Measure Abbreviation
Data Collection Method

This measure is calculated based on data extracted from the electronic medical record combined with administrative data sources such as professional fee and discharge diagnoses data. This measure is explicitly not based on provider self-attestation.

Measure Type

Percentage of cases where intraoperative hypotension (MAP < 55 mmHg) was sustained for less than 20 minutes.

Measure Time Period

Intraoperative. See ‘Other Measure Build Details’ for more information


All patients requiring general anesthesia or monitored anesthesia care (MAC).

  • Patients < 18 years old
  • ASA 5 and 6 cases
  • Baseline MAP < 60 mmHG (Highest MAP documented in preop under MPOG concepts 71120, 70211, 70212)
  • Obstetric Non-Operative Procedures (CPT: 01958)
  • Labor Epidurals as determined by the MPOG 'Obsteric Anesthesia Type' phenotype results 'Labor Epidural' and 'Conversion (Labor Epidural Portion)'
  • Obstetric Non-Operative Procedures with procedure text: “Labor Epidural”
  • Cardiac Cases as determined by the MPOG Procedure Type: Cardiac phenotype to be 'Open' or 'Other' cardiac case
  • Liver Transplants (see ProcedureTypeTransplantLiver phenotype)
  • Lung Transplants (see ProcedureTypeTransplantLung phenotype)
  • Cases where the ‘Measure End Time’ precedes ‘Measure Start Time’ will be excluded and marked 'invalid'


  • MAP <55mmHG that does not exceed cumulative time of 20 minutes OR
  • MAP >55mmHG throughout case length.
Other Measure Build Details
  • BP 01 measures the cumulative time of Mean Arterial Pressure (MAP) <55mmHG for a given case and provider. BP 01 includes non-invasive and invasive blood pressure monitoring captured using automated and manually entered physiologic data.
  • Instances where there are two blood pressure monitoring methods, the higher MAP will be used to determine measure compliance. 
  • Artifact readings will be identified and removed from final measurement calculation. Artifact processing: if systolic and diastolic blood pressures are present, the values must be at least 5 mmHg apart; otherwise the values will be excluded. MAP values less than 10 are excluded.
  • Each incidence of MAP <55 will attribute the responsible provider for a max of 5 minutes
  • To determine how many minutes the last BP documented accounts for, the difference between it the “Measure End Time” algorithm is used (see page 3). As with the duration of other BPs, this duration is also capped at 5 minutes.

Algorithm for determining Measure Start/End Times:


Measure Start Time:

First Blood Pressure Reading after the latest of these 3 times:

  1. First documented Anesthesia Start time.
  2. First documented Patient in Room time.
  3. First documented Data Capture Start time.

* For labor epidurals which convert to cesarean deliveries where the procedures are combined under one case ID, 'Cesarean Delivery Start Time' is used as the 'Measure Start Time'

Measure End Time:

  1. Patient Out of Room. If not available,
  2. Data Capture End. If not available,
  3. Anesthesia End.

* For labor epidurals which convert to cesarean deliveries where the procedures are combined under one case ID, the latest 'data capture end' is used as the 'Measure End Time' when appropriate (all other cases use logic from 'Data Capture End' phenotype)

Responsible Provider

All providers for a given case whose individual cumulative MAP < 55mmHG exceeds the 20 minute timeframe

MPOG Concept IDs Required


BP Sys Invasive Unspecified Site 1


BP Mean Arterial Line (Invasive, Peripheral)


BP Dias Invasive Unspecified Site 1


BP Sys Invasive Unspecified Site 2


BP Mean Invasive Unspecified Site 1


BP Dias Invasive Unspecified Site 2


BP Sys Non-invasive


BP Mean Invasive Unspecified Site 2


BP Dias Non-invasive


BP Sys Invasive Unspecified Site 3


BP Mean Non-invasive


BP Dias Invasive Unspecified Site 3


BP Sys Invasive Unspecified Site 4


BP Mean Invasive Unspecified Site 3


BP Dias Invasive Unspecified Site 4


BP Sys Invasive Unspecified Site 5


BP Mean Invasive Unspecified Site 4


BP Dias Invasive Unspecified Site 5


BP Sys Arterial Line (Invasive, Peripheral)


BP Mean Invasive Unspecified Site 5


BP Dias Arterial Line (Invasive, Peripheral)


BP Sys Invasive Unspecified Site 2

Data Diagnostics Affected
  • Percentage of Physiologic Observations with a Meaningful Type Mapping
  • Percentage of Cases with Invasive Blood Pressure
  • Percentage of Cases with Non-invasive Blood Pressure
  • Percentage of Cases with Physiologic Observations
  • Percentage of Physiologic Rows that are Machine Captured
  • Percentage of Cases with any Staff Tracking
  • Percentage of Anesthesia Provider Sign-Ins that are Timed

Intraoperative hypotension is associated with compromised organ perfusion and puts patients at risk for post-operative mortality, cardiac adverse events (CAEs), acute kidney injury, and stroke. Multiple studies have demonstrated the association of a decreased mean arterial pressure and postoperative morbidity and mortality. One retrospective review included 33,000 non-cardiac surgical patients and determined that a mean arterial pressure less than 55mmHG predicted CAEs and adverse renal-related outcomes6. This was confirmed by a distinct investigation of 5000 patients using invasive blood pressure measurement5.

Risk Adjustment

Not Applicable

  1. Bijker JB, Persoon S, Peelen LM, Moons KG, Kalkman CJ, Kappelle LJ, van Klei WA. Intraoperative hypotension and perioperative ischemic stroke after general surgery: a nested case-control study.
  2. Anesthesiology. 2012 Mar 116(3): 658-64. doi: 10.1097/ALN.0b013e3182472320. PMID: 22277949
  3. Bijker JB, van Klei WA, Vergouwe Y, Eleveld DJ, van Wolfswinkel L, Moons KG, Kalkman CJ. Intraoperative hypotension and 1-year mortality after noncardiac surgery.
  4. Anesthesiology. 2009 Dec 111(6): 1217-26. doi: 10.1097/ALN.0b013e3181c14930. PMID: 19934864
  5. Sun LY, Wijeysundera DN, Tait GA, Beattie WS. Association of Intraoperative Hypotension with Acute Kidney Injury after Elective Noncardiac Surgery Anesthesiology. 2015 Sep123(3): 515-23. doi: 10.1097/ALN.0000000000000765. PMID: 26181335
  6. Walsh M, Devereaux PJ, Garg AX, Kurz A, Turan A, Rodseth RN et al. Relationship between intraoperative mean arterial pressure and clinical outcomes after noncardiac surgery: Toward an empirical definition of hypotension. Anesthesiology 2013; 119:507-515. Doi: 10.1097/ALN.0b013e318a10e26. PMID: 23835589.