EXPERIENCE WITH VACUUM-ASSISTED CLOSURE DEVICE IN THE MANAGEMENT OF BENIGN CHRONIC LEG ULCERS

Abstract

Background: Chronic leg ulcers are commonly encountered in clinical practice. They often last several months to years, with a negative social and economic impact on the patient. Rapidly effective modalities of treatment are therefore to be desired.

Vacuum-Assisted-Closure (VAC) device in the management of benign chronic ulcers has been reported in the literature; however, there are limited reports on its use in the West African sub-region.

Aim: To assess the efficacy of VAC therapy in the management of chronic leg ulcers in our

patients.

Patients and Method: Case records of patients with chronic leg ulcers presenting at the plastic surgery unit of Imo State University Teaching Hospital, who were managed using the Vacuum Assisted Closure (VAC) device were reviewed. The period of study was from July 2008 to June 2010 (24 months). Data obtained were analyzed using descriptive statistics.

Results: Forty one patients with 52 leg ulcers were managed in the period under review. M:F = 3:1

Their ages ranged from 13 to 82 years with a mean age of 43years. Sickle cell ulcers and Post traumatic ulcers were commoner in the young adults, while the vascular ulcers were commoner in the middle aged and elderly.

Patients with sickle cell and vascular ulcers were more likely to have multiple ulcers. The sickle cell and venous ulcers had the longest duration but most rapid response to VAC therapy. The arterial ulcers showed poor response. Skin grafting after VAC therapy was excellent in all patients.

Conclusion: VAC is a useful adjunct in the management of benign chronic leg ulcers. It is exceptionally effective in venous, sickle cell and post traumatic ulcers, which are quite common in this environment.

Introduction

Chronic leg ulcers are a commonly encountered problem in clinical practice. The rising incidence in many western studies has been attributed to an increasing population age.1 The aetiology is varied and include chronic venous and arterial insufficiency, trauma (including burns), sickle cell disease and diabetes mellitus.2,3 They present a healthcare burden which is costly, and often associated with poorly coordinated visits to multiple health facilities.4 Several studies have shown that, these ulcers often last several years, with a significant negative impact on the quality of life of the patients.5,6,7. In recent years a number of publications have focused on different strategies to reduce costs and increase health-related quality of life for patients through choice of cost-effective treatment options 8,9,10

The use of negative pressure in management of wounds was first described by Fleischmann et al in 1993.11 The Vacuum Assisted Closure (VAC) system by applying a regulated continuous or intermittent pressure, has been shown to increase blood flow by up to 4 times the basal level, increase the rate of granulation tissue formation by up to 40 to 103%, reduction in local oedema and decrease significantly wound bacterial counts.12,13

Vacuum assisted closure therapy has been found a useful adjunct in the management of chronic and difficult to heal wounds14

This study reviews the use of VAC in the management of chronic leg ulcers of varying aetiologies in Imo State University Teaching Hospital, and was carried out at the Plastic Surgery Division of Imo State University Teaching hospital. The Hospital is located in Orlu, a sub-urban town in Eastern Nigeria. It is one of the few tertiary health institutions offering Plastic surgery services to the Eastern and Southern parts of Nigeria. Most of the patients however come from neighbouring rural communities and are mainly of a low socioeconomic group.

Reports

Patients and Methods

Case records of patients with chronic leg ulcers presenting at the Plastic Surgery division of Imo State University Teaching Hospital, who were managed using the Vacuum Assisted Closure (VAC) device were reviewed. The period of study was from July 2008 to June 2010 (24 months).

In addition to the use of the VAC system, patients were placed on bed rest, haematinics, analgesics and antibiotics where necessary. None was transfused blood.

Wounds were cleaned with normal saline and necrotic tissue excised before application of the VAC sponge.

Patients with invasive wound infection had the infection controlled before instituting VAC therapy.

The applications were done in the ward using a clean controlled approach.

VAC sponges were changed every 3 to 5 days or when the canister was full.

Skin grafting was subsequently done at the next theatre session.

Data on age, sex, number and duration of ulcers, diagnosis, duration of VAC therapy and outcome of skin cover were extracted from the case records and analyzed using descriptive statistics.

Results

Forty one patients with 52 leg ulcers were managed in the period under review. There were 31 males and 10 female. M:F = 3:1. All ulcers were commoner in males than females as shown in fig 2.

Their ages ranged from 13 years to 82 years (mean age = 43 years). Sickle cell ulcers and Post traumatic ulcers were commoner in the young adults, while the vascular ulcers were commoner in the middle aged and elderly. Fig 3

Ten patients had sickle cell ulcers, 9 had venous ulcers, 2 arterial ulcers, 11 had post traumatic leg ulcers, 7 diabetic ulcers and 2 post cellulitic as shown in table 1

Multiple ulcers were commoner in patients with ulcers of vascular aetiology.

Of the 7 patients presenting with multiple ulcers, 5 had bilateral leg ulcers.

The sickle cell and venous ulcers had a longer duration (mean duration of 47.8 months and 67.5 months respectively) while the diabetic and post traumatic ulcers had a relatively shorter duration.

The sickle cell and venous ulcers were usually ready for cover within 6 to 10 days of VAC therapy. The diabetic ulcers required up to 14days of VAC therapy. Both arterial ulcers showed poor response.

Skin grafting after VAC therapy had more than 95% take in all patients. The best results were however seen in patients with sickle cell and venous ulcers, who had an average graft, take above 98%. Table 1

All patients tolerated the VAC therapy, except for a female patient with Sickle cell ulcers who complained of pains all through the period of therapy

Conclusions

In our experience, VAC is a useful adjunct in the management of benign chronic leg ulcers. Although its initial cost appears high, it is a cost effective option in ensuring rapid improvement in the local wound conditions for successful wound cover. It is exceptionally effective in venous, sickle cell and post traumatic ulcers which are quite common in this environment.

Discussion

The ages of the patients in this study ranged from 13years to 85 years with a mean age of 43 years. This is a relatively young age compared to western studies.1,4while the demographic characteristics of our population may play a significant role in this, the prevalent types of ulcers in our study population may equally have accounted for this. Patients with sickle cell ulcers and post traumatic ulcers accounted for 51% of our patients. These ulcers are commoner in the young3 as was reflected in this study. Chronic leg ulcers have been shown to be associated with substantial treatment costs.8,15,16,17,18,19,20,21 The cost implications are further heightened in the younger patients in whom leg ulceration has been correlated with time lost from work and school, and job loss, with adverse effects on finances.22 Treatment options with rapid and consistent results are therefore desirable.

Post traumatic chronic leg ulcers were the commonest variety of chronic leg ulcers seen in our patients. Chronic venous disease is reported to be the commonest cause of chronic leg ulceration worldwide.23,24 The preponderance of post traumatic chronic leg ulcers in our patients may be an index of the efficiency or otherwise of acute traumatic wound care in our locality: With the Hospital located in a sub-urban setting, and most of its patients drawn from neighbouring rural communities, the dearth of medical personnel proficient in acute wound care in these rural communities may be responsible for the relative high prevalence of post traumatic chronic leg ulcers. The high level of poverty, illiteracy and ignorance may also be contributory.

VAC therapy was found to be effective in preparing most benign chronic ulcers for subsequent wound cover as reported in other studies.14 Most ulcers were ready for cover within 14days of VAC therapy. The best results were seen in patients with sickle cell disease and venous ulcers, where the wounds were usually ready for cover in an average of less than 7 days of VAC therapy (Fig. 3&4). Its efficacy in improving the local wound condition in sickle cell and venous ulcers may not be strange. VAC therapy is thought to improve local wound blood flow and reduce wound bacterial count, by mobilization of wound edema.11 This oedema is thought to play a significant role in the pathophysiology and chronicity of these ulcers.24,25 The response with diabetic ulcers was not that rapid and required more frequent VAC dressing changes. The slower response of the diabetic ulcers may not be unrelated to the fact that other factors such as decreased cell and growth factor response, further contribute to slowing down the healing process in persons with diabetic ulcers.26

The arterial ulcers responded poorly to VAC care which had to be discontinued. Objective assessment of local blood flow in these wounds was not possible, as facilities for such were not available at the time. Perhaps the local blood flow was below the level critical to sustain wound healing. VAC therapy may therefore not be a substitute for revascularization procedures in patients with significant arterial insufficiency. This affirms the need for objective vascular assessment of the leg in patients with non healing wounds of suspected arterial insufficiency.

For patients with bilateral leg ulcers, managing both ulcers in parallel using one VAC device was quite a challenge. There may therefore be a need for a modification of the VAC construct to improve on the flexibility of its use.

Graft take following VAC wound care in all patients was excellent. This is an indication of the efficacy of VAC therapy in achieving rapid improvements in wound conditions in most types of chronic leg ulcers.

The initial high cost of the VAC device has been highlighted as a draw back in its clinical use27 This device once acquired by the hospital is cost effective when compared with the true cost of using conventional dressings over several months to years with associated frequent travels and use of healthcare facilities. In a 2003 Swedish survey of 138 patients with chronic venous ulcers,28 the mean duration of ulcer treatment using conventional dressings was 21 months. In this series, the mean ulcer duration at presentation in patients with venous ulcers was 67.5 months. With VAC therapy however, these ulcers were usually ready for cover within 7 days and wound cover and definitive vascular procedures were usually done in one theatre session within 10 days of admission, with excellent results.

Fig 1.

Vacuum Assisted Closure (VAC) device

Fig 2.

Age distribution of patients

Fig 3.

Sex distribution of ulcers

Table I

Type of Ulcer	N0. of Patients	N0. of Ulcers	N0. of Ulcers per patient	Mean duration of Ulcers at presentation	Mean Period of VAC therapy	Mean graft take
Sickle Cell Ulcers	10	18	1.8	47.8 months	6.6 days	99.7%
Venous Ulcers	9	11	1.2	67.5 months	6 days	98.8%
Arterial Ulcers	2	2	1	48 months	discontinued	-
Post Traumatic	11	11	1	5.3 months	9.2 days	98%
Post Cellulitic Ulcers	2	2	1	1.5 months	10 days	98%
Diabetic ulcers	7	7	1	3.3 months	15 days	95.7%

Fig.4a.

venous ulcer: Before VAC therapy

Fig.4b.

venous ulcer: After 6 days of VAC therapy

Fig.5a.

Sickle cell ulcer: Before VAC therapy

Fig5b.

Sickle cell ulcer: After 7 days of VAC therapy