Clinical question
Should electrical stimulation versus sham/no electrical stimulation be used to promote healing of pressure injuries?
Context
Population:
Intervention:
Comparison:
Main Outcomes:
Setting:
Conflicts on Interest:
People at risk of heel pressure injuries
Electrical stimulation therapy plus standard wound care
Sham or no electrical stimulation therapy plus standard wound care
Any clinical setting
Hierarchy of outcome measures:
Outcome 1: Time to healing
Outcome 2: Complete healing (total/percent healed)
Outcome 3: Change in wound size (% change)
Outcome 4: Pain
Outcome 5: If infected at baseline, changes in signs and symptoms of infection
None
Evidence to Decision Framework
(Click on the individual judgements for more information)
Summary of Judgements
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Yes
Moderate
Varies
Moderate
No important uncertainty or variability
Probably favors the intervention
Moderate costs
Low
No included studies
Probably increased
Probably yes
Probably yes
1. Problem:
Is the problem (pressure injuries) a priority?
JUDGEMENT
No
Probably No
Probably Yes
Yes
Varies
Don’t Know
RESEARCH EVIDENCE
The problem of treating pressure injuries is a significant priority to healthcare. Treating pressure injuries to achieve healing is a priority to most individuals who experience a PI. In 2021, the Guideline Governance Group undertook a stakeholder survey on priority issues to address in the guideline. Receiving clinical guidance on biophysical agents as a category (e.g., electrical stimulation, laser treatment, ultrasound, negative pressure wound therapy, etc.) for treating pressure injuries (PIs) was rated as a high priority by clinicians (median ranking 5/5), people with or at risk of PIs and their informal carers (median ranking 4/5) and by industry representatives (median ranking 4/5). In an earlier survey conducted by the previous Guideline Governance Group in 2018 (Haesler, Pittman et al. 2022), 87.86% (297/338) of individuals with or at risk of PIs and 88.01% (602/684) of informal carers rated receiving information on how to help pressure injuries heal as important or very important.
2. Desirable Effects:
How substantial are the desirable anticipated effects?
JUDGEMENT
Trivial
Small
Moderate
Large
Varies
Don’t Know
RESEARCH EVIDENCE
| Outcome | Electrical stimulation |
No electrical stimulation | Difference | Relative effect |
|---|---|---|---|---|
| Time to healing | -- | -- | 19 more per 1,000 (from 9 more to 38 more) |
HR 1.06 (0.47 to 2.41) |
| Complete healing | 105/284 (36.9%) | 34/228 (14.9%) | 297 more healed PIs per 1,000 (from 207 more to 425 more) |
RR 1.99 (1.39 to 2.85 |
| Change in PI surface area (cm2) | -- | -- | Mean differences ranged from -0.90 cm2 to 10.37 cm2 | -- |
| Pain score | -- | -- | Between group change score –0.73 (–3.33 to 1.86) | -- |
Outcome 1: Time to complete PI healing
A meta-analysis (Arora, Harvey et al. 2020) from two RCTs (Griffin, Tooms et al. 1991, Adunsky, Ohry et al. 2005) provided evidence on the effectiveness of electrical stimulation in reducing the time taken for PIs to completely heal. There was a non-significant reduced time to complete PI healing; however, the evidence was very uncertain, and the difference might not be clinically significant. The certainty of evidence was downgraded due to risk of bias of the two studies, and the wide confidence interval (CI) that crossed the value between recommending and not recommending using electrical stimulation (Arora, Harvey et al. 2020).
Outcome 2: Complete PI healing
A meta-analysis(Arora, Harvey et al. 2020) of eleven RCTs (Asbjornsen, Hernaes et al. 1990, Feedar, Kloth et al. 1991, Griffin, Tooms et al. 1991, Wood, Evans et al. 1993, Houghton, Campbell et al. 2010, Franek, Kostur et al. 2011, Polak, Kloth et al. 2016, Polak, Taradaj et al. 2016, Polak, Kloth et al. 2017, Polak, Kucio et al. 2018, Adunsky, Ohry et al. 2005) provided evidence on the effectiveness of electrical stimulation for proportion of PIs completely healing versus sham/no electrical stimulation.** Regimens included high voltage pulsed galvanic current electrical stimulation, transcutaneous electrical nerve stimulation (TENS), high voltage pulsed current (HVPC) electrical stimulation and pulsed low intensity direct current electrical stimulation. The regimens used different intensities, frequencies and polarity patterns, and included both pulsed and direct currents. Sessions were generally one hour in duration and performed once a day, either daily, or 3-5 times/week. Electrical stimulation was used as an adjunct to standard wound care (e.g., debridement, infection management and moist wound healing). Trial durations ranged from 20 days to 8 weeks. The studies variably included older adults, individuals with spinal cord injuries (SCI) and individuals in medical or surgical wards. In most studies, the mean age of participants was over 60 years. None of the studies were conducted in neonates or children. Electrical stimulation was associated with a significantly high proportion of PIs achieving complete healing (36.9% versus 14.9%, relative risk [1.99, moderate effect size] confidence interval [CI] 1.39 to 2.85). This translates to 297 more per 1,000 PIs completely healing (from (207 more to 425 more) when electrical stimulation is added to a standard wound care regimen. There is moderate certainty in this result. The certainty was downgraded once for risk of bias because many of the studies had either high or unclear risk of bias for performance bias and selective reporting (Arora, Harvey et al. 2020).
Outcome 3: Change in PI surface area (cm2)
Evidence was compiled in a systematic review (Arora, Harvey et al. 2020) from 12 RCTs (Asbjornsen, Hernaes et al. 1990, Feedar, Kloth et al. 1991, Wood, Evans et al. 1993, Karba, Benko et al. 1995, Adegoke and Badmos 2001, Ahmad 2008, Franek, Kostur et al. 2011, Polak, Taradaj et al. 2016, Polak, Kloth et al. 2017, García-Pérez, García-Ríos et al. 2018, Polak, Kucio et al. 2018, Adunsky, Ohry et al. 2005) on the effectiveness of electrical stimulation for change in PI surface area versus sham/no electrical stimulation.** The studies were highly heterogeneous, likely due to multiple reasons (e.g., differences in the types of participants, length of intervention, duration of PIs and risks of bias) and the results were not suitable for pooling (Arora, Harvey et al. 2020). The mean difference in PI surface area ranged from -0.90 cm2 to 10.37 cm2 across the studies. However, there is very low certainty. The evidence was downgraded for risk of bias because most studies had either high or unclear risk of bias for selection and detection bias, was downgraded for inconsistency due to the heterogeneity and was downgraded for imprecision because most CIs crossed the value between recommending and not recommending treatment (Arora, Harvey et al. 2020).
Outcome 4: Pain score
One RCT (Garcia-Perez, Garcia-Rios et al. 2018) reported the pain experience of individuals with a PI treated with ES (n=9) compared to conventional treatment (n=8). The group treated with ES had small improvements in their pain scores while there was a very small worsening of pain for the conventional treatment group after 20 treatment sessions. It was unclear if either change score represents clinical significance. The between group change score was –0.73 (–3.33 to 1.86). There is low certainty in this result. The certainty was downgraded once for risk of bias due to high risk of performance and selection bias (Arora, Harvey et al. 2020) and downgraded twice due to a wide confidence interval that spans the value between between recommending and not recommending treatment.
** Devices and regimens are described in the data extraction tables. Product names may have changed.
3. Undesirable Effects:
How substantial are the undesirable anticipated effects?
JUDGEMENT
Trivial
Small
Moderate
Large
Varies
Don’t Know
RESEARCH EVIDENCE
A Cochrane review (Arora, Harvey et al. 2020) reported that evidence from 13 RCTs (n=602 participants) indicated that adverse events in cohorts treated with electrical stimulation included redness of the skin, itchy skin, dizziness and delusions, deterioration of the PI, limb amputation and occasionally death. The data was not appropriate for a quantitative analysis, and an effect size was not estimable. The evidence was of low certainty due to downgrading because of risk of bias and imprecision. It was unclear if the more severe adverse events were directly related to using electrical stimulation. However, electric burns have been reported (Arora, Harvey et al. 2020).
4. Overall certainty of evidence: What is the overall certainty of the evidence of effects?
JUDGEMENT
Very low
Low
Moderate
High
No included studies
RESEARCH EVIDENCE
| Outcome | Relative Importance | Certainty of Evidence |
|---|---|---|
| Time to complete healing | CRITICAL | VERY LOW |
| Complete healing | CRITICAL | MODERATE |
| Change in PI surface area (cm2) | CRITICAL | VERY LOW |
| Pain | CRITICAL | VERY LOW |
There is no core outcome set specific to pressure injury healing. To determine the relative importance of outcome measures, the GGG reviewed literature (Gottrup, Apelqvist et al. 2010, Augustin, Schmitt et al. 2014, Driver, Gould et al. 2017, Driver, Gould et al. 2019, Miranda, Deonizio et al. 2021, Raepsaet, Alves et al. 2023, Gupta, Goldstone et al. 2024, Zhang, Zhang et al. 2024) on PI and wound healing outcome measures and, in 2021, undertook a survey of stakeholders regarding their perspective on the importance of commonly reported wound healing outcomes. Based on the review and survey, the GGG prioritized consideration of the following five outcome measures of interest when evaluating evidence for interventions to support PI healing (see below). These clinical outcomes were supported by all surveyed stakeholder groups as critically important to making decisions about the evidence, and are wound agnostic (Gupta, Goldstone et al. 2024), frequently reported in PI research (Miranda, Deonizio et al. 2021), and relevant to both clinical practice and quality of life for individuals with a PI (Driver, Gould et al. 2017, Driver, Gould et al. 2019). The hierarchy of outcome measures was:
Outcome 1: Time to healing
Outcome 2: Complete healing (total/percent healed)
Outcome 3: Change in wound size (% change)
Outcome 4: Pain
Outcome 5: If infected at baseline, changes in signs and symptoms of infection
Certainty of evidence for outcome measures
Certainty of evidence for time to complete PI healing was very low. The certainty was downgraded once due to both studies having high risk of bias for two domains, and one study having unclear risk of bias for another three domains (Arora, Harvey et al. 2020). The evidence was downgraded twice for imprecision due to 95% CI overlaps the crossing value between recommending and not recommending treatment, as well as a small number of events and low number of participants (Arora, Harvey et al. 2020).
Certainty of evidence for complete PI healing was moderate. The certainty was downgraded once because a lot of the studies had either high or unclear risk of bias for performance bias and selective reporting (Arora, Harvey et al. 2020).
Certainty of evidence for change in PI surface area (cm2) very low. The certainty was downgraded because a lot of the studies had either high or unclear risk of bias for selection and detection bias (Arora, Harvey et al. 2020). Certainty was also downgraded due to substantial heterogeneity, likely due to multiple reasons (e.g., differences in the types of participants, length of intervention, duration of PIs and risks of bias), and was also downgraded for imprecision due to 95% CI overlaps the crossing value between recommending and not recommending treatment (Arora, Harvey et al. 2020).
Certainty of evidence for pain score was very low. The certainty was downgraded once for risk of bias due to high risk of performance and selection bias (Arora, Harvey et al. 2020) and downgraded twice due to a wide confidence interval that spans the value between between recommending and not recommending treatment.
5. Values:
Is there important uncertainty about or variability in how much people value the main outcomes?
JUDGEMENT
Important uncertainty or variability
Possibly important uncertainty or variability
Probably no important uncertainty or variability
No important uncertainty or variability
RESEARCH EVIDENCE
In a Delphi survey (Lechner, Coleman et al. 2022) that developed a core outcomes et for PI prevention trials, the outcome of PI occurrence was rated as being of critical important (score of 7-9) by all types of stakeholders (health professionals, people with or at risk of a PI and their informal carers, industry representatives and researchers). Greater than 90% of the 158 participants rated this outcome measure as critically important (Lechner, Coleman et al. 2022).
6. Balance of Effects:
Does the balance between desirable and undesirable effects favour the intervention or the comparison?
JUDGEMENT
Favors the comparison
Probably favors the comparison
Does not favor either the intervention or the comparison
Probably favors the intervention
Favors the intervention
Varies
Don’t know
RESEARCH EVIDENCE
The desirable effects are moderate and the undesirable effects vary and are unclear. However, the nature of the adverse events is general minor and resolved with cessation of treatment.
7. Resources Required:
How large are resource requirements (costs) of the intervention?
JUDGEMENT
Large costs
Moderate costs
Negligible costs and savings
Moderate savings
Large savings
Varies
Don’t know
RESEARCH EVIDENCE
One study reported that the cost of an ES device ranges from USD 80 to USD 750 (USD in 2011 (Mittmann, Chan et al. 2011). The Cochrane review (Arora, Harvey et al. 2020) noted that electrical stimulation is costly, time-consuming to administer, and requires specialised equipment, training and daily application that is inconvenient for patients (Arora, Harvey et al. 2020). It also not accessible in many geographic and clinical settings.
8. Certainty of evidence of required resources:
What is the certainty of evidence of resource requirements (costs) of the intervention?
JUDGEMENT
Very low
Low
Moderate
High
No included studies
RESEARCH EVIDENCE
The Cochrane review (Arora, Harvey et al. 2020) noted the lack of adequate evidence on the resources required, noting the most comprehensive report is from 2011.
9. Cost Effectiveness: Does the cost-effectiveness of the intervention favour the intervention or the comparison?
JUDGEMENT
Favors the comparison
Probably favors the comparison
Does not favor either the intervention or the comparison
Probably favors the intervention
Varies
No included studies
RESEARCH EVIDENCE
A Canadian Health Technology (Hao, Horton et al. 2023) report found no cost-effectiveness studies, and our searches also did not located cost effectiveness studies.
10. Inequity:
What would be the impact of recommending the intervention on health inequity?
JUDGEMENT
Reduced
Probably reduced
Probably no impact
Probably increased
Increased
Varies
Don’t know
RESEARCH EVIDENCE
There are many geographic and clinical settings without access to electrical stimulation devices or appropriately trained health professionals.
11. Acceptability:
Is the intervention acceptable to key stakeholders?
JUDGEMENT
No
Probably no
Probably yes
yes
Varies
Don’t know
RESEARCH EVIDENCE
A cross-sectional study (Orr, Houghton et al. 2020) reported that knowledge scores regarding the use of electrical stimulation therapy of multidisciplinary health care providers (n=87, primarily registered nurses and physiotherapists working hospital environments in Canada) improved after participation in a customized online education program followed by a hands-on workshop. Before attending intensive training, 83.1% agreed they needed practical training before they could use electrical stimulation and 62.7% agreed they required training. Greater than 50% were neutral toward therapy costs and the potential benefits. These attitudes became more positive after attending the training program.
Individual consumers with lived experience of PIs reported that they had not been offered electrical stimulation in their clinical and geographic settings.
12. Feasibility:
Is the intervention feasible to implement?
JUDGEMENT
No
Probably no
Probably yes
yes
Varies
Don’t know
RESEARCH EVIDENCE
The cost of devices and the health system resources required to administered electrical stimulation in addition to standard wound care is likely to limited access in many geographic and cultural settings. However, a study has demonstrated that when accessible, electrical stimulation can be effectively delivered in community and home settings by individuals with PIs or their carers, without the direct oversight of health professionals (Houghton, Campbell et al. 2010). In this study, electrical stimulation was applied for 5 hours/day, usually overnight (Houghton, Campbell et al. 2010).
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