Presentation on theme: "Iman Hassan, MD Pulmonary Medicine Department ICU Scoring Systems."— Presentation transcript:
Iman Hassan, MD Pulmonary Medicine Department E-mail: firstname.lastname@example.org ICU Scoring Systems
Introduction ►Severity of illness scoring systems are developed to evaluate delivery of care & provide prediction of outcome of groups of critically ill patients who are admitted to ICUs. ►Scoring systems consists of two parts: a severity score, which is a number (generally the higher this is, the more severe the condition) & a calculated probability of mortality.
Classification of Scoring Systems ►Anatomical scores: depend on the anatomical area involved. Mainly used for trauma patients [e.g. abbreviated injury score (AIS) & injury severity score (ISS)]. ►Therapeutic weighted scores: based on the assumption that very ill patients require more complex interventions & procedures than patients who are less ill e.g., the therapeutic intervention scoring system (TISS). ►Organ-specific score: similar to therapeutic scoring; the sicker a patient the more organ systems will be involved, ranging from organ dysfunction to failure [e.g. sequential organ failure assessment (SOFA)].
Classification of Scoring Systems ►Physiological assessment: based on the degree of derangement of routinely measured physiological variables [e.g. acute physiology and chronic health evaluation (APACHE) & simplified acute physiology score (SAPS)]. ►Simple scales: based on clinical judgment (e.g. survive or die). ►Disease specific: [e.g. Ranson’s criteria for acute pancreatitis, subarachnoid haemorrhage assessment using the World Federation of Neurosurgeons score & liver failure assessment using Child-Pugh or model for endstage liver disease (MELD) scoring].
Types of Scoring Systems First day scoring systems: ►APACHE scoring systems ►SAPS (simplified acute physiology score) ►MPM (mortality prediction model) Repetitive scoring systems: ►OSF (organ system failure) ►SOFA (sequential organ failure assessment) ►ODIN (organ dysfunction & infection system) ►MODS (multiple organs dysfunction score) ►LOD (logistic organ dysfunction)
The Ideal Scoring System 1.On the basis of easily/routinely recordable variables 2.Well calibrated 3.A high level of discrimination 4.Applicable to all patient populations 5.Can be used in different countries 6.The ability to predict functional status or quality of life after ICU discharge. No scoring system currently incorporates all these features
Severity scores in Medical & Surgical ICU 1980-85 APACHEAPACHE SAPSSAPS APACHE IIAPACHE II 1986-1990 SAPS IISAPS II MPMMPM 1990-95 APACHE IIIAPACHE III MODSMODS MPM IIMPM II ODINODIN 1996-2000 SOFASOFA CISCIS 2000- current SAPS IIISAPS III APACHE IVAPACHE IV
Common Scoring Systems Acute Physiology & Chronic Health Evaluation (APACHE)
►The APACHE score is the best-known & most widely used score with good calibration & discrimination. ►The original APACHE score was developed in 1981 to classify groups of patients according to severity of illness & was divided into 2 sections: physiology score to assess the degree of acute illness & preadmission evaluation to determine the chronic health status of the patient.
Original APACHE score: ►34 physiologic measures (0-4) Sum of all acute physiology scores (APS) Worst of the initial 24 hour after ICU admission ►Chronic health A (excellent health) B C D (severe chronic organ system insufficiency) Crit Care Med 1981; 9:591
Original APACHE score: Crit Care Med 1981; 9:591
APACHE II score: ►The APACHE II scoring system was released in 1985 and included a reduction in the number of variables to 12. ►The APACHE II scoring system is measured during the first 24 h of ICU admission with a maximum score of 71. A score of 25 represents a predicted mortality of 50% and a score of over 35 represents a predicted mortality of 80%. ►APACHE II score is sum of: Acute physiology score Age Chronic health score
APACHE II score: ►The APACHE II score (0 – 71) ►Total APACHE II = A+B+C A → APS points B → Age points C → Chronic Health points
The Glasgow Coma Scale (GCS) Lancet 1974;304:81-84
APACHE III score: ►APACHE III, released in 1991, was developed with the objectives of improved statistical power, ability to predict individual patient outcome, and identify the factors in ICU that influence outcome variations but it is far more complex than the 2 previous scoring systems. ►17 physiological variables & Total score (0 – 299) ► Acid-base disturbances ► GCS score – based on the worst ►Age score ►7 co-morbidities (cardiac, respiratory & renal failures excluded) Chest 1991, 100:1619 - 1636
The APACHE III Scoring for Chronic Health Condition Chronic health condition (Co-morbid condition) 1)AIDS → 23 2)Hepatic failure → 16 3)Lymphoma → 13 4)Metastatic cancer → 11 5)Leukemia/multiple myeloma → 10 6)Immunosuppression → 10 7)Cirrhosis → 4
APACHE score ROC Prediction at 50%probability Calibration APACHE II0.8585.5 APACHE III version (H)0.9088.248.7 APACHE III version (I)Unpublished 24.2 APACHE III (H) in 2003-04 cohortUnpublished 24.2
APACHE IV score: ►The APACHE IV scoring system was published in 2006. Limitations: ►Complexity – has 142 variables. ►But web-based calculations can be done. ►Developed and validated in ICUs of USA only. Crit Care Med 2006; 34:1297–1310
Common Scoring Systems Simplified Acute Physiology Score (SAPS)
►The SAPS score was first released in 1984 as an alternative to APACHE scoring. ►The original SAPS score is obtained in the first 24 h of ICU admission by assessment of 14 physiological variables, but no input of pre-existing disease was included. ►It has been superseded by the SAPS II & SAPS III, both of which assess the 12 physiological variables in the first 24 h of ICU admission & include weightings for pre-admission health status & age.
Simplified Acute Physiology Score (SAPS) ►Predicted mortality = -14.4761 + 0,0844 * SAPS II + 6.6158 * log (SAPS II+1) ►Area under ROC for SAPS is 0.8 where as SAPS II has a better value of 0.86 JAMA 1993;270:2957-2963
SAPS III ►Scores based on data collected within 1 st hour of entry to ICU. ►Allows predicting outcome before ICU intervention occurs. ►Better evaluation of individual patient rather than an ICU. ►Limitations: Time for collecting data Can have greater missing information Intensive Care Med 2005; 31:1345–1355
Common Scoring Systems Sequential Organ Failure Assessment (SOFA)
►Previously known as Sepsis-related Organ Failure Assessment because it was initially developed in 1994 to describe the degree of organ dysfunction associated with sepsis in a mixed, medical-surgical ICU patients. ►Nowadays, it has since been validated to describe the degree of organ dysfunction in various ICU patient groups with organ dysfunctions not due to sepsis. ►The SOFA score involves six organ systems (respiratory, cardiovascular, renal, hepatic, central nervous, coagulation), and the function of each is scored from 0 (normal function) to 4 (most abnormal), giving a possible score of 0 to 24.
Sequential Organ Failure Assessment (SOFA) ►Mortality rate increases as number of organs with dysfunction increases. ►Unlike other scores, the worst value on each day is recorded. ►A key difference is in the cardiovascular component; instead of the composite variable, the SOFA score uses a treatment-related variable (dose of vasopressor agents).
Sequential Organ Failure Assessment (SOFA) ►Maximal (highest total) SOFA score: is the sum of highest scores per individual during the entire ICU stay. A score of >15 predicted mortality of 90%. ►Mean SOFA score (ΔSOFA): is the average of all total SOFA scores in the entire ICU stay. ΔSOFA for 1 st 10 days is significantly higher in non-survivors. ►Delta SOFA score: maximum SOFA – admission SOFA Crit Care Med 1998;26:1793-1800
Common Scoring Systems Multiple Organ Dysfunction Score (MODS)
►The MODS scores six organ systems: respiratory (PO 2 /FIO 2 in arterial blood); renal (serum creatinine); hepatic (serum bilirubin); cardiovascular (pressure-adjusted heart rate); haematological (platelet count) & CNS (Glasgow Coma Score) with weighted scores (0–4) awarded for increasing abnormality of each organ systems. ►Scoring is performed on a daily basis. ►Total score ranges from 0-24. ►Area under ROC 0.936. ►ΔMODS predicts mortality to a greater extent than Admission MODS score. Crit Care Med. 1995; 23:1638-52
Common Scoring Systems Clinical Pulmonary Infection Score (CPIS)
►A score developed to establish a numerical value of clinical, radiographic, and laboratory markers of pneumonia. ►Serial measurements of the CPIS could be used to identify survivors versus non-survivors as early as day 3 of therapy. ►The CPIS correlated with mortality rate. ►CPIS scores > 6 suggest pneumonia. ►CPIS is an important variable to monitor during VAP therapy. Patients with VAP having CPIS ≤ 6 can safely discontinue antibiotics after 3 days. AJRCCM 2000;162:501-511
Clinical Pulmonary Infection Score (CPIS) AJRCCM 2000;162:501-511 Score012 Temperature ≥36.5 & ≤38.4≥38.5 & ≤38.9≥39 & ≤36.4 TLC ≥4 & ≤11 12 Tracheal Secretions NoneNon-purulentPurulent Oxygenation PaO 2 /FIO 2 mmHg >240 or ARDS≤240 & no ARDS Chest RadiographNo opacity Diffuse (patchy) opacities Localized opacity Progression of Radiograpgic Opacities No progression Progression (after HF & ARDS excluded) Culture of Tracheal Aspirate Pathogenic bacteria cultured in rare/few quantities or no growth Pathogenic bacteria cultured in moderate or heavy quantity
Common Scoring Systems Mortality Probability Model (MPM)
►Not applicable for patients <14yrs, patients with burns, cardiac/ cardiac surgery patients. ►MPM score: Admission MPM (MPM0) →11 variables MPM at 24 Hrs (MPM24) → 14 variables MPM at 48 Hrs (MPM48) → 11 variables MPM over the time (MPMOT) → (MPM24-MPM0) (MPM48-MPM24) ►Probability is derived directly from these variables. ►MPMOT predicted better than MPM0 for long term patients. Crit care med 1988;16:470-477
MPM 0 Variable10 Level of consciousness Coma / deep stuporNo coma/deep stupor Admission EmergencyElective Prior CPR YesNo Cancer PresentAbsent CRF PresentAbsent Infection ProbableNot probable Previous ICU admission in 6 mo YesNo Surgery before ICU admission YesNo SBP HR 10 beat/min relative risk Age 10 years relative risk
Common Scoring Systems Therapeutic Intervention Scoring System (TISS)
►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 patient on 76 possible clinical interventions
TISS 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 Scores Scores for Pediatric patients: PRISM (Pediatric RISk of Mortality) P-MODS (Pediatric MODS) DORA (Dynamic Objective Risk Assessment) PELOD (Pediatric Logistic Organ Dysfunction) PIM II (Paediatric Index of Mortality II) PIM (Paediatric Index of Mortality) Scores for surgical patients: Thoracoscore (thoracic surgery) Lung Resection Score (thoracic surgery) EUROSCORE (cardiac surgery) ONTARIO (cardiac surgery) Parsonnet score (cardiac surgery) System 97 score (cardiac surgery) QMMI score (coronary surgery) Early mortality risk in redocoronary artery surgery MPM for cancer patients Scores for trauma patients: Trauma Score Revised Trauma Score Trauma and injury Severity score (TRISS) A Severity Characterization of trauma (ASCOT)
Which score to use? ►APACHE, SAPS, MPM → only of historic significance ►APACHE II → most widely used in USA ►SAPS II → commonly used in Europe ►APACHE III → not in public domain ►SAPS III, APACHE IV → better design ►MODS & LODS → uncommonly used