O47
A Pilot Study to Investigate the effect of Routine Warming On the Level of a Glucose Degradation Product (GDP) in
Conventional Peritoneal Dialysis (PD) Fluids in a Clinical Environment.
Judge, C.G
Kent Kidney Care Centre, East Kent Hospitals NHS University Foundation Trust
INTRODUCTION: Conventional, lactate- based PD fluids are commonly used in the UK today. Heat sterilisation
during manufacture causes GDPs to rise to toxic levels. A maturation period of several weeks is required for them
drop to acceptable levels for clinical use. The most toxic GDP that has been detected is 3,4-di-deoxyglucosone-3ene (3,4 DGE), which is associated with delayed healing, reduced cell proliferation and cell death, even at low
concentrations. While it is known that 3,4 DGE levels rise when warmed during laboratory experiments, across a
range of temperatures and glucose concentrations, it is not known if this effect occurs in the routine clinical
environment of the PD department. This simple pilot study compares levels of 3,4 DGE over time, in batchidentical pairs of PD bags that are either warmed to 36.5 degrees, or left at ambient (room) temperature.
METHODS: Six unopened boxes of PD fluids bags from 6 different batches and sterilization dates were selected,
two for each glucose concentration (conc); low (1.36%), medium (2.27%) and high (3.86%). A pair of bags were
taken from each box, and labeled either ‘warmed’ or ‘room temperature’. The different batches were recorded A-F,
12 bags in total were prepared. At zero hours (before warming commenced) fluid samples were taken from each bag
using aseptic technique. Then for each pair of bags, one was placed in the department bag warmer (set at 36.5
degrees Celsius) and the other on a trolley. The Ultraviolet absorbance at 228 and 284nm was recorded using the
spectrophotometer at the Trust’s pathology department. The concentration of 3,4 DGE in micromols/l for each
sample was calculated using an accepted formula from the literature. Sampling was repeated after 24 hours of
warming and then weekly for 8 weeks. The results were plotted on a graph and analyzed using Microsoft Excel.
RESULTS: At zero hours, the batch pairs showed comparable levels of 3,4 DGE, but there were differences
between batches at each glucose concentration. After 8 days of warming, the levels of 3,4 DGE in all the warmed
bags had increased by a minimum of 25% and maximum of 31%. The controls left at room temperature rose by
between 2.86% to 5.33%. It was notable that the 3,4 DGE level of the warmed bags rose rapidly in the first 8 days,
and thereafter plateaued, although warming continued at 36.5 degrees Celsius for several weeks (3 weeks shown
here).
Conc/Temp0C/ Batch
1.36%/ 36.5 /
A
1.36%/ ambient/ A
1.36%/ 36.5 /
B
1.36%/ ambient/ B
2.27%/ 36.5 /
C
2.27%/ ambient/ C
2.27%/ 36.5 / D
2.27%/ ambient/ D
3.86%/ 36.5 /
E
3.86%/ ambient/ E
3.86%/ 36.5 /
F
3.86%/ ambient/ F
3,4 DGE Day
0
37
36
40
39
69
70
59
59
101
105
93
97
3,4 DGE day 1
39
41
42
44
74
75
62
63
105
108
97
99
3,4 DGE day 8
47
38
51
41
88
72
77
62
127
110
119
100
3,4 DGE day
15
48
38
52
42
89
73
78
62
127
108
120
102
3,4 DGE day
22
48
37
53
42
89
72
78
61
130
107
121
101
CONCLUSION: This small pilot study, part of a masters project, demonstrates that routine warming in a clinical
area can cause rapid elevation of 3,4 DGE in 8 days or less. While the statistical significance of this finding cannot
be demonstrated with such small numbers, it is notable the levels of 3,4 DGE found here are higher than those found
by others- even before warming commenced. All 6 warmed bags showed the same response. The levels of 3,4 DGE
found have been associated in the literature with toxic effects as noted above.
RELEVANCE: PD fluid warming practices vary, but informal feedback suggests bags are often heated for
extended periods. In an unpublished survey of 35 UK units (part of the same masters project) respondents from 12
units felt it was acceptable to warm bags for timescales ranging from 7-14 days, to > 6 weeks, and 8 units didn’t
know how long their bags were warmed. PD fluid is classed as a borderline product, governed by medicines
legislation. It should be stored as directed, at or below 250C. PD staff should be made aware that simple adjustment
of bag warming practice could reduce patient exposure to 3,4 DGE. GDPs change in response to the temperature of
their environment; this has implications for storage areas in hospitals, which may lack ventilation, and of course
countries with high seasonal or year-round temperatures.