Gauging the temperature of the glucose used in the cryosclerotherapy *
(Portuguese
PDF version)
Marcos
Victor Ferreira,1 Amélia Cristina Seidel,,2
Leandro V. Fregadolli,3 Carlos E. Borghesan,3
1.
MSc. Assistant professor, Operative Technique, Universidade Estadual
de Maringá (UEM), Maringá, PR, Brazil.
2. Ph.D. Adjunct professor, Angiology and Vascular Surgery,
UEM, Maringá, PR, Brazil.
3.
Sixth-year medical student, UEM, Maringá, PR, Brazil.
* Study performed at the Angiology and Vascular Surgery Course
of the Medical School at Universidade Estadual de Maringá (UEM),
Maringá, PR, Brazil.
Correspondence:
Amélia Cristina Seidel
Rua Dr. Gerardo Braga, 118
CEP 87050-610 - Maringá, PR, Brazil
Phone: +55 44 269.1521
Fax: +55 44 225.0999
E-mail: seidel@wnet.com.br
ABSTRACT
Objective:
To gauge the temperature of the 75% glucose, which is used as a
sclerosing agent in the cryosclerotherapy.
Method: With the use of a T-type Thermocouple device, several
measurements of the temperature were taken from 12 samples of glucose,
considering different sites for gauging: inside the cryosyringe
cooled down with carbon dioxide snow, two sites inside the syringe
that contained the sclerosant, and in the glucose which leaked out
of the syringe and the needle. Measurements were carried out in
1, 10, 20 and 30 minutes.
Results: In the 75% glucose samples inside the base of the
syringe of the set used for cryosclerotherapy, the temperature was
-40 ºC. However, there was formation of crystals in this site, which
avoided its use. The temperature of the 75% glucose leaking out
of the needle varied from -3 ºC to -5 ºC.
Conclusion: The temperature of the 75% glucose used in the
cryosclerotherapy is approximately -4 ºC.
Key-words:
lymphedema, aggression, lower extremity.
J
Vasc Br 2005;4(2):155-60
It can
be found in the literature1 that the intravascular
sclerotherapy of varicose veins has been performed since 1840. However,
it was only after the introduction of the hypodermic syringe and the
discovery of new sclerosing agents that the procedure could be considered
a viable form of treatment for telangiectatic or varicose veins.
The ideal
sclerosing agent should be specific for telangiectasias, painless on
injection, and free from complications, causing as much endothelial
reaction as possible.2
In the
conventional sclerosis, results are slow and several sessions are needed
for certain patients in order to finally obtain the expected results,
which may vary according to the physician and depend on personal ability.
To improve the chemical effect of the sclerosing agent, Sánchez3
added the physical effect, reducing the temperature of the agent used
and creating a greater endothelial lesion without increasing the risks.4
When the
cryosclerotherapy started being used, some substances were studied as
sclerosing agents, which were treated with carbon dioxide so that their
temperature of -40 °C would determine a thermal burn in the vein walls.
The aim
of this study was to gauge the temperature of the 75% glucose, which
can also be used in the cryosclerotherapy, once there are no reports
in the literature about this sclerosing agent.
METHOD
To gauge
the temperature of the 75% glucose used for cryosclerotherapy, we used
a t-type thermocouple,5 which has a measuring
range between -270 and 400 °C and margin of error of ± 0.75%.
Nine temperature
measurements were performed in 12 glucose samples, in an 18-day interval,
considering the following measurement sites (Figure 1):
 Figure
1 - Sites where the temperatures were measured.
a) Area 1: inside the capsule immediately after cooling down
with carbon dioxide snow.
b) Area 2: temperature of the glucose inside the base of the
syringe inserted in the capsule.
c) Area 3: temperature of the glucose at the base of the syringe.
d) Area 4: temperature of the glucose which leaked out of the
needle.
e) Area 5: room temperature.
f) Area 6: temperature of the gel which leaked out of the syringe
without needle.
Using
the t-type thermocouple, a simple circuit was made connecting the copper
and constantan wires to a multimeter set at 200 mV, forming the measurement
junction. The wire of the reference junction is set at 0 °C, and it
is not necessary to compensate the room temperature (Figure 2). The
value found was equivalent to values of a table, corresponding to the
temperature obtained.
Figure
2 - Schematic representation of the t-type thermocouple.
Room temperature
was initially measured (area 5). Afterward, the capsule attached to
a carbon dioxide tank was cooled down with carbon dioxide snow and the
temperature inside it was measured with the t-type thermocouple sensor
placed inside the capsule (area 1).
The syringe
containing 3 ml of 75% glucose was placed in the capsule and once again
exposed to the carbon dioxide snow until the formation of crystals in
its base. This was the glucose cooling criterion to start the cryosclerotherapy,
and its temperature was measured at this moment.
Removing
the embolus and without placing the needle in the syringe with the glucose,
the t-type thermocouple sensor was placed inside it, and the temperature
was measured in its base (area 2) and in the other extremity (area 3).
After the
embolus was placed, a slight pressure was made so that the glucose gel
could come out, and another measurement was made (area 6). The last
measurement performed was of the glucose which leaked out of the needle
tip already attached to the syringe (area 4).
While these
measurements were being performed, the syringe was kept inside the capsule,
and time did not exceed 1 minute. After these procedures, the set of
the syringe with the glucose and the capsule remained in the room. After
10, 20, 30 minutes, other measurements of temperature were made in areas
2, 3, and 4.
RESULTS
Results
showed that the temperature of the 75% glucose inside the base of the
syringe of the set used for cryosclerotherapy was -40 ºC. However, there
was formation of crystals in this site, which avoided its use. The temperature
of the 75% glucose leaking out of the needle varied from -3 ºC to -5
ºC (Tables 1 to 4 and Figures 3 to 6).
Figure
3 - Graphic representation of temperature values of the 75% glucose
obtained in different areas of each sample in the first minute.
Figure
4 - Graphic representation of temperature values of the 75% glucose
obtained in different areas of each sample after 10 minutes.
Figure
5 - Graphic representation of temperature values of the 75% glucose
obtained in different areas of each sample after 20 minutes.
Figure
6 - Graphic representation of temperature values of the 75% glucose
obtained in different areas of each sample after 30 minutes.
Table
1 - Temperature values of the 75% glucose obtained in different
areas of each sample in the first minute
 |
Areas
|
Samples |
| |
1 |
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12 |
|
|
| |
Temperature |
|
| Area
1 |
-40
|
-38
|
-38
|
-38
|
-40
|
-38
|
-38
|
-38
|
-38
|
-38
|
-38
|
-40 |
| Area
2 |
-38
|
-27
|
-36
|
-36
|
-36
|
-36
|
-33
|
-36
|
-36
|
-36
|
-36
|
-36 |
| Area
3 |
-36
|
-30
|
-33 |
-36
|
-33
|
-33
|
-33
|
-33
|
-36
|
-33
|
-33
|
-33 |
| Area
4 |
-3
|
-3
|
-5
|
-5 |
-5
|
-3
|
-5
|
-5
|
-5
|
-5
|
-5
|
-3 |
| Area
5 |
23
|
22
|
21 |
23
|
21
|
21
|
27
|
23
|
23
|
23
|
23
|
23 |
| Area
6 |
-33
|
-24
|
-24
|
-23
|
-24
|
-27
|
-27
|
-23
|
-23
|
-23
|
-27
|
-21 |
|
Table
2 - Temperature values of the 75% glucose obtained in different
areas of each sample after 10 minutes
|
Areas
|
Samples |
|
1 |
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12 |
|
|
| |
Temperature |
|
| Area
2 |
-33
|
-27
|
-31
|
-31
|
-32
|
-33
|
-33
|
-32 |
-31
|
-32
|
-33
|
-33 |
| Area
3 |
-32
|
-27
|
-31
|
-31
|
-32
|
-33
|
-33
|
-32
|
-31
|
-31
|
-32
|
-33 |
| Area
4 |
-3
|
-3
|
-3
|
-4
|
-5 |
-3
|
-4
|
-4
|
-3
|
-3
|
-3
|
-5 |
|
Table
3 - Temperature values of the 75% glucose obtained in different
areas of each sample after 20 minutes
|
| Areas
|
Samples |
|
1 |
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12 |
|
|
| |
Temperature |
|
| Area
2 |
-27
|
-26
|
-27
|
-27
|
-28
|
-27 |
-28
|
-28 |
-27
|
-27
|
-28
|
-26 |
| Area
3 |
-27
|
-26
|
-27
|
-27
|
-28
|
-27
|
-28
|
-28
|
-27
|
-27
|
-28
|
-26 |
| Area
4 |
-3
|
-3
|
-3
|
-3
|
-4
|
-3
|
-3
|
-3
|
-3
|
-3
|
-3
|
-3 |
|
Table
4 - Temperature values of the 75% glucose obtained in different areas
of each sample after 30 minutes
|
| Areas
|
Samples |
| |
1 |
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11 |
12 |
|
|
| |
Temperature |
|
| Area
2 |
-23
|
-22 |
-24 |
-24 |
-24 |
-24
|
-23
|
-23 |
-22
|
-22
|
-23
|
-22 |
| Area
3 |
-23
|
-22
|
-24
|
-24 |
-24
|
-24
|
-23
|
-23 |
-22 |
-22
|
-23
|
-22 |
| Area
4 |
-3
|
-2
|
-3
|
-3 |
-3 |
-3 |
-3
|
-3
|
-3
|
-3
|
-3
|
-3 |
|
DISCUSSION
With the
introduction of the cryosclerotherapy technique, substances already
used for the conventional sclerotherapy were studied in relation to
their freezing point (Table 5). Thus, Sánchez6
suggested its use at a -40 °C temperature. The sclerosing agent in the
needle, kept at room temperature and in contact with the physician's
hand, suffers a temperature alteration. Because of this, the author
indicated the use of the capsule, which is a double syringe, whose internal
compartment receives the sclerosing agent, while in the external compartment
there is a device for keeping low temperatures. He used the carbon dioxide
snow as a cooling agent, due to its excellent thermal qualities and
advantages: 1) maintains the sclerosing agent at temperatures lower
than -40 °C during 25 minutes, a period of time enough to inject 1 ml
of sclerosing agent in thin networks of telangiectasias; 2) eliminates
the need of having a refrigerator that reaches low temperatures; 3)
has only one CO2 balloon for the production of carbon dioxide snow,
which adapts itself to the capsule; 4) simplifies the preparation technique
for the cryosyringe; 5) less time to obtain the sclerosing agent temperature
lower than -40 °C. It only takes 3 minutes, against 80 minutes, is case
the refrigerator is used.
Table
5 - Freezing point of studied substances
|
| Substance
|
Freezing
point |
|
| Ethanol
|
-114.1
°C |
| Glycerin
66.7% H2O 33.3% |
-40
°C |
| Propylene
glycol |
-60
°C |
| Aetoxisclerol
|
-20
°C |
|
Miyake2
cited that the hypertonic glucose, introduced by Kausch in 1917 and
classified as an osmotic solution for causing dehydration of endothelial
cells with destruction of the endothelium1,
is efficient, has a low cost, and practically does not present severe
complications, such as allergies, systemic reactions, and necrosis.2
Concerning
the 75% glucose as an sclerosing agent for cryosclerotherapy, it can
be said that it stays in contact with the endothelium for a longer period
of time, increasing both the destructive action of the cold and the
hyperosmolar effect, due to the increase in its viscosity and vasoconstriction
obtained though the cold. Vasoconstriction reduces bleeding and the
occurrence of ecchymosis and, therefore, there is a lower level of pigmentation.
There would also be a reduction in the pain caused by the analgesic
action of the cold.4
This research
was performed using the same cryosclerotherapy technique described in
the literature, with the cryosyringe and the carbon dioxide snow, but
using the 75% glucose as a sclerosing agent. The temperature was measured
in several sites, as described in the method, as well as in different
times, simulating a sclerotherapy session.
In the
results, it can be observed that, despite the temperature of the 75%
glucose inside the base of the syringe being -40 °C, the temperature
which leaked out of the needle ranged from -3 °C to -5 °C, much different
from the temperature reported in the literature of other substances
used as sclerosing agents. The difference in the temperatures obtained
in times 10, 20, and 30 minutes was small compared to the first measurement,
and did not present a significant variation. It can thus be concluded
that the 75% glucose is actually used at approximately -4 °C for cryosclerotherapy.
REFERENCES
1.
Goldman MP. Escleroterapia. Tratamento das veias varicosas e telangiectasias
dos membros inferiores. 1ª ed. Rio de Janeiro: Interlivros; 1994.
2.
Miyake H, Hiroshi K. Tratamento das microvarizes e telangiectasias.
In: Maffei FHA. Doenças vasculares periféricas. 3ª
ed. Rio de Janeiro: Medsi; 2002. p. 1563-80.
3.
Ripoll-Sánchez M. Presentación de uma técnica:
crioesclerosis líquida. Rev Soc Esp Med Estet. 1995;39:19-24.
4.
Francischelli Neto M. Estudo comparativo entre a escleroterapia convencional
e a escleroterapia em baixa temperatura no tratamento das telangiectasias
dos membros inferiores [dissertação]. Campinas: Faculdade
de Ciências Médicas da Universidade Estadual de Campinas;
2002.
5. Borchardt I. Termometria, termoelétrica, termopar.
2ª ed. Porto Alegre: Sagra Livraria Editora; 1979.
6.
Ripoll-Sánchez M. Crioesclerose líquida. Rev Soc Bras
Med Estet 2001;12:53-7.
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