MIME encoding for PDF file

Does the code

set fi [open $fileName r]

  fconfigure $fi -translation {binary binary}

  set en64Var [encode [read $fi]]

  close $

just create a mime file?  I need to create an HL7 transaction that looks like this(below), need to know how to break up the mime into individual OBX segments. Is there a way to do this? Any help would be greatly appreciated.

MSH|^~&|COPATHPLUS|PPS_SC|4MEDICA|uon1|20081027123000||ORU^R01|500000000006|P|2.3

PID|1||02366688^^^uon1||LXROUNDIII^Two^C||19771121|F||W|6516 NEWPORT AVENUE^^OMAHA^NE^68154^United States||(402)559-8223|(402)559-8552|||||456-12-3456

PV1|1||OCUS||||||||||||||5710^Berg^Teresa|C|56659451|B||||||||||||||||||||||||200808280000

ORC|RE|129192022|S08-194^CoPathPlus||CM||||200809220851|^Gerken^Milissa||9117^Luckasen^John

OBR|1|129192022|S08-194_1|SR|||200809220849|||||||200809220849||9117||||||200809220852||SP|F||||||||^Gerken^Milissa

OBX|2|ED||1|Content-Type: text/plain; charset=US-ASCII; name=c:MimeTmime.pdf

OBX|3|ED||1|Content-transfer-encoding: base64

OBX|4|ED||1|

OBX|5|ED||1|JVBERi0xLjQNJeLjz9MNCjYgMCBvYmoNPDwvTGluZWFyaXplZCAxL0wgMzUw

OBX|6|ED||1|MzkvTyA4L0UgMzA5NDUvTiAxL1QgMzQ4NzMvSCBbIDY3NiAxNzhdPj4NZW5k

OBX|7|ED||1|b2JqDSAgICAgICAgICAgICAgICAgICAgDQp4cmVmDQo