Plymouth Health CommunityNICE Guidance Implementation

Group

Workshop Two: Debriding agents and specialist

wound care clinics. Pressure ulcer risk assessment & prevention

5th December 2002

Randomised Controlled Trial (RCT)

A trial in which subjects are randomly assigned to either a group receiving an intervention that is being tested or control group receiving an alternative or no intervention. The results compare the outcomes of the different groups.

Systematic Reviews

A review of research-based evidence on a topic in which the evidence has been systematically identified, appraised and summarised according to pre-determined criteria .

Plymouth Health CommunityNICE Guidance Implementation Group

Use of debriding agents & specialist wound care clinics for difficult to heal surgical wounds. Technology Appraisal Guidance (TGA 24).

Issue date: April 2001

Review date: March 2004

Background• Delays to healing caused by several

intrinsic & extrinsic factors - including debris within wound

• No reliable figures for wounds that become difficult to heal - 21,000 per year

• Trend towards community care• High levels of knowledge, skill & advice• Expert services for most intractable

Debridement

• Removal of devitalised necrotic or infected tissue or fibrin (‘debris’) from a wound

• Different methods of debridement, e.g. surgical, mechanical or autolytic

• Range of wound care products thought to promote autolytic healing: ‘modern dressings’

• Frequency of dressing change and patient acceptability important factors in choice of dressing

Cost to the NHS

• Actual costs of treating difficult to heal surgical wounds not been measured

• Health care costs not only unit costs of dressing used, but the frequency of dressing changes needed, over period of time. Nursing costs

• No. of patients affected not known, clinical practice varies. Difficult to estimate the cost and service impact on the NHS of changes in debriding agents or specialist wound care services.

Systematic review on effectiveness of debriding agents

To determine clinical and cost effectiveness of debriding agents in treating

surgical wounds healing by secondary intention

To evaluate the clinical and cost effectiveness of treating patients at

specialist wound care clinics, compared to conventional care

Types of evidence

Primary outcomes were wound healing and cost

• 17 trials selected all using autolyic method of debridement (13 surgical wounds)

•No studies investigated other types of debridement.

•No studies investigated specialist wound care clinics

Quality of evidence

Majority had methodological flaws:

• trials had small sample sizes (median: 43)• did not report randomisation or blinding

• did not report baseline characteristics

• did not report results in sufficient detail to calculate summary estimate of the treatment effect

•statistical tests used to compare the treatment groups often not reported, or no statistical test was used.

Findings of clinical effectiveness

Results should be interpreted with caution due to poor quality of the studies, unknown effects of potential confounding factors...

Clinical effectiveness

• No RCT evidence to support any

particular method of debridement

• Some evidence to suggest a

beneficial effect of modern dressings

for surgical wounds on other

outcomes, e.g. pain, dressing

performance and resource use. But

these outcomes difficult to assess and

subject to bias in unblinded studies

Cost effectiveness

• Four economic evaluations

• No evaluations comparing two

different types of modern

dressing, or of specialist wound

clinics

•Partial evidence to favour

modern dressings - lower costs

•Quality of effectiveness and cost

effectiveness analyses poor

Guidance• No evidence for particular method of

debridement. Modern dressings may

reduce pain and be acceptable to

patients

• Choice of debriding agent based on

impact on comfort, odour control and

other aspects relevant to patient

acceptability, wound type, and cost.

• Require structured approach to care

Implications for future research

• multi-centre trials comparing different types of modern dressing

• economic evaluations of modern dressings

•research into other debriding methods

•studies looking at the clinical & cost effectiveness of specialised wound care clinics

•epidemiological studies to evaluate the prevalence and cost to the NHS of treating such surgical wounds

Plymouth Health CommunityNICE Guidance Implementation Group

Pressure ulcer risk assessment and prevention. Inherited Clinical Guideline B

Issue date: April 2001

Review date: 2005

Evidence - linked information

• Identifying individuals at risk

• Use of assessment scales

• Recognising risk factors

• Skin inspection

• Pressure redistributing devices & use of aids

• Positioning & seating

• Education & training

Recommendations graded on their evidence base as follows:

1. Generally consistent finding in a majority of multiple acceptable studies

2. Either based on a single acceptable study, or a weak or inconsistent finding in multiple acceptable studies

3. Limited scientific evidence which does not meet all the criteria of acceptable studies or absence of directly applicable studies of good quality. Includes expert opinion.

i

Types of evidence

Two clinical issues subject of systematic review & provided evidence at level 1:-

1. risk assessment scales (McGough 1999).

2. pressure redistributing devices (EHCB 1995; Cullum et al. 2000)

• Most of the remaining evidence appraised at level 3

Quality of evidence

Both authors reported the poor quality of studies & trials available for review, e.g. lack of baseline comparability & poor descriptions of wound assessment, lack of blinding, inadequate sampling & attention to randomisation, inattention to inter-rater reliability etc,

Recommendations

Some research evidence that could be translated into recommendations:-

•Insufficient evidence to recommend using risk assessment scores - decisions made on holistic assessment of individual’s risk

•Individuals at risk should not be placed on standard foam mattresses

Guideline development

•Formal consensus development process to integrate the different evidence sources and, where there was a weak research base, agree recommendations based on current best practice. Appraisal of robustness of national guidelines.

Recommendations for future research

Potential future research agenda for pressure ulcer risk assessment and prevention is very large.

Attention to methodological standards

Need for well designed independent, multi-centred, randomised controlled trials re different types of pressure devices in variety of settings.