The Static Stiffness Index: an important parameter to characterise compression therapy in vivo

The compression pressure, which corresponds to the dosage of compression therapy, has been widely neglected up to now, not only concerning scientific literature, but also in clinical practice. It is evident that compression pressures in the upright position and during walking are clinically more relevant than just the resting pressure. The Static Stiffness Index (SSI), which is the difference between standing and resting pressure, is a valuable parameter characterising the efficacy of a specific compression product to narrow/occlude the venous lumen. This is a prerequisite for reducing venous reflux and exerting a massaging effect necessary to improve the venous pumping function during movement. This article provides an overview of the recent literature on the SSI, which supports the recommendations of the International Compression Club. In addition, it aims to provide an insight on the importance of the SSI in daily practice, as an educational tool as well as in defining the properties of applied compression therapy in clinical research.

The treatment of venous leg ulcers with a specifically designed compression stocking kit

Traditionally, venous leg ulcers are treated with firm nonelastic bandages. Medical compression stockings are not the first choice although comparative studies found them equally effective or superior to bandages. Patients, methods: We report on a multi-center randomized trial with 60 patients treated with either short stretch multi-layer bandages or a two-stocking system (Sigvaris® Ulcer X® kit). Three patients have been excluded because their ankle movement was restricted to the extent that they could not put on the stockings and 1 patient withdrew consent. Patient characteristics and ulcer features were evenly distributed. The proportion of ulcers healed within 4 months and the time to completion of healing were recorded. Subjective appraisal was assessed with a validated questionnaire. Results: Complete wound closure was achieved in 70.0% (21 of 30) with bandages and in 96.2% (25 of 26) with the ulcer X kit (p = 0.011). Ulcers with a diameter of up to about 4cm healed twice as rapidly, the larger ones as fast with the stocking kit as with bandages. The sum of problems encountered with bandages was significantly greater than that observed with the stocking kit (p < 0.0001). Pain at night and in the morning was absent with stockings but reported by 40% and 20% in the bandage group, respectively. The cardinal features associated with delayed or absent healing were ulcer size and pain. Conclusions: Common venous ulcers can readily be treated with the ulcer X compression kit provided the ankle movement allow its painless donning. Bandages, even when applied by the most experienced staff are less effective and cause more problems.

A Review of Microvascular Measurements in Wound Healing

The microcirculatory evaluation in patients affected by arteriopathic or venous ulcers is usually carried out using laser Doppler flowmetry, transcutaneous oxygen (transcutaneous pressure of oxygen, TcPO2), and carbon dioxide (transcutaneous pressure of carbon dioxide, TcPCO2) measurements and capillaroscopy. These techniques provide significant pathophysiologic and prognostic information. TcPO2 and TcPCO2 diagnose and classify the extent of arterial disease in the leg ulcers caused by arterial disease; the prognostic value is recognized, though doubts about its prognostic potential exist in the case of leg ulcer. Laser Doppler flowmetry is able to identify the first functional impairment in the early stages of the arterial disease and in the complicated venous insufficiency. Capillaroscopy gives us morphological and quantitative parameters of the capillary bed that is damaged in arteriopathic and venous ulcers; nevertheless, it does not provide us with definite prognostic indexes. Combining the 3 methods may contribute to yield objective measures in the clinical management of lower extremity ulcers.

Adjustable Velcro Compression Devices are More Effective than Inelastic Bandages in Reducing Venous Edema in the Initial Treatment Phase: A Randomized Controlled Trial

OBJECTIVE/BACKGROUND

The objective of this study was to compare the efficacy and comfort of inelastic bandages (IBs) and adjustable Velcro compression devices (AVCDs) in reducing venous leg edema in the initial treatment phase.

METHODS

Forty legs from 36 patients with untreated venous edema (C3EpsAsdPr) were randomized to two groups. Patients in the first group received IBs (n = 20) and those in the second AVCDs (n = 20). Both compression devices were left on the leg day and night, and were renewed after 1 day. Patients in the AVCD group were asked to re-adjust the device as needed when it felt loose. Leg volume was calculated using the truncated cone formula at baseline (T0), after 1 day (T1) and after 7 days (T7). The interface pressure of the two compression devices was measured by an air filled probe, and the static stiffness index calculated after applying compression at T0 and T1, and just before removal of compression on T1 and T7. Patient comfort with regard to the two compression systems was assessed by grading signs and symptoms using a visual analog scale.

RESULTS

At T1, the median percent volume reduction was 13% for the IB group versus 19% for the AVCD group; at T7 it was 19% versus 26%, respectively (p < .001). The pressure of the IBs was significantly higher compared with the AVCDs at T0 (63 vs. 43 mmHg) but dropped by > 50% over time, while it remained unchanged with AVCDs owing to the periodic readjustment by the patient. Comfort was reported to be similar with the two compression devices.

CONCLUSION

Re-adjustable AVCDs with a resting pressure of around 40 mmHg are more effective in reducing chronic venous edema than IBs with a resting pressure of around 60 mmHg. AVCDs are effective and well tolerated, not only during maintenance therapy, but also in the initial decongestive treatment phase of patients with venous leg edema.

Comparative study of two antimicrobial dressings in infected leg ulcers: a pilot study

OBJECTIVE

The aim of the study was to compare the efficacy of a microorganism-binding (MB) dressing with a silver-containing hydrofiber (SCH) dressing in controlling the bacterial loads of heavily colonised or locally infected chronic venous leg ulcers, before surgical management with homologous skin grafts.

METHOD

A randomised comparative single centre study recruited patients presenting with hard-to-heal critically colonised or locally infected leg ulcers, who could be treated with skin grafting. Inclusion criteria included; ulcers of vascular aetiology, over 18 years old, a wound duration ≥6 months and ankle brachial index (ABPI) >0.6. Patients were randomly assigned to treatment with SCH dressings (Aquacel Ag) or MB dressing (Cutimed Sorbact). Dressings were changed daily over a four-day observation period, after which they were taken for a skin grafting procedure. Swab samples from ulcer beds were taken in order to quantify the bacterial load at inclusion (D0) and at the end of the observation period day 4 (D4). No antibiotics were administered before or during the evaluation period.

RESULTS

Both groups (n=20 SCH, n=20 MB) were similar in gender, age, pathophysiology (both had 15 patients with venous leg ulcers and 5 with arterial leg ulcers), ulcer surface, ulcer duration, treatment-related pain and initial bacterial load. Analysing bacterial load variation showed a significant reduction of bacterial burden at D4 in both groups. In the SCH group, we found an average bacterial load reduction of 41.6%, with an average reduction of 73.1% in the MB group (p< 0.00001). No serious adverse events were reported.

CONCLUSION

Our evaluation confirmed that MB and SCH dressings are effective in reducing the bacterial burden in critically colonised or locally infected chronic leg ulcers, without inducing adverse events, with MB dressings significantly more effective.

DECLARATION OF INTEREST

There were no external sources of funding for this study. The authors have no conflicts of interest to declare.

Sport socks do not enhance calf muscle pump function but inelastic wraps do

AIM

Aim of the study was to measure the effect of elastic and inelastic compression on calf muscle pump function in healthy male athletes.

METHODS

This was an experimental study which included 21 healthy male athletes. The ejection fraction (EF) of the venous calf pump was measured comparing the effects of a variety of compression materials: 1) sport compression stockings; 2) light zinc paste bandages; 3) sport compression stockings with additional Velcro® wraps over the calf. The influence of sport stocking and wraps on the venous calibre at the largest calf circumference in the lying and standing position was investigated using MRI.

RESULTS

Inelastic compression exerting a median pressure in the standing position of 37.5 mmHg (zinc paste) and 48 mmHg (loosely applied straps over a sport stocking) achieved a significant increase of EF up to 100%. Sport stockings alone with a standing pressure of 19-24 mmHg did not show a significant change of EF. MRI demonstrated some venous narrowing in the lying but not in the standing position. By wrapping inelastic straps over the stocking an emptying of the veins in the lying and a considerable narrowing in the standing position could be observed.

CONCLUSION

Venous calf pump function in athletes is not influenced by elastic sport stockings, but inelastic wraps either alone or applied over sport stockings lead to a significant enhancement.

Improvement of venous pumping function by double progressive compression stockings: higher pressure over the calf is more important than a graduated pressure profile

BACKGROUND

Previous studies have shown that so-called progressive elastic compression stockings (PECS) with a negative pressure gradient have a more pronounced effect on venous pump function than conventional, graduated stockings. The aim of this study was to investigate the effect of higher graduated and non-graduated pressures on the venous calf pump in patients with venous disease.

METHODS

The ejection fraction (EF) of the calf pump was measured by plethysmography under a standardized walking test in 20 patients suffering from chronic venous disease (CEAP C2-C5) without compression, (a) with one and (b) two PECS on top of each other, and (c) with one additional conventional stocking covering only the gaiter area to achieve a graduated high pressure profile. Interface pressure was measured in the gaiter area and on the calf.

RESULTS

A significant improvement of EF compared with baseline was found with all three compression modalities. The two superimposed PECS, providing median pressures of 33 mmHg in the gaiter area and 46 mmHg at calf level, increased EF significantly up into the normal range. Increasing the gaiter pressure to 56 mmHg without changing the calf pressure did not result in further improvement.

CONCLUSIONS

Two PECS applied on top of each other lead to a maximal improvement of the venous pump function, which cannot be further improved by increasing the pressure in the gaiter area thereby restoring a graduated pressure profile.

Wound care in venous ulcers

Wound dressings: ulcer dressings should create and maintain a moist environment on the ulcer surface. It has been shown that in an ulcer with a hard crust and desiccated bed, the healing process is significantly slowed and sometimes completely blocked so favouring infection, inflammation and pain. In contrast a moist environment promotes autolytic debridement, angiogenesis and the more rapid formation of granulation tissue, favours keratinocytes migration and accelerates healing of wounds. Apart from these common characteristics, wound dressings are completely different in other aspects and must be used according to the ulcer stage. In necrotic ulcers, autolytic debridement by means of hydrogel and hydrocolloids or with enzymatic paste is preferred. In case of largely exuding wounds alginate or hydrofibre are indicated. When bleeding occurs alginate is indicated due to its haemostatic power. Where ulcers are covered by granulation tissue, polyurethane foams are preferred. When infection coexists antiseptics are necessary: dressing containing silver or iodine with large antibacterial spectrum have proved to be very effective. In the epithelization stage polyurethane films or membranes, thin hydrocolloids or collagen based dressings are very useful to favour advancement of the healing wound edge. Despite these considerations, a Cochrane review failed to find advantages for any dressing type compared with low-adherent dressings applied beneath compression. Surgical debridement and grafting of wounds, negative wound pressure treatment: surgical and hydrosurgical debridement are indicated in large, necrotic and infected wounds as these treatments are able to get rid of necrotic, infected tissue very quickly in a single surgical session, thereby significantly accelerating wound bed preparation and healing time. Negative wound pressure treatment creating a negative pressure on ulcer bed is able to favour granulation tissue and shorten healing time. In case of hard-to-heal leg ulcers such as large, deep, infected and long-lasting venous ulcers, sharp debridement and skin grafting may favour and shorten ulcer healing.

Bandages or double stockings for the initial therapy of venous oedema? A randomized, controlled pilot study

OBJECTIVE/BACKGROUND

Treatment for leg oedema conventionally starts with compression bandaging followed by elastic stockings once swelling is reduced. The aim was to investigate if a kit consisting of a liner and outer stocking, each exerting 20 mmHg of pressure, would be equally effective in achieving and maintaining volume reduction compared with short-stretch bandaging (2 weeks) followed by a class II (23-33 mmHg) stocking (2 weeks).

METHODS

Forty legs (28 patients) with chronic venous oedema were randomised to either short-stretch bandages applied weekly for 2 weeks, followed by an elastic stocking for 2 weeks (group A) or a light stocking ("liner") for 1 week followed by superimposing a second stocking for 3 weeks (group B). Interface pressures and leg volumes were measured weekly.

RESULTS

Despite differences in the pressure (median ± interquartile range) applied (bandage: 67 mmHg [55.7-73.0] vs. liner 24.5 mmHg [21.2-26.5]) volume reduction after 1 week was equal (12.8% [8.7-16.5] and 13.0% [10.4-20.6]). After 2 weeks (group A: 17.8% [10.6-20.0] vs. group B 16.2% [13.0-25.4]) and 4 weeks (group A: 17.3% [9.6-22.8] vs. group B: 17.0% [13.1-24.1]) volume reductions remained identical.

CONCLUSIONS

The initial improvement in leg volume (1 week) was independent of the pressure applied and the reduction was maintained by superimposing a second stocking. This offers a simple alternative for managing leg oedema with reduced staffing costs.

Post-treatment compression: duration and techniques

BACKGROUND

Compression treatments used the following intervention for varicose veins range from no compression, to elastic stockings and compression bandaging. There is no consensus on the strength or duration of compression which should be applied following a particular treatment. The author reviews the evidence that has led him to reach his own viewpoint on this subject.

SUMMARY

Compression stockings are often prescribed after treatment of varicose veins, but these in general exert a much lower pressure in the thigh compared with firm inelastic compression bandages. It has been shown by objective investigation that it takes a pressure of 10-15 mmHg in the supine position and 40-50 mmHg in the standing position to occlude a superficial vein in the thigh. The author has published a study in which three groups of patients were studied following varicose vein surgery. One group received a strong medical compression stocking, the second group an inelastic bandaging system which achieved 63 mmHg compression in the standing position and an eccentric compression system which achieved 98 mmHg in the standing position. Adverse events after surgery were most frequent in the stocking group with fewer in the inelastic compression bandage group and fewest in the eccentric compression group. A further study has been published by another author in which elastic compression has been compared with eccentric compression following endovenous laser ablation of the saphenous vein. Eccentric compression reduced postoperative pain. Unfortunately, very little data are available to indicate the period for which compression should be applied following varicose vein treatment.

CONCLUSIONS

In comparison to compression treatments following varicose vein surgery where the actual level of compression has been measured, higher levels of compression are more effective than lower levels in moderating postoperative pain and complications. Strong compression can be achieved by inelastic bandaging or by eccentric compression systems. Far fewer data are available to indicate the duration for which postoperative compression is required.

Chronic edema of the lower extremities: international consensus recommendations for compression therapy clinical research trials

Chronic edema is a multifactorial condition affecting patients with various diseases. Although the pathophysiology of edema varies, compression therapy is a basic tenant of treatment, vital to reducing swelling. Clinical trials are disparate or lacking regarding specific protocols and application recommendations for compression materials and methodology to enable optimal efficacy. Compression therapy is a basic treatment modality for chronic leg edema; however, the evidence base for the optimal application, duration and intensity of compression therapy is lacking. The aim of this document was to present the proceedings of a day-long international expert consensus group meeting that examined the current state of the science for the use of compression therapy in chronic edema. An expert consensus group met in Brighton, UK, in March 2010 to examine the current state of the science for compression therapy in chronic edema of the lower extremities. Panel discussions and open space discussions examined the current literature, clinical practice patterns, common materials and emerging technologies for the management of chronic edema. This document outlines a proposed clinical research agenda focusing on compression therapy in chronic edema. Future trials comparing different compression devices, materials, pressures and parameters for application are needed to enhance the evidence base for optimal chronic oedema management. Important outcomes measures and methods of pressure and oedema quantification are outlined. Future trials are encouraged to optimize compression therapy in chronic edema of the lower extremities.

High compression pressure over the calf is more effective than graduated compression in enhancing venous pump function

BACKGROUND

Graduated compression is routinely employed as standard therapy for chronic venous insufficiency.

AIM

The study aims to compare the haemodynamic efficiency of a multi-component graduated compression bandage (GCB) versus a negative graduated compression bandage (NGCB) applied with higher pressure over the calf.

METHODS

In 20 patients, all affected by greater saphenous vein (GSV) incompetence and candidates for surgery (Clinical, etiologic, anatomic and pathophysiologic data, CEAP C2-C5), the ejection fraction of the venous calf pump was measured using a plethysmographic method during a standardised walking test without compression, with GCB and NGCB, all composed of the same short-stretch material. Sub-bandage pressures were measured simultaneously over the distal leg and over the calf.

RESULTS

NGCBs with median pressures higher at the calf (62 mmHg) than at the distal leg (50 mmHg) achieved a significantly higher increase of ejection fraction (median +157%) compared with GCB, (+115%) with a distal pressure of 54 mmHg and a calf pressure of 28 mmHg (P < 0.001).

CONCLUSIONS

Patients with severe venous incompetence have a greater haemodynamic benefit from NGCB, especially during standing and walking, than from GCB.

Dose finding for an optimal compression pressure to reduce chronic edema of the extremities

AIM

The optimal pressure to reduce chronic extremity swelling is still a matter of debate. The aim of this paper was to measure volume reduction of a swollen extremity depending on the amount of pressure exerted by compression stockings and inelastic bandages.

METHODS

Thirty-six patients with unilateral breast cancer related arm lymphedema were investigated in a lymph clinic in the Netherlands, 42 legs with chronic edema of the lower extremities were examined in a phlebological centre in Italy. The arm-patients were randomized to receive inelastic arm bandages with a pressure between 20-30 mmHg or 44-68 mmHg. The leg patients were either treated with compression stockings (23-32 mmHg) or with inelastic bandages (pressure 53-88 mmHg). Water-displacement volumetry and measurement of leg circumference was performed before and after compression.

RESULTS

In the arm-patients low pressure after 2 hours achieved a higher degree of volume reduction (-2.3%, 95% CI 1.0-3.6) than high pressure (-1.5%, 95% CI 0.2-2.8) (n.s.). In patients with leg edema compression stockings in the range between 20 and 40 mmHg showed a positive correlation between exerted pressure and volume reduction, bandages applied with an initial resting pressure of more than 60 mm Hg resulted in a decreasing volume reduction.

CONCLUSION

There is obviously an upper limit beyond which further increase of compression pressure seems counterproductive. For inelastic bandages this upper limit is around 30 Hg on the upper and around 50-60 mmHg on the lower extremity.

Compression stockings with moderate pressure are able to reduce chronic leg oedema

Aim

To compare the efficacy of compression stockings and inelastic, high-pressure bandages concerning leg volume reduction in patients with chronic leg oedema.

Material and methods

Forty-two legs of 30 patients with chronic leg oedema caused by venous stasis were randomized to receive a strong inelastic bandage (IB) or an elastic stocking (ES) exerting a pressure of 23–32 mmHg. Changes in leg oedema were assessed after two and seven days by water displacement volumetry, measurements of leg circumferences and of skin thickness by using Duplex ultrasound. Interface pressure was registered under the compression devices for seven days.

Results

There was no significant difference between stockings and bandages, which both produced a significant reduction in leg volume after two days (−9.6% [95% CI 7.5–11.8] by ES and −11.5% [95% CI 9.9–13.2%] by IB) and after seven days (−13.2% [95% CI 10.4–16.2] by ES and −15.6% [95% CI 12.8–18.4] by IB). Bandages showed a more pronounced reduction in leg circumference and in skin thickness in the calf region. The pressure of IB in the lying position fell from initially 63 to 22 mmHg after two days, but only from 33 to 26 mmHg under ES (median values). The optimal pressure range concerning oedema reduction was found between 40 and 60 mmHg, while higher pressures produced by bandages showed a negative correlation with volume reduction.

Conclusions

Compression stockings exerting a pressure of around 30 mmHg are nearly as effective as high-pressure bandages with an initial pressure over 60 mmHg in reducing chronic leg oedema.

Compression stockings with a negative pressure gradient have a more pronounced effect on venous pumping function than graduated elastic compression stockings

OBJECTIVES

To measure the effect on the venous pumping function of a stocking providing a negative pressure gradient with higher pressures over the calf in comparison to a conventional graduated elastic compression stocking (GECS) in patients with advanced venous insufficiency.

DESIGN

Experimental study.

MATERIAL

30 patients with severe superficial chronic venous insufficiency were enrolled. Two elastic stocking designs exerting a pressure at ankle between 15 and 25 mm Hg were compared; a conventional GECS and a stocking exerting a higher pressure over the calf than over the ankle producing a "progressive" increase in compression (PECS).

METHOD

the venous calf pumping function was assessed by measuring the ejection fraction (EF) from the lower leg by a plethysmographic method during a standardised exercise. Interface pressure of the 2 compression devices was simultaneously recorded both at B1 = 12 cm above ankle, C = just above widest part of calf.

RESULTS

The mean increase of EF produced by PECS was +75% (95 CI 48, 7-101,3) compared with +32% (95% CI 16, 8-48,6) with GECS (P < 0.001). There was a significant correlation between EF and the stocking pressure measured at calf level during standing and walking.

CONCLUSION

Stockings exerting a higher pressure on the calf than on the ankle show a greater efficacy in increasing the venous ejection fraction from the leg.

Classification of wounds at risk and their antimicrobial treatment with polihexanide: a practice-oriented expert recommendation

Currently, there are no generally accepted definitions for wounds at risk of infection. In clinical practice, too many chronic wounds are regarded as being at risk of infection, and therefore many topical antimicrobials - in terms of frequency and duration of use - are applied to wounds. Based on expert discussion and current knowledge, a clinical assessment score was developed. The objective of this wounds at risk (W.A.R.) score is to allow decision-making on the indication for the use of antiseptics on the basis of polihexanide. The proposed clinical classification of W.A.R. shall facilitate the decision for wound antisepsis and allow an appropriate general treatment regimen with the focus on the prevention of wound infection. The W.A.R. score is based on a clinically oriented risk assessment using concrete patient circumstances. The indication for the use of antiseptics results from the addition of differently weighted risk causes, for which points are assigned. Antimicrobial treatment is justified in the case of 3 or more points.

Measuring venous pumping function by strain-gauge plethysmography

AIM

Hemodynamic effects of compression devices in patients with venous insufficiency are still under dispute. The aim of this paper was to describe a method which is able to give quantitative results concerning an improvement of the venous pumping function by using compression devices in patients with venous insufficiency.

METHODS

The ejection fraction (EF) of the calf pump can be measured using strain gauge plethysmography proximal to a compression device on the leg and the degree of improvement depending on the exerted pressure and the elastic property of the material can be assessed. Experiments were carried out in 15 normal volunteers and in a total of 68 patients with severe superficial venous incompetence and who were investigated without compression and with various compression devices measuring interface pressure in different body positions.

RESULTS

Examples demonstrating the usefulness of the plethysmographic method are given. The median values of EF were 64.6 (IQR 63.4-68.6) in normal subjects and about half in the venous patients. Statistically significant improvement was achieved using inelastic bandages, resulting in further improvements with increasing pressures between 20 and 60 mmHg. Elastic stockings led only to a moderate improvement of the deficient venous pumping function. Significant correlations were found between EF and standing and walking pressure.

CONCLUSION

The described plethysmographic method is very useful to assess haemodynamic effects of different compression devices in patients with venous insufficiency.

Narrowing of leg veins under compression demonstrated by magnetic resonance imaging (MRI)

AIM

The aim of this paper was to demonstrate the usefulness of magnetic resonance imaging (MRI) for detecting the ability of compression material in narrowing superficial and deep veins in the lower extremity.

METHODS

MRI of the legs was performed in one healthy volunteer and in 11 patients with CEAP C2-C4 without and with different kinds of compression devices. The cross section area of superficial and deep veins was measured by planimetry in mid-calf and mid-thigh slices. The interface pressure of compression was measured at the same level.

RESULTS

Examples are presented showing that the narrowing of veins does not only depend on the exerted pressure but also on the body position and the resulting distortion of the tissue. In the prone and the standing position deep veins may show a greater reduction of the cross section area than in superficial veins.

CONCLUSION

MRI is a powerful method to assess venous narrowing by external compression. Especially in the standing position new insights regarding the effects of different compression devices may be expected.

Duplex scanning to evaluate the effect of compression on venous reflux

AIM

The aim of this study was to demonstrate the usefulness of Duplex in measuring venous reflux and changes in reflux caused by leg compression.

METHODS

Twelve patients with severe incompetence of the great saphenous vein (GSV) were investigated. A special Duplex probe was fixed by tapes on the mid-thigh portion of the incompetent GSV and reflux elicited by tip toeing was measured. Elastic and inelastic compression material with an interface supine pressure around 20, 40 and 60 mmHg was applied on the lower leg and the reflux measurement was repeated.

RESULTS

Increasing compression of the leg led to a progressive reduction of the reflux in the GSV. Ultimately reflux was completely abolished by inelastic compression with a median pressure of 86 mm Hg in the standing position. Elastic material exerting this pressure can achieve similar results but is not tolerated by patients.

CONCLUSION

Duplex is able to demonstrate a reduction of GSV reflux caused by compression of the lower leg, which explains one major beneficial effect of compression on the disturbed haemodynamics in venous incompetence.

Comparison of three portable instruments to measure compression pressure

AIM

Measurement of interface pressure between the skin and a compression device has gained practical importance not only for characterizing the efficacy of different compression products in physiological and clinical studies but also for the training of medical staff.

METHODS

A newly developed portable pneumatic pressure transducer (Picopress®) was compared with two established systems (Kikuhime® and SIGaT tester®) measuring linearity, variability and accuracy on a cylindrical model using a stepwise inflated sphygmomanometer as the reference. In addition the variation coefficients were measured by applying the transducers repeatedly under a blood pressure cuff on the distal lower leg of a healthy human subject with stepwise inflation.

RESULTS

In the pressure range between 10 and 80 mmHg all three devices showed a linear association compared with the sphygmomanometer values (Pearson r>0.99). The best reproducibility (variation coefficients between 1.05-7.4%) and the highest degree of accuracy demonstrated by Bland-Altman plots was achieved with the Picopress® transducer. Repeated measurements of pressure in a human leg revealed average variation coefficients for the three devices of 4.17% (Kikuhime®), 8.52% (SIGaT®) and 2.79% (Picopress®).

CONCLUSION

The results suggest that the Picopress® transducer, which also allows dynamic pressure tracing in connection with a software program and which may be left under a bandage for several days, is a reliable instrument for measuring the pressure under a compression device.

Is low compression pressure able to improve venous pumping function in patients with venous insufficiency?

Background

A too high resting pressure of compression devices is poorly tolerated and may cause skin defects, especially in patients with concomitant arterial occlusive disease.

Aim

To investigate whether low compression pressure will improve venous pumping function in patients with venous incompetence.

Material and methods

Venous pumping function was assessed in 20 patients with severe reflux in the great saphenous vein by measuring ejection fraction (EF) using strain-gauge plethysmography. Measurements were repeated after application of knee-high medical compression stockings and of inelastic bandages applied with a pressure of 20, 40 and 60 mmHg in the supine position.

Results

EF was significantly reduced compared with healthy controls. Compression stockings exerting a median pressure of 27 mmHg (interquartile range [IQR] 25–29) in the supine and 30.5 mmHg (IQR 28.25–34.25) in the standing position produced a moderate, non-significant improvement of EF of 17%. Inelastic bandages with a resting pressure of 20.5 mmHg (IQR 20–22) in the supine position resulting in a standing pressure of 36 mmHg (IQR 33–40.75) led to a significant increase of EF of 61.5% ( P < 0.01). A further increase of the resting pressure to 40 and 60 mmHg achieved an increase of the EF of 91% and 98%, respectively ( P < 0.001).

Conclusions

In patients with venous pumping failure, inelastic bandages produce a significant pressure-dependent increase of EF. A significant improvement in venous pumping function was achieved with inelastic bandages even at a resting pressure of 20 mmHg.

Thigh compression after great saphenous surgery is more effective with high pressure

AIM

Methods to compress thigh veins effectively after venous surgery or endovenous procedures are still disputed. The aim of this paper was to compare the clinical outcomes with three different compression devices as a function of the pressures exerted.

METHODS

Fifty-four patients undergoing invagination stripping of the great saphenous vein and side branch evulsion under local anaesthesia were treated postoperatively in sequential order by 1) thigh length compression stockings; 2) adhesive bandages; and 3) newly developed eccentric compression pads fixed with tapes and a thigh length stocking on top. Sub-bandage pressures were measured at mid-thigh level under these devices after application and one week later before compression was removed. Pain, hematoma, bleeding through the bandage, discomfort and skin irritations were recorded and rated as major or minor adverse events.

RESULTS

The lowest sub-bandage pressure of around 15 mmHg at thigh level in the lying position were found in group A under the compression stockings, which nominally provide 23-32 mmHg at ankle level. Group B and group C showed significantly higher values (median values of 47 and 68 mmHg respectively in lying position, P<0.001). The median pressure values in the three groups upon standing were 16 mmHg, 63 mmHg and 98 mmHg. One week later there was a pressure-drop in the lying position in the three groups of 13%, 64%, and 46% respectively. Major adverse events were seen in a total of 10 of 18 patients in group A, in 1/18 in group B, and in 0/18 in group C. Minor adverse events in the three groups consisting mainly of light discomfort for compression devices and local skin irritations were observed in 6, 6 and 15 cases respectively.

CONCLUSIONS

The best results with respect to the reduction of pain and hematoma were obtained when eccentric compression pads were taped to the skin of the thigh and a compression stocking was worn on top. A possible explanation for these observations is the very high local pressures under the eccentric device.

Thigh compression

The aim of this overview is to discuss the role of thigh compression for the management of venous and lymphatic diseases. The most important indications for thigh compression are prevention and treatment of sequelae of superficial vein procedures (surgery or endovenous procedures), prevention and therapy of deep vein thrombosis (DVT), post-thrombotic syndrome and lymphoedema. The intended effects depend mainly on narrowing/occlusion of deep and superficial veins on which the body position and the applied pressure play a crucial role. While in the horizontal position thigh veins can be narrowed by the light pressure of a thromboprophylactic stocking, much higher pressure is needed to compress thigh veins effectively during standing and walking. This is shown by magnetic resonance imaging (MRI) performed in the supine and upright position. Using pads, rolls or specially designed devices, the local pressure under conventional compression garments or bandages over a treated vein can be increased considerably. In patients with deep valve incompetence, beneficial haemodynamic effects of strong thigh compression have been demonstrated, but clinical studies in this field are still lacking. Thigh compression reduces oedema in patients with DVT and lymphoedema.

Inelastic compression increases venous ejection fraction more than elastic bandages in patients with superficial venous reflux

Aim

To investigate the influence of compression bandages, manufactured using materials with different elastic properties, on the impaired venous pumping function in patients with venous insufficiency.

Methods

Ejection volume (EV) and ejection fraction (EF) were measured using strain gauge plethysmography distal from the patella without and with elastic and inelastic compression bandages in a total of 30 patients with major venous reflux in the great saphenous vein. The interface pressure of the bandages was measured simultaneously in the medial gaiter area. Normal values of EV and EF were obtained from 15 healthy controls.

Results

Patients with venous insufficiency showed a statistically significant reduction of EV and EF compared to controls. Elastic bandages with an average pressure of 42 mm Hg in the supine position achieved a moderate increase of EV and a significant improvement of EF (p < .01), while inelastic bandages applied with comparable resting pressure (41 mm Hg) raised EV and EF into a normal range (p < .001). The improvement of the ejection fraction correlates well with the pressure differences between standing and lying (Static Stiffness Index) and between muscle systole and diastole during exercise (Pearson r = 0.69 and 0.74 respectively, p < .001). Elastic bandages applied with high stretch in order to achieve standing pressures comparable to those of inelastic bandages (>60 mm Hg) led only to a minor improvement of the venous pumping function.

Conclusions

Ejected volume and ejection fraction, which are severely reduced in venous insufficiency, can be increased by compression therapy. Inelastic compression is much more effective than elastic bandages, and is able to normalize venous pumping function. With elastic bandages EV and EF always remain below the normal range even when applied with high stretch producing a resting pressure that is barely tolerable.

Quantification of venous reflux by means of some duplex scanner and light reflection rheography parameters and its correlation with chronic venous insufficiency symptoms

BACKGROUND

The quantification of venous reflux is rarely made but it is valuable for studying the natural history of CVI, its prognostic implications and the therapy effectiveness. We have evaluated some parameters of chronic venous insufficiency, caused by valvular incompetence, by means of duplex scanner and light reflection rheography searching for a better correlation with the clinical stages of vein disease.

METHODS

We have examined 107 patients (35 males, 72 females; aged 22-78, mean 61.5 +/- 14.3) with long saphenous insufficiency in different clinical stages and measured the venous reflux, the reflux duration, the reflux grade, the vein diameter near the saphenofemoral junction with the duplex scanner and the refilling time with the light reflection rheography. The reproducibility of the studied techniques has been determined by examining 20 legs four times each in the same day or on different days. Statistical analysis of the data was performed by means of the variance analysis followed by the Waller-Duncan test.

RESULTS

The venous reflux, the venous diameter and the refilling time can easily range between mild and severe insufficiency: reflux is 6.3 +/- 2.5 ml/sec at stage I; 27.5 +/- 10.1 at stage III; venous diameter is 6.04 +/- 1.4 at stage I; 10.6 +/- 2.2 at stage III; refilling time is 23.6 +/- 9.6 at stage I; 5.4 +/- 2.4 at stage III. The reflux time and reflux grade are unable to separate the various CVI stages.

CONCLUSIONS

The measurement of venous reflux, venous diameter and refilling time is simple, quick, reproducible; these indices are able to differentiate mild from severe CVI but unable to separate patients at the second stage of the venous disease from those at the third stage and then ineffective in the ulcer risk assessment but the reflux is highly predictable. The ulcer risk is practically absent for reflux < 12 ml/sec; highly probable for reflux > 15 ml/sec (20/46 cases; 43.4%).

Pulse wave velocity. A new calculation method

BACKGROUND

The increase in aortic Pulse Wave Velocity (PWV) is considered a surrogate marker of vascular disease; it can be non-invasively assessed by means of an indirect method calculating the time that the pulse wave takes to travel a definite distance along the vasculature; the distance/time ratio corresponds to the velocity measure. The presentation of a new calculation method is the aim of the present study.

METHODS

A duplex scanner at the common carotid artery, the abdominal aorta at the prebifurcation site and the femoral common artery levels, was performed on 127 out-patients with risk factors, 38 of which were affected by clinical vascular disease, and on 50 healthy subjects (control group). The spectral analysis from these three sites was registered simultaneously with an ECG trace and the interval between the R wave apex and the spectral complex systolic foot was measured. The Transit Time (TT) was calculated by the difference between the values obtained from the proximal and distal measurement sites and PWV dividing the distance between them by the TT (PWV = Distance/TT); statistical significance and intra and inter observer variation coefficient, expressed as mean +/- standard deviation, were calculated by the analysis of variance and Turkey test, the correlation with the major risk factors and the intima-media thickness by the multivariate analysis.

RESULTS

The PWV is increased in the patients group compared to control group (p < 0.001). Multivariate analysis shows a positive correlation with age, hypercholesterolemia, arterial hypertension, diabetes mellitus, intima-media thickness and arterial disease, no correlation was found with the smoking habit. The "patients" group shows an increased PWV in those with atherosclerotic plaques and/or clinical vascular disease compared to non atherosclerotic patients with risk factors (p < 0.001); the intra and inter observer variation coefficient ranged between 4.87 +/- 1.82% and 8.06 +/- 3.16% respectively.

CONCLUSIONS

The proposed PWV measurement method is simple, quick, reproducible and repeatable, it can separate healthy subjects from patients with risk factors, atherosclerotic plaques and clinical vascular disease. Due to the strong correlation with age, normal values in different age groups are necessary before the PWV can be used as a marker of vascular disease.

[Recurrence of varicose veins after treatment. Multicenter study by the Italian Doppler Club, Clinical and Technological Society]

BACKGROUND

The first results of a multicentric study dealing with recurrent varicose veins after surgery are presented. The aims of the study are: identifying the type of varicose vein, specifying the most frequent complaints (esthetical or functional), locating the causes of recurrence, establishing the causes and the most frequent seat of recurrence, clarifying whether it is enough to call recurrent all the varicose veins which appear after surgery or whether it is necessary to distinguish various typologies.

METHODS

194 patients (139 women and 55 men) aged 51.6 average (range 28-87), have been studied up to now with duplex and color scanner following a precise protocol which consisted of three stages: before treatment, within 2 months from treatment and after recurrence of varicose veins or venous insufficiency symptoms.

RESULTS

Recurrent varicose veins represented 65.7%, residual ones 14.3%, new ones 2.5%. It has not been possible to identify the type of varicose vein in 8.3% of cases. Stripping of the great saphenous veins was carried out in 88% of cases, short stripping in 4.1%, stripping of the short saphenous veins in 6.9%. Recurrent varicose veins were due to technical error in 78.7% of cases, to diagnostic error in 9.2%, to unidentifiable causes in 12% of cases.

CONCLUSIONS

Data relating to the prospective study of the research will be published in subsequent papers.

[Reliability of sedation in MRI]

In our work we have an enumeration of 1527 sedation cases to carry out RM exams with non co-operating patients, most of them in pediatric age. During the examination the patients were monitored using oximeter and observed by closed circuit camera. The meaningless complications head us to think that deep sedation is a reliable procedure which allows us to work out RM exams during a day-hospital regime.