AaDO2: Difference between revisions
Ttenbergen (talk | contribs) m scoring info should be only in the scoring article, will integrate into the heading there... |
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{{Data_element | |||
| field_name = Ap_K | |||
| element_description = The patient's {{#show: K | ?AP phys name}} level in {{#show: K | ?AP phys unit}}. | |||
| CCMDB_label = K | |||
| CCMDB_tab = Apache | |||
| in_table = L_Log | |||
| data_type = number | |||
| datafield_length = single | |||
| program_collecting = CC | |||
| created_raw = Raw | |||
| data_element_sort_index = 73 | |||
}} | |||
'''AaDO2 - Alveolar-arterial oxygen tension difference | '''AaDO2 - Alveolar-arterial oxygen tension difference | ||
''' | ''' | ||
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See [[APACHE_Scoring_table#.2A2_-_Arterial_Blood_Gas_.28ABG.29_scoring]] for how AaDO2 is used to generate the APACHE score. | See [[APACHE_Scoring_table#.2A2_-_Arterial_Blood_Gas_.28ABG.29_scoring]] for how AaDO2 is used to generate the APACHE score. | ||
{{APACHE physiological variable | |||
|AP phys name= Alveolar-arterial oxygen tension difference | |||
|AP phys unit= | |||
|AP H4= >500 | |||
|AP H3= >=350 and <500 | |||
|AP H2= >=200 and <350 | |||
|AP 0= <200 | |||
}} | |||
=== Why the constant 713? === | === Why the constant 713? === | ||
Revision as of 02:03, 8 January 2017
| Data Element (edit) | |
| Field Name: | Ap_K |
| CCMDB Label: | K |
| CCMDB tab: | Apache |
| Table: | L_Log |
| Data type: | number |
| Length: | single |
| Program: | CC |
| Created/Raw: | Raw |
| Start Date: | 1988-07-11 |
| End Date: | 2300-01-01 |
| Sort Index: | 73 |
| Data Dependencies(Reports/Indicators/Data Elements): | |
The patient's Potassium level in mmol/L.
AaDO2 - Alveolar-arterial oxygen tension difference
Measures the difference in the partial pressure of oxygen between the alveoli and the arteries. This measures the efficiency of the oxygen exchange between the lung alveoli and the pulmonary capillaries.
- A calculated component of APACHE II score when FIO2 being administered to a patient is >=50%.
See APACHE_Scoring_table#.2A2_-_Arterial_Blood_Gas_.28ABG.29_scoring for how AaDO2 is used to generate the APACHE score.
| Apache Physiological Variable | |
| variable name | Alveolar-arterial oxygen tension difference |
| unit | |
| absolute max allowed | |
| warning max | |
| high score 4 | >500 |
| high score 3 | >=350 and <500 |
| high score 2 | >=200 and <350 |
| high score 1 | |
| score 0 | <200 |
| low score 1 | |
| low score 2 | |
| low score 3 | |
| low score 4 | |
| AP phys warnMin | |
| AP phys absMin | |
APACHE Score
This value is used to generate the APACHE Score.
Collecting Apache physiological variables
There are some specific rules to follow in choosing which one of several lab results to collect.
See APACHE physiological variable collection for details.
Cross Chcks
Rules described in APACHE_physiological_variable_collection#Exceptionally_high_or_low_values are implemented by Check APACHE physiological variable high low.
Why the constant 713?
The value 713 mmHg is the barometric pressure (Pb) used in the AaDO2 formula.
Normal Sea level Pb is 760 mmHg. (Winnipeg is close to sea level. We don't adjust for different elevations around the city nor do we adjust this value for the constant changes in Pb).
The barometric pressure is corrected for water vapor pressure (Pbc).
- (vapor pressure is 47 mmHg @ a temperature of 37C).
- (760-47)= Pbc of 713 mmHg.