Chronic non-healing ulcers are a frequent reason for admission to surgical wards, especially for patients with systemic conditions like diabetes mellitus. Diabetic foot ulcers are a major contributor, affecting up to 15% of individuals with diabetes during their lifetime [1]. In diabetes, impaired wound healing arises from multiple factors: peripheral neuropathy, poor glycaemic control, vascular insufficiency, and immune dysfunction, all hindering tissue repair and increasing infection risk [2]. Non-healing wounds, whether acute or chronic, significantly contribute to morbidity, extending hospital stays, raising healthcare costs, and potentially necessitating surgical interventions like debridement or amputation [3]. Chronic wounds affect at least 1% of the global population, with a higher prevalence among the elderly and those with comorbidities [4]. Factors such as infection, poor nutrition, and repeated trauma can further complicate healing in these patients [5]. Vacuum Assisted Closure (VAC) therapy, or Negative Pressure Wound Therapy (NPWT), is an advanced treatment that has revolutionized chronic wound management. VAC therapy applies controlled sub-atmospheric pressure to the wound bed via a sealed dressing connected to a vacuum pump. This negative pressure removes exudates, enhances tissue perfusion, promotes granulation tissue formation, reduces oedema, and limits bacterial colonization [6,7]. Clinical studies have shown VAC therapy accelerates wound healing compared to traditional methods, especially in complex wounds like diabetic foot ulcers, pressure sores, post-surgical wounds, and traumatic injuries [8,9]. VAC therapy improves clinical outcomes, shortens hospital stays, and lowers overall treatment costs [10]. Despite its advantages, conventional dressings like saline-moistened gauze and topical agents remain prevalent, particularly in resource-limited settings [11]. While providing a protective barrier and maintaining moisture, they often struggle with heavy exudates or microbial load [12]. Therefore, a comparative evaluation of VAC therapy versus conventional dressings in treating non-healing ulcers is crucial. This analysis aims to provide evidence-based guidance for optimizing wound care and improving patient outcomes in surgical settings.

AIM & OBJECTIVES:

To study and assess the outcomes of vacuum-assisted closure and conventional dressings in managing non-healing ulcers, focusing on wound healing rate, infection control, patient comfort, and overall recovery time. Also, to study the difference in end of treatment in both groups.

Our study was a prospective observational study including 60 patients who were admitted for non-healing ulcer and managed by vacuum assisted closure and conventional dressings at Veer Surendra Sai Institute of Medical Sciences and Research from

MAY 2023 - APRIL 2025  SAMPLE SIZE ESTIMATION: -

Desired sample size(n)=(Za+Zb) ^2{p1(1-p1) +p2(1-p2)}        (pl-p2)^2

Where, n=desired sample size of each group, Za=critical value and standard value for the corresponding level of confidence. At 95% confidence level or 5%level of significance (type 1 error), it is 1.96, Zb=critical value of the nominal distribution at beta. pl, p2=expected prevalence or prevalence based on previous research based on previous studies, p1=32[Success Rate by conventional Dressing], p2=68[Success Rate of VAC based on healthy granulation tissue formation] keeping power of study 80%and the type 1 error at 5% and d =36 ,n= [(1.96+0.84) ^2*(32*68+68*32)1/36^2 ,n=27 in each group, Total sample size =54 .Taking Fail to follow up to be 10%. Final Sample size to be taken as 60

Patients between the age group of 18 to 80 years willing to give consent were included in the study.

CONFLICTS OF INTEREST – There are no conflicts of interest. FINANCIAL SUPPORT AND SPONSORSHIP - Nil                                                                          ETHICAL APPROVAL-The study will be started after approval from the research ethics committee VIREC, Burla.

Table no: 01 Age distribution among the study population (n = 60)

The above table summaries age distribution (years) among the study population: out of 60 cases majority of cases, 29 (48.33%) are belong to 40 - 60 years, 21 (35%) are belongs to >60 year and 10 (16.67%) are belongs to <40 years of age respectively. Maximum age was 79 year and minimum age was 18 years.  The mean age of the study group was 54.68 ± 14.39 year.

Graph no: - 01 Shows age distribution the study population

Table no: 02 Gender distribution among the study population (n=60)

The above table summaries gender distribution among the study population, off which 37 (61.67%) are Male and 23 (38.33%) are female enrolled. In present study dominance of male patients are more. Hence, there was significant differences among the patients according to their Gender distribution, with p – value = 0.0109 {p<0.05}. For Test of Significance, here we use “Chi Square proportion Test {|z| – Test}”. The male to female ratio was 1.60:1

Graph no: - 02 Shows sex distribution among the study population

Table no: 03 Presenting Location of wounds among the study population (n=60)

The above table summaries Presenting location of wounds among the study population, off which 5 (8.33%) had location of wounds RT FOREARM, 12 (20%) had location of wounds LEFT ANKLE, 10 (16.66%) had location of wounds  LT FOREARM & RT ANKLE,7 (11.67%) had location of wounds LEFT FOOT and 8 (13.33%) had location of wounds RT FOOT, RT THIGH respectively.

Graph no: - 03 based upon location of wound the study population

Table no: 04 ORGANISMS BEFORE AMONG THE STUDY POPULATION (n=60)

Most common organism before cultured from the wounds was Staphylococcus aureus 27(45%).

Table no: 05 ORGANISMS AFTER AMONG THE STUDY POPULATION (n=60)

Most common Organism after cultured from the wounds was Staphylococcus aureus 5(8.33%).

Graph no: - 04 Shows organism before and after among the study population

Table no.: - 06 Comparison of mean hospital stay between two types of dressing groups

The above table 6, summaries comparison of mean hospital stays between two types of dressing groups: The mean Hospital stay (days) in Group - VAC was 14.36 ± 2.57 days. The mean Hospital stay (days) in Group - Cconventional was 20.76 ± 2.22 days.

Graph no: - 05 Comparison of mean hospital stay between two groups

Hospital stays (days) in Group - VAC was significantly less than Group - Cconventional, with   p – value = {p<0.001}. For Test of Significance, here we use “Paired |t| - Test”

Table no.: - 07 Comparison of End of Treatment between two types of dressing groups

The above table 07, summaries comparison of End of Treatment from the wounds between two types of dressing groups: Mostly patients are in both groups, 40% & 33.33% STSG in Group -VAC and in Group - Conventional respectively.

Graph no: - 06 Comparison of End treatment between two groups

Hence, there was no significant difference between two types of dressing groups, according to their End of Treatment from the wounds, with p – value = 0.5952 {p>0.05}. For Test of Significance, here we use “Chi Square Test”

Patient Demographics and Baseline Characteristics:

The study population primarily consisted of patients aged 40-60 years (48%). Males were more frequently affected by wounds, representing 62% of the cohort (37 out of 60), resulting in a male-to-female ratio of 1.60:1, consistent with existing literature.

Efficacy of NPWT on Wound Healing:

Negative pressure wound therapy (NPWT) significantly reduced the time to complete wound healing compared to conventional dressing methods (p < 0.0001, independent samples t-test). This finding aligns with previous research [13-15]:

• Armstrong and Lavery [13] reported a median time to complete closure of 56 days with NPWT versus 77 days with conventional saline dressings.
• Blume et al. [14] observed a higher proportion of diabetic foot ulcers (DFUs) achieving complete skin closure with NPWT.
• Singh et al. [15] found a mean time to complete wound closure of 41.2 days with NPWT compared to 58.9 days with conventional treatment.
• Vaidhya et al. reported shorter healing times with NPWT (17.2 days) than conventional dressings (34.9 days) in DFU patients in an Indian study.

Furthermore, patients treated with NPWT in our study experienced a shorter average hospital stay (14 days) compared to those receiving conventional dressings (21 days).

PICTURE 1. SHOWING NPWT

The accelerated healing associated with NPWT is likely due to macro deformation (wound stabilization, oedema reduction), micro deformation (cellular proliferation, angiogenesis stimulation), and decreased bacterial burden, collectively promoting granulation tissue formation. The shorter healing times observed in our study compared to some prior reports [13, 15] may reflect differences in endpoint definitions, as earlier studies focused on complete spontaneous closure, a goal not always achievable in all wounds which can lead to longer hospitalizations and higher costs. DFUs, in particular, may not always achieve spontaneous closure due to their dimensions.

While some studies have suggested NPWT might reduce re-amputation rates, this remains inconclusive [16]. Others have found no difference in amputation rates [17]. In our study, aggressive initial debridement minimized the need for secondary amputations in both treatment groups.

The mechanical strain induced by NPWT at the wound interface is thought to activate cellular pathways that promote proliferation and angiogenesis [18]. Increased levels of growth factors and cytokines, including fibroblast growth factor, transforming growth factor-β, interleukin-8, and vascular endothelial growth factor, have been implicated in the enhanced granulation tissue formation observed with NPWT [19, 20]. NPWT further optimizes the wound environment by reducing oedema and bacterial load, both of which can hinder granulation. Consistent with other studies [13, 15, 17], our study also found the median rate of granulation tissue formation was statistically significant.

PICTURE 2 & 3 SHOWING PRE VAC AND POST VAC RESPECTIVELY

Pain and Complications:

Pain associated with NPWT is thought to be caused by the suction applied to the wound. Disruption of granulation tissue during dressing changes can also contribute to discomfort. Pain assessment was performed in week 2, as the median healing times for the NPWT and control groups were approximately 14 and 21 days, respectively. Due to initial infection and necrotic tissue, all patients experienced significant pain early in the study, necessitating thorough debridement.

Haemorrhage is a rare but serious NPWT complication, especially in sternal wounds. In DFUs, major bleeding is typically linked to preventable factors such as inadequate haemostasis, exposed vessels, or excessive negative pressure. No significant bleeding events were reported in this study, which was conducted by trained surgical residents. Meticulous haemostasis and careful pressure monitoring are crucial for preventing this complication, although direct comparisons of bleeding complications between NPWT and conventional dressings for DFUs are lacking.

1. aureus was the most frequently cultured organism. While NPWT can potentially reduce bacterial load, some reports cite infection as an adverse event. Factors that could contribute to infection or its exacerbation with NPWT include inadequate debridement, retained foam, air leaks, sealing undiagnosed infections, and NPWT-induced bleeding. While beneficial effects on wound microbiology have been observed, NPWT should not replace standard infection control protocols.

Limitations of this study include the unequal distribution of Wagner grade between groups, even after stratified analysis. However, this could have been avoided with a larger sample. The subjective assessment of bleeding, while recorded, lacked an objective methodology due to logistical constraints. Future studies would benefit from including comparisons of cost, quality of life, and patient satisfaction.

Wound Size Reduction and Outcomes:

A larger proportion of wounds in the NPWT group (78.6%) decreased in size compared to the conventional dressing group (53.6%). These findings align with those of McCallon et al., Mark et al., and Blume et al. The endpoint of our study was a completely granulated wound or one that was ready for skin grafting or spontaneous healing. Both groups received similar treatments for wound closure, primarily split-thickness skin grafts (86.4% in NPWT vs. 93.33% in control). Our observations are consistent with Prabhdeep et al. Patients in the NPWT group required lower insulin doses, indicating NPWT may help with glycaemic control.

PICTURE 4 & 5 SHOWING PRE VAC AND POST VAC RESPECTIVELY

Success rates for complete granulation and preparedness for closure were higher in the NPWT group, and the need for amputation was lower, consistent with findings by Armstrong et al. Patients in the NPWT group also reported greater satisfaction regarding time to wound closure, antibiotic use, complications, and overall outcome. Apelqvist J et al. found a beneficial effect in terms of direct economic cost and resource utilization in patients treated with NPWT compared to standard moist wound therapy. Overall, NPWT appears to be a more effective, safer, and patient-satisfactory treatment option than conventional dressings for DFUs.

Bacterial loads ≥10⁵ CFU/g of tissue can impair healing. By promoting bacterial clearance, NPWT may facilitate wound healing.

Wound management remains a significant challenge. Delayed wound healing causes morbidity, disability, and burdens healthcare systems. Therefore, newer and advanced modalities like negative pressure wound therapy are needed. NPWT promotes wound healing by enhancing granulation tissue formation and wound closure more effectively than conventional dressings. NPWT reduces hospital stay, improves pus culture sensitivity, and improves outcomes, including greater success with split-thickness skin grafting. Our study suggests that NPWT is a promising technology in wound healing with broad applicability. When feasible, NPWT should be considered the preferred modality for wound management.

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