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Architectures of Hospital Information Systems
Introduction
After having introduced health information systems in general we will at first turn
our attention to hospital information systems
We now take a closer look at what hospital information systems look like. We will
do that rather synthetically, meaning:
–we will first look at all the detailed components a hospital information system consists
of,
–and then we will explain how these components can be synthesized, i.e. assembled in
order to achieve that what users nowadays experience as the hospital information
system
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Architectures of Hospital Information Systems
We start discussing the kind of data, which has to be processed in hospitals and
then present hospital functions interpreting or updating these data
We introduce typical information processing tools and typical architectures first at
the logical and then at the physical tool layer of hospital information systems.
At each layer we explain how these tools can be assembled and integrated for the
better support of users
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Architectures of Hospital Information Systems
After this lecture, you should be able to answer the following questions:
–What kind of data has to be processed in hospitals?
–What are the main hospital functions?
–What are the typical information processing tools in hospitals?
–What are the different architectures of HIS?
–How can integrity and integration be achieved within HIS?
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Architectures of Hospital Information Systems
Domain Layer: data to be processed in Hospital
Entity types related to Patient Care (examples)
Typical entity types representing certain object classes and data related to the
patient and his or her histories:
Entity type Descriptor of an instance of the represented object class
Case mostly comprises a patient‟s stay in a hospital from patient admission to
patient discharge or several ambulatory treatments related to one disease;
information about a case includes the case identification number (CIN
Patient is a person being subject of care; information about a patient includes the
patient identification number (PIN)
Order is a request for a diagnostic, therapeutic or drug service, e. g., a laboratory
order or a radiological order
Diagnosis is the identified cause or nature of a disease or medical condition
Note: we can express „kind of data‟ by entity types
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Architectures of Hospital Information Systems
Entity types related to Resources (examples)
A hospital must guarantee that all resources needed for patient care are available
continuously. The following resources are necessary:
Entity type Descriptor of an instance of the represented object class
Appointment determines what persons have to be at a certain place at a given time.
Examples are appointment for patient admission, examination or surgery.
Bed must be managed according to its occupation.
Health care
professional
a health care professional who treats according to his or her specialization (e.
g. nephrology or pediatrics) patients with certain diagnoses. Health care
professionals are for example physicians and nurses.
Drug is a substance administered to a patient for treatment, diagnosis or
prevention
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Architectures of Hospital Information Systems
Entity types related to Administration (examples)
Besides information about resources, hospital administration needs the following
entity type:
Entity type Descriptor of an instance of the represented object class
Patient record
archive
describes how and where the electronic or paper-based patient record can be found.
Classification consists of a set of classes summarizing concepts not to be distinguished during analysis.
Classification of
diagnoses
e. g. the International Classification of Diseases (ICD).
Cost unit information about a person or an institution responsible for bearing the costs or a part of
the costs for the services to be provided
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Architectures of Hospital Information Systems
Entity types related to Management (examples)
Management relates to the hospital as a whole and, thus, needs compressed
information about the hospitals‟ operating. The following entity types are
necessary for management:
Entity type Descriptor of an instance of the represented object class
Business strategy defines the hospital‟s long-term strategic goals
Strategic
information
management plan
a strategic plan, which gives directives for the construction and development of a hospital
information system
Project a unique undertaking that is characterized by management by objectives, by restrictions
with regard to available time and resources, and by a specific project organization (DIN
69901)
Quality report openly published report about a hospital‟s performance
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Architectures of Hospital Information Systems
Domain layer: Hospital Functions
We will now elucidate, how and where data about these entity types are
processed in hospitals.
We use enterprise functions to summarize classes of information processing
activities.
And since we focus on hospitals, we call them hospital functions here, which can
also be considered as representatives of processes
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Architectures of Hospital Information Systems
We will present hospital functions and their interpreted and updated entity types
in greater detail, but we do not (yet) focus on how they are typically supported by
various computer-based or non-computer-based information processing tools
We will focus on the following questions:
–What are the main hospital functions that have to be supported by a HIS?
–What information is interpreted or updated by hospital functions?
–Which functional aspects have to be considered when implementing information
processing tools?
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Architectures of Hospital Information Systems
Main enterprise function to be supported by a HIS:
–Patient care
–Supply and disposal management, scheduling and resource allocation
–Hospital administration
–Hospital management
–Research and education
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Architectures of Hospital Information Systems
Patient care:
–Patient admission
–Decision making, planning and organization of patient treatment
–Order entry
–Execution of diacnostic, therapeutic and nursing procedures
–Coding of diagnoses and procedures
–Patient discharge
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Architectures of Hospital Information Systems
Patient admission:
Patient admission (short: admission) aims at recording and distributing the
patient demographics and insurance data as well as medical and nursing data
of the patient history
In addition, each patient must becorrectly
identified, and a unique patient and case
identifier must be assigned
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Patient admission
This hospital function can be decomposed as follows:
–Appointment scheduling
–Patient identification and checking for recurrent
–Administrative admission
–Medical admission
–Nursing admission
–Visitor and information service
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Apointment scheduling:
The hospital must be able to schedule an appointment for a patient's visit. In
addition, unplanned patient admissions must be possible
(e.g., in case of emergencies)
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Architectures of Hospital Information Systems
Patient identification and checking for recurrent:
A unique patient identification number (PIN) must be assigned to each patient:
–This PIN should be valid and unchangeable lifelong (i.e., the PIN should not be based on
changeable patient‟s attributes such as the name)
–The PIN is the main precondition for a patient-oriented combination of all information arising
during previous, recent as well as future hospitalizations
Before a PIN can be assigned, the patient must be correctly identified, usually based
on a health insurance card and on available administrative patient master information
(such as name, date of birth)
…..
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Architectures of Hospital Information Systems
If the patient has already been in the hospital, she or he must be identified as
recurrent, and previously documented information must be made available (such
as previous diagnoses and therapies).
If the patient is in the hospital for the first time, a new PIN must be assigned.
In addition, the hospital must be able to distinguish different cases or hospital
stays of a patient. Therefore, in addition to the PIN, a case identification number
(CIN) is usually assigned (see administrative admission).
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Administrative admission:
Administrative admission starts following patient identification. It creates a so-
called case, being the aggregation of several contacts, clustered according to
specific clinical and/or organizational purposes of the hospital
In case of inpatient treatment, a case summarizes the hospital stay from patient
admission until discharge
Each case is uniquely identified by its CIN. Important administrative data such as
insurance data, details about special services, patient's relatives, admitting
physician, and transfer diagnoses must be recorded
…..
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Architectures of Hospital Information Systems
Some of the administrative data must be available to other hospital functions
through the help of certain organization media. Administrative data form the
backbone of information processing
In case of changes, patient data must be maintained and communicated. If the
admitting physician has communicated relevant information (e.g., previous
laboratory findings), this information must be communicated to the responsible
physician in the hospital
…..
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Architectures of Hospital Information Systems
Administrative admission is usually done either in a central patient admission
area or directly on the ward (e.g., during emergencies or on the weekend)
Even in emergencies patient admission is necessary. At least patient identification
and checking for recurrent has to be performed in order to assign a proper PIN
and CIN. In these cases a short version of administrative admission may be
applicable
If the patient is unconscious and does not bear an identity card, only a dummy
name may be recorded to provide PIN and CIN. It will be no problem to replace
the dummy name by the correct name later
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Architectures of Hospital Information Systems
Medical admission:
The responsible physician will carry out the medical admission. This typically comprises the
patient history (disease history, systems review, social history, past medical history, family
history, medication). Some of this information may be collected from documents of the
referring physician and is taken to the hospital by the patient himself. Medical admission is
usually done on the ward
As a result of medical admission the admission diagnosis has to be stated and to be coded
according to ICD10
The basic patient history data have to be made available for other hospital functions. For the
patient history there may also be department-specific, (semi-) standardized data entry
forms available
The collected information should be available during the whole stay
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Architectures of Hospital Information Systems
Nursing admission:
The responsible nurse will proceed with the nursing admission. This typically comprises the
introduction of the patient to the ward and the nursing history. Nursing admission is usually
done at the ward
Administrative data and the reason of hospitalization are already at her or his disposal
For the nursing history there may be computer-based or department-specific, (semi-)
standardized data entry forms available. These may contain information about the current
diagnosis and therapy, orientation, communication ability, social contacts, nutrition,
mobility, personal hygiene, and vital signs
The collected information should be available during the whole stay
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Architectures of Hospital Information Systems
Visitor and information services:
The hospital management must always have an overview of the recent bed occupation, i.e., about
the patients’ staying at the hospital.
This is, for example, important for the clerks
at the information desk, who must be able to
inform relatives and visitors correctly, and
also for some general hospital management
statistics
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Patient admission
.
Extract of the domain layer of the 3LGM² based reference
model describing the enterprise function patient admission, its
subfunctions and interpreted and updated entity types.
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Architectures of Hospital Information Systems
Patient care:
–Patient admission
–Decision making, planning and organization of patient treatment
–Order entry
–Execution of diacnostic, therapeutic and nursing procedures
–Coding of diagnoses and procedures
–Patient discharge