[Wound bed preparation of chronic wounds with ultrasound]

Use of low-frequency contact ultrasonic debridement with and without polyhexamethylene biguanide in hard-to-heal leg ulcers: an RCT

OBJECTIVE

The primary aim of this research was to investigate the combination effect of polyhexamethylene biguanide (PHMB) and low-frequency contact ultrasonic debridement (LFCUD) on the bacterial load in hard-to-heal wounds in adults, compared with ultrasonic debridement alone. Secondary outcomes included wound healing, quality of life (QoL) and pain scores.

METHOD

In this single-blinded, randomised, controlled trial participants were randomised to two groups. All participants received LFCUD weekly for six weeks, plus six weeks of weekly follow-up. The intervention group received an additional 15-minute topical application of PHMB post-LFCUD, at each dressing change and in a sustained dressing product. The control group received non-antimicrobial products and the wounds were cleansed with clean water or saline. Wound swabs were taken from all wounds for microbiological analysis at weeks 1, 3, 6 and 12.

RESULTS

A total of 50 participants took part. The intervention group (n=25) had a lower bacterial load at week 12 compared with the control group (n=25) (p<0.001). There was no difference in complete wound healing between the groups (p=0.47) or wound-related QoL (p=0.15). However, more wounds deteriorated in the control group (44%) compared with the intervention group (8%, p=0.01). A higher proportion of wounds reduced in size in the intervention group (61% versus 12%, p=0.019). Pain was lower in the intervention group at week six, compared with controls (p=0.04).

CONCLUSION

LFCUD without the addition of an antimicrobial agent such as PHMB, cannot be recommended. Further research requires longer follow-up time and would benefit from being powered sufficiently to test the effects of multiple covariates.

Therapeutic ultrasound for venous leg ulcers

BACKGROUND

Venous leg ulcers are a type of chronic, recurring, complex wound that is more common in people aged over 65 years. Venous ulcers pose a significant burden to patients and healthcare systems. While compression therapy (such as bandages or stockings) is an effective first-line treatment, ultrasound may have a role to play in healing venous ulcers.

OBJECTIVES

To determine whether venous leg ulcers treated with ultrasound heal more quickly than those not treated with ultrasound.

SEARCH METHODS

We searched the Cochrane Wounds Specialised Register (searched 19 September 2016); the Cochrane Central Register of Controlled Trials (CENTRAL; the Cochrane Library 2016, Issue 8); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations, MEDLINE Daily and Epub Ahead of Print) (1946 to 19 September 2016); Ovid Embase (1974 to 19 September 2016); and EBSCO CINAHL Plus (1937 to 19 September 2016). We also searched three clinical trials registries and the references of included studies and relevant systematic reviews. There were no restrictions based on language, date of publication or study setting.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared ultrasound with no ultrasound. Eligible non-ultrasound comparator treatments included usual care, sham ultrasound and alternative leg ulcer treatments.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the search results and selected eligible studies. Details from included studies were summarised using a data extraction sheet, and double-checked. We attempted to contact trial authors for missing data.

MAIN RESULTS

Eleven trials are included in this update; 10 of these we judged to be at an unclear or high risk of bias. The trials were clinically heterogeneous with differences in duration of follow-up, and ultrasound regimens. Nine trials evaluated high frequency ultrasound; seven studies provided data for ulcers healed and two provided data on change in ulcer size only. Two trials evaluated low frequency ultrasound and both reported ulcers healed data.It is uncertain whether high frequency ultrasound affects the proportion of ulcers healed compared with no ultrasound at any of the time points evaluated: at seven to eight weeks (RR 1.21, 95% CI 0.86 to 1.71; 6 trials, 678 participants; low quality evidence - downgraded once for risk of bias and once for imprecision); at 12 weeks (RR 1.26, 95% CI 0.92 to 1.73; 3 trials, 489 participants; moderate quality evidence - downgraded once for imprecision); and at 12 months (RR 0.93, 95% CI 0.73 to 1.18; 1 trial, 337 participants; low quality evidence - downgraded once for unclear risk of bias and once for imprecision).One trial (92 participants) reported that a greater percentage reduction in ulcer area was achieved at four weeks with high-frequency ultrasound, while another (73 participants) reported no clear difference in change in ulcer size at seven weeks. We downgraded the level of this evidence to very low, mainly for risk of bias (typically lack of blinded outcome assessment and attrition) and imprecision.Data from one trial (337 participants) suggest that high frequency ultrasound may increase the risk of non-serious adverse events (RR 1.29, 95% CI 1.02 to 1.64; moderate quality evidence - downgraded once for imprecision) and serious adverse events (RR 1.21, 95% CI 0.78 to 1.89; moderate quality evidence downgraded once for imprecision).It is uncertain whether low frequency ultrasound affects venous ulcer healing at eight and 12 weeks (RR 3.91, 95% CI 0.47 to 32.85; 2 trials, 61 participants; very low quality evidence (downgraded for risk of bias and imprecision)).High-frequency ultrasound probably makes little or no difference to quality of life (moderate quality evidence, downgraded for imprecision). The outcomes of adverse effects, quality of life and cost were not reported for low-frequency ultrasound treatment.

AUTHORS' CONCLUSIONS

It is uncertain whether therapeutic ultrasound (either high or low frequency) improves the healing of venous leg ulcers. We rated most of the evidence as low or very low quality due to risk of bias and imprecision.

Therapeutic Ultrasound in Lower Extremity Wound Management

In medical practice, ultrasound (US) is used for diagnosis and therapy. High-frequency (1-4 MHz) and low-frequency (20-120 KHz) therapeutic US are relevant to wound healing. The heating effects of high-frequency US are important, whereas the mechanical effects of low-frequency US must be considered. The physiological effects of low-frequency US include metabolic enhancement, perfusion, wound cleansing, and the acceleration of wound granulation. The therapeutic efficacy of US depends on dose (W/cm2 time)and dosage (frequency of application, series). At adequate doses, high-frequency and low-frequency therapeutic US induce in vitro cell proliferation; protein synthesis; and the production of cytokines by fibroblasts, osteoblasts, and monocytes. The mechanical effects of low-frequency US cause transient cavitation in wound surfaces for soft and smooth wound cleaning, ulcer debridement, and the stimulation of granulation. These effects can be determined in clinical studies, though the quality of the studies done so far and of the evidence of the usefulness of US is poor. Nevertheless, high-frequency and low-frequency US may be reasonable options in the management of chronic wounds.

Therapeutic ultrasound for venous leg ulcers

BACKGROUND

Venous leg ulcers pose a significant burden for patients and healthcare systems. Ultrasound (US) may be a useful treatment for these ulcers.

OBJECTIVES

To determine whether US increases the healing of venous leg ulcers.

SEARCH STRATEGY

We searched the Cochrane Wounds Group Specialised Register (searched 24 February 2010); The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2010); Ovid MEDLINE (1950 to February Week 2 2010); In-Process & Other Non-Indexed Citations (searched 24 February 2010); Ovid EMBASE 1980 to 2010 Week 07; EBSCO CINAHL 1982 to 24 February 2010.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing US with no US.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the search results and selected eligible studies. Details from included studies were summarised using a data extraction sheet, and double-checked. We tried to contact trial authors for missing data.

MAIN RESULTS

Eight trials were included; all had unclear, or high, risks of bias, with differences in duration of follow-up, and US regimens. Six trials evaluated high frequency US and five of these reported healing at 7 - 8 weeks. Significantly more patients healed with US than without it at 7 - 8 weeks (pooled RR 1.4, 95% CI 1.0 to 1.96), but later assessments at 12 weeks showed the increased risk of healing with US was no longer statistically significant (pooled RR 1.47, 95% CI 0.99 to 2.20). One poor-quality study of high-frequency US found no evidence of an effect on healing after three weeks' treatment.Two trials evaluated low frequency US and reported healing at different time points. Both trials reported no evidence of a difference in the proportion of ulcers healed with US compared with no US: both were significantly underpowered.

AUTHORS' CONCLUSIONS

The trials evaluating US for venous leg ulcers are small, poor-quality and heterogeneous. There is no reliable evidence that US hastens healing of venous ulcers. There is a small amount of weak evidence of increased healing with US, but this requires confirmation in larger, high-quality RCTs. There is no evidence of a benefit associated with low frequency US.

Therapeutic ultrasound for venous leg ulcers

BACKGROUND

Venous leg ulceration is a common problem, representing a significant burden on the patient and the healthcare system. They are caused by venous insufficiency and tend to be chronic and recurring. Management usually includes use of wound dressings plus compression stockings or bandages. It has been suggested that therapeutic ultrasound may have an adjuvant effect and promote healing however its effects are unclear.

OBJECTIVES

To determine whether therapeutic ultrasound increases the healing of venous leg ulcers.

SEARCH STRATEGY

We searched the Cochrane Wounds Group Specialised Register (August 2007), The Cochrane Central Register of Controlled Trials (CENTRAL) - The Cochrane Library Issue 3, 2007, Ovid MEDLINE - 1950 to July Week 4 2007, Ovid EMBASE - 1980 to 2007 Week 31, Ovid CINAHL - 1982 to August Week 1 2007.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing therapeutic ultrasound with placebo (sham) ultrasound, or other (standard) treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the results of the searches for eligible RCTs and obtained full reports. A third author assessed the results of the update searches for eligible RCTs. Details from the eligible studies were extracted and summarised by a review author using a data extraction sheet. Attempts were made to contact trial authors to obtain missing data or for clarification.

MAIN RESULTS

A total of eight eligible trials were identified and were all of either medium or high risk of bias. Five trials compared ultrasound therapy with placebo (sham) ultrasound, three trials compared ultrasound therapy with standard treatment. Trials varied in terms of ulcer size, regimen and duration of follow up. No trials individually found a statistically significant difference in the number of ulcers healed between any of the therapies, however on pooling trials (different durations of follow up) for the outcome of risk healing, significantly more ulcers were completely healed with ultrasound (RR 1.49, 95% CI 1.07 to 2.09). Some trials also found that ultrasound increases the rate of change of wound size and/or reduces the size of existing ulcers, whilst other trials did not find this effect to be significant. When all trials reporting percentage ulcer area remaining were pooled there was a significant benefit associated with ultrasound (WMD -5.34%, 95% CI -8.38 to -2.30).

AUTHORS' CONCLUSIONS

The available evidence suggests that ultrasound may increase healing of venous leg ulcers. These conclusions are based on the results of only eight small studies of generally poor quality and therefore should be interpreted with caution.

Bewährte und aktuelle Verfahren in der Wundheilung

Most chronic wounds are caused by arterial or venous vascular disease. Wound care is an interdisciplinary task and economic challenge. Numerous new wound dressings and treatment methods have been introduced recently. Basic research has enhanced our understanding of stimulation and inhibition of wound healing. Well-constructed clinical studies have shown some traditional approaches to be effective and others, less so. Successful wound healing requires treatment of the underlying disease as well as correction of local factors that may delay healing. The choice of dressings must be based on continuous re-assessment of the wound. Modern approaches for the most common types of chronic wounds, as well as options such as vacuum treatment and tissue-engineered skin are presented along with information on latest rules for reimbursement for wound care in Germany.

Methicillin-resistenter Staphylococcus aureus (MRSA) in chronischen Wunden: Therapeutische Optionen und Perspektiven. Methicillin-resistant Staphylococcus aureus (MRSA) in chronic wounds: Therapeutic options and perspectives

The contamination of chronic wounds with Methicillin-resistant Staphylococcus aureus (MRSA) represents a world-wide increasing problem. Although it is still unclear whether bacterial contamination is a relevant factor for delayed wound-healing, verification of MRSA contamination has significant logistic consequences for the medical institution as well as for the patient. In particular, if MRSA contamination progresses towards a systemic infection, options for antibiotic therapy are greatly limited. In this article, we discuss current therapeutic standards and potential alternatives for eradication of MRSA. There is evident need for effective, novel approaches for elimination of MRSA from chronic wounds that avoid the development of bacterial resistance; otherwise therapeutic alternatives for antibacterial treatment of chronic wounds will become more limited.

Optionen des Debridements in der Therapie chronischer Wunden. Options for debridement in the therapy of chronic wounds

Debridement is defined as the removal of non-vital tissue from wounds. In chronic wounds, debridement means the elimination of necrosis as well as the clearing away of wound dressings, foreign bodies, and other non-vital substances. Sufficient debridement represents one basic prerequisite for a non-delayed wound-healing process. In addition to treating the causal factors for delayed wound healing, debridement should be the first step in an adequate phase-adapted wound-bed preparation for chronic wounds. This report aims to review the different options available in the execution of debridement in chronic wounds. The following therapeutic measures are available for the debridement of chronic wounds: surgery, maggot therapy, laser, ultrasound, hydrotherapy, wet-to-dry method, autolysis, proteolytic enzymes, osmotic or chemical debridement. There is no single correct debridement for all patients! Patients are individuals and therefore different methods of debridement may make sense. Which therapeutic option is chosen is determined by multiple factors. Moreover, depending on the wound milieu, the successive application of different methods can be useful.