Percentage of high cardiac risk cases with significantly elevated postoperative troponin levels.

Preventing myocardial infarction is an important anesthetic goal. Protecting against this outcome is particularly relevant among patients with comorbid conditions or undergoing surgeries at high risk of major adverse cardiac events.

Troponin I levels are accurate markers of myocardial infarction. Postoperative myocardial injury within 72 hours (as defined by a Troponin I level >2x the 99th percentile upper reference limit) is associated with a significantly increased risk of 30-day mortality. Furthermore, any amount of postoperative myocardial injury (as defined by a Troponin I level > 0.03 ng/mL) is an independent predictor of 30-day mortality.  Adjusted relative risk of death was 4.2 for patients with Troponin I ≥ 0.60 ng/mL.

Anesthesia End to 72 hours after Anesthesia End

• All high-risk surgeries^* OR
• All anesthetic cases performed on patients with history of ischemic heart disease, congestive heart failure, cerebrovascular disease, diabetes requiring preoperative insulin, or chronic kidney disease (baseline Cr > 2.0 mg/dL).^**

* High-risk surgeries include intraperitoneal, intrathoracic, or suprainguinal vascular procedures, as adapted from the Revised Cardiac Risk Index (RCRI) and identified by Anesthesia CPT codes:

** Comorbidities posing high cardiac risk are adapted from the Revised Cardiac Risk Index (RCRI) and are identified by Elixhauser Comorbidity Index variables (congestive heart failure, diabetes), preoperative lab values (baseline serum creatinine), or comorbidity-specific ICD-9/10 codes (ischemic heart disease, cerebrovascular disease):

• ASA 5 and 6 cases.
• Outpatient cases
• Troponin I > 0.01 ng/mL within 42 days prior to anesthesia start^***
• Cardiac Cases

*** Rationale for excluding patient with troponin elevation within 42 days prior to date of surgery is based upon ACC/AHA guidelines recommending a delay in elective surgery for 6 weeks following myocardial infarction.

In cases with Troponin I or Troponin T value(s) available within 72 hours after anesthesia end, all values must be less than or equal to the following:

• Troponin I (ctnl) ≤ 600 ng/L
• Troponin I (ctnl) ≤ 0.6 ng/mL
• Troponin T (hs-cTnT) ≤ 84 ng/L
• Troponin T (hs-cTnT) ≤ 84 pg/L
• Troponin T (hs-cTnT) ≤ 0.084 ng/mL

If no Troponin I (or Troponin T) values are available within 72 hours after anesthesia end and there is no documentation of perioperative myocardial injury (MPOG Concepts: 90201, 90202), the case will not be flagged (ie we presume no myocardial injury).

• CARD 03 is an outcome measure that identifies high cardiac risk patients that have severely elevated troponin levels within 72 hours postoperatively.
• If another case starts within 72 hours, then the time window ends at anesthesia start of the subsequent case. 
• For the preoperative Troponin I exclusion, cases with preoperative Troponin I values with ‘less than (<)’ included in the result will be included up to ‘<0.31.’ For example, preoperative Troponin I levels that are resulted as ‘<0.02’ will be included for the measure. However, a preoperative Troponin I value of 0.02 will be excluded. The rationale for this is each pathology department determines the lower bound for detecting Troponin I levels accurately. This is standardized to the health system but is not standard across all participating sites. 
• For sites that use high sensitivity troponin T, although kinetics are different for Trop T and Trop I, a hs-Trop T measurement of 30 pg/ml roughly correlates with the initial detectable level of Trop I (just above 0.1 ng/ml). An hs-Trop T of 140 pg/ml roughly correlates with a current Trop I value of 1.0 ng/ml.  Using those endpoints, a Trop I value of .6 ng/ml roughly correlates to a hs-Trop T of .84 pg/ml.

Algorithm for determining Provider Sign-In Duration

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

To evaluate provider-level risk adjustment we will calculate the observed to expected outcomes ratio (O/E). The O/E is calculated using a logistic regression model and predicts (given a set list of dependent patient and hospital level variables) the expected probability of having an elevated Troponin I level. We adjust for surgery risk score, emergent procedures, ASA, gender, age, body mass index, laboratory values, and teaching versus private hospital. Patient specific comorbidities are evaluated as well.

Primary Provider - Provider(s) present for longest duration of the case per staff role, unless there are providers who failed BP-01 (sustained MAP < 55 mmHg) during case. If true, BP-01 flag takes precedence over longest duration.

Method for determining Responsible Provider:

1. Provider(s) who failed BP 01. If not applicable,
2. Provider(s) present for longest duration of the case per staff role. 

1. Thygesen K, Alpert JS, Jaffe AS, Simoons ML, Chaitman BR, White HD. Third universal definition of myocardial infarction. Global Heart. 2012;7(4):275-295.
2. Devereaux PJ, Xavier D, Pogue J, et al. Characteristics and short-term prognosis of perioperative myocardial infarction in patients undergoing noncardiac surgery: a cohort study. Annals of internal medicine. 2011;154(8):523-528.
3. Botto F, Alonso-Coello P, Chan MT, et al. Myocardial injury after noncardiac surgery: a large, international, prospective cohort study establishing diagnostic criteria, characteristics, predictors, and 30-day outcomes. Anesthesiology. 2014;120(3):564-578.
4. Fleisher LA, Fleischmann KE, Auerbach AD, et al. 2014 ACC/AHA guideline on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery. Journal of nuclear cardiology: official publication of the American Society of Nuclear Cardiology. 2015;22(1):162-215.
5. Abbott TEF, Pearse RM, Archbold RA, et al. A Prospective International Multicentre Cohort Study of Intraoperative Heart Rate and Systolic Blood Pressure and Myocardial Injury After Noncardiac Surgery: Results of the VISION Study. Anesth Analg. 2018 Jun;126(6):1936-1945
6. Quan H, Sundararajan V, Halfon P, et al. Coding algorithms for defining Comorbidities in ICD-9-CM and ICD-10 administrative data. Med Care. 2005 Nov; 43(11): 1130-9.