1A Andriessen PhD, 2IKY Wong, PhD, 3M Abel PhD 1Andriessen Consultants & UMC St. Radboud, The Netherlands. anneke.a@tiscali.nl 2Head of School, School of Nursing, Hong Kong Sanatorium & Hospital, HK 3Head of Medical & Regulatory Affairs, Lohman & Rauscher, Germany

1. INTERFACE PRESSUREAND STATIC
STIFFNESSINDEXOF FOUR
COMPRESSIONSYSTEMS
1A AndriessenPhD, 2IKY Wong, PhD, 3M Abel PhD
1Andriessen Consultants & UMC St. Radboud, The Netherlands. anneke.a@tiscali.nl
2Head of School, School of Nursing, Hong Kong Sanatorium & Hospital, HK
3Head of Medical & Regulatory Affairs, Lohman & Rauscher, Germany
IKY Wong, MBL Man, OSH Chan, SF Chi, M Abel, A Andriessen.JWC. Vol 21; no 4; April 2012.
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2. Methods
Inclusion:
• Healthy male or female ambulant patients of >
18 years;
• Having healthy legs ABI >0.8 or a normal pulse
volume recording;
• Patients had the ability to understand and
communicate in Cantonese.
Exclusion:
• Allergy against one of the used materials;
• Arterial occlusive disease (ABPI less than 0.8);
• Ulcers on the lower limb;
• Lower limb oedema;
• Known history of dermatological problems such as
eczema or cellulitis.
• The experimental study aimed to compare Interface Pressure (IP) and Static Stiffness
Index (SSI) of four different compression systems that are currently in use for venous
leg ulcer and lymphedema treatment of the lower limbs.
• Experimental study (N=52); Recruitment was at random; Patients gave informed
consent; Local ethical committee aproval was obtained (Hong Kong Sanatorium and
Hospital) .
IKY Wong, MBL Man, OSH Chan, SF Chi, M Abel, A Andriessen. JWC. Vol 21; no 4; April 2012.
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3. Working definitions
• Interface pressure (IP): Pressure exerted on the limb by
compression materials, measured as sub-bandage pressure
• Stiffness: The degree of stiffness is demonstrated by the pressure
increase per cm. increase in leg circumference
• Static stiffness index (SSI): The pressure difference between
pressure measured at B1, in supine and in the standing position
• SSI > 10: The compression system has high stiffness and is
considered to be inelastic
• SSI < 10: The system has low stiffness and is considered to be
elastic
Mosti, G., Mattaliano, V., Partsch, H. Phlebology. 2008; 23: 6, 287–294.
Partsch, H. et al. Eur J Vasc Endovasc Surg. 2005; 30: 4, 415–421.
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4. N=52 healthy subjects
LSB SSB VSB
IP every 15 minutes
for 4 hours in supine,
standing, siting,
walking
IP every 15 minutes
for 4 hours in supine,
standing, siting,
walking
IP every 15 minutes
for 4 hours in supine,
standing, siting,
walking
Analyzed in the ITT analysis N= 52
Flow chart
CS
IP every 15 minutes
for 4 hours in supine,
standing, siting,
walking
IKY Wong, MBL Man, OSH Chan, SF Chi, M Abel, A Andriessen. JWC. Vol 21; no 4; April 2012.
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5. IP measurements
• Portable Kikuhime (Harada Corp.) was used for IP measurements
• Repeatability: Error: >0.3mmHg, linear response: 5–50mmHg
• The sensor (3cm ø) was placed at point B1: located at the medial
aspect of the leg, where the gastrocnemius tendon turns in its
muscular part.
IKY Wong, MBL Man, OSH Chan, SF Chi, M Abel, A Andriessen. JWC. Vol 21; no 4; April 2012.
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6. Parameters & analysis
• Primary outcome measure:
Interface pressure measured in supine, sitting, standing and walking
and Static Stiffness Index
• ITT analysis:
Parametric or non-parametric tests (SPSS:IBM Corp.)
Mann-Whitney U or paired t-test were used for intragroup and per
group comparisons of the IP measured in the different positions and over
time
IKY Wong, MBL Man, OSH Chan, SF Chi, M Abel, A Andriessen. JWC. Vol 21; no 4; April 2012.
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7. Results: IP in supine
p=0.05
N=52
mmHg SSB LSB VSB CS Paired T-test
Mean (±SD) 40.68 (±5.01) 48.12 (±4.57) 48.96 (±3.99) 37.82 (±0.58) SSB, LSB, VSB vs. CS: p = 0.05
Median (range) 41 (39-60) 50 (44-59) 51 (46-60) 40 (39-41)
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8. Results: IP while walking
mmHg SSB LSB VSB CS Paired T-test
Mean (±SD) 56.11 (±5.01) 69.59 (±6.24) 66.21 (±4.02) 40.04 (±1.77) SSB, LSB, VSB vs. CS: p = 0.05
Median (range) 57 (52-80) 73 (64-90) 69 (64-80) 42 (40-45)
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9. Results: SSI
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10. Conclusions
• All four compression systems were able to sustain an IP at
proposed effective therapeutic levels
• IP and SSI information may enable clinicians to predict the
frequency of bandage application, supporting an adequate
and safe choice of bandage system
• A tubular compression systems may increase the patients’
participation in, and compliance with, compression therapy,
thereby saving on costs and nursing time
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Thankyouforyourattention