medexter®
Vom Forschungsergebnis in die klinische Routine –Klinische Entscheidungsunterstützung mit Moni-ICU
Klaus-Peter Adlassnig
Section for Medical Expert and Knowledge-Based SystemsCenter for Medical Statistics, Informatics, and Intelligent SystemsMedical University of ViennaSpitalgasse 23A-1090 Vienna, Austria
and
Medexter Healthcare GmbHBorschkegasse 7/5A-1090 Vienna, Austria
Workshop GMDS-Arbeitsgruppe „Wissensbasierte Systeme in der Medizin“, Berlin,04 April 2011
medexter®
ESBL - extended spectrum beta-lactamase
VRE - vancomycin-resistant enterococcus
MDR-TB - multidrug-resistant tuberculosis
increaseddisposition by low immunity
MRSA - methicillin-resistant Staphylococcus aureus
exposure to pathogens
entry sites
medexter®
Moni-ICU
knowledge-based identification and automated monitoring of hospital-acquired infections in adult patients in intensive care units
patient-specific alerts
infection control
natural-language definitions of nosocomial
infections
Fuzzy theories
Artificial intelligence
Monitoringof
nosocomial infections
knowledge-based systems
fuzzy sets and logic
ICUICU
microbiology
cockpit surveillance remote
clinical data
Medicine
data on microorganisms
cockpit surveillance at ward ICU
medexter®
Processing layers
linguistic NI definitions
basic concepts:symptoms, signs, test results, clinical findings
intermediate concepts:pathophysiological states
abstraction:rules, type-1 & type-2 fuzzy sets, temporal abstraction
feature extraction:mean values, scores, …
preprocessing: missing data, plausibility, …
ICU + NICU patient data bases
y inference stepsreasoning
symbols
data-to-symbolconversion
data
x inference steps
layer n-x-y-1
layer 2
layer 1
layer n-x-y
layer n-y
layer n (goal)
layer 0 (start)
… ……
CDC, HELICS, KISS
Bloodstream infection with clinical signs and growth of same skin contaminant from two separate blood samples
BSI-A2
1
clinical_signs_of_BSI (t-1d, t, t+1d)
same_skin_contaminant_from_two_separate_blood_samples
Decomposition—clinical signs
clinical_signs_of_BSI (t-1d, t, t+1d)[yesterday, today, tomorrow]
=fever (t-1d)
hypotension (t-1d)
clinical_signs_of_BSI (t-1d) = leucopenia (t-1d)
leucocytosis (t-1d)
CRP increased (t-1d)
fever (t)
hypotension (t)
clinical_signs_of_BSI (t) = leucopenia (t)
leucocytosis (t)
CRP increased (t)
fever (t+1d)
hypotension (t+1d)
clinical_signs_of_BSI (t+1d) = leucopenia (t+1d)
leucocytosis (t+1d)
CRP increased (t+1d)
fever (t-1d) ...
body temperature
fever (t)
thermoregulation applied
fever (t+1d) ...
Clinical signs—fever
data import
intensive care unit
maximum value of the day
e.g., 38.5 CC
1
037 37.5 38 38.5
Decomposition—skin contaminant
first blood culture
- coagulase-negative staphylococci
- Micrococcus sp.
- Propionibacterium acnes
- Bacillus sp.
- Corynebacterium sp.
same_skin_contaminant_from_two_separate_blood_samples
second blood culture
- coagulase-negative staphylococci
- Micrococcus sp.
- Propionibacterium acnes
- Bacillus sp.
- Corynebacterium sp.
data import
microbiology (within 48 hours)
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Results by Moni-ICU
• 35 HELICS + 19 KISS definitions of ICU-acquired infections– 6 + 3 definitions of bloodstream infections– 17 + 9 definitions of ICU-acquired pneumonias– 9 + 7 definitions of urinary tract infections– 3 + 0 definitions of central venous catheter-related infections
• Moni-ICU is operated at 12 ICUs at the Vienna GeneralHospital (96 beds)
• Moni-ICU is connected to HIS, LIS, and PDMS
• cockpit surveillance for infection control unit– automated daily and/or manual activation
• evaluation over a period of 2 months (2 ICUs)– 24 out of 28 patients TP (detected and correct), 0 FPs, 4 FNs (cause:
missing data, variable missing in rule condition, …), many TNs– manual evaluation of criteria: each episode of infection > 2 hours– with Moni: < 5 min per episode
medexter®
Sources of success
• clinical* no diagnoses* two-step reporting
• methodological* pure knowledge-based system* consensual classification criteria* hierarchical layers of data and knowledge* fuzzy set theory and logic
• technical* separation of PDMS data collection, service-oriented rule engine server,
knowledge packages, and web-based infection control application* integration of different hospital IT systems (HIS, LIS, PDMS, CDSS server)
• administrative* no additional data entry* almost uniform PDMS data sources at 12 ICUs* support by medical administration* several lead users