Gill Norman (2020) — Negative pressure wound therapy for surgical wounds healing by primary closure

Negative Pressure Wound Therapy for Surgical Wounds Healing by Primary Closure

·Cochrane Database of Systematic Reviews·2020·144 citations·General

This Cochrane systematic review (3rd update, search to June 2019) pooled 44 RCTs and 7,447 participants to determine whether prophylactic NPWT reduces SSI and other complications in primarily closed surgical wounds. It also assessed cost-effectiveness across four surgical indications using five economic studies.

Study Snapshot

Design

Cochrane systematic review and meta-analysis

Setting: Acute care hospitals; North America, Europe, Australasia

Objective

Whether prophylactic NPWT reduces SSI and improves cost-effectiveness versus standard dressings in primarily closed surgical wounds.

Outcome(s)

Surgical site infection incidence at 30-day follow-up

Subjects

7,447 participants across 44 RCTs

NPWT (various systems including VAC, PICO, PREVENA)
Standard dressing (gauze or conventional dressing)

Inclusion

RCTs comparing NPWT to any wound dressing
Uninfected surgical wounds healing by primary closure
Participants of any age in any care setting

Exclusion

Skin graft, flap closure, or graft donor site wounds
Wounds healing by secondary or delayed primary intention
Cross-over trials and quasi-randomised studies

Follow-up

Primarily 30 days; some trials up to 6 months

Statistics

Random-effects meta-analysisRisk ratio with 95% CIGRADE certainty assessmentI² heterogeneity statistic

Key Findings

NPWT probably reduces SSI in primarily closed surgical wounds: 8.8% with NPWT vs 13.0% with standard dressings (RR 0.66, 95% CI 0.55–0.80; 31 trials, 6,204 participants). This is the strongest finding in the review — moderate-certainty evidence representing approximately 43 fewer infections per 1,000 patients treated.
NPWT does not clearly reduce mortality (2.3% vs 2.7%, RR 0.86) or wound dehiscence (5.3% vs 6.2%, RR 0.88). Both findings carry only low-certainty evidence with confidence intervals crossing 1.0. Do not use NPWT expecting to prevent the wound from opening.
Skin blisters are a possible harm: point estimate RR 2.64, but with a 95% CI of 0.65–10.68 and I² of 69%, this signal is very uncertain. Monitor for blistering but the evidence does not yet confirm a definitive causal relationship.
For lower limb fracture surgery, NPWT is probably not cost-effective at any willingness-to-pay threshold (moderate-certainty evidence from the WHIST trial, 1,549 participants). This is the most practice-relevant cost finding for orthopedic surgeons.
For caesarean section in obese women, NPWT is probably cost-effective (moderate-certainty evidence, Hyldig 2019a/b, 876 participants). Cost-effectiveness is indication-specific. Do not extrapolate one population's result to another.
No clear differences were found for reoperation (RR 1.04) or seroma (RR 0.72). Both are low-certainty with wide confidence intervals. NPWT's benefit in primarily closed wounds is essentially limited to SSI reduction based on current evidence.
Risk of bias was high or unclear in most trials. Only 8 of 44 studies were at low risk of bias across all three key domains (sequence generation, allocation concealment, detection bias), which is why even the primary SSI result was downgraded to moderate certainty.

Board PearlProphylactic NPWT reduces SSI from 13% to 8.8% in primarily closed wounds, but is not cost-effective for fracture surgery at any willingness-to-pay threshold.

Clinical Relevance

Prophylactic NPWT use in orthopedics has grown rapidly, but the evidence base has lagged behind adoption — prior reviews were inconclusive, many included non-randomized data, and none formally assessed cost-effectiveness.

The SSI reduction is real and moderate-certainty, but context matters: a 4 percentage point absolute risk reduction is meaningful only when baseline SSI risk is high enough to justify the added cost and complexity of NPWT.

For fracture surgery specifically, the WHIST trial (1,549 patients) found NPWT was not cost-effective at any willingness-to-pay threshold. This is your answer when a rep suggests routine prophylactic NPWT after ORIF.

Apply NPWT selectively based on baseline SSI risk, patient factors (obesity, diabetes, immunosuppression), and surgical indication. Obese patients undergoing high-risk closures may benefit most; routine use after standard fracture fixation is not supported by current evidence.

Emerging

Negative Pressure Wound Therapy for Surgical Wounds Healing by Primary Closure

Norman, Reid, et al.·Cochrane Database of Systematic Reviews·2020·144 citations·General

Negative Pressure Wound Therapy for Surgical Wounds Healing by Primary Closure

Study Snapshot

Key Findings

Clinical Relevance

Related Articles

Negative Pressure Wound Therapy for Surgical Wounds Healing by Primary Closure

Study Snapshot

Key Findings

Clinical Relevance

Related Articles

Negative Pressure Wound Therapy for Surgical Wounds Healing by Primary Closure

Study Snapshot

Key Findings

Clinical Relevance

Related Articles

Negative Pressure Wound Therapy for Surgical Wounds Healing by Primary Closure

Study Snapshot

Key Findings

Clinical Relevance

Related Articles