U.S. patent application number 12/618348 was filed with the patent office on 2010-03-04 for method and apparatus for controlling the compounding of a pharmaceutical admixture.
This patent application is currently assigned to BAXTER INTERNATIONAL INC.. Invention is credited to Ronald W. Czarny, Joseph J. Kircher, Robert E. Lewis, Joe A. Miller, Diane M. Nitzki-George.
Application Number | 20100057264 12/618348 |
Document ID | / |
Family ID | 26864368 |
Filed Date | 2010-03-04 |
United States Patent
Application |
20100057264 |
Kind Code |
A1 |
Kircher; Joseph J. ; et
al. |
March 4, 2010 |
METHOD AND APPARATUS FOR CONTROLLING THE COMPOUNDING OF A
PHARMACEUTICAL ADMIXTURE
Abstract
A method of controlling the compounding of a prescribed
admixture, the method performed by a computer under control of a
computer program, the method including: inputting the prescribed
admixture; determining if a concentration of the prescribed
admixture is within an allowed range; and if the concentration is
within the allowed range, choosing which of at least two of the
following compounding setups to employ (i) a high and a low flow
compounding setup for the prescribed admixture, (ii) a low flow
compounding setup for the prescribed admixture, and (iii) a high
flow compounding setup for the prescribed admixture.
Inventors: |
Kircher; Joseph J.; (Gurnee,
IL) ; Czarny; Ronald W.; (Cary, IL) ; Lewis;
Robert E.; (Lindenhurst, IL) ; Nitzki-George; Diane
M.; (Deerfield, IL) ; Miller; Joe A.; (Lake
Zurich, IL) |
Correspondence
Address: |
K&L Gates LLP
P.O. Box 1135
Chicago
IL
60690-1135
US
|
Assignee: |
BAXTER INTERNATIONAL INC.
Deerfield
IL
|
Family ID: |
26864368 |
Appl. No.: |
12/618348 |
Filed: |
November 13, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11131088 |
May 16, 2005 |
7620479 |
|
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12618348 |
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|
09729498 |
Dec 4, 2000 |
6975924 |
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11131088 |
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60168695 |
Dec 3, 1999 |
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Current U.S.
Class: |
700/285 |
Current CPC
Class: |
B01F 13/1069 20130101;
H01L 2924/0002 20130101; B01F 2215/0034 20130101; H01L 23/485
20130101; H01L 27/0823 20130101; B01F 13/1066 20130101; H01L
21/8222 20130101; G16H 20/10 20180101; G16H 70/40 20180101; G16H
40/63 20180101; Y10T 436/2575 20150115; Y10T 436/25 20150115; B01F
13/1063 20130101; H01L 2924/0002 20130101; H01L 2924/00
20130101 |
Class at
Publication: |
700/285 |
International
Class: |
G05D 11/02 20060101
G05D011/02 |
Claims
1. A method of controlling the compounding of a prescribed
admixture, the method performed by a computer under control of a
computer program, the method comprising: inputting the prescribed
admixture; determining if a concentration of the prescribed
admixture is within an allowed range; and if the concentration is
within the allowed range, choosing which of at least two of the
following compounding setups to employ (i) a high and a low flow
compounding setup for the prescribed admixture, (ii) a low flow
compounding setup for the prescribed admixture, and (iii) a high
flow compounding setup for the prescribed admixture.
2. The method of controlling the compounding of a prescribed
admixture of claim 1, further comprising inputting at least one of
(a) patient identification information and (b) patient specific
data.
3. The method of controlling the compounding of a prescribed
admixture of claim 1, further comprising determining a range of
acceptable concentration levels for a plurality of ingredients of
the prescribed admixture.
4. The method of controlling the compounding of a prescribed
admixture of claim 1, further comprising (a) overriding an alert or
(b) rejecting the prescribed admixture if the concentration is
outside the allowed range.
5. The method of controlling the compounding of a prescribed
admixture of claim 1, which includes determining a number of at
least one of (a) compatibility groups and (b) rinses if at least
one of setup (i) and setup (iii) is chosen.
6. The method of controlling the compounding of a prescribed
admixture of claim 1, which includes determining if lipids are
present in the prescribed admixtures.
7. The method of controlling the compounding of a prescribed
admixture of claim 6, wherein determining if lipids are present
includes determining if lipids are included in a final bag.
8. The method of controlling the compounding of a prescribed
admixture of claim 7, wherein if lipids are included in the final
bag, determining if the lipids are required to be first in the
final bag.
9. The method of controlling the compounding of a prescribed
admixture of claim 6, wherein if lipids are present, determining if
lipid haze is a concern.
10. The method of controlling the compounding of a prescribed
admixture of claim 9, wherein if lipid haze is a concern, not
preparing the prescribed admixture.
11. The method of controlling the compounding of a prescribed
admixture of claim 1, which includes applying a rule of mixing a
total parenteral nutrition ("TPN") solution.
12. The method of controlling the compounding of a prescribed
admixture of claim 11, wherein the rule is selected from the group
consisting of (i) phosphate salts are added before calcium salts;
(ii) a determination of calcium phosphate solubility is made based
on a volume of solution in the TPN bag at the time calcium is
added; (iii) unless lipids are required as a last additive, calcium
is to be the last additive to the TPN bag; and (iv) compatibility
groups are numbered sequentially to coincide with an order of
mixing unless specific exceptions are identified.
13. The method of controlling the compounding of a prescribed
admixture of claim 6, which includes calculating solubilities with
or without a volume of the lipids.
14. The method of controlling the compounding of a prescribed
admixture of claim 1, which includes determining if a total volume
of the prescribed admixture, excluding lipids, is more than a
funnel volume.
15. The method of controlling the compounding of a prescribed
admixture of claim 14, wherein if the total volume is more than the
funnel volume, transferring instructions to a compounder if a
source rinse of a base of the prescribed admixture can be held for
a rinse in an acceptable sequence.
16. A method of controlling the compounding of a prescribed
admixture, the method performed by a computer under the control of
a computer program, the method comprising: inputting the prescribed
admixture; determining if a concentration of the prescribed
admixture is within an allowed range; if the concentration is
within the allowed range, determining if lipids are present in the
prescribed admixture; and if lipids are present, determining if the
lipids are required to be contained in a final bag.
17. The method of controlling the compounding of a prescribed
admixture of claim 16, wherein if lipids are required to be
contained in a final bag, and lipid haze is a concern, not
preparing the prescribed admixture.
18. A method of controlling the compounding of a prescribed
admixture, the method performed by a computer under the control of
a computer program, the method comprising: inputting the prescribed
admixture; choosing which of at least two of the following
compounding setups to employ (i) a high and a low flow compounding
setup for the prescribed admixture, (ii) a low flow compounding
setup for the prescribed admixture, and (iii) a high flow
compounding setup for the prescribed admixture determining if a
concentration of the prescribed admixture is within an allowed
range; and altering the control of the compounding under the chosen
setup based upon whether lipids are present in the prescribed
admixture.
19. The method of controlling the compounding of a prescribed
admixture of claim 18, which includes determining if a
concentration of the prescribed admixture is within an allowed
range and performing the choosing step if the concentration is
within the allowed range.
20. The method of controlling the compounding of a prescribed
admixture of claim 18, altering the control of the compounding
under the chosen setup based upon whether lipids are present in the
prescribed admixture includes determining if the lipids are
included in a final bag.
Description
PRIORITY CLAIM
[0001] This application is a continuation of U.S. patent
application Ser. No. 11/131,088 filed May 16, 2005, entitled
"Method and Apparatus for Controlling the Strategy of Compounding
Pharmaceutical Admixtures", which is a continuation of U.S. patent
application Ser. No. 09/729,498 filed Dec. 4, 2000, entitled
"Method and Apparatus for Controlling the Strategy of Compounding
Pharmaceutical Admixtures" now U.S. Pat. No. 6,975,924, which
claims the effective filing date of U.S. Provisional Application
No. 60/168,695 filed Dec. 3, 1999, the entire contents of each of
which are hereby incorporated by reference and relied upon.
BACKGROUND
[0002] The present invention generally relates to a method and
apparatus for preparing and accounting for pharmaceutical
admixtures. More particularly, it relates to strategies for
preparing prescriptions for parenteral admixtures, for controlling
the compounding apparatus, and for properly accounting for the
prepared admixture with the strategies being implemented in
computer software.
SUMMARY
[0003] Pharmaceutical parenteral admixtures are a combination of
sterile drugs that are mixed together under aseptic conditions and
are intended for intravenous infusion. These admixtures may be
relatively simple or extremely complex, with the complexity
increasing with the inclusion of multiple active ingredients.
Nutrition admixtures are one example of complex parenteral
admixtures that are frequently prepared in a hospital pharmacy for
treating patients in the hospital. In general parenteral nutrition
admixtures ("PN") refer to most types of nutritional solutions for
intravenous feeding. Total parenteral nutrition admixtures ("TPN")
generally refer to those PNs that do not contain lipids as a
component, and total nutritional admixtures ("TNA") refer to those
PN's that contain lipids.
[0004] The pharmacy of a hospital, a compounding center or a care
facility prepares or compounds a prescription which typically has
been determined by a physician singularly or in conjunction with a
dietician, pharmacist or other care provider. The pharmacy may be
required to compound large numbers of PN on a daily basis. The
actual PN compounding is done primarily by electromechanical mixing
equipment called compounders which are extremely sophisticated and
are adapted to admix many different components in differing
proportions as set forth in pharmaceutical prescriptions.
[0005] Compounders include high volume compounders which are
adapted to prepare PN by transferring those components which are
normally found in relatively large volumes in a PN, for example
amino acids, sterile water, lipids and dextrose, at a relatively
high speed. Such compounders include the AUTOMIX 3+3 compounder
manufactured by the Clintec Nutrition Division of Baxter Healthcare
Corporation.
[0006] Compounders also include low volume compounders such as
compounders from the same corporation marketed as a MICROMIX
compounder. The MICROMIX compounder is adapted to accurately
transfer those components that are normally found in relatively
small volumes in a PN.
[0007] It is common for pharmacies to produce a prescribed PN by
utilizing both a MICROMIX and an AUTOMIX compounder, typically by
adding the high volume components to the final container or final
bag with the AUTOMIX compounder and then transferring the final bag
to the MICROMIX compounder for transferring the smaller volume
components. It should be understood that a single compounder may
have the capability of transferring both high volume components and
low volume components either sequentially or concurrently.
Alternatively, the single compounder could have both a high volume
module and a low volume module that could transfer fluid to a
common manifold, a common transfer tube connected to a final bag or
container, or into separate ports in a final bag.
[0008] To prepare such PN at an acceptable cost it is important
that the PN are compounded as efficiently as possible. Efficiency
is generally achieved by seeking to maximize the number of PN's
prepared over a given period of time or "throughput". However, the
complexity of properly preparing PN tends to slow down such
throughput. Areas of complexity may be found in determining the
proper PN for a given prescription for a particular patient,
accurately preparing the PN and accounting or billing for the PN.
However, safety of the patient is paramount and efficient PN
preparation must be accomplished with little possibility of
errors.
[0009] In preparing the proper prescription for a particular
patient the pharmacist must perform many tasks including evaluation
and determination of the proper components and their respective
amounts. Patient specific factors including the type of patient
i.e. neonatal, and weight of patient, will be considered. Improving
the ability of the pharmacist in making such evaluations and
determinations will increase the throughput and reduce the
possibility of errors. For record keeping purposes it is desirable
and on occasion required for the pharmacist to note in a permanent
record why the prescription differs from generally desired amounts
of source solutions.
[0010] As is well known in pharmacy practice, much of the
complexity involved in preparing PN results from compatibility
issues relating to the components that are placed in the prescribed
PN. Compatibility is defined as the interaction between a drug and
all other components with which that drug comes into contact,
including but not limited to the diluent, the container and other
drugs in the same PN. Compatibility is divided into two
subcategories which are physical as well as chemical compatibility.
Physical compatibility is defined as an incompatibility that will
alter the physical appearance of the drug, typically resulting in a
visual change such as precipitation, gas evolution or a change in
color. Chemical incompatibilities are not visually observed but
must be analytically tested. Chemical incompatibilities occur as a
result of changes in the active drug such as oxidation or
photodegradation. Factors that can influence compatibility include,
but are not limited to the total diluent volume, concentration
levels, the order of admixing and the pH.
[0011] There are two steps in the evaluation of compatibility and
parenteral admixtures. First, compatibility of the entire PN over
the period between preparation of the admixture and completion of
delivery to the patient should be evaluated prior to compounding.
Secondly, the compounding preparation process must be planned in a
way to allow for compatibility while the compounding process is
proceeding. For example, the compatibility between a source
solution being added to the final mixing container or any
intermediate mixing container and the solution present in that
container should be evaluated. In many instances source solutions
which are packaged at concentrations which are incompatible with
other solutions must be diluted before they come into contact with
each other in such chambers.
[0012] As can be appreciated the highest dilution will occur when
the greatest amount of diluting fluids are already present in the
container into which the solutions are being added. For example,
amino acid or dextrose source solutions will form a large portion
of a PN and yet are typically compatible with most additives. Thus
it would seem to that these solutions would be transferred first to
the final container or to any intermediate mixing chambers to
dilute added source solutions.
[0013] An additional complexity that must be considered is the
prevention of the contact between highly concentrated solutions
which are incompatible with each other along a common flowpath in
the compounder. In a representative instances, although source
solutions may flow along separate tubes for much of a transfer
flowpath, there may be a section along a transfer flowpath which is
common to the two incompatible source solutions. This common flow
path may be found along any part of the flow path such as in an
intermediate mixing chamber or after the intermediate mixing
chamber or after a switching valve.
[0014] One method to reduce the possibility of a solution being
incompatible with a second solution along a common flow path is to
flush the common flow path after each solution has been
transferred. Such flushing is accomplished with a solution which is
compatible with both the prior solution as well as the solution to
be added after the flush. As can be appreciated frequent flushing
dilute the incompatible solutions thereby making them compatible
but will also decrease throughput.
[0015] Also there must be a source of fluid for such a flushing
scheme. The source of such flushing solutions may either be a
compatible source solution which forms a part of the prescription
or the solution present in a downstream chamber such as an
admixture in the final mixing container. However, in present
pharmacy practices; the prescribed amount of solutions which are
used as flushing solutions are typically transferred first to the
final container for expediency and dilution purposes and are not
available as flushing solutions. In this instance and by default
the solution in the final bag must be compatible with the solution
which is to be flushed, and the flushing solution will be drawn
from the final container. Drawing the flush from the final bag and
returning the flush to the final bag decreases throughput. On the
other hand holding back an amount of the diluting source solutions
for flushing may lead to instances where two incompatible solutions
come into contact with each other in the final mixing chamber
without being properly diluted to a compatible concentration.
[0016] In an effort to increase efficiency, a pharmacist will
typically group solution containers in dependence on the operating
scheme of the compounder so that ingredients which are compatible
with each other (at source solution concentration) are added
together sequentially between rinses which are set by the
pharmacist. After making a determination regarding the
compatibility of the various solutions the pharmacist may group a
set of compatible solutions on station 1-4, a second set of
compatible of compatible solutions on stations 5-8, etc with rinses
set after station 4, station 8, etc. However, a particular
admixture may require 5 solutions which are compatible. Because
setting rinses requires greater time and effort, the pharmacist may
hang the fifth ingredient at a station which has rinses before and
after rather than adjust the station arrangement and rinsing
scheme. This however is not optimal.
[0017] Another consideration for a pharmacist when compounding
multiple prescriptions comprising a mixture of TNA and TPN is lipid
hazing in which a trace of lipid is present in a final solution
which is not to contain lipids. Hazing can be produced by lipids
being present in amounts as low as one to 3 parts per million. Such
hazing will typically occur when a prescription containing lipids
is compounded immediately prior to a prescription which is not to
contain lipids. Lipid hazing is not generally believed to create a
health hazard, however lipid hazing in a PN which is to be infused
may be later mistaken for a PN with unacceptable precipitation
arising from an error in formulating a compatible PN solution, and
the hazy solution may be mistakenly discarded.
[0018] If lipid hazing is an issue the pharmacist may seek to avoid
such problems by flushing the compounder after each prescription
containing lipids is compounded. However, such flushing will
decrease throughput and not be totally effective. To increase
throughput, the pharmacist may decrease such flushing by grouping
lipid prescriptions; however such groupings have a negative impact
on flexibility. If lipid hazing is not an issue, the possibility of
lipid hazing should be communicated to persons who are compounding
the solution and who are administrating the PN to the patient to
prevent the administer from mistakenly believing that the admixture
has become unstable.
[0019] Other methods of seeking to prevent lipid hazing are to use
a completely separate flowpath for the lipids to the final mixing
container. However, once lipids are present in a final container
flushing or rinsing using solution from the final container will
introduce lipids into the flowpath and may cause lipid hazing in a
subsequent PN.
[0020] Adding to the complexity of compounding the pharmacist must
consider is the accuracy limits of the compounders such that
prescriptions which have ingredients in volume levels below the
accuracy limit of the compounder will likely be added by hand
utilizing a syringe. Such manual addition decreases throughput.
Also inefficiencies inherent in the administration of the PN to the
patient such as residual volumes in administration sets must also
be considered. Accounting for the complexities has proven to be
time consuming and lead to inefficient activities and
practices.
[0021] For reimbursement and record keeping purposes, the prepared
admixture must be accounted for which is generally accomplished by
reporting either manually or electronically transferring
information into a facility's accounting system. The steps the
pharmacist must perform to insure that an admixture is properly
accounted for should be minimized to increase efficiency.
[0022] Thus, it is a primary object of the present invention to
provide an improved method and apparatus for preparing and
accounting for parenteral nutrition solutions. It is a further
object of the present invention to provide a method and apparatus
for preparing a parenteral admixture to reduce instances of
incompatibility, which preferably includes a software
implementation of the method that will accommodate many known
active ingredients and other components that are set forth in
various prescription admixtures. More particularly, it is a related
object to provide strategies for preparing prescriptions for
parenteral admixtures, for controlling the compounding apparatus,
and for properly accounting for the prepared admixture with the
strategies being implemented in computer software.
[0023] It is another primary object of the present invention to
provide such an improved method and apparatus for preparing a
parenteral admixture by increasing the throughput of a compounder,
principally by minimizing the number of rinses that have to be
performed.
[0024] A related object of the present invention lies in the
provision for selectively determining the order or reorder of a
plurality of admixture solutions or compatibility groups that may
reside in a prescription, to more efficiently prepare the
prescriptions, such as by maximizing the number of prescriptions
which may be prepared over a set time period.
[0025] A more detailed object of the present invention is to
provide such an improved method and apparatus for controlling a
compounder of the type which utilizes an intermediate mixing
chamber such as a funnel for admixing components prior to
transferring the contents of the chamber to the final mixing
chamber such as a final bag.
[0026] Another object of the present invention lies in the
provision of patient specific data to enhance the ability of the
pharmacist to efficiently formulate and safely compound admixtures
from prescriptions.
[0027] Still another object of the present invention is to provide
an improved method and apparatus for allowing the pharmacist to
efficiently compensate for the accuracy limits of the compounder
and inefficiencies in administering the PN to the patient such as
the fluid which is lost in the administration sets.
[0028] Yet another object of the present invention is to provide an
improved method and apparatus which includes a higher concentration
formulation of an ingredient to be substituted for a prescribed
formulation but determines whether the diluting fluid may be
provided by compatible other ingredients so that the volume of the
resultant admixture is minimized.
[0029] Another object of the present invention is to provide such
an improved method and apparatus which controls the compounding to
alert users when recommended limits are not being adhered to and
such alerts are not accidentally ignored. A related object is to
provide for the input and recording of the rationale in overriding
a warning.
[0030] Another object of the present invention is to provide a
method and apparatus which reduces instances or alerts users to the
possibility of lipid hazing and the possibility that such lipid
hazing will be accidentally mistaken for an unacceptable
precipitate.
[0031] Additional features and advantages are described herein, and
will be apparent from the following Detailed Description and the
figures.
BRIEF DESCRIPTION OF THE FIGURES
[0032] FIG. 1 is a block diagram illustrating the apparatus of the
present invention shown in the context of a hospital having a
central billing and patient computer which is networked to the
apparatus of the present invention and with the apparatus also
operatively connected to compounders and printers;
[0033] FIG. 2 is a perspective view of a representative compounder
that may be controlled by the method and apparatus of the present
invention, and particularly showing the compounder having a funnel
or intermediate container in which source components are placed
either sequentially or concurrently before being transferred to a
final bag;
[0034] FIG. 3 is a perspective view of a second representative
compounder that may be controlled by the method and apparatus of
the presentation.
[0035] FIGS. 4a-4h together comprise a flow chart for controlling
the compounding of a prescribed admixture in accordance with the
present invention.
DETAILED DESCRIPTION
[0036] Broadly stated, the present invention is directed to a
method and apparatus for controlling the compounding of
pharmaceutical admixtures, where the compounding is done by one or
more compounders that may be remotely located relative to the
controller computer or processing means that is interconnected with
the compounders. Referring to FIG. 1, the controller computer or
controller 10 has sufficient memory for storing pharmaceutical data
in the form of a database as well as operating software for use in
controlling compounders and other peripheral equipment. The
computer 10 is preferably a multi-user, multi-tasking computer that
has a communication interface for interconnecting to compounders
12, 14 and 16 and other peripheral equipment such as printers 18
and 20 by communication links 22 that may be wired or wireless, may
be part of a local area network, a wide area network or the
Internet or a combination of the above. The computer 10 may have a
display 23 and keyboard 25 as well as other accessories and
features common to commercially available computers at this
time.
[0037] Other peripheral equipment can include a dumb terminal 24
having a keyboard and display or other input device such as a
laptop computer 26 or other handheld device that is adapted to
enter prescriptions and input instructions for operating the
controller computer software. The compounders may be located in
different areas of a healthcare facility such as a hospital, or on
different floors of a hospital or even at different hospitals. The
compounders 12 and 14 as well as the printer 18 and terminal 24 are
located in hospital B in FIG. 1, whereas the remainder of the
equipment is shown to be located in hospital A. There is preferably
a printer located near each compounder or combination of
compounders, as shown, for printing labels that are applied to the
prescribed admixtures that are compounded. The controller computer
10 is preferably interconnected with a general hospital computer 28
that may be used to prepare and record billing statements among
other functions.
[0038] The present invention is adapted to control compounders such
as compounders 12, 14 and 16. The presence of two machines in
hospital B is to indicate that two different types of compounders
may be used in combination to prepare prescription admixtures, such
as by but one example, the aforementioned AUTOMIX and MICROMIX
compounders. Thus, the compounders 12 may be a compounder adapted
for transfer of high volume additives and the compounder 14 may be
a compounder adapted for low volume additives. Moreover the
compounder 16 may be adapted to transfer both high volume and low
volume amounts of ingredients.
[0039] Referring to FIG. 2, a perspective view of a low-flow module
compounder is illustrated and is adapted to transfer small volumes
of components such as micro-nutrients and other drugs from
individual source containers 30. However, prescription admixtures
may be prepared by a single compounder 16 adapted to transfer high
volume and low volume additives or multiple compounders attached to
a single final bag 46.
[0040] In an embodiment when high accuracy is desired such as when
low volume additives are being added to a PN the fluids from the
containers 30 is transferred through a separate individual fluid
conduit 32 to a single intermediate container of funnel 34 that is
suspended from a load cell assembly 36. The load cell assembly 36
weighs the total weight of the funnel 34 to develop an output
signal, which is indicative of the amount of fluid in the funnel 36
at any given time. The funnel 34 is closed and is connected to a
pressure conduit 38 that is connected to a pressure means and
occlusion means such as a valve 40 by example. The pressure means
is preferably a single peristaltic pump which can selectively
create positive and negative pressures in the funnel 34 to control
the direction and flow of fluid into and out of the funnel 34. The
funnel 34 also is connected to an outlet conduit 42 that extends to
a second occlusion means 44 that is interposed between the funnel
34 and the final bag or container 46. By selectively operating the
occlusion means 40 and 44, and the pressure means, fluid can be
drawn into the funnel and transferred out of it. These same
portions of the machine can also control the direction of flow, so
that fluid can be transferred into the final bag 46 and can be
removed from the final bag for the purpose of rinsing the funnel
34
[0041] A detailed operation of an example of a compounder adapted
to transfer low volume components, at least as of approximately
April 1990 is described in U.S. Pat. No. 5,228,485 which is
assigned to the same assignee as the present invention, and is
incorporated by specific reference herein. The current commercial
MICROMIX compounder may embody certain improvements compared to the
'485 patent, but is believed to be similar to that described in the
patent.
[0042] The compounder 12 may also include an assembly that
transfers the additives utilizing other methods of operation such
as one or more pumping mechanisms and switching mechanism alone or
in combination with volumetric delivery methods, possibly including
calibration such as the compounding devices supplied commercially
by the BAXA Corporation of Englewood, Colo.
[0043] Referring to FIG. 3 a further embodiment of a compounder 50
is represented which is particularly suited for transferring large
volume additives. The compounder 50 includes a number of individual
pumping stations 52 which cooperate with a disposable transfer set
54 to pump fluids from individual source containers 56 to a final
container 58. A detailed operation of an example of a compounder
adapted to transfer high volume components, at least as of
approximately 1999 is described in U.S. Pat. Nos. 4,712,590 and
5,927,349 which is assigned to the same assignee as the present
invention, and is incorporated by specific reference herein. The
current commercial AUTOMIX compounder may embody certain
improvements compared to the '485 and '349 patents, but is believed
to be similar to that described in the patent.
Preparing the Prescription
[0044] In an example of a process for utilizing the preferred
embodiment of the present invention, a physician or other
healthcare provider or group of providers determine what is the
parenteral nutritional needs of a patient and arrive at a
prescription. A pharmacist will then need to convert the
prescription into particular amounts or concentration of additives
in the PN which is to be administered to the patient. These amounts
will vary in dependence on the particular patient. For example the
patient may not be able to accept a large amount of fluid
parenterally and, the nutritional needs will need to be
accomplished within a minimal amount of fluid. One example of a
fluid restricted patient is a neonatal patient. To administer the
desired amount of an additive in a smaller total volume, the level
of concentration of the additive in the final bag 46 may be higher
in the PN than if more of a diluent volume could be used. This
higher concentration may lead to a greater chance of compatibility
problems with other additives in the PN and may exceed acceptable
limits for that patient.
[0045] Referring to FIG. 4a in the preferred embodiment, the
pharmacist enters patient identifying data such as a patient ID
code into the controller utilizing the keyboard 25 (block 70). The
controller 10 then requests and accepts patient specific data
(block 72) from a data storage location such as the computer system
28 of the facility and displays such information on the display 23.
One type of patient specific data which is preferably utilized by
the controller 10 in the preferred embodiment is the patient type
such as premature, neonatal, pediatric or adult, etc. In an
alternate embodiment, the provider enters the patient specific data
directly into the controller 10 or a storage location therein.
[0046] The controller 10 also retains in a storage location
preferred ranges for the acceptable concentration levels of the
different admixtures in a final bag 46. In an embodiment, the
controller 10 may also retain in the data storage location,
concentration ranges for the ingredients for the various patient
types and set the preferred concentration range with a type
dependent range for that particular patient. In a further
embodiment ranges corresponding to patient attributes such as
various patient ages and weights may be retained in the data
storage location and the controller 10 may set the preferred
concentration range with attribute specific ranges.
[0047] In a further embodiment, the controller may also contain an
algorithm for adjusting the concentration range in dependence on
predetermined patient specific factors such as the age of the
patient.
[0048] Thus, in dependence on the patient specific data, the
controller 10 may evaluate whether the preferred ranges are
appropriate for the patient specific type and may then adjusts the
range (block 74).
[0049] The health care provider will then enter the prescription
(block 76) by, for example, utilizing the keyboard 25. In entering
the prescription, the provider will set concentration levels of the
ingredient solutions so that upon compounding the PN will
correspond to the prescription. The controller 10 allows the
prescription to be entered in several different formats. By way of
example the controller 10 may accept inputs of the ingredients in
percent of the final solution, concentration per unit volume or an
amount corresponding to the per unit weight of the patient.
[0050] As the provider is entering the prescription the controller
10 checks the entered concentrations against the determined ranges
(block 78). If a concentration is entered which is outside the
range, an error message is displayed on the display 23. In
addition, if the provider enters an ingredient with an
inappropriate format an error or alarm message is displayed on the
display to alert the health care provider. An example of an
inappropriate format is where the concentration is entered in units
of measure per the patients weight but the patients weight has not
been input as part of the patent specific data.
[0051] In an alternate embodiment, after all the concentrations
have been entered the controller 10 may then review the various
ingredients and highlight with error messages those ingredients
which fall outside the range which has been set for that
ingredient.
[0052] In a further embodiment, templates of various prescriptions
corresponding to various patient types may be retained in a storage
location. The pharmacist or controller 10 may then call up the
template and either accept or adjust the template. In a still
further embodiment, a previous prescription of the patient may be
retained in a storage location. The pharmacist or controller 10 may
then call up the prior prescription and either adjust or accept the
prior prescription to be utilized as the present prescription.
[0053] When an alarm is displayed. Even though the concentration is
outside the range, the concentration may still, in the medical
judgement of a provider, be desired. The controller 10 may then in
certain predetermined instances allow the provider to override the
alarm (block 82). The controller 10 will allow an override upon the
occurrence of one or a combination of certain factors. One factor
is whether the provider entering the prescription has the clearance
to override the particular alarm. Each alarm may require a
different level of clearance before the override is accepted. Some
alarms may not be overridden.
[0054] The identity and clearance level of the provider may be
established by a unique password that is requested by the
controller 10 and entered at an appropriate time such as at the
beginning of the entry of the prescription or at the occurrence of
an alarm (block 84). Other methods of establishing the identity of
the provider are also contemplated such as keycards, retina scans
or the like
[0055] In addition to establishing the clearance of the provider,
to verify that the provider is recognizing and appreciating the
error message and for record keeping purposes. The controller 10
may require that the rationale for the override be entered into a
note screen displayed on the display 23. For certain alarm
situations, the controller 10 does not allow any overrides even
with a rationale (block 86).
Compatibility Groupings
[0056] The preferred embodiment of the present invention evaluates
the compatibilies of the ingredients and the solutions into which
the ingredient comes into contact during the compounding process
and also the solution in the final solution bag 46 after the
compounding is complete.
[0057] In present practice, the evaluation of the final prepared PN
is a process that is routinely performed by pharmacists. The
pharmacists compare the components of the final prepared admixture
to literature, which has information concerning compatibility. Many
times, the literature is not sufficiently specific to the exact
type of ingredients in the admixture being prepared, which requires
the pharmacist to use professional judgment in deciding whether the
resulting admixture will be compatible.
[0058] In accordance with the present invention, the overall
compatibility evaluation for complex admixtures primarily focuses
on the compounding of parenteral nutrition, which broadly includes
PN screening and calcium phosphate solubility screening.
[0059] The process preferably involves a first screening step of
comparing all PN additives to limits set by the controller 10 which
may include the steps of setting ranges preferred concentration
limits as described above.
[0060] A second step involves comparing the final concentration of
amino acids, dextrose and lipid based components to the database of
tested admixtures. Amino acid comparisons are brand specific.
Databases of admixtures have been compiled through the testing of
admixtures and also by utilizing published literature. The
admixture database preferably comprises concentrations for both
stable and unstable admixtures with a notation of the study
conditions such as time and temperature. Preferable the database
includes admixtures having identified source components such as by
example, brand named amino acids.
[0061] In the second step, the prescribed admixture is compared to
the database of admixtures. Preferably the comparison is first
carried out against admixtures having identified source components.
If the prescribed admixture falls within some range of a stable
admixture the present invention proceeds to the next step without
generating a notice to pharmacists. The range may be set by some
variance amount, for example by a set percent of the amounts or
concentration levels of corresponding base components in a stable
admixture.
[0062] However, admixtures with matches (or mixed stable and
unstable matches) to the unstable formulation contained in the
database (to preferably plus or minus a set variation of the
amounts of base components) and yet have passed the first screening
step may be designated as potentially unstable.
[0063] In an embodiment of the present invention, if the prescribed
admixture matches an unstable admixture a further step may be
performed such as screening whether the study conditions of the
matched admixture are equivalent to the present conditions. The
present invention provides a warning to pharmacists that the
admixture is equivalent to potentially is unstable admixture under
the study conditions of that admixture.
[0064] In a further embodiment, admixtures that do not match any
stable or unstable admixtures contained in the database are
re-evaluated. When this is done, the amino acid brand is ignored
and the admixture is then compared to the entire database. The
results of this comparison are handled following the same steps
that have been previously described. Preferably, the pharmacist
would be provided a warning about the ignoring of the amino acid
brand of the database admixture. If the admixture does not match
the database after re-evaluation of the entire database, the
present invention will provide a warning notice to the pharmacist
that no similar PN has been previously tested.
[0065] With regard to calcium phosphate solubility screening, the
solubility of calcium salts and phosphate salts in the same
solution is dependent on many variables including, but unlimited to
concentration, temperature, salt form, order of mixing, pH, amino
acids concentration, other additives and time. It has been the
practice in the prior art for the pharmacist to compare the final
concentration of both the calcium salt and phosphate salt to a
solubility curve that is specific to a given amino acids brand and
final concentration
[0066] In the present invention, the calcium phosphate solubility
screening in a complex compounding process is achieved by the
controller 10 comparing the final concentration of both the calcium
salt and phosphate salt to a matrix of known compatibility. The
matrix may be input into a storage location by the Pharmacist or
previously input into the database The present invention uses the
matrix to sort compatibility by the amino acids brand and final
concentration. For example, a calcium phosphate solubility matrix
for a specific amino acids brand may have compatible concentrations
of calcium salts and phosphate salts for a 1%, 2% and 4% final
amino acid concentration. The present invention determines the
limits of solubility that have been exceeded and will generate a
warning to the pharmacist if it has.
[0067] In a further embodiment, the controller 10 may generate and
display on the display 25 a graph of a shape representing the
calcium phosphate solubility for that a particular amino acid and
may also present a designation of the prescribed admixture relative
to the solubility shape to assist the pharmacist in achieving a
prescription which is compatible.
[0068] However, in addition to the determining whether the
prescription present in the final bag is compatible, compatibility
during the compounding process must be evaluated. For example, the
compatibilities of a solution with a second solution at the time of
contact must be evaluated. The second fluid may be found in a
common conduit, intermediate mixing chamber or final bag. To
overcome this potential problem the pharmacist may adopt gross
rules for the compounding process. For example it is common
practice that all diluent volumes are added to the final bag first
so that all additives which are present in the final bag are
diluted as much as possible at the time of the addition of an
additional ingredient to the final bag. However, such a practice
reduces the ability to rinse from such a diluent during the
compounding process.
[0069] In accordance with an important aspect of the present
invention, the controller computer 10 may utilize the known
compatibilities of components to enable concurrent compounding of
such compatible components into the final bag or an intermediate
mixing chamber. In addition, rinsing may be accomplished with a
source solution which is compatible with both the solutions flowing
through the rinsed portion before and after the rinsing. Thus,
large volume additives may be transferred to the final container or
bag or transferred to an intermediate mixing chamber at the same
time as small volume additives or used as rinsing fluids. Such
compatibility screening and concurrent compounding enables the
present invention to maximize the speed in which admixtures are
compounded which results in more efficient use of the compounders,
as well as the controller computer.
[0070] In accordance with an important aspect of the present
invention, testing of components for compatibility characteristics
is used to build a database that includes a plurality of groups,
which represent concentration dependent compatibility on the basis
of testing of components. In an example, there are seven groups of
components identified in Table 1 set forth below, based upon the
current knowledge. It should be understood that many more groups of
components may be defined as greater knowledge about compatibility
characteristics of various ingredients are acquired, even to the
extent of having a group for each individual component, or even
separate groups for the same component in different
concentrations
TABLE-US-00001 TABLE I Group Compatibility Group Compatible
Incompatible 1 1, 2, 3, 6 4, 5, 7 2 1, 2, 3, 4, 6, 7 5 3 1, 2, 3,
4, 6 5, 7 4 2, 3, 4, 6 1, 5, 7 5 6 1, 2, 3, 4, 5, 7 6 1, 2, 3, 4,
5, 6, 7 -- 7 2, 6, 7 1, 3, 4, 5
[0071] The compatibility groups may be known based on test results
and are contained in the database of the controller computer so
that the compounding process can be carried out with the
information in the database. It is preferred that the database be
located only in the controller computer, rather than be distributed
to various locations so that it can be reliably controlled, managed
and modified as additional knowledge and information is gained
through history, continued testing, and the addition of other drugs
and components to the database.
[0072] In a preferred embodiment of the present invention, based
upon the database, the controller will logically group the fluids
in the source containers 30 (FIG. 2) into the compatibility groups
regardless of their physical placement on one of the compounder 12,
14, 16.
[0073] In a further embodiment of the present invention, the
controller shall calculate for a particular prescription, the
number of groups present and the sorting of the groups into sets of
compatibility groups between which a rinse is required such that
the total number of rinses is minimized.
[0074] In a still further embodiment of the present invention the
controller utilizes other inputs such as physical restraints of the
system to determine the proper compounding sequence to more
efficiently utilize source solutions as rinses as opposed to rinses
from the final bag. Examples of a physical restraint may include
the volume of an intermediate chamber or funnel 34 and the rinse
volume for such a chamber.
[0075] In an example, the intermediate chamber has a funnel with a
volume of 60 ml and a rinse volume requirement of 30 ml. If the
prescription calls for 5 ml of Group 1, 20 ml of Group 2; 20 ml of
Group 3; 55 ml of Group 4 and 40 ml of Group 6, the controller 10
may adopt a compounding order of Group 1, Group 2, Group 3, Group 6
and Group 4 instead of ascending sequence.
[0076] By partially filling the funnel 34 with just Groups 1, Group
2, Group 3, and 10 ml of Group 6, then draining the partially
filled funnel before the addition of the remainder of Group 6, at
least 30 ml of Group 6 fluid is remaining after the funnel 34 is
first filled and this Group 6 fluid can serve as a rinse thereby
removing the need to rinse from the final bag.
[0077] Other examples of sorting relationships or algorithms may be
defined and implemented by the controller to accomplish the desires
of the users, such as allocating the volume of a group to other
compatible groups to reduce the number of draining of the chamber
or funnel 34 may be minimized.
[0078] In this regard and reiterating what was stated above, while
seven separate groups are contained in Table 1, it is expected that
additional groups will be defined, which may be based on more
sophisticated knowledge and testing. The precise number of groups
will eventually be a function of the sophistication of
compatibility knowledge vis-a-vis the all other components that are
used, and it is contemplated that a significantly larger number of
groups will be defined.
[0079] This will lead to the controller computer being able to more
accurately control the compounding steps that will result in yet
increased efficiency and speed of compounding. Additionally, the
database may be considered to be proprietary as its sophistication
increases and control of the database at a single location is a
significant protection that would not be present if the database
were to be distributed to a processor in each compounder, for
example.
Compounding Strategies
[0080] In a further embodiment of the present invention a mixing
strategy or method which recognizes the possibility of liquid
hazing and utilizing preferably minimizing rinses from the final
bag is shown in FIGS. 4b-4h, which illustrates the preferred
embodiment of a method of defining the operation of at least one
compounder to provide a nutritional formula admixture. The start
(block 100) of the method or process is shown in FIG. 4b and occurs
after prescriptions have been entered into the controller
computer.
[0081] In an alternate embodiment of the present inventions the
prescription are initially screened by the controller 10 in one or
more of the methods described above.
[0082] The next step is to decide the compounding strategy (block
102) which is in part dependent upon the kind of compounding
equipment that is present.
[0083] In this regard, and as previously mentioned, a hospital,
other healthcare facility or pharmacy may have only a high-flow
module compounder 12 (FIG. 1) which is adapted to transfer high
volume fluids at a relatively high flow rate. However, in the event
that the facility also has a low-flow module compounder 12, then it
can transfer solutions at a low flow rate, which generally enables
very small volumes or amounts of a component to be added to a bag.
Therefore, in instances where particularly adopted high volume and
low volume compounders are utilized, the controller decides
compounding strategy (block 2) determines which strategy to employ.
The program is adapted to control either a high flow rate (block
104) which would control a high-flow module compounder for example,
a low flow rate (block 106) which would control a Low-flow module
compounder, for example, or a high and low flow rate (block 108)
which would result in both machines being used or for a single
compounder 16 suitable for both high volume and low volume
transfers, for example.
[0084] Referring initially to the high flow only, the controller
performs initial compounder calculations for high flow only
compounder set up (block 104) which comprises several calculations
that the program is will execute for each large volume component
that will be part of the final bag. This includes the calculation
based on specific gravity to convert volume measure to weight
measure, if the transfer is carried out by utilizing the weight of
a component that is transferred rather than volume that is
transferred. In this regard, a prescription may be written using
measurements that are input by grams or milliliters or a percentage
of the final solution and the software may be required to convert
the measurements to weight, if the compounders transfers in
dependence on the sensed weight of the transferred component. For
example, the high-flow module 14 and low-flow module compounders 12
compound utilizing the weight or change of weight of an
intermediate or final container.
[0085] After the calculations are made, line 110 extends to FIG. 4c
where a determination is made whether a prescription containing
lipids should have the lipids transferred to the final bag first
(block 112), which is a user setting. In this regard, users may
wish the lipids to be first or last into the final bag, which is
strictly an option that the user can specify. Such specification is
preferably based on criteria that is set up initially before the
compounder is ever run in a facility.
[0086] This involves the sorting of all the additives into
compatibility groups and this may be done by grouping common
compatibility components as shown in the Table 1 above. If lipids
are transferred first in the final bag, a determination of the
number of compatibility meta-groups is made and the number of
rinses N that will be required (block 114) and then the program
specifies a sequence of large volume transfers with lipids first.
Once the sequence is determined, then line 118 extends to FIG. 4d
where the instructions for operating the compounder are transferred
to the compounder (block 120).
[0087] Alternately the controller 10 can transfer the fluids
utilizing other user settings including settings reflecting the
general rules of mixing TPN's (blocks 116, 124). With regard to the
general rules of mixing total parenteral nutrients, they include
the following:
[0088] 1. Phosphate salts are added before calcium salts.
[0089] 2. The determination of calcium phosphate solubility should
be made based on the volume of solution in the TPN bag at the time
calcium is added.
[0090] 3. Unless lipids are required as the last additive, calcium
should always be the last additive to the TPN bag, holding out one
rinse, if possible.
[0091] 4. Compatibility groups are numbered sequentially to
coincide with the order of mixing unless specific exceptions are
identified.
[0092] If the compounder 14 has separate conduits to the final bag
for each of the source solutions, the controller 10 sets the order
of pumping to insure that the fluid is added to the final bag. The
primary determination of the pumping order is the compatibility of
the fluid entering the bag with the fluid present in the bag.
[0093] Returning to FIG. 4c, if the lipids are not first in the
final bag, the number of compatibility groups is also determined,
as is the number of rinses required (block 122). The sequence of
transfers and rinses with lipids last is determined and executed
using one or more of the compounding methods. The final step shown
by line 126 that extends to FIG. 4d results in the transfer
instructions being sent to the compounder (block 120).
[0094] Turning now to the low flow only path which begins with the
initiating compounding calculations for low flow only (block 106),
this would be used for compounding admixture prescriptions that
would be done with a Low-flow module compounder, for example. Even
though it is likely that a high flow compounding apparatus would
exist in the same area, it is common to choose the low flow
compounder if the volume that is going to be added to the final bag
is relatively low, such as would occur for a neo-natal prescription
or for a very small infusion.
[0095] An initial determination is made whether the final bag
already contains lipids (block 130). The reason that this
determination is made is that there may be a prescription that is
compounded in two stages with large volume flow components already
being transferred to a bag and the bag is then placed on the
Low-flow module for transferring micro-nutrients into it. If lipids
are already in the bag, that will make a difference as to how
rinses from the final bag are made into a funnel or intermediate
mixing chamber which may be present in a low-flow module
compounder.
[0096] The program determines from the prescription whether lipids
are contained in the bag and if so, the entire admixture
prescription is checked to determine if lipids are in or will be in
the final bag. If they are, then the inquiry is made as to whether
the user cares whether there is lipid haze in a following admixture
prescription (block 132). This is due to the fact that if any rinse
is performed using fluid from the final bag some of the lipids will
stay behind in the funnel. These lipids may be transferred to a
number of the following bags and in an amount sufficient to produce
a visible haze in the solution. If the present bag is made with
lipids and the next bag does not have lipids and no rinse of
surfaces which will come into contact with the contents of both
bags occurs, then there is a possibility that the lipids would haze
the next bag, particularly if the prior bag utilizes a rinse from
the final bag. In the event that the facility does not desire lipid
haze, then the compound will not be prepared at that time but will
remain in the queue to be compounded at another time (block 134).
If the hospital accepts lipid haze, then a warning is printed by
the printer (or by a visual display) indicating that there is a
possibility that lipid hazing will exist in the funnel (block
136).
[0097] If the final bag does not contain lipids (block 130), or if
they do contain lipids but do not care about lipid haze (block
136), then using the solubility and compatibility tables and
proceed to calculate the compound keeping in mind that rinses will
be from the final bag (block 138). This step is intended to perform
calculations that are designed to minimize the number of rinses to
maximize efficiency and may utilize one of the methods described
above. When this is done, line 140 extends to FIG. 4d and the
transfer instructions to the compounder are then sent to the
compounder (block 142).
[0098] Turning now to the high and low flow branch shown in FIG.
4b, the initial step is to initiate the compounding set up (block
108) which requires the converting calculations be carried out that
have been described with respect to the high flow only routine
(block 104) and line 144 extends to FIG. 4c, where the number of
compatibility groups and rinses is determined (block 146).
Basically, it is a determination as to whether there will be a
problem with the prescription if it is compounded in the way that
it is written
[0099] The determination is made as to whether lipids are included
in the final bag (block 152). If lipids are required, the
determination is made whether lipids are to be transferred first,
last or otherwise optimized (block 154). Whether lipids are
required to be first, last or optimized is a user preference that
is programmed in the sense that the user defines this once and it
is thereafter not prescription dependent. Optimize usually always
means that lipids would be placed first. Thus, the criteria for
compounding that is established by the user initially will
determine the path of steps taken. If they are first or optimized,
then line 156 extends to FIG. 4d and FIG. 4c to a step that will be
described later. If lipids are not included in the final bag, then
line 158 extends to FIGS. 4d and 4e for steps that will also be
described later. If lipids are required to be last, then line 160
extends to FIG. 4d and the determination is made whether the
prescription is stable without the lipid volume (block 162).
[0100] If the prescription is not stable without the lipid volume,
the program alerts the user that the prescription cannot be
compounded if lipids are last and that a pharmacist check may be
required (block 164). The program then determines whether lipids
can be transferred into the final bag first (block 166), which if
not, results in the compound not being prepared (block 168). If the
lipids can be transferred first, then line 170 extends to FIG. 3d
wherein the number of rinses including the volume of lipids and
lipids will be transferred to the final bag first (block 172).
[0101] Returning to block 162, if the prescription is stable
without including the lipid volume, then the program calculates all
solubilities including the volume of lipids and the lipids will be
transferred to the final bag last (block 174) (FIG. 4d). The
calculation of solubilities not including the volume of lipids
(block 174) is done to calculate the calcium phosphate solubility
based on possibly less volume than what was included in the
original screening. Therefore, for example, if there were 50
milliliters of lipids in a 200 milliliter total volume PN, then the
phosphate calcium solubility evaluation would be done on 150
milliliters.
[0102] After the compatibility groupings and rinses are calculated
(blocks 172 and 174), the program then determines whether the total
volume excluding lipids is more than the funnel volume (block 176).
If yes, line 178 extends to FIG. 4f where the program determines
whether lipids are first (block 180) which if yes, results in the
program determining whether the number of rinses of a source rinse
of base may be held for a rinse in an acceptable sequence (block
182). If it can, the program breaks into compatibility groups and
proceeds with compounding with required rinses coming from the
selected source container (block 184) and the instructions are
transferred to the compounder (block 186). As described above the
steps that are described in blocks 182 and 184, while identified as
separate steps in the flow chart, are really in actuality
interrelated. This is because the number of rinses is a function of
the compatibility groups and the compatibility groups must be
determined in order to identify where rinses should occur as
described earlier.
[0103] If the total volume excluding lipids is not more than the
funnel volume, then the completion of the compounding is done using
the low-flow module and can be done in the funnel of the low-flow
module compounder. The program determines if a source rinse volume
of a component solution can be held back for a final rinse (block
188) which if yes, results in holding back when source rinse volume
of a base component and all other ingredients are compounded in the
funnel and transferred to the final bag and the funnel is then to
be rinsed with the reserve base (block 190) with the rinse
transferred to the final bag and transfer instructions are sent to
the compounder (block 192).
[0104] In order to determine whether a source rinse volume can be
held back, it is necessary to screen the fluid present during
mixing in the funnel without the diluting effect of the rinse to
see if it is permissible to hold anything out, i.e., whether the
resulting admixture will be stable. Also, the capacity of the
funnel is important with regard to the volume that can be held out
for doing a complete rinse. For example, if the funnel capacity is
50 milliliters and only 30 milliliters can be held back, then there
will not be a full funnel rinse and the decision as to whether this
is adequate or not can be made from the user. It is also
contemplated that the method of rinsing will see to have the final
rinse originate from a source component such as sterile water,
dextrose or amino acids and that intermediate rinses may be made
using solution from the final bag with the source rinse of a
component volume being held back for the final rinse so that the
funnel would be cleaned as much as possible.
[0105] If there is not sufficient source rinse volume, the program
determines whether any amount of the source rinse volume can be
held back for a final rinse (block 194) which if yes, it is done,
and all other ingredients are compounded in the funnel and it is
rinsed with the reserve base (block 196). The transfer instructions
are then sent to the compounder (block 198).
[0106] If there is no amount of source that can be held back for
the final rinse, all ingredients are then compounded into the
funnel without any rinse (block 200) and instructions are sent to
the compounder (block 202).
[0107] It should be appreciated that from block 152 if the answer
is that there are no lipids in the final bag, then the path through
the flow chart assuming that the total volume is in excess of the
funnel volume results in the determination of whether lipids are
first in block 180, which really is not applicable because lipids
are not present. In this case, the steps 182 and 184 may be carried
out with the source rinse being from source container and/or the
final bag. As described above the controller will preferably
utilize rinsing and compounding sequence which eliminates the need
to rinse from the final bag
[0108] Returning to block 204, if the answer is no, or if the
admixture contains lipids, the lipids are to be transferred first
and a rinse from a final bag is required (block 182) the program
determines if lipids may be transferred last (block 206) which if
not, the program inquires whether lipid haze is acceptable (block
208), which if not, results in the compounding not be continued
(block 210). If it is acceptable, the program produces a warning
about lipid haze (block 212).
[0109] If the lipids can be transferred last, then the program
determines whether the number of rinses of the source rinse can be
held for a rinse and an acceptable sequence can be carried out with
one rinse originating from the final bag (block 214). If it can,
then the prescription is analyzed for compatibility groups and
compounding will proceed with the rinses occurring at the
appropriate times with preferably the next to last rinse being done
with the final bag with all others from the source components
(block 216). In this manner upon rinsing with the contents of the
final bag, the ingredients present in the final bag will be diluted
as much as possible while allowing for a final source container
rinse. The instructions are transferred to the compounder (block
218).
[0110] If the answer from block 214 is no, line 220 which extends
to FIG. 4g results in the program determining if the number of
rinses minus 2 (N-2) times the source component rinse can be held
for a rinse in an acceptable sequence with two rinses from the
final bag being determined (block 222). If yes, then the
compatibility group step is again executed (block 224) and
instructions to the compounder are issued (block 226). If no, then
another determination is made for the number of rinses minus 3
(N-3) (block 228), with compatibility analysis being done if yes
(block 230) and transfer instructions are sent to the compounder
(block 232). If no, the determination is made regarding N-4 (block
234). If the determination from block 234 is yes, the compatibility
analysis is again conducted (block 236) and the instructions are
transferred to the compounder (block 238). If the determination is
no on line 240, the program then determines if a source rinse can
be held for a final rinse (block 242) which if yes, results in the
compatibility analysis being carried out once again (block 244) and
the compounding instructions being issued (block 246).
[0111] If no, the program determines if any amount of source
solution can be held back to make the required volume excluding
lipids below the funnel volume (block 248). If the answer is yes,
then that appropriate volume is held back and the ingredients are
compounded in the funnel and the held base component is used to
rinse the funnel (block 250) and the transfer instructions are
issued to the compounder (block 252). If not, the program
determines if lipids are in the prescription (block 254), which if
not, results in the program compounding with all rinses originating
from the final bag (block 256) and the instructions are issued to
the compounder (block 258) but if lipids are present, the program
determines whether lipid haze is cared about (block 258). If not, a
warning is issued (block 260) and if it is, the compound will not
be prepared (block 262). After issuing the warning, the compounding
proceeds with all rinses from the final bag (block 256) which
results in the transfer instructions being sent to the compounder
(block 258).
[0112] In sending the instructions to the compounder (blocks 192,
186 etc) the compounder and controller may utilize several methods
and adaptations to perform the compounding. For example the
controller 10 may send instructions to a controller included as a
part of the compounder 12, 14, 16 or the controller may directly
operate the compounder or any combination or similar method.
[0113] In addition to the compounding strategies that are carried
out in the manner described in connection with the flow charts of
FIGS. 4a through 4h, there are other functionalities that are
carried out by the present invention. In this regard, the
controller computer 10 is adapted to examine the composition of
each prescription admixture that is present in a queue of such
prescription admixtures for which instructions are sent to the
compounder that is to prepare the admixture. By examining the
components of each prescription admixture in the queue to determine
those admixtures which contain lipids, for example, those
admixtures which do contain lipids can be group together in order
so that lipid hazing is not a concern until the last of the lipid
containing admixtures is prepared.
[0114] As described in U.S. Pat. No. 4,653,010 prescription
admixtures residing in queues may be sorted and grouped around
common components. In an embodiment of the invention other desired
groupings of admixtures such as by patient type can be determined
in a similar fashion. Such reordering of the prescription
admixtures in the queue can have the effect of increasing the
throughput due to the needs and requirements of a facility.
[0115] Another important aspect of the present invention involves
the ability of the computer 10 to adjust for a user defined
overfill volume by increasing the volume of each of the components
that are to be added to the prescription admixture by a
predetermined amount to achieve an admixture of equal prescription
but a slightly higher volume, and thereby compensate for volume
that is required to prime an administrator set or address accuracy
concerns when the prescription call for extremely small
concentrations of an admixture so that the correct amount of the
component in the desired concentration will in fact be delivered to
the patient.
[0116] Yet another important aspect of the present invention
involves the capability of the computer 10 to receive a user
switchable option, which when activated, enables a diluted higher
concentration ingredient to be substituted for a prescribed lower
concentration ingredient. In many instances where the patient is
not fluid constrained diluting a higher concentration solution with
a compatible rinse solution such as sterile water will produce the
prescribed admixture with the minimum amount of potential
instability. In a further embodiment of the present invention,
particularly when the patient is fluid constrained, the stability
of the admixture in eliminating or minimizing the diluting solution
by considering other ingredients as diluting fluids is determined
by the controller 10 which may employ one of the methods described
above to determine stability during and after compounding
[0117] In a further embodiment of the method of the present
invention, a compounding strategy for overfilling of the final bag
46 may be performed. As described previously, overfilling may be
desired to compensate for the amount of admixture, which may not be
administered due to the system of administration. For example some
portion of the solution may be retained in a final bag even after
administration.
[0118] In keeping with an aspect of the present invention, the
desired method of setting the overfill may be particularly
configured. By way of example the overfill volume may be set in
absolute amounts, by a percent or so that the final bag will have a
specific desired volume. In preparing such a prescription, the
method calculates the new amounts of ingredients required to
achieve an admixture substantially equivalent to the prescribed
admixture but at a slightly greater volume.
[0119] Upon determining the proper ingredient amounts of the
ingredients, the controller 10 may check the resulting admixture
against various criteria to determine if the resulting admixture
may be administered. For example for a fluid restricted patient, an
overfill may generate an admixture with an amount of fluid in
excess of the allowable amount. An alarm may be generated an error
message may be displayed to the user.
[0120] In a further embodiment, the controller 10 may adjust or
suggest the adjustment of the volume of the admixture to avoid
having one or more of the ingredients in an amount less than a
predetermined level is such as that which corresponds to the
minimum accuracy amount suggested for a compounder 12, 14, 16. By
way of example, the amount of a component may be 90% of the minimum
suggested amount. The controller may then increase the total volume
of the admixture such that the amount of the component reaches the
minimum suggested amount and indicate to the user that only of a
portion of the resulting admixture is to be administered to the
patient.
[0121] In should be understood that the arrangement of the steps in
the various preferred embodiments of the present invention may be
altered. For example the stability of the final admixture may be
determined before or after the determination of the proper
compounding strategy.
Reporting
[0122] The compounder 12, 14, 16 may communicate to the controller
10 during and after the compounding process. For example, should a
sensing device as described in U.S. Pat. No. 5,927,349,
incorporated by specific reference herein, detect an incorrect
source solution flowing through one of the conduits 32 an alarm may
be communicated. Similarly, during and after compounding the exact
quantities of the ingredients transferred to the final bag 46 may
be transmitted to the controller 10
[0123] Upon receiving the amounts of the ingredients transferred
during compounding, the controller 10 may present cost data to the
pharmacist or communicate such data to the hospital computer system
28. The controller 10 may adjust the cost data to reflect the
actual cost of providing the admixture. By way of example, some
ingredients may come in containers which can only be accessed once
before discarding. Thus if such an ingredient is used in an amount
less than that in a container, the controller 10 will indicate the
cost of the entire container as opposed to that portion of the
ingredient used in the admixture.
[0124] From the foregoing, it should be appreciated that an
improved method and apparatus for controlling the preparation of
parenteral admixtures has been described, which results in faster,
more efficient preparation of the same without sacrificing safety
in any way. Moreover, several of the features provide added
safeguards. The present invention employs an extensive analysis of
admixture components and utilizes known characteristics of
components in a novel fashion to control compounders so that such
prescription admixtures can be reliably and safely prepared without
violating known rules of preparation, but also in a manner
consistent with certain user defined preferences.
[0125] It should be understood that various changes and
modifications to the presently preferred embodiments described
herein will be apparent to those skilled in the art. Such changes
and modifications can be made without departing from the spirit and
scope of the present subject matter and without diminishing its
intended advantages. It is therefore intended that such changes and
modifications be covered by the appended claims.
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