ICD-10 · PDGM grouping
W94 Exposure to high and low air pressure and changes in air pressure
All 30 codes in the W94 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
ICD-10-CM FY2027 · CMS grouper v07.2.26
Codes in family
30
Can lead a claim
0
Cannot lead a claim
30
What CMS assigns to W94
None of the 30 codes is assigned a clinical group. None of the 30 is assigned a comorbidity subgroup. None can lead a claim.
Every code in W94
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| W94.0 Exposure to prolonged high air pressure | ||||
| W94.0XXA | Exposure to prolonged high air pressure, initial encounter | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.0XXD | Exposure to prolonged high air pressure, subsequent encounterCMS: Exposure to prolonged high air pressure, subs encntr | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.0XXS | Exposure to prolonged high air pressure, sequela | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.1 Exposure to prolonged low air pressure | ||||
| W94.11 Exposure to residence or prolonged visit at high altitude | ||||
| W94.11XA | Exposure to residence or prolonged visit at high altitude, initial encounterCMS: Expsr to resdnce or prolonged visit at high altitude, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.11XD | Exposure to residence or prolonged visit at high altitude, subsequent encounterCMS: Expsr to resdnce or prolonged visit at high altitude, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.11XS | Exposure to residence or prolonged visit at high altitude, sequelaCMS: Expsr to resdnce or prolonged visit at high altitude, sqla | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.12 Exposure to other prolonged low air pressure | ||||
| W94.12XA | Exposure to other prolonged low air pressure, initial encounterCMS: Exposure to other prolonged low air pressure, init encntr | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.12XD | Exposure to other prolonged low air pressure, subsequent encounterCMS: Exposure to other prolonged low air pressure, subs encntr | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.12XS | Exposure to other prolonged low air pressure, sequela | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.2 Exposure to rapid changes in air pressure during ascent | ||||
| W94.21 Exposure to reduction in atmospheric pressure while surfacing from deep-water diving | ||||
| W94.21XA | Exposure to reduction in atmospheric pressure while surfacing from deep-water diving, initial encounterCMS: Expsr to rdct in atmos pressr wh surfc fr dp-watr div, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.21XD | Exposure to reduction in atmospheric pressure while surfacing from deep-water diving, subsequent encounterCMS: Expsr to rdct in atmos pressr wh surfc fr dp-watr div, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.21XS | Exposure to reduction in atmospheric pressure while surfacing from deep-water diving, sequelaCMS: Expsr to rdct in atmos pressr wh surfc fr dp-watr div, sqla | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.22 Exposure to reduction in atmospheric pressure while surfacing from underground | ||||
| W94.22XA | Exposure to reduction in atmospheric pressure while surfacing from underground, initial encounterCMS: Expsr to rdct in atmos pressr wh surfc fr underground, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.22XD | Exposure to reduction in atmospheric pressure while surfacing from underground, subsequent encounterCMS: Expsr to rdct in atmos pressr wh surfc fr underground, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.22XS | Exposure to reduction in atmospheric pressure while surfacing from underground, sequelaCMS: Expsr to rdct in atmos pressr wh surfc fr underground, sqla | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.23 Exposure to sudden change in air pressure in aircraft during ascent | ||||
| W94.23XA | Exposure to sudden change in air pressure in aircraft during ascent, initial encounterCMS: Expsr to chng in air pressure in arcrft during ascent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.23XD | Exposure to sudden change in air pressure in aircraft during ascent, subsequent encounterCMS: Expsr to chng in air pressure in arcrft during ascent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.23XS | Exposure to sudden change in air pressure in aircraft during ascent, sequelaCMS: Expsr to chng in air pressr in arcrft during ascent, sequela | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.29 Exposure to other rapid changes in air pressure during ascent | ||||
| W94.29XA | Exposure to other rapid changes in air pressure during ascent, initial encounterCMS: Expsr to oth rapid changes in air pressr during ascent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.29XD | Exposure to other rapid changes in air pressure during ascent, subsequent encounterCMS: Expsr to oth rapid changes in air pressr during ascent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.29XS | Exposure to other rapid changes in air pressure during ascent, sequelaCMS: Expsr to oth rapid changes in air pressr during ascent, sqla | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.3 Exposure to rapid changes in air pressure during descent | ||||
| W94.31 Exposure to sudden change in air pressure in aircraft during descent | ||||
| W94.31XA | Exposure to sudden change in air pressure in aircraft during descent, initial encounterCMS: Expsr to chng in air pressure in arcrft during descent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.31XD | Exposure to sudden change in air pressure in aircraft during descent, subsequent encounterCMS: Expsr to chng in air pressure in arcrft during descent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.31XS | Exposure to sudden change in air pressure in aircraft during descent, sequelaCMS: Expsr to chng in air pressr in arcrft during descent, sqla | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.32 Exposure to high air pressure from rapid descent in water | ||||
| W94.32XA | Exposure to high air pressure from rapid descent in water, initial encounterCMS: Expsr to high air pressure from rapid descent in water, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.32XD | Exposure to high air pressure from rapid descent in water, subsequent encounterCMS: Expsr to high air pressure from rapid descent in water, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.32XS | Exposure to high air pressure from rapid descent in water, sequelaCMS: Expsr to high air pressr from rapid descent in water, sqla | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.39 Exposure to other rapid changes in air pressure during descent | ||||
| W94.39XA | Exposure to other rapid changes in air pressure during descent, initial encounterCMS: Expsr to oth rapid changes in air pressr dur descent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.39XD | Exposure to other rapid changes in air pressure during descent, subsequent encounterCMS: Expsr to oth rapid changes in air pressr dur descent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| W94.39XS | Exposure to other rapid changes in air pressure during descent, sequelaCMS: Expsr to oth rapid changes in air pressr dur descent, sqla | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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