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Patient-Centered InformationSystems

Medical Informatics 1WS 2006/2007

Patient-Centered Information Systems

• Primary Care

• Clinical Departmental Systems

• Clinical Support Systems

• Nursing Information Systems

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Primary Care

• First-line health care (General

Practitioners)

• Medical Software

Primary Care

• Primary care information systems:developments– Evidence-Based Medicine

http://www.cochrane.de

– E.g. http://www.healthgate.at

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Clinical Departmental Systems

Clinical Departmental Systems

Computers in clinical departments

• Administrative support

• Patient data collection

• Decisions• Monitoring

• Reporting

• Assessment

• Research

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Internal Medicine

• Oncology– Oncology registration systems

– E.g. http://www.cancer.gov

– http://cgap.nci.nih.gov

• Nephrology– Monitoring dialysis

• Endocrinology– Diabetes

• Hematology– Hemophilia

Internal Medicine

• Endoscopy

• Organ Transplants– Eurotransplant (Leiden, NL); 3000 transplants per year

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Cardiology

• Electrocardiography

• Coronary angiography

• Cardiac scintigraphy

• Echocardiography

Clinical Departmental Systems

• Neurology

• Pediatrics

• Obstetrics (and gynecology)

• Surgery

• Psychiatry

• Virtual reality, augmented reality

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Clinical Departmental Systems

• Critical Care

Clinical Departmental Systems

• Critical Care– Patient Data Management Systems

• Data acquisition

• Data reduction

• Error checking

• Information display

• Decision support

• Integration (also systems outside the ICU)

• Ethical and legal aspects (auditing)

• Research

• Efficiency

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Clinical Support Systems

Medical Informatics 1WS 2006/2007

Clinical Support Departments

• Radiology

• Physiological functional laboratory

• Pathology

• Clinical Chemistry

• Pharmacy

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Radiology Information Systems

The main goal of RIS is to support both themedical and administrative functions of radiology

Imaging Systems

• Subtraction Angiography

• Computed Tomography

• Magnetic Resonance Imaging

Radiology Information Systems

Overview of tasks in a radiology information system

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Radiology Information Systems

• PACs

• Light box: better brightness

• DICOM

Function Laboratories

Examine the function of organs or organ systems (as afunction of time)

• Heart (ECG, echocardiography, scintigraphy,angiography)

• Respiratory system (spirography)

• Nervous system (EEG, EMG)

• Visual control system (EOG)

• Auditory system (audiography)

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Function Laboratories

Schematic diagram of systems operational in different

function departments

Function Laboratories

Schematic diagram of modular ECG processing

Electrocardiography

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Function Laboratories

Prior knowledge for ECG signal processing

• ECG is a quasiperiodic signal, but it may also contain stochasticcomponents (atrial flutter, fibrillation, or ventricular fibrillation)

• It has one dominant waveform, but it may also contain multiformextrasystoles

• Frequency domain between 0.15 and 150 Hz

• Disturbances (loose electrodes, 50 or 60 Hz, pacemaker pulses,EMG)

• Amplitude range: -10 mV to +10 mV

• Different application areas (diagnostic, ambulatory monitoring,screening, intensive care, research)

Function Laboratories

Report of a computer processed ECG

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Function Laboratories

Spirography

• Lung function measurements (flows, volumes,pressures)

• Respiratory gases (pCO2, pO2)

Function LaboratoriesEEG

• Stochastic signal

• Frequency analysis (FT)

• Evoked potentials

Evoked potentials in seven EEG leads resulting from stimulation by light flashes.

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Pathology Laboraty

• Diagnosis in the pathology laboratory

• The diagnostic process

• Potential sources of diagnostic errors

• The role of computers in pathology

Pathology Laboratory

Diagnosis in the pathology laboratory

• Postmortem

• Diagnosis from observations of tissue orseparate cells taken from live patients– Paraffin slice (tissue: histology, cells: cytology)

– Frozen tissue

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Pathology LaboratoryTissue/stain Reference Disagreement (%)

Bladder tumors Ooms et al. 1983 50Bone tumors Sissons 1975 ConsiderableBone marrow Morley, Blake 1975 0-56Bowel disease Dundas et al. 1987 MinorBreast cancer Stenkvist et al. 1983 23-40Cervical cancer Ringsted et al. 1978 4-58Colorectal cancer Thomas et al. 1983 31-44Endometrium Baak et al. 1981 25Gastric cancer Pagnini, Rugge 1982 4-17Hydatidiform mole Javey et al. 1979 45-66Immunostaining Muir et al. 1987 10-15Liver Garceau 1964 48Lung tumors Hansen 1982 10-considerableLymphomas Argyle et al. 1989 20-50Melanomas Larsen et al. 1980 30Muscle fiber Pool et al. 1979 40Nervous system Daumas-Duport et al. 4-19Esophagus Reid et al. 1988 13-28Ovarian tumors Stalsberg et al. 1988 25-59Soft tissue sarcoma Coindre et al. 1986 19-39Thyroid cancer Ron et al. 1986 10-15Urothelial cells Sherman et al. 1984 ConsiderableVarious Penner 1973 4-87

Disagreement Figures in Pathology Diagnoses.

aafter Baak JPA. Manual of Quantitative Pathology in Cancer Diagnosis and Prognosis. Heidelberg: Springer Verlag, 1991:14 (partly cited).

Pathology Laboratory

The diagnostic process

• Focus on certain features (extensive training)– Selection of relevant features

– Comparison with reference knowledge

– Verbal expression

– Diagnostic classification

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Pathology Laboratory

Potential sources of diagnostic errors

• Context (e.g. parathyroid tissue)

• Optical effects

• Random errors

• Systematic influences

Pathology Laboratory

The role of computers in pathology

• Education (electronic textbooks)

• Research

• Making observations objective (morphometry,cytometry)

Number of mitosesSize and shape of nucleiSize and relative position of nucleoliChromatin patternDNA content and ploidyNucleus/cytoplasma ratioSurface measurementsAbsorption of chemical markers

Examples of Parameters in Cytometry

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Clinical Chemistry and Hematology

• Confirm a suspected diagnosis

• Monitor the effects of treatment

• Exclude or screen for the presence of disease

• Assess the prognosis once a diagnosis hasbeen made

Clinical Chemistry and Hematology

Schematic representation of subsystems operational in clinical chemistry

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Clinical Chemistry and Hematology

Schematic representation of tasks performed by a laboratory

information system during a test request cycle

Clinical Chemistry and Hematology

• Request processing

• Sample processing

• The preanalytical phase

• The analytical process

• Reporting

• Management information

• Electronic reporting of clinical laboratory test results

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Clinical Chemistry and Hematology

• Request processing– Mark-sense forms

• Sample preprocessing– Bar code

Clinical Chemistry and Hematology

• The preanalytical phase

• The analytical process

The process of first-line authorization in clinical chemistry

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Clinical Chemistry and Hematology

• Reporting

• Management information– GLP

• Electronic reporting of clinical laboratory test results– Health Level 7 (HL-7) standard http://hl7.org

– Euclides (European Clinical Laboratory Information DataExchange Standard)

• LIMS (http://www.lims.de )

Hospital Pharmacy

Care-related activities

• Keeping records of medication of patients

• Checking prescriptions

• Provide information concerning prescription of drugs andadministration

Logistic activitites

• Purchasing drugs

• Keeping stock

• Manufacturing drugs

• Distributing drugs

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Hospital Pharmacy

• Processes in hospital pharmacy

• Computer applications in the hospital pharmacy– Level 1: electronic communication

– Level 2: supporting logistics (stocks etc ...)

– Level 3: computation of drugs and optimal stock parameters

– Level 5: pharmacokinetic models, knowledge base

Hospital Pharmacy

• Basic functionality

Schematic overview of a task in a hospital pharmacy system