icu scoring systems
Post on 25-Nov-2014
458 Views
Preview:
TRANSCRIPT
ICU Scoring Systems
22nd June 2007
Ulster Hospital
Gail Browne
ICU Scoring Systems
• Why are scoring systems needed?
• Classifying scoring systems
• History of scoring systems
• Examples of scoring systems
• Recent developments
• Selecting a scoring system
• Discussion
“It’s more important to know what sort of person this
disease has, than what sort of disease this person has.”
William Osler 1849-1919
Why are scoring systems needed?
• Scoring systems can provide:
- Case-mix adjustment for evaluative research- A tool for comparative audit - SMR- A mechanism to decide resource allocation- An aid for the clinical management of patients
Scoring Systems
• Specific or generic• Anatomical or physiological• Anatomical systems – assess extent of injury
(eg injury severity score)• Physiological systems – assess impact of
injury on function (eg GCS)
First Scoring Systems
• Developed for trauma pts• Specific anatomical methods:
- abbreviated injury score 1969- Burns score 1971- Injury severity score 1974
• Specific physiological methods:- trauma index 1971- Glasgow coma scale 1974- Trauma score 1981- Sepsis score 1983
Scoring Systems
• Later scoring systems generic• Measuring severity by treatment – TISS
(Therapeutic Intervention Scoring System) 1974
• Measuring severity of organ dysfunction based on type & amount of tx received
• Measuring severity by patient characteristics & physiological measurements - SAPS, APACHE, MPM
Scoring System Development
• Pt variables that influence survival collected by consensus or statistical analysis
• Scoring model developed from large cohort & validated on another cohort
Classifying Scoring SystemsGeneral Scores Specialised &
Surgical Intensive Care – Preop evaluation
Trauma Scores
Therapeutic Intervention Nursing Scores
• SAPS II expanded & predicted mortality• APACHE II & predicted mortality• SOFA (Sequential Organ Failure Assessment)• MODS (Multiple Organ Dysfunction Score)• ODIN (Organ Dysfunctions &/or Infection)• MPM (Mortality Probability Model)• LODS (Logistic Organ Dysfunction System)• TRIOS (Three days recalibrated ICU outcome Score)
• Lung resection score
• EUROSCORE
• ONTARIO
• Parsonnet score
• System 97 score
• QMMI score
• POSSUM (physiologic & operative severity score for the enUmeration of mortality & morbidity)
• IRISS score
• GCS
• ISS (Injury Severity Score)
• RTS (revised trauma score)
• TRISS (trauma injury severity score)
• ASCOT (a severity characterization of trauma)
• 24h – ICU Trauma Score
• TISS (therapeutic intervention scoring system)
• TISS – 28 (simplified TISS)
History
• 1953 – Virginia Apgar• 1974 – Glasgow Coma Scale
• Quantifying relationship between disease severity and outcome
• 1980s – acute physiology and chronic health evaluation (APACHE) & simplified acute physiological score (SAPS)
History• APACHE & SAPS – physiologically based
classification systems• General severity scores• Aim at stratifying patients based on their severity• 1985 – 1993: general outcome prediction models• 1991 – APACHE III• 1993 – SAPS II• 2005 – SAPS III (www.saps3.org)• 2006 – APACHE IV• During process of evolution of models, main
prognostic determinants of outcome changed
APACHE
• William Knaus• Initially 34 physiological variables• 1985 – APACHE II 12 variables• APACHE II allows probability of death before
hospital discharge to be estimated• Standardised mortality ratio
APACHE II score = (acute physiology score) + (age points) + (chronic health points)
Scores range from 0 – 71 Score risk of hospital death
SAPS (Simplified Acute Physiology Score)
• Le Gall reduced former 34-variable APACHE score to 14 parameters
SOFA (Sequential Organ Failure Assessment) Score
MPM (Mortality Prediction Models)
• Developed by Stanley Lemeshow• Uses data collected during first hour of ICU
admission; 24 hours; 72 hours• Series of true/false questions• Weighted according to their individual
contribution to mortality
TISS (Therapeutic Intervention Scoring System)
• Measuring sickness severity based on type & amount of treatment received
• Both clinical & administrative applications:- assessing severity of illness- Determining resource requirements- Assessing use of critical care facilities & function– Not standardised
• Daily data collected from each pt on 76 possible clinical interventions
TISS (Therapeutic Intervention Scoring System)
• Four classes of pt recognised:- Class I < 10 points does not require ICU- Class II 10-19 points 1:2 nurse:pt ratio- Class III 20-39 points 1 ICU nurse- Class IV > 40 points 1:1 nurse:pt ratio++
Other Scoring Systems…
CPIS (Clinical Pulmonary Infection) Score
Early Warning Physiological Scoring Systems
• MERIT study• SOCCER study• The Worthing physiological scoring system –
BJA June 2007
The Worthing PSS
0 1 2 3
Ventilatory Frequency
19 20-21 22
Pulse 101 102
SBP 100 99
Temp 35.3 < 35.3
Oxygen Sat in air
96 - 100 94 - <96 92 - < 94 < 92
AVPU Alert Other
(Duckitt et al, 2007)2,3,4 – be alert!
5 urgent doctor review
Recent developments - New Models
• SAPS III admission model – chronic health & circumstances of ICU admission now responsible for approx. ¾ prognostic power of model.
• APACHE IV Model – Jack Zimmerman• MPM III Model• ICNARC Model
Selecting a Scoring System
• Depends on proposed use• Validity• Reliability• Calibration • Discrimination• Outcome from ICU…?• Other scoring systems eg sedation scores,
sepsis bundles,CPIS, early warning physiological scoring systems, POSSUM…..
Discussion…
top related