Technical Note

Ambulatory Care Sensitive Conditions (ACSC)


Inclusion criteria†:

Any most responsible diagnosis code of:

  • Grand mal status and other epileptic convulsions
    ICD-9/9CM: 345
    ICD-10-CA: G40, G41
  • Chronic obstructive pulmonary diseases (COPD)
    • Any most responsible diagnosis (MRDx) code of
      ICD-9/9CM: 491, 492, 494, 496
      ICD-10-CA: J41, J42, J43, J44, J47
    • MRDx of Acute lower respiratory infection, only when a secondary diagnosis1 of J44 in ICD-10-CA or 496 in ICD-9/9CM is also present
      ICD-9/9CM: 466, 480 – 486, 487.0
      ICD-10-CA: J10.0, J11.0, J12-J16, J18, J20, J21, J22
  • Asthma
    ICD-10-CA: J45
  • Diabetes
    250.0, 250.1, 250.2, 250.7
    ICD-9-CM: 250.0, 250.1, 250.2, 250.8
    ICD-10-CA: E10.0^^, E10.1^^, E10.63, E10.64, E10.9^^
    E11.0^^, E11.1^^, E11.63, E11.64, E11.9^^
    E13.0^^, E13.1^^, E13.63, E13.64, E13.9^^
    E14.0^^, E14.1^^, E14.63, E14.64, E14.9^^
  • Heart failure and pulmonary edema*
    428, 518.4
    ICD-10-CA: I50, J81
    *Excluding cases with cardiac procedures
  • Hypertension*
    ICD-9/9CM: 401.0, 401.9, 402.0, 402.1, 402.9
    ICD-10-CA: I10.0, I10.1, I11
    *Excluding cases with cardiac procedures
  • Angina*
    ICD-9: 411, 413
    ICD-9-CM: 411.1, 411.8, 413
    ICD-10-CA: I20, I23.82, I24.0, I24.8, I24.9
    *Excluding cases with cardiac procedures

List of cardiac procedure codes2 for exclusion:

CCP: 47^^, 480^-483^, 4891, 4899, 492^-495^, 497^, 498^
ICD-9-CM: 336, 35^^, 36^^, 373^, 375^, 377^, 378^, 3794-3798
CCI: 1HA58, 1HA80, 1HA87, 1HB53, 1HB54, 1HB55, 1HB87, 1HD53, 1HD54, 1HD55, 1HH59, 1HH71, 1HJ76, 1HJ82, 1HM57, 1HM78, 1HM80, 1HN71, 1HN80, 1HN87, 1HP76, 1HP78, 1HP80, 1HP82, 1HP83, 1HP87, 1HR71, 1HR80, 1HR84, 1HR87, 1HS80, 1HS90, 1HT80, 1HT89, 1HT90, 1HU80, 1HU90, 1HV80, 1HV90, 1HW78, 1HW79, 1HX71, 1HX78, 1HX79, 1HX80, 1HX83, 1HX86, 1HX87, 1HY85, 1HZ53 rubric (except 1HZ53LAKP), 1HZ55 rubric (except 1HZ55LAKP), 1HZ56, 1HZ57, 1HZ59, 1HZ80, 1HZ85, 1HZ87, 1IF83, 1IJ50, 1IJ55, 1IJ57, 1IJ76, 1IJ86, 1IJ80, 1IK57, 1IK80, 1IK87, 1IN84, 1LA84, 1LC84, 1LD84, 1YY54LANJ

Exclusion criteria:

  1. Death before discharge
  2. Individuals age 75 years and older
  3. Admission category recorded as newborn or stillbirth


A new “combination” code for acute lower respiratory infections in patients with Chronic Obstructive Pulmonary Disease (J44.0) was introduced with ICD-10-CA and has no equivalents in ICD-9/ICD-9-CM. According to the Canadian Coding Standards, if COPD patients presented with acute respiratory infections, only J44.0 should be used, but not the other codes from the J44 rubric. This code should be assigned as most responsible diagnosis (MRDx) with pneumonia assigned as a secondary diagnosis. To ensure that COPD patients presented with acute lower respiratory infections are captured and to correct evident erroneous application of the combination code, cases coded with a primary diagnosis of an acute lower respiratory infection and a secondary diagnosis of J44 are also included in the COPD case count.

A unique code for Diabetes with hypoglycaemia (ICD-10-CA: E10.63, E11.63, E13.63, E14.63) does not exist in the ICD-9/ ICD-9CM classification systems. This condition was coded using ICD-9 code of 250.7 and ICD-9CM code of 250.8, which also included diabetes with other specific manifestations. However, this should have minimal effect on the comparability of rates coded based on ICD-9 and ICD-10 coding systems.

1 The following diagnosis categories are presented to broadly classify ACSC cases into composite conditions and are not intended to be used for producing rates outside of the ACSC context.

“Secondary diagnosis” refers to a diagnosis other than most responsible

2 Code may be recorded in any position. Procedures coded as cancelled, previous and “abandoned after onset” are excluded.