Transcript ICNARC Model

• Louie Plenderleith
New Case mix adjustment
Systems
Scottish SMRs by APACHE system: 2001.
unit SMR
2
unit 95% CI
unit 95% CI
1.8
1.6
1.4
SMR
1.2
1
0.8
0.6
0.4
0.2
0
GI
Resp
CVS
Neuro
Trauma
General
APACHE system
Scottish Intensive Care Society Audit Group,
Annual Report 2003.
www.scottishintensivecare.org.uk
Renal
Metabolic
Haem
Calibration
Apache II Exclusions
551 patients (6%) excluded
Age < 16 yrs
Stay < 8 hours
Diagnosis
Bundles
• Knaus WA, Draper EA, Wagner DP, et al:
• APACHE II: A severity of disease classification
• system.
• Crit Care Med 1985
Ideal Scoring System
• More Accurate
• Inclusive
• Same (or less) data
• Free
New Scoring methods
• SAPS 3 (2005)
– 19,507 patients, 305 ICUs, 4 Continents
• APACHE IV (2006)
• 131,618 patients, 104 ICUs, USA
• ICNARC Method (2007)
– 231,930 patients, 163 ICUs, England, Wales & NI
ICNARC Calibration
SAPS 3 Calibration
APACHE IV Calibration
Exclusions
• APACHE IV
–
–
–
–
–
Readmissions
< 16 years
< 4 hours
Admitted from another ICU
Hospital Stay > 1 year
• SAPS 3
– Readmissions
– < 16 years
• ICNARC
– Readmissions
Data collected currently
ICNARC model
APACHE IV
SAPS III
Heart rate
Highest
Most abnormal
Highest
Temp
Highest
Most abnormal
Highest
Respiratory Rate
Lowest
Most abnormal
Intubated
Y /N
PaO2/FlO2
Both required
Both Required
Acid Base
Lowest pH
pCO2 / pH grid
Urea
Highest
Most abnormal
Creatinine
Highest
Most abnormal (Modified in ARF)
Sodium
Highest
Most abnormal
Bilirubin
Urine Output (24 hours)
Most abnormal
Yes
Haematocrit
Both required
Highest
Highest
Yes
Most abnormal
WBC
Lowest
Most abnormal
Paralyzed/sedated?
Yes (scored)
Use GCS from up to 12 hours previously
GCS
Lowest (unless sedated)
Grid
lowest
Current list
own list, but all present
Chronic Health
Highest
Age
Yes
Yes
yes
Source of Admission
Yes
Yes
Yes
CPR
additional coefficient
Yes
Yes
Length of Stay pre ICU
Type of surgery
Planned or unplanned admission
In Source of Admission
yes
Data not collected
BP
ICNARC model
APACHE IV
SAPS III
Lowest systolic BP
most abnormal MAP
Lowest Systolic
Albumin
Most abnormal
Glucose
Most abnormal
Platelets
Diagnosis / reason for
admission
Lowest
New list
New list
Limited list
Site of surgery
Limited list
Preadmission Rx
Inotropes
Acute infection at ICU Admission
Yes / No
Cost
• SAPS 3
Public domain
• APACHE 4
Public domain
• ICNARC
Not public Domain
Should we Change
• Loss of historical comparisons
• Probably no change in data collection burden
• Have to relearn definitions
• Will it work better for SICSAG?
What do we do?