|Scalpel safety in the operative setting
|Watt A, Maddern G, Patkin M, Sinnott M, Black R
The review concluded that the paucity of evidence made it impossible to draw conclusions regarding the most effective or efficacious device or procedure for the prevention of scalpel injuries in the operative setting. The authors' cautious conclusions appear to reflect the poor-quality studies on this topic, but there remained a possibility of language and publication biases.
To assess the efficacy and effectiveness of devices and procedures aimed at lowering the incidence of scalpel injuries in the operative setting.
MEDLINE, EMBASE, CINAHL, The Cochrane Library, Current Contents and Australasian Medical Index (AMI) were searched without language restriction from inception to December 2006. Clinical Trials Database (US), NHS CRD database (UK), National Research Register (UK) and the Meta Register of Controlled Trials were searched to January 2007. Search terms were reported. Relevant journals were handsearched and the reference lists of retrieved publications were scanned for additional articles.
Eligible studies were systematic reviews, randomised controlled trials (RCTs), randomised comparative studies, non-randomised comparative studies, observational studies, survey and modelled data that evaluated any device or procedure aimed at reducing scalpel injuries in comparison with standard procedure. Studies of healthcare professionals exposed to scalpels in the operative setting were eligible for inclusion. The outcomes of interest were effectiveness, user satisfaction, failure, implications of use, cost and resource use of new devices or procedures.
Studies included in the review assessed cut-resistant gloves and glove liners (such as kevlar, spectra, polymer mesh, steel, cloth, thick latex), hands-free passing technique (HFPT), sharpless surgery, passing tray and single-handed scalpel blade removers compared to standard procedures. Outcomes assessed included perforation rates, puncture resistance, injuries and contaminations, sensory, motor function and user comfort. Settings included orthopaedic surgery, oral and maxillofacial surgery or were conducted in laboratory settings. Participants included were members of operative teams who undertook a variety of operations (details reported in review).
Studies in languages other than English were included only if the findings reported substantial additional data to that reported in well-designed English-language studies.
Two reviewers independently selected studies. Disagreements were resolved through discussion.
Assessment of study quality
Validity was assessed using methods derived from the Cochrane Collaboration and the CONSORT statement and assessed method of randomisation and allocation concealment, blinding of participants and outcome assessors, attempts to minimise bias, sample sizes, generalisability of results and statistical methods. The level of evidence was classified using the National Health and Medical Research Council (NHMRC) Hierarchy of Evidence (Level I derived from systematic reviews; Level II derived from at least one properly designed RCT; Level III-1 derived from well-designed pseudo-RCTs; Level III-2 derived from non-randomised comparative studies with concurrent control, cohort studies, case-control studies, or interrupted time-series with a control group; Level III-3 derived from comparative studies with historical control, two or more single arm studies, or interrupted time series without a parallel control; Level IV derived from case series, either post-test or pre-test/post-test).
The authors stated neither how the papers were assessed for validity nor how many reviewers performed the validity assessment.
It appeared that data on the occurrence of each outcome of interest were extracted from individual studies and used to calculate odds ratios and corresponding 95% confidence intervals (CI). Data were extracted using a standard form by one reviewer and checked for accuracy by a second reviewer.
Methods of synthesis
Data were grouped by the device and procedure examined, followed by composition of gloves. Where applicable, odds ratios from individual studies were combined using a fixed-effects model meta-analysis. Where heterogeneity was present, studies were combined using a narrative synthesis with each study described in the text and additional descriptive information placed in tables. Heterogeneity was assessed using the Χ2 test.
Results of the review
Nineteen studies were included in the review. Evidence levels were designated as Level II (seven studies), Level III-2 (three studies), Level III-3 (two studies) and Level IV (one study). Six studies were laboratory experiments and did not meet the NHMRC criteria. Reporting of randomisation was inadequate in five of seven randomised trials; two studies reported blinding and two studies reported losses to follow-up.
Cut-resistant gloves and glove liners (13 studies): For perforation of inner latex glove, two RCTs (n=476) found a significant benefit for the use of cloth gloves compared to double latex gloves (odds ratio 0.15; 95% CI: 0.08 to 0.28, p<0.00001). Lower rates of perforation were reported for intervention groups that used inner latex gloves (Kevlar, polymer mesh, steel, cloth, thick latex) compared to comparator groups that used conventional double latex gloves (eight studies). Statistical significance was reached for six studies.
For perforation of outer latex gloves, lower rates of perforation were found in groups that used outer latex gloves compared to conventional double latex gloves in three studies, but levels of significance were not reported. One study found no statistically significant differences between groups.
One study reported differences in the cut-resistant properties on a variety of gloves tested. Cloth gloves provided the least resistance. Steel gloves providing greatest resistance. One study reported statistically significant differences in terms of resistance for Kevlar, spectra and cotton cloth gloves compared to conventional double latex. No direct relationship between the thickness of gloves and puncture resistance was found in one study.
Hands-free passing technique (three studies): One study reported statistically significantly fewer incidences of contaminations or injuries for the use of hands-free passing technique compared to other techniques (p<0.05). No statistically significant differences were reported between groups for two further studies.
Sharpless surgery (one study): One study reported that 86.8% of procedures were completed successfully without reverting interoperatively to traditional sharps. There were no postoperative complications reported attributable to the use of sharpless techniques.
Passing tray and single-handed scalpel blade remover (one study): One study that used theoretical modelling suggested that using a pass tray and single-handed scalpel blade remover was potentially more effective in reducing injuries compared to a safety scalpel. The effectiveness of each method was dependent upon the activation rate of the device.
Protective footwear (one study): One study reported that each of 16 different types of shoes reduced the number of penetrations of the foot in comparison with the unshod control. Only six materials completely prevented penetration by sharp objects (suede sneaker, suede with inner mesh lining, leather with inner canvas lining; non-pliable leather; rubber with inner leather lining and new rubber). No other data was reported.
Other outcomes of sensory, motor functions and user comfort were reported.
It was not possible to draw any conclusions regarding the most effective or efficacious device or procedure for the prevention of scalpel injuries in the operative setting due to small sample sizes, different subgroups and heterogeneity of data presented.
Inclusion criteria were clearly defined for interventions, participants, outcomes and study design. Several relevant sources were searched, but no attempts were made to minimise publication bias. Publication bias was not formally assessed. No language restrictions were applied to the searches. But, authors included studies in languages other than English only if the findings reported substantial additional data to that reported in well-designed English-language studies, which potentially introduced bias into the selection of studies and data included. Methods were used to minimise reviewer errors and bias in the selection of studies and extraction of data, but it was unclear whether similar steps were taken in the assessment of validity. Validity was assessed, but the results were not fully reported, which made it difficult to independently comment on the reliability of the evidence presented. The methods used to combine studies appeared appropriate and statistical heterogeneity was assessed. The authors appropriately discussed the differences between the studies and the limitations of the evidence. The authors' cautious conclusions appear to reflect the poor-quality studies on this topic, but there remained a possibility of language and publication biases.
Implications of the review for practice and research
Practice: The authors stated that the concept of scalpel safety needed to be reinforced through education and practice in the operative setting to achieve a long-term reduction in scalpel injury rates.
Review: The authors stated that further research was needed to systematically assess the effectiveness of safety devices in reducing injury. In particular, large randomised controlled trials of cut-resistant gloves and glove liners were needed. Detailed audits of scalpel injuries were needed to put into context the incidence, prevalence and epidemiology of injuries within the Australian healthcare setting to allow targeting of interventions to operating procedures where large numbers of injuries occurred.
Australian Government Department of Health and Ageing; South Australian Department of Health.
Watt A, Maddern G, Patkin M, Sinnott M, Black R. Scalpel safety in the operative setting. Stepney, S. Australia, Australia: Royal Australasian College of Surgeons, Australian Safety and Efficacy Register of New Interventional Procedures (ASERNIP) - Surgical . ASERNIP-S Report; 59. 2007
Other publications of related interest
Watt AM, Patkin M, Sinnott MJ, Black RJ, Maddern GJ. Scalpel safety in the operative setting: a systematic review. Surgery 2010; 147(1): 98-106.
Subject indexing assigned by CRD
Humans; Operating Rooms /organization & administration; Safety Management; Surgical Instruments
Database entry date
This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.