Norman Gill, Goh En Lin, Dumville Jo C, Shi Chunhu, Liu Zhenmi, Chiverton Laura, Stankiewicz Monica, Reid Adam
Division of Nursing, Midwifery and Social Work, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK.
Oxford Trauma, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Oxford, UK.
Cochrane Database Syst Rev. 2020 May 1;5(5):CD009261. doi: 10.1002/14651858.CD009261.pub5.
Indications for the use of negative pressure wound therapy (NPWT) are broad and include prophylaxis for surgical site infections (SSIs). Existing evidence for the effectiveness of NPWT on postoperative wounds healing by primary closure remains uncertain.
To assess the effects of NPWT for preventing SSI in wounds healing through primary closure, and to assess the cost-effectiveness of NPWT in wounds healing through primary closure.
In June 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries and references of included studies, systematic reviews and health technology reports. There were no restrictions on language, publication date or study setting.
We included trials if they allocated participants to treatment randomly and compared NPWT with any other type of wound dressing, or compared one type of NPWT with another type of NPWT.
At least two review authors independently assessed trials using predetermined inclusion criteria. We carried out data extraction, assessment using the Cochrane 'Risk of bias' tool, and quality assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology.
In this third update, we added 15 new randomised controlled trials (RCTs) and three new economic studies, resulting in a total of 44 RCTs (7447 included participants) and five economic studies. Studies evaluated NPWT in the context of a wide range of surgeries including orthopaedic, obstetric, vascular and general procedures. Economic studies assessed NPWT in orthopaedic, obstetric and general surgical settings. All studies compared NPWT with standard dressings. Most studies had unclear or high risk of bias for at least one key domain. Primary outcomes Four studies (2107 participants) reported mortality. There is low-certainty evidence (downgraded twice for imprecision) showing no clear difference in the risk of death after surgery for people treated with NPWT (2.3%) compared with standard dressings (2.7%) (risk ratio (RR) 0.86; 95% confidence interval (CI) 0.50 to 1.47; I = 0%). Thirty-nine studies reported SSI; 31 of these (6204 participants), were included in meta-analysis. There is moderate-certainty evidence (downgraded once for risk of bias) that NPWT probably results in fewer SSI (8.8% of participants) than treatment with standard dressings (13.0% of participants) after surgery; RR 0.66 (95% CI 0.55 to 0.80 ; I = 23%). Eighteen studies reported dehiscence; 14 of these (3809 participants) were included in meta-analysis. There is low-certainty evidence (downgraded once for risk of bias and once for imprecision) showing no clear difference in the risk of dehiscence after surgery for NPWT (5.3% of participants) compared with standard dressings (6.2% of participants) (RR 0.88, 95% CI 0.69 to 1.13; I = 0%). Secondary outcomes There is low-certainty evidence showing no clear difference between NPWT and standard treatment for the outcomes of reoperation and incidence of seroma. For reoperation, the RR was 1.04 (95% CI 0.78 to 1.41; I = 13%; 12 trials; 3523 participants); for seroma, the RR was 0.72 (95% CI 0.50 to 1.05; I = 0%; seven trials; 729 participants). The effect of NPWT on occurrence of haematoma or skin blisters is uncertain (very low-certainty evidence); for haematoma, the RR was 0.67 (95% CI 0.28 to 1.59; I = 0%; nine trials; 1202 participants) and for blisters the RR was 2.64 (95% CI 0.65 to 10.68; I = 69%; seven trials; 796 participants). The overall effect of NPWT on pain is uncertain (very low-certainty evidence from seven trials (2218 participants) which reported disparate measures of pain); but moderate-certainty evidence suggests there is probably little difference between the groups in pain after three or six months following surgery for lower limb fracture (one trial, 1549 participants). There is also moderate-certainty evidence for women undergoing caesarean sections (one trial, 876 participants) and people having surgery for lower limb fractures (one trial, 1549 participants) that there is probably little difference in quality of life scores at 30 days or 3 or 6 months, respectively. Cost-effectiveness Five economic studies, based wholly or partially on trials included in our review, assessed the cost-effectiveness of NPWT compared with standard care. They considered NPWT in four indications: caesarean sections in obese women; surgery for lower limb fracture; knee/hip arthroplasty and coronary artery bypass graft surgery. They calculated quality-adjusted life-years for treatment groups and produced estimates of the treatments' relative cost-effectiveness. The reporting quality was good but the grade of the evidence varied from moderate to very low. There is moderate-certainty evidence that NPWT in surgery for lower limb fracture was not cost-effective at any threshold of willingness-to-pay and that NPWT is probably cost-effective in obese women undergoing caesarean section. Other studies found low or very low-certainty evidence indicating that NPWT may be cost-effective for the indications assessed.
AUTHORS' CONCLUSIONS: People experiencing primary wound closure of their surgical wound and treated prophylactically with NPWT following surgery probably experience fewer SSI than people treated with standard dressings (moderate-certainty evidence). There is no clear difference in number of deaths or wound dehiscence between people treated with NPWT and standard dressings (low-certainty evidence). There are also no clear differences in secondary outcomes where all evidence was low or very low-certainty. In caesarean section in obese women and surgery for lower limb fracture, there is probably little difference in quality of life scores (moderate-certainty evidence). Most evidence on pain is very low-certainty, but there is probably no difference in pain between NPWT and standard dressings after surgery for lower limb fracture (moderate-certainty evidence). Assessments of cost-effectiveness of NPWT produced differing results in different indications. There is a large number of ongoing studies, the results of which may change the findings of this review. Decisions about use of NPWT should take into account surgical indication and setting and consider evidence for all outcomes.
负压伤口治疗（NPWT）的应用指征广泛，包括预防手术部位感染（SSI）。NPWT对一期缝合术后伤口愈合有效性的现有证据仍不明确。
评估NPWT对一期缝合伤口预防SSI的效果，并评估NPWT在一期缝合伤口中的成本效益。
2019年6月，我们检索了Cochrane伤口专业注册库、Cochrane对照试验中心注册库（CENTRAL）、Ovid MEDLINE（包括在研及其他非索引引文）、Ovid Embase和EBSCO CINAHL Plus。我们还检索了临床试验注册库以及纳入研究的参考文献、系统评价和卫生技术报告。对语言、出版日期或研究背景没有限制。
如果试验将参与者随机分配至治疗组，并将NPWT与任何其他类型的伤口敷料进行比较，或将一种类型的NPWT与另一种类型的NPWT进行比较，我们将其纳入。
至少两名综述作者使用预先确定的纳入标准独立评估试验。我们进行了数据提取，使用Cochrane“偏倚风险”工具进行评估，并根据推荐分级、评估、制定与评价方法进行质量评估。
在本次第三次更新中，我们增加了15项新的随机对照试验（RCT）和三项新的经济学研究，共纳入44项RCT（7447名参与者）和五项经济学研究。研究评估了NPWT在包括骨科、产科、血管和普通手术等广泛手术中的应用。经济学研究评估了NPWT在骨科、产科和普通外科手术中的应用。所有研究均将NPWT与标准敷料进行比较。大多数研究在至少一个关键领域存在不明确或高偏倚风险。主要结局：四项研究（2107名参与者）报告了死亡率。低确定性证据（因不精确性下调两次）表明，接受NPWT治疗的患者术后死亡风险（2.3%）与接受标准敷料治疗的患者（2.7%）相比无明显差异（风险比（RR）0.86；95%置信区间（CI）0.50至1.47；I² = 0%）。39项研究报告了SSI；其中31项（620名参与者）纳入荟萃分析。中度确定性证据（因偏倚风险下调一次）表明，NPWT术后发生SSI的患者可能少于接受标准敷料治疗的患者（参与者的8.8%）；RR 0.66（95% CI 0.55至0.80；I² = 23%）。18项研究报告了伤口裂开；其中14项（3809名参与者）纳入荟萃分析。低确定性证据（因偏倚风险下调一次，因不精确性下调一次）表明，NPWT术后伤口裂开风险（参与者的5.3%）与标准敷料治疗（参与者的6.2%）相比无明显差异（RR 0.88，95% CI 0.69至1.13；I² = 0%）。次要结局：低确定性证据表明，NPWT与标准治疗在再次手术和血清肿发生率方面无明显差异。再次手术方面，RR为1.04（95% CI 0.78至1.41；I² = 13%；12项试验；3523名参与者）；血清肿方面，RR为0.72（95% CI 0.50至1.05；I² = 0%；七项试验；729名参与者）。NPWT对血肿或皮肤水泡发生的影响尚不确定（极低确定性证据）；血肿方面，RR为0.67（95% CI 0.28至1.59；I² = 0%；九项试验；1202名参与者），水泡方面，RR为2.64（95% CI 0.65至10.68；I² = 69%；七项试验；796名参与者）。NPWT对疼痛的总体影响尚不确定（来自七项试验（2218名参与者）的极低确定性证据，这些试验报告了不同的疼痛测量方法）；但中度确定性证据表明，下肢骨折术后三个月或六个月时，两组在疼痛方面可能差异不大（一项试验，1549名参与者）。对于接受剖宫产的女性（一项试验，876名参与者）和接受下肢骨折手术的患者（一项试验，1549名参与者），也有中度确定性证据表明，分别在30天、3个月或6个月时，生活质量评分可能差异不大。成本效益：五项经济学研究全部或部分基于我们综述中纳入的试验，评估了NPWT与标准护理相比的成本效益。他们考虑了NPWT在四个指征中的应用：肥胖女性剖宫产、下肢骨折手术、膝关节/髋关节置换术和冠状动脉搭桥手术。他们计算了治疗组的质量调整生命年，并对治疗的相对成本效益进行了估计。报告质量良好，但证据等级从中度到极低不等。中度确定性证据表明下肢骨折手术中NPWT在任何支付意愿阈值下均不具有成本效益，而NPWT在肥胖女性剖宫产中可能具有成本效益。其他研究发现低或极低确定性证据表明NPWT在所评估的指征中可能具有成本效益。
手术伤口一期缝合且术后预防性使用NPWT的患者，发生SSI的情况可能少于接受标准敷料治疗的患者（中度确定性证据）。接受NPWT治疗的患者与接受标准敷料治疗的患者在死亡人数或伤口裂开方面无明显差异（低确定性证据）。在所有证据为低或极低确定性的次要结局方面也无明显差异。在肥胖女性剖宫产和下肢骨折手术中，生活质量评分可能差异不大（中度确定性证据）。关于疼痛的大多数证据为极低确定性，但下肢骨折手术后NPWT与标准敷料在疼痛方面可能无差异（中度确定性证据）。NPWT成本效益评估在不同指征中产生了不同结果。有大量正在进行的研究，其结果可能会改变本综述的结果。关于NPWT的使用决策应考虑手术指征和背景，并考虑所有结局的证据。
