Hospital Harm - Acute Kidney Injury

The proportion of inpatient hospitalizations for patients 18 years of age or older who have an acute kidney injury (stage 2 or greater) that occurred during the encounter. Acute kidney injury (AKI) stage 2 or greater is defined as a substantial increase in serum creatinine value, or by the initiation of kidney dialysis (continuous renal replacement therapy (CRRT), hemodialysis or peritoneal dialysis).

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LOINC(R) copyright 2004-2021 Regenstrief Institute, Inc. This material contains SNOMED Clinical Terms(R) (SNOMED CT[R]) copyright 2004-2021 International Health Terminology Standards Development Organisation. ICD-10 copyright 2021 World Health Organization. All Rights Reserved.

This measure and specifications are subject to further revisions. 
This performance measure is not a clinical guideline and does not establish a standard of medical care, and has not been tested for all potential applications.

THE MEASURES AND SPECIFICATIONS ARE PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. 

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Sex and Age

First vital signs since the encounter start:
 - Temperature
 - Heart Rate
 - Respiratory Rate
 - Systolic Blood Pressure 

The estimated glomerular filtration rate (eGFR) calculated using the index serum creatinine, patient sex, and age-based formula

All encounter diagnoses along with their present on admission (POA) indicators are being collected for the development of baseline risk adjustment model. Targeted diagnoses at the time of development include: 
 - Cancer (leukemia, lymphoma, or metastatic cancer)
 - Diabetes
 - Heart failure
 - Hypertension
 - Obesity

Encounter length of stay

For a detailed description of the baseline risk adjustment model and the functional form of risk factors, see the Risk Adjustment Methodology Report here: (TBD)

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This measure focuses on stage 2 or greater acute kidney injury as an outcome in the hospital inpatient setting. Acute kidney injury affects up to 10% of hospitalized patients (Wilson et al., 2015)(Chertow 2005), comparable to the rates of severe sepsis (Hoste, Schurgers, 2008) and acute lung injury (Wilson et al., 2015)(Goldstein et al., 2016)(McCoy et al., 2010). Less severe acute kidney injury and acute kidney injury requiring dialysis affects approximately 2,000 to 3,000 and 200 to 300 per million population per year, respectively. Up to two thirds of intensive care patients will develop acute kidney injury. Acute kidney injury may result in the need for dialysis, and is associated with an increased risk of mortality (Wilson et al., 2013). 

While not all instances of acute kidney injury are avoidable and may be due to natural progression of underlying illness or a complication of a necessary treatment such as chemotherapy, a proportion of acute kidney injury cases are preventable and treatable. The Kidney Disease: Improving Global Outcomes (KDIGO) guidelines suggest careful management of hemodynamic status, fluids, and vasoactive medications for the prevention of acute kidney injury (Wilson et al, 2015). Several studies identified through systematic literature searches developed or evaluated the effectiveness of acute kidney injury electronic alert systems (Selby et al., 2012; Ahmed et al., 2015; Porter et al., 2014; Wilson et al., 2014; Kirkendall et al., 2014; Cho et al., 2012). These studies used data elements for defining acute kidney injury that were already present and populated in the EHR. For acute kidney injury diagnosis, all except two were limited to using serum creatinine levels, suggesting that this is the most reliable and consistently available electronic data element for defining acute kidney injury.

Serum creatinine is an accepted proxy for acute kidney disease (KDIGO 2012). It is cited by many guidelines for defining and monitoring acute kidney injury (Lopes, Jorge 2013)(KDIGO 2012).

The KDIGO offers clinical practice guidelines for preventing and managing acute kidney injury:

FLUIDS
3.1.1: In the absence of hemorrhagic shock, we suggest using isotonic crystalloids rather than colloids (albumin or starches) as initial management for expansion of intravascular volume in patients at risk for acute kidney injury or with acute kidney injury.

VASOPRESSORS
3.1.2: We recommend the use of vasopressors in conjunction with fluids in patients with vasomotor shock with, or at risk for, acute kidney injury. 

PROTOCOLIZED HEMODYNAMIC MANAGEMENT
3.1.3: We suggest using protocol-based management of hemodynamic and oxygenation parameters to prevent development or worsening of acute kidney injury in high-risk patients in the perioperative setting (2C) or in patients with septic shock.

In April 2019, KDIGO held a follow-up conference entitled Acute Kidney Injury with the following goals: determine best practices and areas of uncertainty in treating AKI; review key relevant literature published since the 2012 KDIGO AKI guideline; address ongoing controversial issues; identify new topics or issues to be revisited for the next iteration of the KDIGO AKI guideline; and outline research needed to improve AKI management. Their discussion identified emerging evidence related to the choice of crystalloid fluids and prevention of drug-related nephrotoxicity, which will be systematically reviewed in a forthcoming KDIGO update.

A lower proportion indicates better quality

Reference Type: CITATION

Reference Text: 'Ahmed, A., Vairavan, S., Akhoundi, A., Wilson, G., Chiofolo, C., Chbat, N., Kashani, K. (2015). Development and validation of electronic surveillance tool for acute kidney injury: A retrospective analysis. J Crit Care, 30(5), 988-993. doi: 10.1016/j.jcrc.2015.05.007'

Reference Type: CITATION

Reference Text: 'Chertow, G., Burdick, E., Honour, M., Boventre, JV., Bates, DW. (2005). Acute Kidney Injury, Mortality, Length of Stay, and Costs in Hospitalized Patients. 16(1):2265-3370. Journal of the American Society of Nephrology'

Reference Type: CITATION

Reference Text: 'Cho, A., Lee, J. E., Yoon, J. Y., Jang, H. R., Huh, W., Kim, Y. G., Oh, H. Y. (2012). Effect of an electronic alert on risk of contrast-induced acute kidney injury in hospitalized patients undergoing computed tomography. American Journal of Kidney Diseases, 60(1), 74-81'

Reference Type: CITATION

Reference Text: 'Goldstein, S. L., Mottes, T., Simpson, K., Barclay, C., Muething, S., Haslam, D. B., & Kirkendall, E. S. (2016). A sustained quality improvement program reduces nephrotoxic medication-associated acute kidney injury. Kidney Int, 90(1), 212-221. doi: 10.1016/j.kint.2016.03.031'

Reference Type: CITATION

Reference Text: 'Hoste, E. A., & Schurgers, M. (2008). Epidemiology of acute kidney injury: how big is the problem? Crit Care Med, 36(4 Suppl), S146-151. doi: 10.1097/CCM.0b013e318168c590'

Reference Type: CITATION

Reference Text: 'Kidney Disease: Improving Global Outcomes (KDIGO). (2012). KDIGO 2012 Clinical Pratice Guideline for the Evaluation and Management of Chronic Kidney Disease (Vol. 2).'

Reference Type: CITATION

Reference Text: 'Kirkendall, E. S., Spires, W. L., Mottes, T. A., Schaffzin, J. K., Barclay, C., & Goldstein, S. L. (2014). Development and performance of electronic acute kidney injury triggers to identify pediatric patients at risk for nephrotoxic medication-associated harm. Applied Clinical Informatics, 5(2), 313-333.'

Reference Type: CITATION

Reference Text: 'Lopes, J. A., & Jorge, S. (2013). The RIFLE and AKIN classifications for acute kidney injury: a critical and comprehensive review. Clinical Kidney Journal, 6(1), 8-14.'

Reference Type: CITATION

Reference Text: 'McCoy, A. B., Waitman, L. R., Gadd, C. S., Danciu, I., Smith, J. P., Lewis, J. B., Peterson, J. F. (2010). A computerized provider order entry intervention for medication safety during acute kidney injury: a quality improvement report. American Journal of Kidney Diseases, 56(5), 832-841.'

Reference Type: CITATION

Reference Text: 'Porter, C. J., Juurlink, I., Bisset, L. H., Bavakunji, R., Mehta, R. L., & Devonald, M. A. (2014). A real-time electronic alert to improve detection of acute kidney injury in a large teaching hospital. Nephrol Dial Transplant, 29(10), 1888-1893. doi: 10.1093/ndt/gfu082'

Reference Type: CITATION

Reference Text: 'Selby, N. M., Crowley, L., Fluck, R. J., McIntyre, C. W., Monaghan, J., Lawson, N., & Kolhe, N. V. (2012). Use of electronic results reporting to diagnose and monitor AKI in hospitalized patients. Clinical Journal of The American Society of Nephrology: CJASN, 7(4), 533-540.'

Reference Type: CITATION

Reference Text: 'Wilson, F. P., Yang, W., & Feldman, H. I. (2013). Predictors of Death and Dialysis in Severe AKI: The UPHS-AKI Cohort. Clinical Journal of the American Society of Nephrology, 8(4), 527-537. doi: 10.2215/cjn.06450612'

Reference Type: CITATION

Reference Text: 'Wilson, F. P., Reese, P. P., Shashaty, M. G., Ellenberg, S. S., Gitelman, Y., Bansal, A. D., Fuchs, B. (2014). A trial of in-hospital, electronic alerts for acute kidney injury: design and rationale. Clinical Trials, 11(5), 521-529.'

Reference Type: CITATION

Reference Text: 'Wilson, F. P., Shashaty, M., Testani, J., Aqeel, I., Borovskiy, Y., Ellenberg, S. S., Fuchs, B. (2015). Automated, electronic alerts for acute kidney injury: a single-blind, parallel-group, randomised controlled trial. Lancet, 385(9981), 1966-1974.'

Inpatient hospitalizations: Includes time in the emergency department and observation when the transition between these encounters (if they exist) and the inpatient encounter are within an hour or less of each other.

The numerator harm, AKI (stage 2 or greater), is defined as a substantial increase in serum creatinine value during the encounter, as evidenced by a subsequent increase in value at least 2 times higher than the lowest serum creatinine value, and the increased value is greater than the highest sex-specific normal value for serum creatinine. The following steps are performed to determine if this criterion for AKI is met: 

1.	To identify AKI, evaluate if any serum creatinine value obtained between 48 hours after the start of the encounter and either 30 days after the start of the encounter or discharge, whichever is sooner, is at least 1.5 times higher than the lowest value obtained within the prior 7 days . If yes, then:
2.	Evaluate if the increased serum creatinine is greater than the highest sex-specific normal value for serum creatinine. If yes, then:
3.	To stage AKI, evaluate if any serum creatinine value obtained between 48 hours after the start of the encounter and either 30 days after the start of the encounter or discharge, whichever is sooner, is at least 2 times higher than the lowest prior value (at any prior time) during that encounter . If yes, then:
4.	Evaluate if the increased serum creatinine value is greater than the highest sex-specific normal value for serum creatinine. If yes, then a harm (AKI stage 2 or greater) has been identified.

The highest normal serum creatinine value for females is defined as 1.02 mg/dL. 
The highest normal serum creatinine value for males is defined as 1.18 mg/dL.

The eGFR values are calculated using the CKD-EPI Creatinine Equation (2021), recommended by the National Kidney Foundation. This is a gender-specific, race-neutral formula.

The CKD-EPI Creatinine Equation used for females: 142×〖min((Serum Creatinine)/0.7,1)〗^(-0.241)×max〖((Serum Creatinine)/0.7,1)^(-1.200) 〗×〖0.9938〗^Age×1.012  

The CKD-EPI Creatinine Equation used for males: 142×〖min((Serum Creatinine)/0.9,1)〗^(-0.302)×max〖((Serum Creatinine)/0.9,1)^(-1.200) 〗×〖0.9938〗^Age  

The "index" serum creatinine is defined as the lowest serum creatinine value within the first 24 hours of encounter start. If there are no serum creatinine values within the first 24 hours, then the index is the first serum creatinine value within the first 48 hours of the encounter start. This serum creatinine value is used to identify and exclude patients with AKI at the start of the encounter.

The “index” eGFR is calculated using the “index” serum creatinine, patient sex, and patient age based on the CKD-EPI Creatinine Equation.

"Initiation" of kidney dialysis (CRRT, hemodialysis and peritoneal) during hospitalization is defined as documentation that kidney dialysis (CRRT, hemodialysis or peritoneal) was started during the encounter.

Present on admission (POA) is defined as the conditions present at the time the order for inpatient admission occurs. The POA Indicator is intended to differentiate conditions present at the time of admission from those conditions that develop during the inpatient admission. 
 - A POA Indicator of Y = yes (Diagnosis was present at time of inpatient admission).
 - A POA Indicator of N = no (Diagnosis was not present at time of inpatient admission.)
 - A POA Indicator of W = clinically undetermined
 - A POA Indicator of U = documentation insufficient to determine if the condition was present at the time 
   of inpatient admission

Per CMS and the Agency for Healthcare Research and Quality (AHRQ) convention, POA indicators of Y and W are accepted indicators of a diagnosis present on admission. POA indicators of N and U are accepted indicators of a diagnosis that is not present on admission.

To calculate the hospital-level measure result, divide the total numerator events by the total number of qualifying encounters (denominator). 

Qualifying encounters (denominator) include all inpatient hospitalizations for patients 18 years of age or older at the start of the encounter without a diagnosis of obstetrics, with a length of stay of 48 hours or longer who had at least one serum creatinine value after 48 hours from the start of the encounter.

Exclude encounters that do not have at least two serum creatine values within 48 hours of arrival. Two values are needed within this timeframe to determine if the patient has AKI or moderate-to-severe renal dysfunction on arrival.

Encounters for patients with an increase in serum creatinine value of at least 0.3 mg/dL between the index serum creatinine and any subsequent serum creatinine taken within 48 hours of the encounter start are excluded. Due to the variability of decimal precision within programming languages and calculation tools, the value of >=0.3 is expressed in the logic as >0.299.

Note the measure is currently confined to using mg/dL as the unit of measurement for creatinine and mL/min as the unit of measurement for eGFR results.

Only one harm (the first qualifying occurrence of acute kidney injury) is counted per encounter. 

This eCQM is an episode-based measure. An episode is defined as each inpatient hospitalization or encounter that ends during the measurement period.

This version of the eCQM uses QDM version 5.6.  Please refer to the eCQI resource center (https://ecqi.healthit.gov/qdm) for more information on the QDM.

TBD

Inpatient hospitalizations for patients 18 years of age or older at the start of the encounter without a diagnosis of obstetrics, with a length of stay of 48 hours or longer who had at least one serum creatinine value after 48 hours from the start of the encounter

Equals Initial Population

Inpatient hospitalizations for patients with an increase in serum creatinine value of at least 0.3 mg/dL between the index serum creatinine and a subsequent serum creatinine taken within 48 hours of the encounter start

Inpatient hospitalizations for patients with the index eGFR value of <60 mL/min within 48 hours of the encounter start. 

Inpatient hospitalizations for patients who have less than two serum creatinine results within 48 hours of the encounter start.

Inpatient  hospitalizations for patients who have kidney dialysis (CRRT, hemodialysis or peritoneal dialysis) initiated within 48 hours of the encounter start. 

Inpatient hospitalizations for patients with at least one specified diagnosis present on admission that puts them at extremely high risk for AKI: 
•  Hemolytic Uremic Syndrome (HUS)
•  Large Body Surface Area (BSA) Burns
•  Traumatic Avulsion of Kidney
•  Rapidly Progressive Nephritic Syndrome
•  Thrombotic Thrombocytopenic Purpura    
 
Inpatient hospitalizations for patients who have at least one specified procedure during the encounter that puts them at extremely high risk for AKI: 
•  Extracorporeal membrane oxygenation (ECMO)                                     
•  Intra-Aortic Balloon Pump
•  Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) 
•  Nephrectomy

Inpatient hospitalizations for patients who develop AKI (stage 2 or greater) during the encounter, as evidenced by: 

A subsequent increase in serum creatinine value at least 2 times higher than the lowest serum creatinine value, and the increased value is greater than the highest sex-specific normal value for serum creatinine.

Or:

Kidney dialysis (CRRT, hemodialysis or peritoneal dialysis) initiated 48 hours or more after the start of the encounter.

Not applicable

None

For every patient evaluated by this measure also identify payer, race, ethnicity and sex