, p. 131-42
Images: Related links to external sites (from Bing)
Related Studies
Definition (MSH) | Measurement of oxygen and carbon dioxide in the blood. |
Concepts | Laboratory Procedure (T059) |
MSH | D001784 |
SnomedCT | 167032005, 144274006, 270009008, 278297009, 167018008 |
CPT | 82805, 82803 |
LNC | MTHU008398 |
English | Analyses, Blood Gas, Analysis, Blood Gas, Blood Gas Analyses, Blood Gas Analysis, Gas Analyses, Blood, Gas Analysis, Blood, Blood gases NOS, BLOOD GAS ANAL, ANAL BLOOD GAS, blood gas analyses (lab test), blood gas analyses, analyse blood gas, Test;blood gas analysis, blood gases, analysis blood gas, blood gas measurement, blood gase, blood gas measurements, Blood gases measurement, Analysis of blood gases, Blood gases NOS (procedure), Gases - blood, Blood gas studies, Blood gases--Analysis, Blood gases, Blood gas analysis, Blood gas levels, BGA - Blood gas analysis, BG - Blood gases, Blood gas analysis (procedure), Blood gas measurement (procedure), Blood gas measurement, blood gas analysis |
Italian | Gas ematici, Gas ematici NAS, Emogasanalisi |
Dutch | bloedgassen NAO, bloedgassen, Analyse, bloedgas-, Bloedgasanalyse |
French | Gaz du sang SAI, Analyse des gaz du sang, Gazométrie, Gaz du sang |
German | Blutgase NNB, Blutgase, Blutgasanalyse |
Portuguese | Gases do sangue NE, Análise de Gases do Sangue Arterial, Gasometria Arterial, Gases sanguíneos, Gasometria |
Spanish | Gasometría NEOM, Blood gases NOS, determinación de gases en sangre, SAI (procedimiento), determinación de gases en sangre, SAI, Gasometría Arterial, análisis de gases en sangre (procedimiento), análisis de gases en sangre, determinación de niveles de gases en sangre, medición de gases en sangre (procedimiento), medición de gases en sangre, Gasometría, Análisis de los Gases de la Sangre |
Japanese | 血液ガス, 血液ガスNOS, ケツエキガス, ケツエキガスNOS, 血液ガス分析 |
Swedish | Blodgasanalys |
Finnish | Verikaasuanalyysi |
Russian | GAZOV KROVI ANALIZ, ГАЗОВ КРОВИ АНАЛИЗ |
Czech | Krevní plyny, Krevní plyny NOS, krevní plyny - analýza, analýza krevních plynů |
Croatian | KRVNI PLINOVI, ANALIZA |
Polish | Gazometria krwi, Analiza gazów krwi |
Hungarian | Vérgázok, Vérgázok k.m.n. |
Norwegian | Blodgassanalyse |
Ontology: Analysis of arterial blood gases and pH (C0150411)
Definition (NCI) | Measures the acidity (pH) and the levels of oxygen, carbon dioxide, and bicarbonate in the blood. |
Concepts | Laboratory Procedure (T059) |
ICD9 | 89.65 |
SnomedCT | 390355006, 389623009, 60170009, 91308007 |
English | Analysis of arterial blood gas (oxygen saturation, pO2, pCO2, CO2, pH); rest only, ABG - Arter blood gas analysis, arterial blood gas panel, arterial blood gas panel (lab test), arterial blood gases (lab test), arterial blood gases, ABG panel, Arterial Blood Gas Measurement, ABG, Analysis of arterial blood gases and pH, Blood Gas Analysis, Blood Gas Measurement, Arterial bld gas measure, arterial blood gas, arterial blood gas analysis, analysis arterial blood gas, arterial blood gase, blood gas arterial, Arterial blood gas analysis (procedure), Blood gases, arterial measurement, ABGs measurement, Gases, arterial measurement, ABG - Arterial blood gas analysis, Arterial blood gas analysis, Arterial blood gases, Analysis of arterial blood gases and pH (procedure), Blood gases, arterial measurement (procedure), Measurement of systemic arterial blood gases |
Spanish | análisis de gases en sangre arterial y PH, Gasometría arterial, medición arterial de gases en sangre (procedimiento), medición arterial de gases en sangre, medición arterial de gases, análisis de gases en sangre arterial y PH (procedimiento), análisis de gases en sangre arterial y pH (procedimiento), análisis de gases en sangre arterial y pH |
Czech | Krevní plyny v arteriální krvi |
Dutch | arteriële bloedgassen |
French | Gaz sanguin artériel |
German | Arterielle Blutgase |
Hungarian | Artériás vérgázok |
Italian | Gas nel sangue arterioso |
Japanese | 動脈血ガス, ドウミャクケツガス |
Portuguese | Gases no sangue arterial |
Ontology: A1BG gene (C1412045)
Concepts | Gene or Genome (T028) |
English | A1B, ALPHA-1-B-GLYCOPROTEIN, GAB, A1BG, ABG, alpha-1-B glycoprotein, A1BG gene |