implementation of web services based electronic medical record
DESCRIPTION
Implementation of Web Services Based Electronic Medical Record. Kevin W. McEnery, M.D. Charles T. Suitor, M.S. U.T. M. D. Anderson Cancer Center Houston, TX. Web Services EMR. Why web services Advantages over traditional EMR Review implementation Current status Discuss technical details - PowerPoint PPT PresentationTRANSCRIPT
Implementation of Web Services Based Electronic
Medical Record
Kevin W. McEnery, M.D.Charles T. Suitor, M.S.
U.T. M. D. Anderson Cancer CenterHouston, TX
Web Services EMR Why web services
Advantages over traditional EMR Review implementation
Current status Discuss technical details
Security, scalability National Health Information
Infrastructure and WS Questions
EMR Project overview
Legacy systems were on a variety of platforms No single access method could
retrieve all the data we needed. The technical solution had to be
affordable, and we had to be able to implement it quickly.
Traditional EMR Model Limitations
Institutional Data Model may not easily map into EMR vendor’s data model Legacy systems have an inherent data structure EMR have their own data structure These may be incompatible
EMR application workflow does not easily mesh with institution’s workflow EMR application customization$$$$$$ Institutional training session$$$$$ Long project delay$$$$ Numerous failure example$$$$$$$
Institution’s strategic decision
Departmental systems best meet the needs of the business unit
System selection not biased toward EMR Radiology – Siemens RIS, Stentor PACS Pathology – Tamtron Laboratory – Cerner Operating room – PICIS Pharmacy – GE BDM
Web Services Enterprise EMR
implementation? Scalability? Security? Institutional support
requirements?
“I ask Congress to move forward on a comprehensive health care agenda… improved information technology to prevent medical errors and needless costs…”
George W. Bush, State of the Union, 2005
Each folder is web service Allergies Reports
Radiology Laboratory Pathology
Images Pharmacy Cardiology OR Schedule Clinic Schedule Hospital Census
Radiology Information
System
Conventional System Architecture
“Monolithic Application”
RIS Application
Pathology Information
System
Pre-OP RecordsSystem
Scanned Documents
Pharmacy System
Hospital Information
System
PACSEchocardiologySystem
TranscribedDocument
System
`
Radiology Information
System
Laborartory Information
System
VitalSigns
Central Data Repository
EMR Application
“Traditional EMR” “Monolithic Application”
Web Services Implementation
Multiple clinical data sources already existed Level of enterprise availability varies
e.g. Pharmacy system allergy data Legacy systems address needs of owners
“Best of breed sub-systems” RIS, LIS, anatomic pathology…
Single vendor solution unlikely Single legacy system contains official result
Radiology report in RIS Path reports in pathology system
XML
ClinicStationClinicStation
`
Pathology Information
System
Pre-OP RecordsSystem
Scanned Documents
Pharmacy System
Hospital Information
System
PACSEchocardiologySystem
TranscribedDocument
System
Radiology Information
System
Laborartory Information
System
VitalSigns
Clinical Data Repository“Clinical Source Documents”
Legacy System Database Stores Clinical Data
Clinical documentationentered directly into legacy system by clinician
Automatically availablethroughout the enterprise
Application Tier
Client Tier
Web Services Architecture
Network
Network
Pathology Information
System
Pre-OP RecordsSystem
Scanned Documents
Pharmacy System
PACSEchocardiologySystem
Radiology Information
System
VitalSigns
Hospital Information
System
TranscribedDocument
System
Laborartory Information
System
Clinical Data Repository“Clinical Source Documents”
Clinical Documentation
Patient Interaction
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Patient Interaction
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Patient Interaction
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Review Last Interaction Review Last Interaction
Limitations of “traditional” clinical data
Much clinical data non-structured Dictated clinical notes Handwritten clinical notes Medical images
Limited information regarding image content No current accepted, or legislated,
standard regarding structured clinical data Exception: Pathology, Mammography
Limited capability to automatically share clinical data across enterprise
Standardization of clinical data
Recorded at the appropriate level of detail
Consistent over time and across boundaries
Transmitted without loss of meaning Aggregated at more general levels and
along multiple different perspectives Interpreted by automated systems
Modified from SNOMED Overview – American College of Pathologists
Allergy
Medications Listing
Review of Systems
Height Weight - Vital Signs
MRI Checklist
Surgical History
MRI Experience
Signature and Authentication
Patient Demographics
DI Exam Patient Checklist Data
Pain Symptoms – Vital Signs
Diabetic History
Pregnancy -Breast Feeding
Patient Demographics
Height Weight
Vital Signs
Review of Systems
Allergy
Redundant Clinical Information
Allergies Family History Medical/Oncology History Surgical History Current Medications ROS Patient problem list
Trend – Structured Documents
XMLXML
Store DataStore Document
AllergyWeb Service
Review of SystemsWeb Service
Medication
Web Service
Clinical Web Services Allergies Family History Medical/Oncology History Surgical History Current Medications ROS Patient problem list
Redundant Clinical Information
Web services: Beyond EMR Patient Schedule
ClinicStation myMDAnderson.org Patient kiosks Electronic whiteboards
Diagnostic Imaging (8) Emergency Center
Web Services: Unlocking data
Radiology Information
System
RIS Application
RadiologyReports WS
DI Patient Tracking WS
ProcedureComments WS
Patient Schedule WS
Emergency Center Web Services
ER ActivityDigital Whiteboard(viewable in ICU)
ER Room CensusDigital Whiteboard
DataSource
XML-based web service
Rules Tier
Client Tier
XML
XSL
HTTP
Web Services: XML data
Distributed clinical architecture
Services-based architecture provide a standard method to access and update clinical data Numerous applications possible
Structured data flows to client XML
Client formats and interacts with data for display
Structured data flows to server XML
Will it scale?
Instant access to clinical information >100 transactions/second >1,200,000 patient queries per month
>50M audit event per month
6,197 computers 52.2 million
transactions/month
5,753 users 1,073 physician users
Web Services Architectures
Multiple Web Services # Web Services = # Functions
Single Web Service 1 Web Service Many Functions
Building Web Services
Clients call functions via a web server
Examples GetRadiologyReport(Accession)
GetLabProcedures(MRN)
Building Web Services
Each Web Service must have several features Security Auditing Maintainability Specific business logic
Building Web Services Solve the common problems
once Provide a single Web Service that provides
Security – most likely a session Auditing – in and out available Dispatching to work components
Building Web Services Individual functions can be
components (i.e. GetRadReport) Business logic only, no security or
auditing Each function/component can be
independently updated and monitored
Monitoring Components
Characteristics of Components
Stateless Especially important for server farms
Short execution time Keeps simultaneous execution down
Characteristics of Components
Single Function per Component Easier to maintain & update
Designed for multiple instances executing simultaneously Proper threading model No shared resources
MDACC Server Configuration
10 server farm, load distributed, via hardware network load balancer
Each server is dual processor, 2GB RAM, Win2K Server Commodity pricing Robust performance
MDACC Performance Data collected every 5 seconds
over a 24 hour period
Executing
Req/sec
CPU % Connections
Average 14 35.3 2.45 903
Max 149 162.2 18.8 2778
Min 1 4.0 0.08 29
Web Services Web Services aren’t magic Web Services systems only scale
if they are designed to scale We have encountered a commercial
Web Services HIT system with limited throughput
10 simultaneous queries, 3 sec/query
Integration
Capabilities of legacy systems need to be considered
Underpowered systems can be protected with a cache Query based cache HL7 replication based cache
Web Services EMR Web-services can provide a
method for universal access to clinical information already available in legacy systems Alternative to centralized archive Best of breed legacy sub-
systems
Web Services Enterprise implementation?
Yes and growing… Can it scale?
1.2M patient queries/month Are they secure?
Yes and meet HIPAA audit requirements What are institutional support
requirements? Minimal day to day Leverage existing institutional
investment
