		USERS GUIDE: STELPUMP version 1.05.

JF Coetzee and R Pina, July 1996

		USER'S GUIDE: STELPUMP version 1.05 

Johan Coetzee and Ralph Pina, August 1996.

                       CONTENTS
    
    Notice:   Registration.

    Preface:  Differences between Stelpump versions 1.0 and 1.05.

1.  Introduction
2.  What you need to run Stelpump
3.  Stelpump quickstart
4.  Running Stelpump
	   4.1 Stelpump's three screens
	   4.2 Opening screen (Screen-1)
		   4.2.1  Speed
		   4.2.2  Files
		   4.2.3  Path
		   4.2.4  Infuse or Simulate 
5.  Drug and administration profile (Screen-2):
	   5.1  Introduction
	   5.2  Help window
	   5.3  Drug name 
	   5.4  Infusion regimen
	   5.5  Pharmacokinetic parameter set (PK Models)
	   5.6  Pump types
	   5.7  Target concentration 
	   5.8  Maximum plasma concentration 
	   5.9  Syringe type 
	   5.10  Syringe size
	   5.11  Syringe concentration
	   5.12  Volume present 
	   5.13  Saving a profile file 
	   5.14  Confirm your entries and proceed to Screen-3

6.  Administering infusions (Screen-3):
	   6.1  Help window 
	   6.2  Information displayed infusions 
	   6.3  Administering infusions
		   6.3.1  Starting and stopping an infusion 
		   6.3.2  F5 (Change) 
		   6.3.3  F6 (Info)
		   6.3.4  F7 (Scroll pump rate units) 
		   6.3.5  F8 (Scroll infusion rate units) 
		   6.3.6  F9 (Adjust the Y-scale) 
		   6.3.7  F10 (Change the date and time) 
7.  Some practical considerations
	   7.1  First-time users
	   7.2  An "empty" syringe in simulation mode 
	   7.3  Starting in bolus-and-constant-infusion mode 
	   7.4  Alarm conditions
	   7.5  Notable properties of some pumps 
	   7.6  Scources of inaccuracy
 
8.  .LOG files
9.  Cable connections for various pumps:
10. References  
11. Registration

 
NOTICE: REGISTRATION:

Stelpump is provided free of charge as an educational and 
experimental device.  The authors request all users of Stelpump 
to register with us so that we may send you updates, keep you 
informed of new developments, problems etc.  A registration form 
is presented at the back of this manual and we urge you to send 
the completed form to:

Dr J.F. Coetzee
Department of Anesthesiology
Faculty of Medicine
University of Stellenbosch
P.O. Box 19063
7505 Tygerberg
South Africa

If you have downloaded Stelpump from the Internet, you will find 
a file containing the registration form (REGISTER.ASC) which you 
may fill out and send via E-Mail to jfc@maties.sun.ac.za 
PREFACE TO VERSION 1.05:

There are some notable changes between Stelpump version 1.0 and 
version 1.05:

1. Stelpump now uses extended memory and requires that the device 
   drivers HIMEM.SYS and EMM386.EXE  be loaded into memory at 
   startup by the CONFIG.SYS procedure.  In addition, the 
   following files need to be present in the same directory in 
   which STELPUMP.EXE is placed:  DPMI16BI.OVL and RTM.EXE.  We 
   recommend that that you have a total of 4 MB of RAM memory, 
   however we have found that Stelpump version 1.05 appears to 
   run satisfactorily with only 2 MB of RAM present.

2. You now have the facility to enter your own pharmacokinetic 
   (PK) parameters using .PKM files (see section 4.2.2).

3. Most laptop/notebook computers are now supplied with only one 
   serial communications port and an expensive option is to 
   install an extra port in the modem slot or the PCMIA slot.  
   Stelpump v1.05 now includes drivers for the 2-channel Baxter 
   6301 and the  Imed Gemini PC-2  volumetric pumps with  the 
   advantage that two pumps ("Channels" A and B) can be 
   controlled using only one serial port.  Remember that both 
   channels must be controlled from the SAME port. 

4. Several "bugs" have been identified in version 1.0 and 
   corrected.  It is recommended that you replace version 1.0 
   with version 1.05.  
   
   5. Please note that "Profile" files (with extension .PRO) created 
   with version 1.01 will cause Stelpump version 1.05 to act 
   differently.  So you must re-create your old profile files on 
   converting to version 1.05.
   
1.  INTRODUCTION:

STELPUMP has been developed through collaboration between 
anaesthesiologist, Johan Coetzee and professional electronics 
engineer, Ralph Pina, both of the University of Stellenbosch, 
South Africa.  The program is intended for   clinicians who have 
minimal familiarity with Microsoft "DOS" or IBM PC-DOS compatible 
personal computers and who  have a basic knowledge of the MS-DOS 
operating system.  STELPUMP controls up to two infusion pumps via 
the computer serial ports.  The user may target plasma or effect-
site concentrations, or administer continuous infusions.  
Expected concentrations are displayed in digital and graphical 
format.  The algorithms employed in this program include those of 
Steven Shafer [1] to target the plasma concentrations and Jim 
Jacobs [2] to target the effect-site concentrations. The program 
was written in Borland's Turbo Pascal by Ralph Pina.  

Acknowledgement is given to Dr. Steven Shafer's program STANPUMP 
which influenced the information displayed onscreen and the 
choice of pharmacokinetic models.   One of the reasons for 
developing STELPUMP was to provide a library of pumps so that 
physicians would be able to use whatever apparatus is available 
to them in their particular institutions.  At present the 
following  pumps are provided for (Version 1.05): Harvard 22, 
Graseby 3400, IVAC P4000, Braun Perfusor Secura, Baxter 6201 and 
6301, IMED Gemini.


The program is distributed free of charge in order to provide 
clinicians with an educational tool and to encourage dosing 
according to pharmacokinetic and pharmacodynamic principles.  In 
particular, the simulation mode should provide users with a 
"feel" for a drug.  Those who are not familiar with target-
controlled infusions are encouraged to read section 7, "Some 
Practical Considerations".

It is hoped that users will find the program user-friendly and 
flexible for use in clinical environments and the authors would 
appreciate comments and suggestions for further improvement.  In 
particular, it is important that you should make us aware of any 
mistakes or "bugs" that may be lurking in the program.  

CAVEAT EMPTOR:
STELPUMP has been written to run under the MS-DOS operating 
system.  It is not recommended that you run the program in a 
simulated multitasking environment such as Microsoft Windows or 
Deskview as other programs running in the background will slow up 
the program considerably leading to inaccurate infusions.   
STELPUMP has not been tested in a true multitasking environment 
such as IBM's OS-2, or Microsoft's Windows 95.

The authors wish to advise users that STELPUMP has not been 
approved as a medical device by a regulatory body in any country.  
It should be used for experimental purposes only, under the aegis 
of the user's institutional ethics committee. 

 
2.  WHAT YOU NEED TO RUN STELPUMP:

Computer: 486DX or better. 
Graphics card: VGA card with colour VGA monitor (preferably), or 
                monochrome VGA monitor.

Memory: 4 MB RAM memory configured as extended memory with the 
	 DOS memory managers HIMEM.SYS and EMM386.EXE loaded.

Operating system: MS-DOS 5.0 or later. 

Cable: connected up correctly between pump and the computer's 
       serial communications port.  (See appendix for the various 
       cabling interconnections).  No cabling is necessary to run 
       simulation mode.

Compatible infusion pump(s)
3.  STELPUMP QUICKSTART:

At the DOS prompt enter STELPUMP.
You will progress through three "screens".
Screens-1 and -2 are for preparation. 
Screen-3 is displayed during the actual infusion/simulation.

Screen-1 (opening screen)
   
   1.1  Decide on whether you wish to administer an infusion or 
	 perform a simulation. 
   
   1.2   If you wish to perform a simulation select Speed.
   
   1.3. Decide on whether you wish to log calculated 
	 concentrations etc. to disk.  If so select "Files" and 
	 enter the .LOG filename.
   
   1.4. If you have already saved .PRO files you may wish 
	 to select a "work profile" in the "Files" menu.  
	 Otherwise proceed to 1.5.
   
   1.5. Select either "Simulate" or "Infuse"
   
   1.6. Choose 1 pump or 2 pumps.


Screen-2 (Patient and drug administration profile):
   
   Observe the Function Key menu at the bottom of the screen 
   
   2.1  Enter patient mass, age, sex.
    
   NOTE: If you have already loaded a "Profile"  (.PRO) file, 
   steps 2.1 to 2.10 may be omitted as the information is already 
   there, in which case, press F9 (Confirm) and proceed to 
   Screen-3.
   
   
   2.2  Select drug(s) (F5)
   
   2.3  Select infusion mode(s) (F5)
	(target plasma/effect-site or constant infusion). 
   
   2.4  Select PK model(s) (F5)
   
   2.5  Select pump type(s) (F5)
   
   2.6  Enter the target concentration(s) (target mode).
   
   2.7  Enter the maximum allowable plasma concentration(s).
   
   2.8  Select syringe type(s) (F5)
   
   2.9  Select syringe size(s) (F5)
   
   2.10 Enter the concentration(s) of drug(s) in the syringe(s).
   
   2.11 Enter the volume(s) of drug(s) present in the syringe(s).
   
   
   Press F9 (Confirm) and proceed to Screen-3.


Screen-3: (Administer the infusion) 
   
   Observe the Function Key Menu at the bottom of the screen.
   
   One pump:
       
       If you are using only one pump, press F2 (Start).
   
   Two pumps:
       
       If you are using two pumps, select the first pump to start 
       by pressing F1.  Note that the background colour of the 
       function key menu coincides with the background colour of 
       the relevant pump's screen.
       
       Start the first pump by pressing F2
       
       Select the second pump (F1).
       
       Start the second pump (F2). 
   
   Pump control is further effected by pressing the function keys 
   specified in the Function Key menu at the bottom of the 
   screen.
   
   NOTE: 
   "Dark" coloured function keys are concerned with actual 
   control of the pump(s). 
   
   "Light" coloured function keys provide or manipulate 
   information.


4.  RUNNING STELPUMP:

4.1  STELPUMP'S THREE "SCREENS":

There are three "screens" in STELPUMP.  On starting the program, 
you will be presented with the opening screen ("Screen-1").  
After requesting an infusion or a simulation, you progress to 
"Screen-2" ("Patient and drug administration profile").  Here, 
you select the drug, pharmacokinetic model, pump type, targeted 
concentrations etc.  You may return to Screen-1 from Screen-2 and 
back without losing information.  After confirming your 
selections, you progress to the infusion screen ("Screen-3").  
You may then begin the infusion(s).  During the infusion(s), the 
expected concentrations and other important information are 
displayed continuously in digital and graphic format.


4.2  OPENING SCREEN (SCREEN-1):

Move the cursor along the main menu at the top of the screen 
using the arrow keys and bring up the submenus by pressing the 
enter key.  You may exit a submenu without making any changes by 
pressing Esc.  Make selections by pressing enter or typing in the 
relevant information as requested and pressing enter.    

You may choose between performing a simulation or administering 
an infusion.  The speed of the simulation may be set by first 
selecting "Speed" from the main menu.  

4.2.1  "Speed" provides you with three choices:

Set Delta T: Infusion pumps  are capable of  delivering constant
	       infusion rates only.  In a pharmacokinetically 
	       target-controlled system the infusion rate needs 
	       to change continuously, so a compromise is 
	       acheived by updating the pump's infusion rate at 
	       short intervals (Delta-T).  Delta-T is also the 
	       time used by the program to calculate the 
	       patient's expected drug concentrations using 
	       Euler's method of numerical integration [1].  The 
	       default for Delta-T is 10 seconds and has been 
	       found to be adequate for most drugs used in 
	       anaesthesia.  It is unlikely that you will need to 
	       change the value for Delta-T.  Increasing Delta-T 
	       will increase the simulation speed but introduce a 
	       slightly greater error in both the simulation- and 
	       the infusion- modes. 

Simulation: Normal Speed:  The simulated drug infusion will occur 
					  in real-time. 

Simulation: Speed Up:  The simulated drug infusion will occur at 
		       at a rate where Delta-T is compressed to 
		       one second: i.e. the accelerated simulation 
		       will occur 10 times faster than a 
		       simulation in real time if Delta-T is 10 
		       seconds.
4.2.2  Files: 

STELPUMP uses three types of files: "Log" files, "Profile" files 
and "PK Model" files. 
   
   "Log" files: 
       
       STELPUMP will write all calculated concentrations, pump 
       speed, alarms and other activities to a disk file (See 
       section 8 for more detail).  "Log" files will only be 
       written to if requested and named in this screen (Screen-
       1).  Enter the name of the file (maximum eight 
       alphanumeric characters) The program adds the 
       extension .LOG automatically.  You may disable the logging 
       function by selecting "Cancel Log". 
   
   "Profile" files:
       
       "Profile" files save the user a great deal of time and 
       trouble by saving a work "profile".  The file contains the 
       information that you would normally enter in the next 
       screen (Screen-2) i.e. the drug name, pharmacokinetic 
       model, targeted concentration etc.  So, if you have a 
       certain routine way of working, you may read the details 
       from the .PRO file on disk, thereby saving yourself the 
       trouble of having to enter the information manually every 
       time you use STELPUMP.
       
         You create a Profile file by first entering the relevant 
       information in Screen-2 (see section 5, entitled "Patient 
       and drug administration profile: Screen 2").  You then 
       return to Screen-1 (by pressing F4) to save the 
       information to a "Profile" file.  Enter the name of the 
       file (maximum eight letters).  The program adds the 
       extension .PRO automatically.  You may enter any number of 
       profile files which are then saved on the disk and may be 
       read from the startup screen.
       
       You may also save a profile file after having completed 
       an infusion, as the information is not lost after 
       "aborting" an infusion and returning to the opening 
       screen. 
       
       NOTE: After you have selected/entered the desired Profile 
       and Log files, their names, as well as the data path, are 
       displayed  at the bottom left portion of Screen-1. 
       
       Please note that "Profile" files (with extension .PRO) 
       created with version 1.01 will cause Stelpump version 1.05 
       to act differently.  So you must re-create your old 
       profile files on converting to version 1.05.
    
   "PK Model" files:
       
       Stelpump version 1.05 enables you to input your own 
       pharmacokinetic parameters for the drugs listed in the 
       drug library.  This is done by entering your PK parameters 
       into a text file (ASCII file) that has the extension 
       ".PKM".  The file may be created using any word processor.    
       The syntax of these files must be correct, or else an 
       error message will appear when you attempt to read them 
       into memory.  Save the document to a text-file  giving it 
       the extension ".PKM". 
       
       
       The following template can be used and is provided in the 
       file "TEMPLATE.PKM":

$                     (comments)
Name=__________       (Model name, max 10 chars,
Drug=propofol         (1 word, spelling must be correct)
mass=TRUE             (TRUE : massxV1; FALSE: mass not required)
V1=nn.nnnn            (in litres)
k10=n.nnnn            (in /min, enter 0 if not used)
k12=n.nnnn
k21=n.nnnn
k13=n.nnnn
k31=n.nnnn
keo=n.nnnn

(Note: no spaces allowed between parameter name, '=' and parameter value;
       and no meaningless lines, except after "keo=" !)

A typical .PKM file for your own PK parameter set is illustrated 
by the following set for 25 kg pigs from our laboratory:

$ PK model for propofol in pigs.
Name=pigpropof       
Drug=propofol        
mass=FALSE            
V1=2.97        
k10=0.257   
k12=0.5264
k21=0.2380
k13=0.3106
k31=0.01744
keo=0

If you load this file into Stelpump from Screen-1 and you select 
propofol as the drug to be infused from Screen-2, you will see 
that the above PK set will have been added to the available list 
under the name "pigpropofol".  

If you wish, you can leave the bracketed text in TEMPLATE.PKM 
intact.  Here is a PK model for alfentanil in 25 kg pigs that 
will load into Stelpump:

$ Pig (25 kg) alfentanil PK model             (comments)
Name=PIGALFENT       (Model name, max 10 chars,
Drug=alfentanil      (1 word, spelling must be correct)
mass=FALSE           (TRUE : massxV1; FALSE: mass not required)
V1=1.384            (in litres)
k10=0.36            (in /min, enter 0 if not used)
k12=0.4542
k21=0.12238
k13=0
k31=0
keo=0

(Note: no spaces allowed between parameter name, '=' and parameter value;
       and no meaningless lines, except after "keo=" !) 
   
   Having created and saved your own .PKM files, you load them 
   into Stelpump as follows:  Select "Files" in Screen-1 and then 
   select "Load PKModel".  A list of the available .PKM files 
   appears which you may select by moving the cursor and pressing 
   Enter. A maximum of 10 PK-models may be loaded successively.  
   Do not try to load more than 10 because there is no error-
   checking to prevent you from trying to load more.  When you 
   enter Screen-2, the PK model that you have entered into 
   the .PKM file will be available from the library of PK models 
   (see section 5.5).
   
   
4.2.3  "Path": 
   
   You may specify the DOS file-directory in which the .PRO, .LOG 
   and .PKM files are stored.  The default is the directory in 
   which the  program file STELPUMP.EXE is to be found.


4.2.4  Infuse or Simulate: 
   
   Choose between one and two pumps.  You will then be presented 
   with Screen-2
 

5.  Patient and drug administration profile:(SCREEN-2)  

5.1  Introduction 

At the top of the screen is a grey-coloured window into which you 
enter the patient details (body mass, age and sex).  The cursor 
will jump to the next required item of information as you enter 
the details and will then move into the (blue) pharmacokinetic 
(PK) window automatically.  You may also move between items by 
pressing the up- and -down arrow keys.  Switch patient sex by 
pressing F5 (Change Entry).

5.2  Function Key window:

At the bottom of the screen is a help window, indicating the 
purpose of the various function keys:

Summary of Function Key window for Screen-2:

F4: Return to the previous screen 

F5:  Change the present entry

F6:  Alternate between patient window and PK window.

F8:  Change infusion-rate units (in Constant Infusion mode).

F10:  Change the date- and time-display.

F9:  Confirm the entries and proceed to Screen-3.


5.3 Drug Name: 

The Drug Name appears at the top left portion of the window.  
Select the desired drug by pressing F5 (change entry) to obtain 
the built-in library of drugs.



5.4  Infusion Regimen: 

Select the infusion regimen by pressing F5 (change entry).  You 
may choose between targeting the plasma concentration or the 
effect-site concentration; or you may administer a bolus-and-
constant-infusion-rate dosage regimen.  If you choose the latter, 
select the units in which you wish to administer the constant 
infusion  by pressing F8 successively.  Available choices are: 

mg/h
mg/min
mg/kg/h
mg/kg/min

Note that certain drugs (e.g. sufentanil, fentanyl, alfentanil) 
are dosed in g units.

You may also specify a bolus dose to be given on request 
(Constant Infusion mode only).

The program will calculate the expected concentrations while the 
infusion is being administered. 


5.5  Pharmacokinetic parameter set (PK-model): 

Select the pharmacokinetic (PK) parameter set you prefer by 
pressing F5 (Change Entry).  Move the cursor between choices 
using the arrow keys:  the PK  parameters are displayed together 
with the journal reference in which the PK model was originally 
published.   After selection of your preferred PK set, the 
parameters are displayed on the left side of the screen.


5.6  Pump Type: 

Select the pump type by choosing from the pump library (F5).  If 
you intend to deliver an infusion (as opposed to perform a 
simulation), you will be prompted at this point to enter a 
communications port (COM PORT) number.  This will be the number 
of the COM port to which the RS232 interface you are using on 
your computer has been set (usually 1 or 2).  The program will 
then test whether communications are intact.  If the number you 
specify is incorrect, a message will inform you of a fault in 
communication.

If you are using both channels of the Baxter 6301 or the Imed 
Gemini volumetric pumps, set the COM port to be used by BOTH 
channels to the SAME port (COM #1 or COM #2). 


5.7  Target concentration: 

Enter the targeted concentration, taking note of the units 
employed.  These units are fixed for each drug and cannot be 
changed by the user.  (The targeted concentration is of course, 
not displayed if you have selected the bolus-and-constant-
infusion regimen). 


5.8  Maximum Plasma Concentration: 

The algorithm to target an effect-site concentration is designed 
to achieve the required concentration as rapidly as possible.  
This leads to initial plasma concentrations that are temporarily 
higher than the targeted effect-site concentrations and may 
therefore lead to unwanted side-effects.  You must therefore 
specify a maximum plasma concentration that you are prepared to 
accept and the program will not allow the calculated plasma 
concentrations to exceed that amount during drug administration. 

     PLEASE NOTE: 
     This facility to prevent excessive plasma concentrations is 
     not available in Constant-infusion mode.   If you administer 
     a large bolus and/or a rapid-enough infusion, the program 
     will not stop the pump if the calulated plasma concentration 
     exceeds the "Maximum" you specified.

During the infusion, Stelpump displays a horizontal blue line   
at the maximum specified concentration on a graph of 
concentration vs time, enabling you to confirm the maximum 
allowable concentration that you have set (see Section 6.2).  
This maximum allowable concentration may be changed during 
infusion (see Section 6.3.2).


5.9   Syringe Type: (for syringe-pumps) 

Select the brand-name from the menu (F5).  Make sure that it 
coincides with the type for which the pump is programmed.   Many 
pumps do not inform the computer  which syringe type is present, 
nor do they have a method of detecting it. 


5.10  Syringe Size: (for syringe-pumps)

Select the size (F5)
5.11  Syringe Concentration: 

Enter the drug concentration in the syringe.  A default 
concentration is suggested for each drug.


5.12  Volume present: 

Enter the volume present in the syringe.  This information will 
be used by the program to calculate the amount of drug remaining 
in the syringe during drug administration.  It will warn you that 
the syringe is nearly empty when less than 10% of the original 
volume is present and will stop the pump if the calculated 
remaining volume is zero.

 
5.13  Saving a profile file:

YOU MAY SAVE A PROFILE FILE AT THIS STAGE.

At this stage you may return to the previous screen (Screen-1, 
opening screen) by pressing F4 and you may save all the drug and 
pump information to a "Profile" file as described in section 
4.2.2.   When you next use the program, you may "load" the .PRO 
file you have saved and all the information will automatically 
appear when you reach Screen-2.  This will prove a great time- 
and labour-saving device, especially when you routinely  control 
two pumps. 

 
5.14 Confirm your entries and move to Screen-3: 

When you have entered all the required information, press F9 
(Confirm).  If any patient or drug information is missing,you 
will be advised.  If you have requested a simulation you will be 
required to confirm it by pressing F9 again.  This is to prevent 
a user from running a simulation while under the impression that 
an infusion is being administered!  If you have requested an 
infusion, the program will ask you which communication port is 
being used and then check to see if communication between 
computer and pump is intact.  You will be warned if there is a 
fault and suggestions will be made how to correct it.   




6.  ADMINISTERING THE INFUSION: (SCREEN-3) 

6.1  Function Key Menu:

As before, the help window is at the bottom of the screen.  Note 
that a certain consistency is maintained in the use of the 
function keys. 

F5:Change something.  On selecting F5 you will be presented 
     with various submenus (see later). 

F4: Return to the previous screen. 


6.2  Information displayed during the infusion(s): 

In this screen (Screen-3), information is presented graphically 
and alpha-numerically.  
Alpha-numeric information:
     
     Pump rate (volume per unit time)
     
     Infusion rate (drug mass per unit time)
     
     Calculated plasma and effect-site concentrations (in units 
     appropriate to that drug). 
     
     The infusion regimen: Constant Infusion mode or targeted 
     mode (in the latter case, the targeted concentration in the 
     plasma or effect-site).
     
     Time elapsed since starting.
     
     The concentration at which the patient is expected to 
     recover ("Wake-up" concentration).
     
     The expected time to reach the recovery concentration should 
     drug administration be stopped.  
 
Graphical information:
     
     Upper graph:  Pump rate (ml/h).
     
     Lower graph:  Plasma concentrations (in yellow).
                   Effect-site concentrations (in red).

Other information: 
     * The name of the .LOG file.  If no .LOG file has been 
       specified in the opening screen, a warning appears that no 
       information will be logged to disk.  If at this stage you 
       wish to specify a .LOG file, you may return to Screen-1 by 
       pressing F4 twice.  None of the information you have 
       entered will be lost, so that there  will be no need to 
       re-enter it on returning to Screens-2 and -3.  
       
       Note that you cannot leave Screen-3 once the infusion has 
       started other than by aborting the infusion.
        
     * Whether an infusion is being administered or a 
       simulation performed (accelerated or in real-time). 
       
     *  Duration of Delta-T (sec)
     
     *  Drug name.
     
     *  Pump name. 
     
     *  Date and time-of-day. 
     
     *  The X-axis represents 30 minutes of elapsed time 
       After the first 30 minutes the "time window" shifts by 15 
       minutes so that there is always a window of between 15 to 
       30 minutes to be observed.
       
6.3  ADMINISTERING INFUSIONS: 

6.3.1  Starting and stopping the infusion

        TO START THE INFUSION PRESS F2: 
    
    TO STOP THE INFUSION PRESS F2 AGAIN

If you have elected to "target" a concentration, the program will 
administer the initial "bolus", usually by running the pump at 
it's maximum speed.  The pump speed is adjusted at intervals of 
Delta-T (default 10 seconds) and at the same time the numeric and 
graphic information is updated. 

You will see a small "wheel" turning at the bottom of the screen.  
This is an indication that communication between pump and 
computer is intact and functioning properly.  (This does not 
appear in simulation mode).

Note that the Function Key menu at the bottom of the screen 
changes slightly on starting the infusion.  The dark red 
"buttons" (Stop [F2] and Change [F5]) apply to pump control while 
the light (orange) coloured buttons refer to additional 
information that you may obtain.

The name of the .LOG file and/or the warning that no logging will 
occur also disappear from the graphic window when the infusion 
starts.

TO STOP THE INFUSION PRESS F2: 

The plasma and effect-site concentrations continue to be 
calculated and plotted.  To restart, press F2 again.  Having 
stopped the pump you may abort the infusion by pressing F3.  
Confirm  termination (irreversibly) by pressing F2 again or else 
you may resume the infusion by pressing F4 followed by F2. 


6.3.2  TO CHANGE SOMETHING, PRESS F5: 

F5: (Change) introduces a new submenu in the Function Key window 
    while the infusion continues to run.  As before, dark-red 
    buttons pertain to pump control, light-red buttons to 
    information.  There are now four dark-red buttons: (F4, F2, 
    F3, and F5)
    
    F4:  Go back without making any changes
    
    F2:  Change the infusion REGIMEN: 
	This takes you to another submenu:
	
	Note:  You may freely switch between targeting the 
	plasma- and  effect-sites,  or administering a constant 
	infusion.
	    
	    F4: Go back without changing anything.
	    
	    F2: Target the plasma concentration:
		
		A small window appears and the present targeted 
		concentration is offered as the new target.  
		Enter the new target PLASMA concentration.    
	    
	    F6: Target the effect-site concentration
		
		A small window appears and the present targeted 
		concentration is offered as the new target.  
		Enter the new target EFFECT SITE concentration.
	    
	    F8: Administer a constant-rate infusion.
		
		A small window appears and the present infusion 
		rate is offered as the new target.  Enter the new 
		infusion rate to be administered.
		
		Note: While running in constant-infusion mode 
		       you may administer a "bolus" dose by 
		       pressing F3.  Enter the bolus dose to be 
		       administered in the pop-up window.  A 
		       previously requested bolus will be offered. 
		       
    
    F5 (Change) continued 
    
    F3: Change the LIMIT CONCENTRATIONS:
	
	This takes you to a different submenu:
	     
	    F4: Go back without  changing anything.
	    
	    F3: Change the Wake-up (recovery) concentration.
	    
	    F8: Change the maximum allowable plasma concentration.
    
    F5 (Change) continued 
    
    F5: Change the SYRINGE: 
	
	This stops the pump and allows you to remove the syringe.
	
	F4: Go back without changing anything.  Remember to 
	     RESTART THE INFUSION by pressing F2 (Start).
	 
	Or, remove the syringe and insert a new one.  Choose the 
	appropriate syringe from the menu in the pop-up window, 
	then the size, the drug concentration and finally the 
	volume present.  This returns you to the main menu and 
	you may restart the infusion.
	
	After changing the syringe, PRESS F2 (Start) TO 
	RESTART THE INFUSION. 
	
	IF YOU DO NOT PRESS F2 TO RESTART, THE PUMP WILL 
	REMAIN STATIONARY!  
TAKE NOTE AGAIN THAT THE LIGHT-RED (ORANGE) BUTTONS IN THE 
FUNCTION KEY MENU PROVIDE INFORMATION:

6.3.3.  F6 (Info):  A pop-up window provides additional 
		    information:
	
	*   Total volume and mass of drug infused.
	*   Volume remaining in the syringe. 
	*   Syringe concentration.
	*   Brand-name and volume of the syringe.
	*   The .LOG filename.
	*   The journal reference for the PK parameter set.
	*   Patient demographic details
    
    Press F6 again to remove the pop-up information window.

6.3.4  F7: (Scroll pump-rate unit) 

    Alternate between ml/hour and ml/min on the digital readout.

 
6.3.5  F8: Scroll infusion rate units:  Each time you press F8 
	the units on the digital readout change between: 
	
	mg/h
	mg/min
	mg/kg/h
	mg/kg/min
	
	Note that certain drugs (e.g. sufentanil, fentanyl, 
	alfentanil) are dosed in g units.


6.3.6  F9:  Adjust the Y-axes:
    The default upper limit for the Y-axis of the pump-rate graph 
    is the maximum speed the pump is capable of doing and this 
    range is often inconveniently wide. You may adjust the upper 
    limit for the Y-axes of both graphs by pressing F9.  Enter 
    the new limits in the pop-up window. 
    
    
    6.3.7  F10: Change today's date and the time of day.


 
7.   SOME PRACTICAL CONSIDERATIONS:

7.1  First-time users:
 
If you are using the program for the first time, it is 
recommended that you first perform several "dry runs".  First try 
out the program in simulation mode using different drugs with one 
and two syringe pumps.  Then run the program with the computer  
connected to one, and finally, to two  syringe pumps.  Create 
fault conditions deliberately to experience how both you and the 
program handle them.  Suggestions are: 
       - Run the program in it's three delivery modes (target 
	 plasma, target effect-site, bolus-and-constant-
	 infusion).
       
       - Switch between various delivery modes "on the fly".
       
       - Start the infusion with the pump switched off.
       
       - Switch off the pump while the program is running.
       
       - Disconnect the power supply to the pump while it 
	 is running: Will the pump and program to continue in 
	 battery power-supply mode without stopping and/or 
	 sounding an alarm?
       
       - Disconnect the serial cable while the pump is running.
       
       - Obstruct the outflow
       
       - Change a syringe 
       
       - Allow the syringe to run empty.
       
       - Specify a wrong Comm port
       
       - Put air in the line.
       
       - Attach a small gauge needle to outlet:  Does the 
	 pump generate an occlusion alarm while delivering a 
	 "bolus" at the maximum speed?
       
       - Remove the syringe without first stopping the pump 
	 via the computer keyboard (in Volumetric systems open 
	 the door).
       
       - How does your system respond when diathermy is
         activated?

Most users will be confronted with these faults at some time.  
Practice in handling them is important.  Please also take note of 
some of the idiosyncracies to be found with some of the 
individual pumps (Section 7.5).

 
7.2   An "empty" syringe in simulation mode: 
   
   When in simulation mode the program will ignore the fact that 
   the syringe becomes "empty".  Do not be surprised to see a 
   negative volume remaining when you press F6 (Info). 

7.3  Starting in bolus-and-constant-infusion mode:
   
   If you intend to  start your infusion in constant infusion 
   mode you may first administer a "bolus" (F3).  If you do so,  
   the program will afterwards, automatically proceed to give the 
   infusion rate that you have specified.  If you wish to give 
   only a single bolus dose initially, then you must specify an 
   infusion rate of zero. 


7.4  Alarm conditions: 
   
   Some pumps communicate fault conditions that they detect to 
   the computer.  The program, on detecting an alarm condition or 
   a breakdown in communication will immediately stop the 
   infusion.  In addition a red-coloured alarm window will appear 
   informing you of the problem.   To resume the infusion after 
   correcting  the fault, press F2 (start).

7.5 Occlusions:

Occlusion of the outlet is handled differently by different 
pumps.  Some pumps (e.g. Harvard 22) will deliver a sudden bolus 
on the occlusion being cleared and tension in the system is 
released.  Other pumps (e.g. Graseby 3400 and IVAC P4000) have 
mechanisms whereby the tension that has built up in the system 
during the occlusion must first be relieved before the infusion 
may be continued.  This may be regarded as an advantage or 
disadvantage: an advantage because it prevents the patient from 
receiving a sudden bolus of powerful drug with side effects: a 
disadvantage because Stelpump will have assumed that drug was 
delivered while occlusion pressures were building up.  On 
restarting the infusion, the program will then assume that 
greater concentrations exist. 

7.6  Runaway infusions

After several years of using Stelpump with various pumps we have 
not experienced a runaway infusion.  The possibility, however 
remote, should always be considered.  It is probably most likely 
when using a pump that does not care if communication with the 
computer is lost and communication  fails while a "bolus" dose is 
being administered at the fastest possible speed.  We advise that 
you should be prepared for such an eventuality and be ready with 
a method of physically stopping a drug infusion rapidly.  If you 
are "piggy backing" your drug into an infusion line then pull out 
the needle.  If you are using a multiple lumen catheter, this is 
not so easy.  We therefore recommend that you place a stopcock or 
tap between infsion set and patient which can be immediately 
turned off on detecting a problem.  Therefore maintain particular 
vigilance during periods of rapid infusions, for examlple  during 
induction of anaesthesia or after requesting increased targeted 
concentrations. 


7.5   Notable properties of some pumps: 

7.5.1 Harvard model 22:  
   
   The Harvard model 22 pump does not communicate any alarms to 
   the computer.  If, for example, the syringe is empty, the pump 
   will happily continue to try to crush the plunger into the 
   barrel!  Likewise if there is an obstruction (e.g. if you have 
   closed off the tap on an extension iv-set) the pump will try 
   to force it open.  If you release the obstruction a bolus dose 
   will be given rapidly by the tension that has built up in the 
   mechanism!  Therefore make sure to relieve the built-up 
   tension before clearing the obstruction. 
   
   The Harvard 22 does not require the computer to confirm it's 
   presence at regular intervals, so that if communication with 
   the computer is lost, it will continue to infuse at the rate 
   specified by the last instruction.  This problem has been 
   overcome in Stelpump by specifying a volume-to-be-infused at 
   every time-step that will cover the next two time-steps at the 
   current infusion rate, so that if the PC or the link fails, 
   the Harvard pump will continue the infusion for at most, 2 x 
   Delta-T (usually 20 seconds). 
 

7.5.2 The Graseby model 3400:
   
   Graseby model 3400 has several alarm conditions.  It does not 
   however communicate to the computer WHICH ALARM is occurring: 
   it merely informs that an alarm condition is present.  Look on 
   the display screen OF THE PUMP  to determine which alarm is 
   occurring.  
   
   The Graseby model 3400 detects pressure build-up in the event 
   of an outflow obstruction.  Furthermore, it  has a built-in 
   safety mechanism to prevent a bolus dose being given when the 
   obstruction is relieved.  A message appears on the pump-screen 
   to RELEASE CLAMP.  You must then release the clamp holding the 
   end of the syringe plunger by lifting it up and repositioning 
   it.  (Do not confuse it with releasing the clamp on the 
   infusion line that you closed and forgot to re-open after you 
   changed the syringe !) 
   
   It is crucial that the Graseby clamp fits properly over the 
   syringe plunger.  If the fit is not good, this may be a source 
   of an unknown alarm condition communicated to the computer. 
   
   The Graseby model 3400 gives a beep every time it receives a 
   new command, intended to confirm a manual adjustment to the 
   infusion rate.  Under remote control, it will therefore beep 
   every Delta-T seconds.  This may be irritating at first, but 
   does become reassuring that communication between pump and 
   computer is intact (in addition to the "turning wheel"). 
   
   The Graseby model 3400 as well as the Harvard model 22 pumps 
   need to be "told" at the pump front panel what type of syringe 
   it is using.  They do not communicate to the program the 
   syringe brand-name or internal diameter.  Using STELPUMP, it 
   is therefore possible to insert the wrong syringe and both 
   pump and program will be unaware that a different syringe type 
   is present.  
   
    On some pumps the connector to the computer serial 
   communications port and to the pump are identical (e.g. the 
   Graseby model 3400 pump if the computer has a 9-pin serial 
   port).  It is therefore possible to connect the cable the 
   wrong-way round and the system will not work.  The computer 
   will give a message that there is a communications fault. 



7.5.3 The Baxter volumetric pumps:
   The Baxter models 6201 (single channel) and 6301 (2-channel) 
   volumetric pumps are user-friendly and have excellent 
   communications protocols for computer-control.  They also have 
   the advantage of using standard Baxter intravenous infusion 
   sets thereby avoiding the issue of expensive dedicated sets. 
   
   During computer-control, the Baxter pumps do check whether 
   communication with the computer is intact and sound an alarm 
   and stop if there is a breakdown in communication.  There is 
   however a potential problem:
   Using the pump control panel, it is possible to switch the 
   pump out of computer-control mode while Stelpump is running.  
   The pump will NOT sound an alarm and is then quite happy to 
   continue infusing at whatever rate it had been running at.  
   Stelpump will usually detect the problem and sound an alarm, 
   but the pump is capable of delivering 2000 ml/hour and there 
   may be problem if someone inadvertently bumps the pump front 
   panel while the system is delivering a bolus.  This problem is 
   easily prevented by depressing the PANEL LOCK button at the 
   back of the pump.  This disables the front panel and displays 
   "LOC" on the pump's front panel, next to the infusion rate 
   display.  Therefore Always set the PANEL LOCK before starting 
   an infusion using Stelpump. 
   
   On setting up your system initially, having reached Screen-3, 
   which means that you are ready to start the infusion: If there 
   is a delay in starting the infusion, the Baxter will go out of 
   computer-control mode and you will have to reset it from the 
   front panel before being able to start your infusion.   So 
   before starting your infusion, make sure that the computer-
   control light is on.
   
   An irritating feature of the Baxter pumps is that when it is 
   inactive, the pump bleeps repeatedly after a few minutes.  
   This may happen for instance when you are targeting a drug's 
   plasma, or effect-site and have requested a lesser 
   concentration whereupon the program stops the pump and waits 
   for the calculated concentration to decrease to the target.  
   The bleep may be silenced for several minutes by pressing the 
   SILENCE button, but it will revert to the bleep again.
   
   The Baxter pumps may sound an "occlusion" alarm during 
   delivery of a rapid infusion and stop.  This is prevented by 
   setting the occlusion-alarm pressure to the highest possible 
   (17 p.s.i.) from the front panel.  To change the Baxter's 
   configuration from the front panel, switch on the pump while  
   simultaneously pressing and holding STOP and PANEL LOCK (at 
   the back of the pump).  Use the NEXT button on the front panel 
   to cycle through the various options.  To make a selection, 
   press the number of the desired selection and press PRI START.
   
   
   
   7.5.4 The Imed Gemini PC-2:
   
   The Imed Gemini PC-2 has a confusing user interface and it is 
   advisable first to gain familiarity with the pump in stand-
   alone mode before attempting computer control.  It also 
   suffers from the disadvantage that it relies on dedicated 
   infusion sets which are somewhat expensive.  An advantage of 
   the Imed Gemini PC-2 is that sets are availble that enable  
   drug delivery from syringes in place of a bag or bottle 
   (Baxter Vented Syringe Set, part No. 2280).  The pump is very 
   sensitive to small amounts of air in the infusion line, so be 
   meticulous in setting up the infusions(s).  The connector to 
   the syringe cracks easily, resulting in air aspiration.  When 
   using a bag reservoir, it is important to ensure that the air 
   vent is blocked off to prevent asipiration of large amounts of 
   air.  
   
   The pump must be set up with the correct configuration using 
   the pump's front panel.  To go into the Setup procedure:
   
   1. Press the unmarked button on the right side while pressing 
   POWER ON.  Keep the unmarked button depressed until "SETUP" 
   scrolls across the display.
   
   2. Press the unmarked button to scroll through the setup 
   options.
   
   3. Change an option by pressing START and then the up or down 
   arrows
   
   4. To exit Setup:  When "EXIT SETUP" scrolls across the 
   display, press START.
   
   The following modes must be set for computer control:
   
   - Normal
   - Computer control
   - Primary infusion
   - Standard infusion
   - Ready
   - Macro
   
   Please take note of the following:
       
       * The pump must be in the "P" (pump delivery) mode and not 
	 in the "C" (continuous or gravity-feed) mode.  There is 
	 a green light on the front panel marked "Pump" that 
	 illuminates when in "P" mode.  If you attempt to run the 
	 program with the pump set in the "C" mode, the pump will 
	 give an alarm as soon as it senses any pressure that is 
	 greater than that generated by the column of fluid 
	 leading up to the reservoir bag/bottle.
       
       * The serial number of the pump can be set from the front 
	 panel.  The serial number must be set to a non-zero 
	 number.  If the serial number is set to zero, 
	 communication between computer and pump will 
	 malfunction!
       
       * Set the occlusion-pressure alarm to the highest possible 
	 value to avoid an occlusion-alarm during bolus delivery.
   
   Establishing communication between the computer and the Imed 
   Gemini PC-2 is somewhat finicky.  Observe the following 
   sequence.  
    
   1. Switch on the pump with the pump cable connected to the 
       computer: the green "Monitor" light will illuminate, 
       indicating that it has detected the presence of the 
       computer.  If the "Monitor" light does not illuminate, it 
       will do so when you start running Stelpump: From Stelpump 
       Screen-1 you select INFUSE (1, or alternatively, 2 
       pump(s)).  
   
   2. Press the "Monitor" button on the pump control panel and 
       the display will change to "Computer control".  
   
   
   The Imed Gemini PC-2 has proved to be a difficult animal to 
   tame, and the resident software has some inconsistencies.  For 
   example, if you disconnect the cable while the pump is in 
   computer-control mode, the pump will detect the loss of 
   communication immediately, sound an alarm and report an error 
   "COMMS CABLE KVO".  If Stelpump is terminated ("aborted") 
   while the pumps are stopped the Imed will not detect the fact 
   that it has lost communication with the computer.  If you then 
   switch off the computer, only then will the pump will report 
   "COMMS CABLE KVO".  Furthermore, if you switch the pump out of 
   "Computer-control" mode into "Monitor" mode at the pump's 
   control panel, the pump does not care that it has lost 
   communication with the computer and continues to infuse at 
   whatever rate it was going when communication was lost.  This 
   problem has been overcome by specifying a volume-to-be-infused 
   (VTBI) with each instruction.  If communication fails, then 
   the VTBI is completed, the pump stops, bleeps and announces 
   that the VTBI has indeed been completed. (Notice that during 
   computer-control the VTBI changes occasionally on the pump 
   display panel: this is normal).
   
   Like the the Baxter, the IMED Gemini PC-2 has a button at the 
   back of the pump, which if you depress and hold it, disables 
   the keyboard.  This button was designed for use during stand-
   alone mode to prevent tampering.  Unfortunately it cannot be 
   used during computer-control: Once the keyboard is disabled 
   you cannot switch into computer-control mode, but if the pump 
   is already in computer-control mode, you cannot disable the 
   keyboard.  So there is always the danger (unlike the Baxter 
   pumps) that someone can accidentally switch the pump over to 
   "Monitor" mode while Stelpump is controlling the pump.
   
   
   The Imed Gemini PC-2 pump seems to have a very slow 
   microprocessor and, in addition it is extremely verbose, 
   sending long strings of data.  As a result, communication time 
   becomes significant and this may lead to timing errors.  If 
   the computer polls the pump for it's status it can take up to 
   two seconds to receive all the data!  Stelpump therefore 
   relies on the VTBI principle to stop the pump should there be 
   a breakdown in communication.
   
   
   If the Imed is used in conjunction with a Graseby 3400, the 
   latter may "timeout" and give an alarm, indicating that 
   communication has been lost with the computer because the 
   Graseby may require confirmation of the computer's presence 
   while the latter is still "listening" to the Imed pump. 
   Therefore avoid using the Imed and the Graseby pumps together. 
   The Imed Gemini PC-2 does not have a an Empty Container 
   Detector so that the program relies on it's own calculations 
   to determine when the bag(s) is (are) nearly empty or empty. 
   
   
   On starting an infusion at the maximum infusion rate (e.g. at 
   the beginning of a targeted infusion) the Imed Gemini PC-2 
   will occasionally come up with an occlusion alarm as it tries 
   to overcome the initial inertia of the system.  Retrying 
   generally solves the problem.  Remember to set the occlusion 
   alarm pressure to the highest possible value. 
         
   
   Like the Baxter, the Imed gives an alarm if inactive, and this 
   feature cannot be disabled.
   
   
 
7.5.5 The Braun Perfusor Secura:

The Braun Perfusor Secura referred to here, is the "old" model 
which is no longer in production.  It has been included in this 
library because there are several of them still in use in the 
Tygerberg Hospital in Cape Town.  It can however, pose problems.  
Unlike most other pumps that are based on the master-slave 
philosophy and which  expect the computer to initiate ALL 
communications, it sends unsolicited information.  Most 
importantly, it does not require confirmation of the presence of 
the computer so that if communication breaks down, it will 
continue to infuse ad infinitum at the rate specified by the last 
request it received.  This problem cannot be solved by giving the 
pump a volume-to-be-infused (as with the Harvard 22).  

The maximum infusion rate of the Braun Perfusor Secura is only 
99.9 ml/h, using a 50 ml syringe, which is too slow an initial 
infusion for many of the drugs used in anaesthesia (e.g. 
propofol).  Maximum infusion rate can be doubled to 199.8 ml/h by 
using two 50 ml syringes in parallel, but that may also be too 
slow for some drugs.  Remember to indicate to Stelpump whether 
you are using one or two syringes because if you use two 
syringes, the infusion rate actually delivered by the pump is 
doubled and the program has to take that into consideration by 
halving the requested pump rate.  Also, please note that the 
Perfusor Secura uses only dedicated BRAUN SYRINGES.  

When the Braun Perfusor Secura gives an alarm condition, the only 
method to clear it is by switching it off and on again.  This may 
then give rise to spurious communication-failure alarms by 
Stelpump.  This is not serious, but you need to know what to 
expect. 

Unlike the Graseby 3400 the Braun Perfusor Secura does not 
indicate the volume present in the syringe, so that the volumes 
infused and remaining are calculated and may be inaccurate.



7.5.6 The IVAC P4000:

Earlier versions of the IVAC P4000 syringe pump did not allow 
infusion rates to be changed "on the fly", requiring that the 
computer first issue an intruction for the pump to stop, then 
issue the instruction for the new rate and then restart the pump.  
It is now possible to change the infusion rate on the fly but at 
a price of increased complexity.  Before using the IVAC P4000 for 
computer-control, the following user-defined options MUST be set:

Hold in START  while switching the pump on (see P21 of the IVAC 
manual).  

Access Code		Description 				Setting

359				Default syringe size		d50 (50 ml)
906				Extended range				n-1 (enabled)
269				Rate change during infusion	r-1 (enabled)

You will notice that the maximum speed delivered by the IVAC 
P4000 when administering a bolus is 999 ml/h.  The faster "bolus" 
infusion rate that can be administered using the pump's front 
panel is not accessible by computer-control.


7.6 Sources of inaccuracy: 

When using STELPUMP for research purposes, one should be aware of 
potential sources of inaccuracy.  These inaccuracies are 
difficult to quantify, but can be minimised through careful 
application of the system.

Firstly, STELPUMP uses Euler's numerical integration technique 
[1] to calculate concentrations and infusion rates.  This method 
produces approximate solutions because Delta-T is not infinitely 
small.  Ideally one could approach the correct solutions more 
accurately by reducing Delta-T, but the reaction times of 
infusion pumps, communication delays and any jitter in the system 
then become more significant and consequently introduce other 
errors.  A DeltaT of 10 seconds is considered optimal.

Sources of system jitter can include computer processing time and 
the fact that the software is not real-time pre-emptive.  The 
effect of the former can be minimised by only running STELPUMP on 
a 486 or faster PC.  The latter effect implies that the system 
cannot be guaranteed to react to or cause real-time events 
exactly on time.  The effect will be more pronounced when 
STELPUMP is controlling two pumps simultaneously.  In practice 
such errors are small, but they are present and variable.  Again, 
the faster the PC, the smaller the problem.

Infusion pumps have a certain inertia and do not deliver the 
requested infusion rate instantaneously.  The delay is often more 
pronounced when a pump is started for the first time because some 
pumps appear to perform various start-up checks.  STELPUMP does 
not compensate for these delays.

Additionally, some pumps, such as the older model Ivac P4000, 
stop and restart every time a new infusion rate is commanded.  
The accumulative effect of an infusion lasting several hours 
could well be significant if one considers that the stop-start 
sequence happens every DeltaT (usually 10) seconds.

Finally, another source of inaccuracy can be the limitations of 
the pumps themselves.  Most syringe pumps are inaccurate at rates 
below 5 ml per hour.  A pump may well deliver 1 ml during one 
hour but WHEN that occurs during that hour may be unknown.  At 
low rates, problems with syringes become significant: for example 
the phenomenon of "stiction" where the plunger movement is not 
smooth due to friction between plunger and barrel leading to 
jerky movement of the plunger.  Air bubbles within the syringe 
may cause inaccuracies because of their compressiblity.  It is 
advisable to dilute drugs so that the slowest expected infusion 
rate should not be less than 10 ml per hour.  



8.  .LOG FILES:

The computer will "log" all activities to a comma-delimited file 
with the extension .LOG.  This may be read into a spreadsheet for 
further analysis.  If you are doing several cases in succession, 
all the cases will be appended to the same file unless you 
specify a different .LOG file for each case. 

An example of a .LOG file resulting from simulated, effect-site-
targeted, two-pump infusions of propofol and sufentanil is found 
in EXAMPLE1.LOG.   The resulting spreadsheet is in EXAMPLE1.WK1.  
If you load the latter into your spreadsheet program you should 
note the following:

The first seven rows contain the following information:
Date:
Time:
The type of infusion (e.g. Accelerated Simulation)
Simulation Period (i.e. Delta T)
Patient demographic data: age, mass, sex.

Row 8 identifies whether Pump #1 or #2 is being documented 
(Column B for pump #1 and column G for pump #2).

Rows 9 to 18: (Column B for pump #1 and column G for pump #2).
Pump name:
Drug name:
PK model name:
Literature reference for model name:
Site targeted or constant infusion:
Targeted concentration: 
Syringe brand name:   Syringe size:
Volume present:        
Syringe concentration: 

From row 19 onwards data is written in the following columns.

   A           B         C            D           E         F
----------------------------------------------------------------
TIME OF     ELAPSED    PLASMA       EFFECT-S     PUMP     VOLUME 
 DAY         TIME      CONCENTR     CONCENTR     RATE     GIVEN 
             (min)                              (ml/h)     (ml) 
 ..           ..         ..           ..          ..        .. 
 ..           ..         ..           ..          ..        .. 

Likewise for pump #2 in columns G to K.

You will see that the columns of data are interupted occasionally 
to document alarm conditions, adjustments to targeted 
concentrations, change of syringe, etc. and the time of day that 
they occurred.   If you wish to utilize (e.g. graph) your 
numerical data, you will first have to erase the interrupting 
text and make the data columns continuous.  This is easily done 
using the spreadsheet's "Move" command. 
9.  CABLE CONNECTIONS FOR  VARIOUS PUMPS:

9.1  Graseby 3400
   
   Graseby 3400 pump          Computer             Computer
   DB9S (female)              DB9S (female)        DB25 (female)
   
   CTS 8  ------------------- 7 RTS ----------------- 4 RTS
   DSR 6  ------------------- 4 DTR ----------------- 20 DTR 
   RD  2  ------------------- 3 TD  ----------------- 2 TD 
   TD  3  ------------------- 2 RD  ----------------- 3 RD 
   GND 5  ------------------- 5 GND ----------------- 7 Sig GND 
                                        Cable screen  1
   
   NOTE:  Because the cable connectors are identical at both 
   ends, it is possible to connect the cable the wrong-way-round 
   and the system will not function.  So label appropriately.
   
   The connections are essentially the same as the Imed Gemini 
   PC-2 except that the Imed Gemini cable has  a DB9 plug (male) 
   at the pump end.





9.2  Harvard Model 22

   Harvard 22 pump            Computer             Computer 
DB9S (female)              DB9S (female)        DB25S (female)

GND 7 -+
       |
GND 1 -+--------------------- 5 GND ----------------- 7 Sig GND 
RXD 2 ----------------------- 3 TD  ----------------- 2 TD 
TXD 3 ----------------------  2 RD  ----------------- 3 RD 
                                        Cable screen  1 

NOTE:  Because the cable connectors are identical at both ends, 
it is possible to connect the cable the wrong-way-round and the 
system will not function.  So label appropriately.
9.3 Imed Gemini PC-2: 

Imed Gemini PC-2 pump      Computer             Computer
DB9P (male)                DB9S (female)        DB25S (female)

CTS 8  ------------------- 7 RTS ----------------- 4 RTS
DSR 6  ------------------- 4 DTR ----------------- 20 DTR 
RD  2  ------------------- 3 TD  ----------------- 2 TD 
TD  3  ------------------- 2 RD  ----------------- 3 RD 
GND 5  ------------------- 5 GND ----------------- 7 Sig GND 
                                     Cable screen  1

The connections are essentially the same as the Graseby 3400 
except that the Imed Gemini cable has  a DB9 plug (male) at the 
pump end so that it is not possible to connect it the wrong way. 



9.4 Braun Perfusor Secura

This wiring diagram refers to the "old style" pump that is no 
longer in production.  It has the ablility to mount two syringes 
in parallel, thereby doubling it's maximum infusion rate to 200 
ml/h. 

Perfusor Secura pump       Computer             Computer
DB25P (male)               DB9S (female)        DB25S (female)

DSR 6  ------------------- 4 DTR ----------------- 20 DTR 
RD  3  ------------------- 3 TD  ----------------- 2 TD 
TD  2  ------------------- 2 RD  ----------------- 3 RD 
GND 7  ------------------- 5 GND ----------------- 7 Sig GND 

 
9.5 IVAC P4000

Pump                       PC         PC
DB9 S (socket)            DB9S       DB25S
RXD 2----------------------3 TXD----2 TXD
TXD 3----------------------2 RXD----3 RXD
GND 5----------------------5 GND----7 GND
EN 8-----------------------7 RTS----4 RTS
9.6 BAXTER 6201 and 6301

Pump                       PC          PC
DB9 P (male)              DB9S       DB25S
RXD 2----------------------3 TXD----2 TXD
TXD 3----------------------2 RXD----3 RXD
CTS 7 ---+                       +--4 RTS
         |                       |
RTS 8 ---+                       +--5 CTS

                                 +--6 DSR
                                 |
                                 +--20 DTR
                        +--6 DSR
                        |
                        +--4 DTR

                        +--7 RTS
                        |
                        +--8 CTS
GND 5----------------------5 GND----7 GND
     shield-------------------------Chassis
EN 8-----------------------7 RTS----4 RTS


 




10.  REFERENCES:

1. Shafer SL, Siegel LC, Cooke JE, Scott JC:  Testing computer-
   controlled pumps by simulation. Anesthesiology 68:261-266, 
   1988

2.  Jacobs JR, Williams EA.  Algorithm to control effect 
   compartment drug concentrations in pharmacokinetic model-
   driven drug delivery.  IEEE Trans Biomed Eng 1993, 40:993-999 
   
11. Registration

Please register with us by filling out the form below and send it 
either by E-Mail to: JFC@maties.sun.ac.za

Or mail it to:

Dr J.F. Coetzee 
Department of Anesthesiology
Faculty of Medicine, University of Stellenbosch
P.O. Box 19063
7505 Tygerberg
South Africa


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