Introduction

In HL7 it’s possible that you may have to deal with a legacy counter party system that has odd limits of the size of the messages they send. They might for instance be implemented using a mainframe system that can only cope with strings that 64k or less.

This page shows you how to use Iguana to stitch these parts together to make a single message.

Note: This solution assumes that messages are broken into two parts, and will need to be adapted for messages with more parts.

Before You Start

Part of the HL7 standard covers the ability to break larger messages containing say lab data, into smaller parts which then have to concatenated together by the receiving system.

How It Works

Here’s an example of the first part of the message where the presence of a DSC segment indicates that more data is to follow:

MSH|^~\&|SOFTMED^DIS|MGH|EGATE||20101110061841||MDM^T04|101110061841784|P|2.3.1||
EVN|
PID||1234567^^^MGH|||SMITH^THEODORE^E^^^^L^A||19350212|M||||||||||||
PV1|||W12^W1236^B||||018840|075325|||||||||018840|||||||||||||||||||||||||||20101025|20101103|
TXA|1|DIS||201011101818||201011030000|201011031346||018840||DEX|1307506|||||LA|||||^201011101818|
OBX|1|FT|&ZCR||DISCHARGE SUMMARY.br.brNAME: SMITH THEODORE E                   UNIT NUMBER: 123-45-67.br                                          FLOOR: W12 W1236B.brADMISSION DATE: 10/25/2010                DISCHARGE DATE: 11/03/2010.br.br.br.br.brPRINCIPAL DIAGNOSIS.brAVM.br.brASSOCIATED DIAGNOSES.brAltered mental status, Abnormal gait, Seizure disorder, Respiratory.brinsufficiency, Aphasia, Edema, Headache.br.brOPERATIONS AND PROCEDURES.br10/25/10: PROCEDURE: Left temporal craniotomy with microsurgical.brresection of arteriovenous malformation using BrainLab stereotactic.brguidance. Post-operative cerebral angiogram..br.br.brALLERGIES.brHCTZ (Unknown).brHeparin (Severe bleeding).brAspirin (severe bleeding).brALFUZOSIN (Unknown).brAMINOCAPROIC ACID (rhabdomyolysis).brALTEPLASE (severe bleeding).br.br.brHISTORY AND REASON FOR HOSPITALIZATION AND SIGNIFICANT FINDINGS.brThe patient is a 76yoM in for elective craniotomy for clipping of.brarteriovenous malformation with Dr. Ogilvy..br.brHPI: The patient has a complicated medical history including a h/o.brhereditary hemorrhagic telangiectasia (HHT) c/b cerebral, GI and.brpulmonary AVMs, chronic GIB, and progressive dyspnea. He is s/p.brBillroth II, duodenal resection for bleeding AVMs 6/19/2009 and s/p.brcoil embolization of left occipital artery to external jugular vein.brshunt vessel on 9/14/2010. He is transfusion dependent with chronic.brmelena/BRBPR and s/p cerebral bleed with resultant seizure. Pt. now.brpresents for surgical intervention for a temporal arteriovenous.brmalformation..br.brExam on admission:.brBP: 163/78 mm Hg.brAP: 95 bpm.brO2 Sat: 99%.brTemp: 97.8.brResp: 18.brHt: 66 inches.brWt: 153 lbs.brGeneral:  Patients is a well appearing, well nourished male in no.brapparent distress..brSkin:  Warm and dry to touch.  No sores, lesions, rashes, bruising or.brpetecchiae noted..brHEENT: Normocephalic, face symmetricalADD|
DSC|MGH-SM-1307506-20101110061841-1

This is the continuation part which indicates that it is a follow on message by having the continuation ID in it’s MSH message header segment:

MSH|^~\&|SOFTMED^DIS|MGH|EGATE||20101110061841||MDM^T04|101110061841784|P|2.3.1||MGH-SM-1307506-20101110061841-1
ADD|until cleared by this MD at follow-up.\.br\\.br\\.br\||||||S|||201011031346|
PR1||||||
ZTR|||||SOFTMED|MGH||||DE^DEX Discharge Summary^MGH-RPTL-REPTYPE|This article has not been written.

The example in the following three pages explains how to leverage the Translator to solve this problem.

The code for this example is effectively “plug and play” as it will automatically create its own SQLite database and tables if they do not exist.