This phenotype returns the minutes of tidal volume documented intraoperatively. Case start and end are determined by the following algorithm:

• Case Start
  • Patient In Room. If not available, then
  • Induction End. If not available, then
  • Anesthesia Start
• Case End
  • Patient out of room. If not available, then
  • Anesthesia End

Step 1. Evaluate set tidal volume recordings as determined by the 'Tidal Volume Set' phenotype

• Calculate the difference in seconds between recordings (capped at 60)
• Sum the difference totals
• Divide by 60 to return the total minutes of set tidal volume

Step 2. Separately, evaluate the actual tidal volume recordings as determined by the 'Tidal Volume Actual' phenotype

• Calculate the difference in seconds between recordings (capped at 60)
• Sum the difference totals
• Divide by 60 to return the total minutes of actual tidal volume

Step 3. Determine which minute total to return using the following priority list:

• If actual duration is = 45 minutes, use actual
• If set duration is = 45 minutes, use set
• If actual duration is longer than set duration, use actual
• Otherwise, use set duration
• Return 0 if no duration is found for either