Transcript Document

Applying HL7 in the
Acute Hospital setting
Philip Firth
IM&T Strategy Implementation Manager
Wrightington, Wigan & Leigh NHS Trust
[email protected]
Introduction

Look at some of the integration issues that
Acute Hospital NHS Trusts typically need to
address

Look at an example project with complex
interface needs – accident & emergency

Look at requirements for linking Acute
Hospital NHS Trust systems to LSP
solutions and the Spine
Acute Systems
Integration
Typical Issues
Issues …

Standards - what standards???

Implementation issues – PAS, Pathology
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Data quality
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Stylesheet issues
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TIME
Standards - what standards???

Interface standards/output formats in Wigan
– HL7 v2 (various implementations of)
– EDIFACT
– ASTM
– System specific output – eg. Torex PAS
openlink
 Acute
Trusts need to learn to work
with what’s available !!!
Implementation issues - PAS

PAS ‘real-time’ interface
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No guarantee that messages would be delivered in
the right order
– Could get an Admission message prior to a Patient
Registration
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Had to introduce a 15 minute time delay
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Result: bed-status in EPR system slightly out of sink
Implementation issues - Pathology

Handling previous results – append or overwrite?
– Microbiology – overwrite
– Haematology, Chemistry – currently append

Collection date and time not always supplied
 Reference ranges can change
– Implication for graphing
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Sensitive tests
– What is the best way to deal with HIV, GUM, pregnancy
tests etc?
Implementation issues - Pathology

Multiple patient IDs (NHS number, Hospital number)
 Multiple casenote numbers (Trust mergers)
– Need to establish systems for cross referencing patient IDs
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Missing patient ID
 Pathology system sending internal patient ID
 Missing key patient data – DOB, Gender
– Unable to guarantee a match – need to Dump message
Data Quality
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Biggest issue by far is unique person referencing
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Major education / change mgmt task to
– Get patient administration staff to register patient
details accurately and avoid duplicates
– Get clinicians to use the Hospital / NHS Number
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Problem especially big in emergency care
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Issue has a huge knock on effect for the
remainder of each episode care
Data Quality
Example:
A consultant asked me to investigate why a particular chemistry result
did not appear in the patient’s EPR record
In this instance the patient ID recorded in the Hospital Number field
turned out to be the patient’s telephone number
MSH|^~\&|MLAB||||20040519113446||ORU^R01|X99156|P|2.3
PID|1||217779^^^^PAS~773702^^^^DEP||SURNAME^FORENAME^^^||19371113|M|||999 ACACIA AVENUE^ORRELL^WIGAN^^WN9
9XX|||||
ZMP|G3417810^^NAT^SS^^L|^^L
ZPV|AE|CAS^^^MLAB&RAEI&L^^W|&AP^PINTO^A.^^^Mr.|CAS^^^MLAB&RAEI&L^^W|&AP^PINTO^A.^^^Mr.|ACC|CC|CH|20177803|2004
0519|200405191026||FITS.|U||P
OBR|1||20177803^CCMLAB|CC_RUEGK^Urea, Elects. Gluc
(urgent)^L^^^L|||20040519||||||FITS.|200405191026||&AP^PINTO^A.^^^Mr.||||||||CH|F||^^^20040519^S|
OBX|1|ST|CC_TONA^Sodium^L^44I5.^^RC||140|mmol/L|135-145|N|||F
Lesson: CANNOT use patient ID as the sole identifier – also need
to cross reference with patient’s DOB, Gender, Surname …
Addressing data quality
issues in Casualty
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Solution Integrated emergency floor system
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New emergency floor system is integrated with
PAS to enable staff to retrieve up-to-date patient
demograhics, including NHS Number
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New emergency floor Pathology / X-ray requests
automatically include patient ID
- improvement departmental system data quality
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New emergency floor system will be able to
automatically register new patients on PAS
- improvement 24 hour bed status
Addressing data quality
issues in Casualty
Integrated
emergency system
live
Patient ID data quality
Percentage requests
with valid patient ID
100
80
60
40
20
0
1.1.04
1.3.04
1.5.04
1.7.04
Time
1.9.04
1.11.04
Addressing data quality
issues in Casualty
Issues that are not so easy to address …
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Real-time data capture
– Not easy when an A&E receptionist is face to face with
a patient who is either
•
•
•
•
Confused
Uncooperative
Abusive
Unconscious
– Addressing these issues is proving to be a much more
challenging task!!!
Addressing presentation issues
using XSL Stylesheets
Rapid application development approach :
(1) Present the HL7 results in the EPR test system
environment via a stylesheet, and ask the
domain experts for comments
(2) Amend stylesheet, and repeat (1) until domain
experts are happy to sign off stylesheet design
(3) Implement stylesheet in live EPR system
Microbiology example - Legacy Pathology System view
Sensitivities in a
fairly non userfriendly cross
tabulation format
HL7v2 messages
A Culture and Sensitivity result is reported using multiple OBX segments.
A single organism result comprises an Organism OBX segment with subID N
followed by an Organism Growth OBX segment with subID N followed by zero, one
or more Organism Sensitivity OBX segments also with a subID value of N.
Microbiology
The final stylesheet
design was deemed
an improvement to
the legacy system
text based screen
More user-friendly
cross tab for
Organism vs
Sensitivities
Critical issue - TIME
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Building interfaces is not a 5 minute job
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Tasks
–
–
–
–
–
–
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Find funding to initiate project
Design interface, agree end-to-end requirements
Supplier set-up / configure interface
NHS Trust set-up / configure interface
End-to-end testing
On-going Stylesheet development
TIME
? (show-stopper?)
1-3 months ?
1-3 months ?
1-3 months ?
1-3 months ?
?
In summary, even a bog-standard unidirectional HL7 interface
could take anything from 3 to 15 months, from start to finish
Key benefit of basing your
integration architecture
around XML
EXCHANGE OF BOTH
DATA AND
PRESENTATION
Data and Presentation
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Web technology is enabling the Trust to
benefit from both
Data exchange: development of interfaces which
move XML patient data between an EPR (an
XML clinical repository) and other departmental
systems
Presentation: development and sharing of
stylesheets which present a common view of
departmental system data across multiple
applications
Data and Presentation
Discharge Letters,
Emergency Care summary
EPR
Electronic Patient
Records
Pathology results,
Patient demographics
JOIN
Example
Bi-directional
transfer of data
and presentation
between EPR
and A&E
Emergency Floor
Electronic Patient
Records
Shared XML data
and stylesheets
Haematology result
in the EPR system
Haematology result
in the A&E system
Addressing issues
and
Planning ahead for
HL7 v3 messaging
Emergency Floor system design
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Change management issues
– A&E clinicians had never previously entered clinical data into a
computer – all notes were recorded on a paper cascard
– Solution had to be QUICK and USER-FRIENDLY !!!
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Single screen to record all discharge information
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Order comms – all requests for investigations recorded
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Treatment given – point and click
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Drugs administered – point and click
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Diagnosis – point and click
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Clinician notes – free text
Emergency Floor system design
Simple / Quick point and click data capture
Emergency Care System
Emergency floor
system
Discharge screen
auto generates an
XML discharge
summary message
Stylesheets to
produce 2
documents on
discharge:
(a) Patient letter
(b) GP letter
Emergency floor discharge summaries
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Discharge summaries are currently stored in raw
XML and presented on screen using an XSL
stylesheet
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Diagnosis values are coded ICD10, but can easily
be coded in SNOMEDCT as well
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Raw XML can be transformed into valid HL7v3 A&E
Encounter and Provision of care messages using
XSLT prior to routing to the Spine
NPfIT Integration
Challenges
Existing Systems Integration
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Replacement of NHS IT systems will not
happen overnight in Acute Hospital Trusts
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Key department systems may not be
replaced before 2010
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Existing systems integration is therefore a
key issue for Acute Hospital Trusts
WWL / CSC NPfIT integration approach