Hospital Pharmacy - December 2017 - 767

767

Pereira et al.
Table 1. Supplies for Del Nido Cardioplegia Solution Preparation (Weight/Volume [w/v]).
Supplies

Initial concentration
a

Plasma-Lyte A 7.4
Sodium bicarbonate USP
Mannitol USP
Magnesium sulfate USP
Lidocaine USP
Potassium chloride USP
Final compounded volume

-
8.4% w/v (1 mEq/mL)
20% w/v (0.2 g/mL)
50% w/v (0.5 g/mL, 4 mEq/mL)
1% w/v (0.01 g/mL)
2 mEq/mL

Volume (mL)
1000 (1 bag)
13
16.3
4
13
13
1059

Baxter Healthcare Corporation, Deerfield, Illinois.

testing under ideal storage conditions, as outlined in USP
7979 also needs to be investigated. This report aims to satisfy
both needs.
The del Nido modified depolarizing cardioplegia solution
is a crystalloid-based preparation containing sodium bicarbonate, mannitol, lidocaine, magnesium sulfate, and potassium as additives in a balanced electrolyte solution. The
sodium bicarbonate acts as a pH buffer to assist with excess
hydrogen ions in the arrested heart; the mannitol is a free
radical scavenger which also maintains osmotic pressure;
magnesium sulfate prevents contractile activation by acting
as a competitive calcium channel blocker; lidocaine in local
high dose, acts as a sodium channel blocker, preventing electrical activity and promoting spontaneous defibrillation; and
potassium chloride depolarizes the myocardial cell membrane.2 The final product intended for coronary perfusion is
used in a ratio of 4 parts crystalloid solution to 1 part patient
whole blood, and is most often administered antegrade in a
cold blood and single-dose fashion.2

Hospital Pharmacy Compounding
Process
All compounding takes place in an ISO 5 (ie, laminar airflow
hood) located within an ISO 7 buffer area. All ingredients are
USP/NF-certified commercially available products, and no
nonsterile ingredients are used during the compounding process (Table 1).
All compounding manipulations were performed by certified pharmacy technicians using appropriate aseptic technique under the continuous direct supervision of a registered
pharmacist. Each ingredient was sequentially transferred
into sterile empty 1-liter ethylene vinyl acetate (EVA) containers using the EXACTAMIX automated compounding
system (Baxter Healthcare Corporation, Englewood,
Colorado) per the manufacturer's instructions. As this compounder is also used for the preparation of parenteral nutrition solutions, prior to beginning the compounding process,
a special configuration for ingredient placement on the
device specific to the cardioplegia preparation was activated
on the system. As an additional safety measure, each ingredient was bar coded and scanned to match with its position on

the compounder. In the case of lidocaine 1%, the solution
was repackaged from its original source container into a sterile, 60-mL syringe and labeled with appropriate bar coding
and checked by a registered pharmacist prior to placement on
the compounder. Once the device was set up, the compounder
was calibrated and checked by a registered pharmacist. Each
sterile empty EVA bag was labeled prior to placement on the
compounder using labels generated by the Abacus software
(Baxter Healthcare Corporation, Englewood, Colorado) program that interfaces with the EXACTAMIX compounder.
Each bag was individually compounded and weighed at the
completion of the compounding cycle, and compared with
the calculated final expected weight. Only bags whose final
weights were within a ±2% margin were considered acceptable and all others would be discarded. In addition to
observing the entire compounding process as it occurred,
pharmacists also visually inspected the final product for the
correct volume and any evidence of visible particulate matter. Furthermore, the pharmacist reviewed the automated
report generated by the compounder for any additive
delivery malfunction (ie, formation of bubbles), source container changes, and confirmation that the weight of each bag
was within the desired ±2% range. Both pharmacist and technician signed the manufacturing log and product label associated with the final compounded product. All bags were
stored under refrigeration at 4°C in a dedicated quarantine
refrigerator until the quality control (QC) results, described
below, were known. Given our high cardiac surgery case volume, a batch of 33 bags is usually compounded weekly during a single compounding period.
As part of the in-process QC, 3 of the 33 weekly bags are
randomly selected postproduction and assayed for potassium
content as an indicator. A sample of 5 mL of dNCS was aseptically withdrawn using a 10-mL syringe, which was capped
and labeled with the bag serial number and preparation date.
It was then sent to the institution's clinical chemistry laboratory for analysis. As per the agreement with the laboratory,
all samples were batch processed and the results were
reported to the pharmacy within 90 minutes of reception. A
different pharmacist not involved in the compounding
process reviewed the laboratory results prior to the release of
each batch of dNCS to the surgical team. The laboratory

Table of Contents for the Digital Edition of Hospital Pharmacy - December 2017