Scolaris Content Display Scolaris Content Display

Study flow diagram.
Figuras y tablas -
Figure 1

Study flow diagram.

Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.
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Figure 2

Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.

Risk of bias summary: review authors' judgements about each risk of bias item for each included study.
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Figure 3

Risk of bias summary: review authors' judgements about each risk of bias item for each included study.

Forest plot of comparison: 1 NMES versus alternative prophylaxis, outcome: 1.1 Total DVT.
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Figure 4

Forest plot of comparison: 1 NMES versus alternative prophylaxis, outcome: 1.1 Total DVT.

Forest plot of comparison: 2 NMES versus no prophylaxis, outcome: 2.1 Total DVT.
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Figure 5

Forest plot of comparison: 2 NMES versus no prophylaxis, outcome: 2.1 Total DVT.

Comparison 1 NMES versus alternative prophylaxis, Outcome 1 Total DVT.
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Analysis 1.1

Comparison 1 NMES versus alternative prophylaxis, Outcome 1 Total DVT.

Comparison 1 NMES versus alternative prophylaxis, Outcome 2 Asymptomatic DVT.
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Analysis 1.2

Comparison 1 NMES versus alternative prophylaxis, Outcome 2 Asymptomatic DVT.

Comparison 1 NMES versus alternative prophylaxis, Outcome 3 Symptomatic DVT.
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Analysis 1.3

Comparison 1 NMES versus alternative prophylaxis, Outcome 3 Symptomatic DVT.

Comparison 1 NMES versus alternative prophylaxis, Outcome 4 PE.
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Analysis 1.4

Comparison 1 NMES versus alternative prophylaxis, Outcome 4 PE.

Comparison 1 NMES versus alternative prophylaxis, Outcome 5 Total VTE.
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Analysis 1.5

Comparison 1 NMES versus alternative prophylaxis, Outcome 5 Total VTE.

Comparison 2 NMES versus no prophylaxis, Outcome 1 Total DVT.
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Analysis 2.1

Comparison 2 NMES versus no prophylaxis, Outcome 1 Total DVT.

Comparison 2 NMES versus no prophylaxis, Outcome 2 Asymptomatic DVT.
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Analysis 2.2

Comparison 2 NMES versus no prophylaxis, Outcome 2 Asymptomatic DVT.

Comparison 2 NMES versus no prophylaxis, Outcome 3 Symptomatic DVT.
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Analysis 2.3

Comparison 2 NMES versus no prophylaxis, Outcome 3 Symptomatic DVT.

Comparison 2 NMES versus no prophylaxis, Outcome 4 PE.
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Analysis 2.4

Comparison 2 NMES versus no prophylaxis, Outcome 4 PE.

Comparison 2 NMES versus no prophylaxis, Outcome 5 Total VTE.
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Analysis 2.5

Comparison 2 NMES versus no prophylaxis, Outcome 5 Total VTE.

Comparison 3 NMES versus low‐dose heparin, Outcome 1 Total DVT.
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Analysis 3.1

Comparison 3 NMES versus low‐dose heparin, Outcome 1 Total DVT.

Comparison 3 NMES versus low‐dose heparin, Outcome 2 Asymptomatic DVT.
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Analysis 3.2

Comparison 3 NMES versus low‐dose heparin, Outcome 2 Asymptomatic DVT.

Comparison 3 NMES versus low‐dose heparin, Outcome 3 Symptomatic DVT.
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Analysis 3.3

Comparison 3 NMES versus low‐dose heparin, Outcome 3 Symptomatic DVT.

Comparison 4 NMES versus Dextran 40, Outcome 1 Total DVT.
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Analysis 4.1

Comparison 4 NMES versus Dextran 40, Outcome 1 Total DVT.

Comparison 4 NMES versus Dextran 40, Outcome 2 PE.
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Analysis 4.2

Comparison 4 NMES versus Dextran 40, Outcome 2 PE.

Comparison 4 NMES versus Dextran 40, Outcome 3 Total VTE.
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Analysis 4.3

Comparison 4 NMES versus Dextran 40, Outcome 3 Total VTE.

Comparison 5 Combined NMES and low‐dose heparin versus no prophylaxis, Outcome 1 Total DVT.
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Analysis 5.1

Comparison 5 Combined NMES and low‐dose heparin versus no prophylaxis, Outcome 1 Total DVT.

Comparison 6 Combined NMES and low‐dose heparin versus low‐dose heparin, Outcome 1 Total DVT.
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Analysis 6.1

Comparison 6 Combined NMES and low‐dose heparin versus low‐dose heparin, Outcome 1 Total DVT.

Comparison 7 NMES versus GCS, Outcome 1 Total DVT.
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Analysis 7.1

Comparison 7 NMES versus GCS, Outcome 1 Total DVT.

Comparison 7 NMES versus GCS, Outcome 2 PE.
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Analysis 7.2

Comparison 7 NMES versus GCS, Outcome 2 PE.

Comparison 8 NMES versus IPCD, Outcome 1 Total DVT.
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Analysis 8.1

Comparison 8 NMES versus IPCD, Outcome 1 Total DVT.

Comparison 8 NMES versus IPCD, Outcome 2 PE.
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Analysis 8.2

Comparison 8 NMES versus IPCD, Outcome 2 PE.

Summary of findings for the main comparison. NMES compared to alternative prophylaxis for the prevention of venous thromboembolism

NMES compared to alternative prophylaxis for the prevention of venous thromboembolism

Patient or population: participants at risk of venous thromboembolism
Setting: hospital, secondary care
Intervention: NMES
Comparison: alternative prophylaxis

Outcomes

Anticipated absolute effects* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Risk with alternative prophylaxis

Risk with NMES

Total DVT
Follow‐up: mean 11 days

Study population

OR 1.01
(0.60 to 1.70)

415
(6 RCTs)

⊕⊕⊝⊝
LOWa,b

170 per 1000

172 per 1000
(110 to 259)

Asymptomatic DVT
Follow‐up: 8 days

Study population

OR 1.61
(0.40 to 6.43)

89
(1 RCT)

⊕⊕⊝⊝
LOWa,c

82 per 1000

125 per 1000
(34 to 364)

Symptomatic DVT
Follow‐up: 8 days

Study population

OR 0.40
(0.02 to 10.07)

89
(1 RCT)

⊕⊕⊝⊝
LOWa,c

20 per 1000

8 per 1000
(0 to 173)

PE
Follow‐up: mean 4 days

Study population

OR 1.31
(0.38 to 4.48)

126
(2 RCTs)

⊕⊕⊝⊝
LOWa,c

70 per 1000

90 per 1000
(28 to 253)

Total VTE
Follow‐up: 6 days

Study population

OR 0.92
(0.34 to 2.52)

72
(1 RCT)

⊕⊕⊝⊝
LOWa,c

314 per 1000

297 per 1000
(135 to 536)

Bleeding (major and minor)

see comment

see comment

not estimable

415
(6 RCTs)

None of the studies in this comparison reported this outcome.

*Assumed control intervention risks were calculated by the mean number of events in control groups of selected studies for each outcome. The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: confidence interval; DVT: deep vein thrombosis; NMES: neuromuscular electrical stimulation; OR: odds ratio; PE: pulmonary embolism; RCT: randomised controlled trial; VTE: venous thromboembolism.

GRADE Working Group grades of evidence.
High quality: We are very confident that the true effect lies close to that of the estimate of the effect.
Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect.
Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect.

aHigh or unclear risk of selection bias, performance bias, and detection bias ‐ downgraded by one level.
bModerate level of between‐study heterogeneity ‐ downgraded by one level.
cFew participants and few events and thus wide confidence intervals ‐ downgraded by one level.

Figuras y tablas -
Summary of findings for the main comparison. NMES compared to alternative prophylaxis for the prevention of venous thromboembolism
Summary of findings 2. NMES compared to no prophylaxis for prevention of venous thromboembolism

NMES compared to no prophylaxis for prevention of venous thromboembolism

Patient or population: participants at risk of venous thromboembolism
Setting: hospital, secondary care
Intervention: NMES
Comparison: no prophylaxis

Outcomes

Anticipated absolute effects* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Risk with no prophylaxis

Risk with NMES

Total DVT
Follow‐up: mean 7 days

Study population

OR 0.40
(0.23 to 0.70)

576
(4 RCTs)

⊕⊕⊕⊝
MODERATEa

219 per 1000

101 per 1000
(61 to 164)

Asymptomatic DVT

Follow‐up: 7 days

Study population

OR 0.32
(0.06 to 1.62)

200
(1 RCT)

⊕⊕⊝⊝
LOWa,b

60 per 1000

20 per 1000
(4 to 94)

Symptomatic DVT

Follow‐up: 7 days

Study population

OR 0.06
(0.00 to 1.36)

160
(1 RCT)

⊕⊕⊝⊝
LOWa,b

50 per 1000

3 per 1000
(0 to 67)

PE

Follow‐up: 6 days

Study population

OR 0.36
(0.12 to 1.07)

77
(1 RCT)

⊕⊕⊝⊝
LOWa,b

350 per 1000

162 per 1000
(61 to 366)

Total VTE

Follow‐up: 6 days

Study population

OR 0.23
(0.09 to 0.59)

77
(1 RCT)

⊕⊕⊝⊝
LOWa,b

650 per 1000

299 per 1000
(143 to 523)

Bleeding (major and minor)

see comment

see comment

not estimable

576

(4 RCTs)

None of the studies in this comparison reported this outcome.

*Assumed control intervention risks were calculated by the mean number of events in control groups of selected studies for each outcome. The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: confidence interval; DVT: deep vein thrombosis; NMES: neuromuscular electrical stimulation; OR: odds ratio; PE: pulmonary embolism; RCT: randomised controlled trial; VTE: venous thromboembolism.

GRADE Working Group grades of evidence.
High quality: We are very confident that the true effect lies close to that of the estimate of the effect.
Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect.
Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect.

aHigh or unclear risk of selection bias, performance bias, and detection bias ‐ downgraded by one level.
bFew participants and few events and thus wide confidence intervals ‐ downgraded by one level.

Figuras y tablas -
Summary of findings 2. NMES compared to no prophylaxis for prevention of venous thromboembolism
Summary of findings 3. NMES compared to low‐dose heparin for the prevention of venous thromboembolism

NMES compared to low‐dose heparin for the prevention of venous thromboembolism

Patient or population: participants at risk of venous thromboembolism
Setting: hospital, secondary care
Intervention: NMES
Comparison: low‐dose heparin

Outcomes

Anticipated absolute effects* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Risk with low‐dose heparin

Risk with NMES

Total DVT
Follow‐up: mean 7 days

Study population

OR 2.78
(1.19 to 6.48)

194
(2 RCTs)

⊕⊕⊝⊝
LOWa,b

87 per 1000

208 per 1000
(101 to 380)

Asymptomatic DVT

Follow‐up: 8 days

Study population

OR 1.61
(0.40 to 6.43)

89
(1 RCT)

⊕⊕⊝⊝
LOWb,c

82 per 1000

125 per 1000
(34 to 364)

Symptomatic DVT

Follow‐up: 8 days

Study population

OR 0.40
(0.02 to 10.07)

89
(1 RCT)

⊕⊕⊝⊝
LOWb,c

20 per 1000

8 per 1000
(0 to 173)

PE

see comment

see comment

not estimable

194

(2 RCTs)

None of the studies in this comparison reported this outcome.

Total VTE

see comment

see comment

not estimable

194

(2 RCTs)

None of the studies in this comparison reported this outcome.

Bleeding (major and minor)

see comment

see comment

not estimable

194

(2 RCTs)

None of the studies in this comparison reported this outcome.

*Assumed control intervention risks were calculated by the mean number of events in control groups of selected studies for each outcome. The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: confidence interval; DVT: deep vein thrombosis; NMES: neuromuscular electrical stimulation; OR: odds ratio; PE: pulmonary embolism; RCT: randomised controlled trial; VTE: venous thromboembolism.

GRADE Working Group grades of evidence.
High quality: We are very confident that the true effect lies close to that of the estimate of the effect.
Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect.
Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect.

aHigh or unclear risk of selection bias, performance bias, and detection bias ‐ downgraded by one level.
bFew participants and few events and thus wide confidence intervals ‐ downgraded by one level.
cHigh or unclear risk of selection bias and detection bias ‐ downgraded by one level.

Figuras y tablas -
Summary of findings 3. NMES compared to low‐dose heparin for the prevention of venous thromboembolism
Summary of findings 4. NMES compared to Dextran 40 for the prevention of venous thromboembolism

NMES compared to Dextran 40 for the prevention of venous thromboembolism

Patient or population: participants at risk of venous thromboembolism
Setting: hospital, secondary care
Intervention: NMES
Comparison: Dextran 40

Outcomes

Anticipated absolute effects* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Risk with Dextran 40

Risk with NMES

Total DVT
Follow‐up: 6 days

Study population

OR 0.63
(0.18 to 2.19)

72
(1 RCT)

⊕⊕⊝⊝
LOWa,b

200 per 1000

136 per 1000
(43 to 354)

Asymptomatic DVT

see comment

see comment

not estimable

72

(1 RCT)

The single study in this comparison did not report this outcome.

Symptomatic DVT

see comment

see comment

not estimable

72

(1 RCT)

The single study in this comparison did not report this outcome.

PE

Follow‐up: 6 days

Study population

OR 1.50
(0.39 to 5.84)

72
(1 RCT)

⊕⊕⊝⊝
LOWa,b

114 per 1000

162 per 1000
(48 to 430)

Total VTE

Follow‐up: 6 days

Study population

OR 0.92
(0.34 to 2.52)

72
(1 RCT)

⊕⊕⊝⊝
LOWa,b

314 per 1000

297 per 1000
(135 to 536)

Bleeding (major and minor)

see comment

see comment

not estimable

72

(1 RCT)

The single study in this comparison did not report this outcome.

Assumed control intervention risks were calculated by the mean number of events in control groups of selected studies for each outcome. *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: confidence interval; DVT: deep vein thrombosis; NMES: neuromuscular electrical stimulation; OR: odds ratio; PE: pulmonary embolism; RCT: randomised controlled trial; VTE: venous thromboembolism.

GRADE Working Group grades of evidence.
High quality: We are very confident that the true effect lies close to that of the estimate of the effect.
Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect.
Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect,

aHigh or unclear risk of selection bias, performance bias, and detection bias ‐ downgraded by one level.
bSingle study, few participants, and few events and thus wide confidence intervals ‐ downgraded by one level.

Figuras y tablas -
Summary of findings 4. NMES compared to Dextran 40 for the prevention of venous thromboembolism
Summary of findings 5. Combined NMES and low‐dose heparin compared to no prophylaxis for the prevention of venous thromboembolism

Combined NMES and low‐dose heparin compared to no prophylaxis for the prevention of venous thromboembolism

Patient or population: participants at risk of venous thromboembolism
Setting: hospital, secondary care
Intervention: combined NMES and low‐dose heparin
Comparison: no prophylaxis

Outcomes

Anticipated absolute effects* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Risk with no prophylaxis

Risk with combined NMES and low‐dose heparin

Total DVT
Follow‐up: 28 days

Study population

OR 0.08
(0.01 to 0.76)

32
(1 RCT)

⊕⊕⊝⊝
LOWa,b

471 per 1000

66 per 1000
(9 to 403)

Asymptomatic DVT

see comment

see comment

not estimable

32

(1 RCT)

The single study in this comparison did not report this outcome.

Symptomatic DVT

see comment

see comment

not estimable

32

(1 RCT)

The single study in this comparison did not report this outcome.

PE

see comment

see comment

not estimable

32

(1 RCT)

The single study in this comparison did not report this outcome.

Total VTE

see comment

see comment

not estimable

32

(1 RCT)

The single study in this comparison did not report this outcome.

Bleeding (major and minor)

see comment

see comment

not estimable

32

(1 RCT)

The single study in this comparison did not report this outcome.

*Assumed control intervention risks were calculated by the mean number of events in control groups of selected studies for each outcome. The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: confidence interval; DVT: deep vein thrombosis; NMES: neuromuscular electrical stimulation; OR: odds ratio; PE: pulmonary embolism; RCT: randomised controlled trial; VTE: venous thromboembolism.

GRADE Working Group grades of evidence.
High quality: We are very confident that the true effect lies close to that of the estimate of the effect.
Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect.
Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect.

aHigh or unclear risk of selection bias and detection bias ‐ downgraded by one level.
bSingle study, few participants, and few events and thus wide confidence intervals ‐ downgraded by one level.

Figuras y tablas -
Summary of findings 5. Combined NMES and low‐dose heparin compared to no prophylaxis for the prevention of venous thromboembolism
Summary of findings 6. Combined NMES and low‐dose heparin compared to low‐dose heparin for the prevention of venous thromboembolism

Combined NMES and low‐dose heparin compared to low‐dose heparin for the prevention of venous thromboembolism

Patient or population: participants at risk of venous thromboembolism
Setting: hospital, secondary care
Intervention: combined NMES and low‐dose heparin
Comparison: low‐dose heparin

Outcomes

Anticipated absolute effects* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Risk with low‐dose heparin

Risk with combined NMES and low‐dose heparin

Total DVT
Follow‐up: 28 days

Study population

OR 0.07
(0.01 to 0.68)

31
(1 RCT)

⊕⊕⊝⊝
LOWa,b

500 per 1000

65 per 1000
(10 to 405)

Asymptomatic DVT

see comment

see comment

not estimable

31

(1 RCT)

The single study in this comparison did not report this outcome.

Symptomatic DVT

see comment

see comment

not estimable

31

(1 RCT)

The single study in this comparison did not report this outcome.

PE

see comment

see comment

not estimable

31

(1 RCT)

The single study in this comparison did not report this outcome.

Total VTE

see comment

see comment

not estimable

31

(1 RCT)

The single study in this comparison did not report this outcome.

Bleeding (major and minor)

see comment

see comment

not estimable

31

(1 RCT)

The single study in this comparison did not report this outcome.

*Assumed control intervention risks were calculated by the mean number of events in control groups of selected studies for each outcome. The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: confidence interval; DVT: deep vein thrombosis; NMES: neuromuscular electrical stimulation; OR: odds ratio; PE: pulmonary embolism; RCT: randomised controlled trial; VTE: venous thromboembolism.

GRADE Working Group grades of evidence.
High quality: We are very confident that the true effect lies close to that of the estimate of the effect.
Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect.
Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect.

aHigh or unclear risk of selection bias and detection bias ‐ downgraded by one level.
bSingle study, few participants, and few events and thus wide confidence intervals ‐ downgraded by one level.

Figuras y tablas -
Summary of findings 6. Combined NMES and low‐dose heparin compared to low‐dose heparin for the prevention of venous thromboembolism
Summary of findings 7. NMES compared to GCS for the prevention of venous thromboembolism

NMES compared to GCS for the prevention of venous thromboembolism

Patient or population: participants at risk of venous thromboembolism
Setting: hospital, secondary care
Intervention: NMES
Comparison: GCS

Outcomes

Anticipated absolute effects* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Risk with GCS

Risk with NMES

Total DVT
Follow‐up: 1 day

Study population

OR 0.32
(0.01 to 8.27)

36
(1 RCT)

⊕⊕⊝⊝
LOWa,b

56 per 1000

18 per 1000

(1 to 327)

Asymptomatic DVT

see comment

see comment

not estimable

36

(1 RCT)

None of the studies in this comparison reported this outcome.

Symptomatic DVT

see comment

see comment

not estimable

36

(1 RCT)

None of the studies in this comparison reported this outcome.

PE

Follow‐up: 1 day

Study population

OR 0.32
(0.01 to 8.27)

36
(1 RCT)

⊕⊕⊝⊝
LOWa,b

56 per 1000

18 per 1000
(1 to 327)

Total VTE

see comment

see comment

not estimable

36

(1 RCT)

None of the studies in this comparison reported this outcome.

Bleeding (major and minor)

see comment

see comment

not estimable

36

(1 RCT)

None of the studies in this comparison reported this outcome.

*Assumed control intervention risks were calculated by the mean number of events in control groups of selected studies for each outcome. The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: confidence interval; DVT: deep vein thrombosis; GCS: graduated compression stockings; NMES: neuromuscular electrical stimulation; OR: odds ratio; PE: pulmonary embolism; RCT: randomised controlled trial; VTE: venous thromboembolism.

GRADE Working Group grades of evidence.
High quality: We are very confident that the true effect lies close to that of the estimate of the effect.
Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect.
Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect.

aHigh or unclear risk of selection bias, performance bias, and detection bias ‐ downgraded by one level.
bSingle study, few participants, and few events and thus wide confidence intervals ‐ downgraded by one level.

Figuras y tablas -
Summary of findings 7. NMES compared to GCS for the prevention of venous thromboembolism
Summary of findings 8. NMES compared to IPCD for the prevention of venous thromboembolism

NMES compared to IPCD for the prevention of venous thromboembolism

Patient or population: participants at risk of venous thromboembolism
Setting: hospital, secondary care
Intervention: NMES
Comparison: IPCD

Outcomes

Anticipated absolute effects* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Risk with IPCD

Risk with NMES

Total DVT

Follow‐up: 1 day

Study population

not estimable

36
(1 RCT)

⊕⊕⊝⊝
LOWa,b

No DVT events were recorded.

see comment

see comment

Asymptomatic DVT

see comment

see comment

not estimable

36

(1 RCT)

None of the studies in this comparison reported this outcome.

Symptomatic DVT

see comment

see comment

not estimable

36

(1 RCT)

None of the studies in this comparison reported this outcome.

PE

Follow‐up: 1 day

Study population

not estimable

36
(1 RCT)

⊕⊕⊝⊝
LOWa,b

No PE events were recorded.

see comment

see comment

Total VTE

see comment

see comment

not estimable

36

(1 RCT)

None of the studies in this comparison reported this outcome.

Bleeding (major and minor)

see comment

see comment

not estimable

36

(1 RCT)

None of the studies in this comparison reported this outcome.

*Assumed control intervention risks were calculated by the mean number of events in control groups of selected studies for each outcome. The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: confidence interval; DVT: deep vein thrombosis; IPCD: intermittent pneumatic compression devices; NMES: neuromuscular electrical stimulation; OR: odds ratio; PE: pulmonary embolism; RCT: randomised controlled trial; VTE: venous thromboembolism.

GRADE Working Group grades of evidence.
High quality: We are very confident that the true effect lies close to that of the estimate of the effect.
Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect.
Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect.

aHigh or unclear risk of selection bias, performance bias, and detection bias ‐ downgraded by one level.
bSingle study, few participants, and few events ‐ downgraded by one level.

Figuras y tablas -
Summary of findings 8. NMES compared to IPCD for the prevention of venous thromboembolism
Table 1. Neuromuscular electrical stimulation delivery in the included studies

Study

Device

Frequency (Hz)

Pulse width

Charge (mA)

Voltage (V)

Duration

Hou 2013

G6805‐II

30‐100

NR

NR

6‐15

7 days

(20 minutes twice/d)

Goyal 2012

VEINOPLUS

NR

NR

NR

15–25

Only during surgery

Velmahos 2005

Lymphavision

1.75

3 ms

NR

0‐120

7‐14 days

(30 minutes twice/d)

Kiudelis 2002

Mioritm 021

NR

NR

50‐100

NR

Only during surgery

Merli 1988

NR

10

50 μs

NR

NR

28 days

(23 hours/d)

Bostrom 1986

NR

8

50 ms

40‐50

NR

7 days

Lindstrom 1982

NR

8

50 ms

40‐50

NR

Only during surgery

Rosenberg 1975

Thrombophylactor

NR

50 ms

NR

Adjustable

Only during surgery

NR: rot reported.

Figuras y tablas -
Table 1. Neuromuscular electrical stimulation delivery in the included studies
Comparison 1. NMES versus alternative prophylaxis

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Total DVT Show forest plot

6

415

Odds Ratio (M‐H, Fixed, 95% CI)

1.01 [0.60, 1.70]

2 Asymptomatic DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

3 Symptomatic DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

4 PE Show forest plot

2

126

Odds Ratio (M‐H, Fixed, 95% CI)

1.31 [0.38, 4.48]

5 Total VTE Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

Figuras y tablas -
Comparison 1. NMES versus alternative prophylaxis
Comparison 2. NMES versus no prophylaxis

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Total DVT Show forest plot

4

576

Odds Ratio (M‐H, Fixed, 95% CI)

0.40 [0.23, 0.70]

2 Asymptomatic DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

3 Symptomatic DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

4 PE Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

5 Total VTE Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

Figuras y tablas -
Comparison 2. NMES versus no prophylaxis
Comparison 3. NMES versus low‐dose heparin

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Total DVT Show forest plot

2

194

Odds Ratio (M‐H, Fixed, 95% CI)

2.78 [1.19, 6.48]

2 Asymptomatic DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

3 Symptomatic DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

Figuras y tablas -
Comparison 3. NMES versus low‐dose heparin
Comparison 4. NMES versus Dextran 40

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Total DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

2 PE Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

3 Total VTE Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

Figuras y tablas -
Comparison 4. NMES versus Dextran 40
Comparison 5. Combined NMES and low‐dose heparin versus no prophylaxis

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Total DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

Figuras y tablas -
Comparison 5. Combined NMES and low‐dose heparin versus no prophylaxis
Comparison 6. Combined NMES and low‐dose heparin versus low‐dose heparin

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Total DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

Figuras y tablas -
Comparison 6. Combined NMES and low‐dose heparin versus low‐dose heparin
Comparison 7. NMES versus GCS

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Total DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

2 PE Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

Figuras y tablas -
Comparison 7. NMES versus GCS
Comparison 8. NMES versus IPCD

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Total DVT Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

2 PE Show forest plot

1

Odds Ratio (M‐H, Fixed, 95% CI)

Totals not selected

Figuras y tablas -
Comparison 8. NMES versus IPCD