Impact of Foam Dressings with small Pores and narrow Pore
Distribution on the Uptake of highly Viscous Exudate
Marco Schubert , Sascha Casu
1
1
BSN medical GmbH (Hamburg, Germany)
1
Introduction and Aim
Foam products are known for good fluid handling capacities often measured with Sol A (salt solution). Application of Sol A cannot predict how
foam products will behave in real conditions since the absence of proteins which tend to increase viscosity over time and leading to encrustations
in and around the foams. This test aims on showing the impact of foam structure on the ability to handle highly viscous fluid shown in artificial
wound model.
Method
Foam dressings were put on a plate (37°C), through a hole in the middle an Albumin/Pektin test solution was fed into the products (size
10 x10cm, 5mm foam) at 2 ml/h over approx. 16 hours. A box (MVTR) on top filled with silica gel catches the evaporated amount of water.
Determination of gravimetric difference of the dressings and the MVTR box before and after measurement and subtraction from the initial amount
gets the absorption, MVTR and residue in the system. After measurement photos of foam were taken to examine the uptake of fluid in the foam.
Results
It was found that foams with small pores separate the solid content from the water which leads to encrustations on the model’s wound surface.
Exemplary comparison of products with small, medium and great pores.
Conclusion
Fluids with high solid content like exudate with cell debris, proteins and blood hardeners get filtered by small pored dressings so that heavy parts
would reside on the patient’s wound surface.
Setting of Measurement
• 16 hours of testing
• Products of 5 mm
• N= 6
• 37°C
• 2 ml/hr
• Sol A, Albumin, Pektin, 1.1 g/ml
• Images taken after measurement
• Calculation of gravimetric
difference in dressing, MVTR Box
and fed solution
Housing
MVTR Box
Dressing
• High viscous fluid is fully
transported vertically
• Wound bed area is nearly free of
fluid but not dry
• Area around the wound bed is dry
Figure 1:
Product A with big pores on simulated woundbed from top after measurement
Figure 2:
Simulated woundbed after measurement
Figure 3:
Product A with big pores from wound contact side after measurement
Figure 4:
Microscopy of a slice of Product A at 1.6X magnification
Simulated
wound bed
Salt solution
+ Albumin (Protein)
+ Pektin (Hardener)
• High viscous fluid is not fully
transported vertically
• Wound bed area shows residues
• Area around the wound bed is wet
• High viscous fluid is not
transported
vertically into the foam
• Wound bed area shows a lot of
residues due to blocking
• Area around the wound bed is
very wet
Figure 5:
Product D with medium pores on simulated woundbed from top after measurement
Figure 6:
Simulated woundbed after measurement
Figure 9:
Product I with small pores on simulated woundbed from top after measurement
Figure 10:
Simulated woundbed after measurement
Figure 7:
Product D with medium pores from wound contact side after measurement
Figure 8:
Microscopy of a slice of Product D at 1.6X magnification
Figure 11:
Product I with small pores from wound contact side after measurement
Figure 12:
Microscopy of a slice of Product I at 1.6X magnification
Fluid handling of commercially available products with small, medium and big pores
100%
Big
Pores
90%
80%
70%
60%
Medium
Pores
50%
40%
30%
Small
Pores
20%
10%
Residue (%)
MVTR (%)
Absorption (%)
A: Cutimed Siltec, B: Mepilex, C: Perma Foam, D: Allevyn non adhesive, E: Allevyn Gentle Border,
F: Biatain Silicone, G: Askina Dressil, H: Draco Foam, I: Urgocell Contact
I
H
G
F
E
D
C
B
A
0%
EWMA Conference 2013,
15-17 May, Copenhagen, Denmark