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Bioactive Materials Nov 2021Acute or degenerative meniscus tears are the most common knee lesions. Meniscectomy provides symptomatic relief and functional recovery only in the short- to mid-term... (Review)
Review
Acute or degenerative meniscus tears are the most common knee lesions. Meniscectomy provides symptomatic relief and functional recovery only in the short- to mid-term follow-up but significantly increases the risk of osteoarthritis. For this reason, preserving the meniscus is key, although it remains a challenge. Allograft transplants present many disadvantages, so during the last 20 years preclinical and clinical research focused on developing and investigating meniscal scaffolds. The aim of this systematic review was to collect and evaluate all the available evidence on biosynthetic scaffolds for meniscus regeneration both and in clinical studies. Three databases were searched: 46 preclinical studies and 30 clinical ones were found. Sixteen natural, 15 synthetic, and 15 hybrid scaffolds were studied . Among them, only 2 were translated into clinic: the Collagen Meniscus Implant, used in 11 studies, and the polyurethane-based scaffold Actifit®, applied in 19 studies. Although positive outcomes were described in the short- to mid-term, the number of concurrent procedures and the lack of randomized trials are the major limitations of the available clinical literature. Few studies also combined the use of cells or growth factors, but these augmentation strategies have not been applied in the clinical practice yet. Current solutions offer a significant but incomplete clinical improvement, and the regeneration potential is still unsatisfactory. Building upon the overall positive results of these "old" technologies to address partial meniscal loss, further innovation is urgently needed in this field to provide patients better joint sparing treatment options.
PubMed: 33898878
DOI: 10.1016/j.bioactmat.2021.03.033 -
Polymers Oct 2021Layered double hydroxides (LDHs) have attracted interest as reinforcing fillers in elastomers due to their ease of synthesis and customisability. A systematic review was... (Review)
Review
Layered double hydroxides (LDHs) have attracted interest as reinforcing fillers in elastomers due to their ease of synthesis and customisability. A systematic review was performed on the effect of LDHs on the mechanical properties of elastomers using the Scopus database. Of the 61 articles relevant to the search criteria, the majority were published on polyurethane (PU) and nitrile butadiene rubber (NBR). Mg-Al LDH was used in most of the studies and Zn-Al LDH was used second most common. LDH can act as a reinforcing filler, typically increasing tensile strength even at low concentrations, so it could be used as an alternative to traditional reinforcing fillers for elastomers. LDH can also be made a functional filler by selecting the right metals and interlayer anions. It was found that Mg-Al LDH and Zn-Al LDH can both participate in crosslinking reactions and can replace MgO and ZnO, respectively. Less Zn ions are required for crosslinking when LDH is used than when ZnO is used, making LDH more environmentally friendly. Organic modification is usually required to improve compatibility with the elastomer matrix, especially in non-polar elastomers. It enables exfoliation of the LDH and intercalation of polymer chains into the LDH interlayer to occur. Organic modifiers can also be used to functionalise the LDH. Stearic acid used in crosslinking systems can be replaced by stearate anions from stearate-modified LDH.
PubMed: 34771273
DOI: 10.3390/polym13213716 -
The Journal of Trauma and Acute Care... Apr 2021Burns cause a huge economic burden to society, and the wounds can be very difficult to manage. Clinical experience suggests that amniotic membrane (AM) is an economical... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Burns cause a huge economic burden to society, and the wounds can be very difficult to manage. Clinical experience suggests that amniotic membrane (AM) is an economical and effective biological dressing for burns. However, few systematic reviews or meta-analyses have been published on such use. We aimed to evaluate the role of AM dressings in burn wounds.
METHODS
A systematic search of the PubMed, Cochrane, Embase, and Web of Science databases was conducted in March 2020. The search was conducted to identify randomized control trials that compared selected features of AM with those of other dressings, such as silver sulfadiazine, polyurethane membrane, and honey. For skin-grafted wounds, we compared AM-covered skin grafts and traditional staple-fixed skin grafts. Outcomes of interest for the efficacy analysis included wound infection, pain, itching, scarring, and healing time. The number of adverse events in each treatment group, the rate of withdrawal because of adverse effects, the cost of treatment, and patient acceptability were assessed for the feasibility analysis.
RESULTS
Eleven randomized controlled trials with 816 participants total were identified in our review. Amniotic membrane treatment was more effective than conventional methods, silver sulfadiazine, and polyurethane membrane in treating burn wounds, but AM appears to be less effective than honey. No reports of AM-related disease transmission or adverse reactions were described in the included articles.
CONCLUSION
Amniotic membrane has beneficial effects in treating burn wounds; however, the evidence needs to be strengthened by further robust randomized controlled trials.
LEVEL OF EVIDENCE
Systematic Review/Meta-analysis, level III.
Topics: Amnion; Biological Dressings; Burns; Humans
PubMed: 33284236
DOI: 10.1097/TA.0000000000003050 -
Clinical Nutrition ESPEN Apr 2023Peripheral parenteral nutrition (PPN) refers to the delivery of artificial nutrition via a peripheral intravenous cannula. As a nutritional intervention it remains... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Peripheral parenteral nutrition (PPN) refers to the delivery of artificial nutrition via a peripheral intravenous cannula. As a nutritional intervention it remains under-utilised in peri-operative care. This is despite purported advantages which includes avoiding the risks associated with central venous lines and preventing potential delays to the initiation of nutrition support. This systematic review and meta-analysis will detail the available evidence for PPN use in surgery.
METHODS
A comprehensive search of the EMBASE and Medline databases was undertaken to identify randomised control trials (RCTs) involving PPN use in surgical patients published until July 30th 2022. Three domains of PPN use were reviewed including: PPN compared to crystalloid intravenous fluids on nutritional and clinical outcomes; PPN compared to Central PN (CPN) on nutritional outcomes and complications; and strategies to prevent thrombophlebitis associated with PPN.
RESULTS
The meta-analysis included 8 studies which included 698 patients. Use of PPN led to reduced post-operative weight loss (% body weight change) with a mean difference of -1.45% (95% CI -2.9 to -0.01, p = 0.05). There was no statistically significant difference in terms of length of stay, infectious/non-infectious complications, surgical site infections or phlebitis. 42 RCTs were included in the systematic review. 14 RCTs compared PPN to crystalloid infusion. There was significant heterogeneity in the trial populations, interventions and measured outcomes. Most trials found that PPN may improve nitrogen balance and positively impact nutritional markers. Quality of life and post-operative complications were either improved or no difference found in trials assessing these outcomes. Four RCTs showed that PPN is a safe and feasible alternative to CPN. 22 RCTs reported on measures that may impact on thrombophlebitis rates associated with PPN. These included lower osmolality of PPN solution, cyclical PPN delivery, use of a small gauge polyurethane cannula in an upper limb vein, addition of heparin/hydrocortisone to PPN solutions and placement of a GTN patch over infusion sites.
CONCLUSION
PPN is a safe and effective mode of delivery of peri-operative nutrition. It is a feasible short-term alternative to central-line delivered PN. There are a number of strategies to reduce thrombophlebitis associated with PPN use. Further high-quality RCTs are required to assess the use of PPN in contemporary surgical practice.
Topics: Humans; Parenteral Nutrition; Nutritional Support; Parenteral Nutrition Solutions; Thrombophlebitis; Nutritional Status
PubMed: 36963880
DOI: 10.1016/j.clnesp.2023.02.004 -
Dimensions of Critical Care Nursing :... 2020Hemodynamic monitoring, implemented by the placement of peripheral arterial catheters (PACs), is a characterizing aspect of the intensive care units. Peripheral arterial...
BACKGROUND
Hemodynamic monitoring, implemented by the placement of peripheral arterial catheters (PACs), is a characterizing aspect of the intensive care units. Peripheral arterial catheters can continually detect blood pressure and quickly conduct blood sampling. The use of PACs is generally considered safe, without serious complications. Currently, only 25% of the implanted catheters are actually subject to complications, including accidental removal, dislocation, occlusion, and infection. All of these complications arise from inadequate catheter stabilization at the level of the skin. This study aimed to summarize and describe the effectiveness and characteristics of dressings and securement devices for catheter stabilization.
METHODS
A systematic review of literature from the following databases was conducted: MEDLINE, CINAHL, Cochrane, EMBASE, and OvidSP. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement to guide article selection and reporting.
RESULTS
Herein 626 articles were referred, with 5 directly related to the topic under discussion. We found 3 studies that describe PAC failure and 4 about dislodgement. We described 6 types of dressings or securement devices and classified them into 3 categories for classifying PAC dressings or securement devices. These were detected and grouped as adhesive tissues, sutureless devices, and transparent polyurethane dressings.
CONCLUSIONS
Current research indicates that transparent polyurethane dressings offer the most effective catheter stabilization, but adhesive tissues may constitute a valid alternative. However, there are limited high-quality studies about effective dressings and securement devices for PACs.
Topics: Bandages; Catheterization, Peripheral; Catheters, Indwelling; Humans; Intensive Care Units; Polyurethanes
PubMed: 32740194
DOI: 10.1097/DCC.0000000000000433 -
Polymers Jul 2022Dressings made with polyurethanes have been found to exhibit good and varied biological properties that make them good candidates for this application. However, as has... (Review)
Review
Dressings made with polyurethanes have been found to exhibit good and varied biological properties that make them good candidates for this application. However, as has been seen, the wound-healing process is complex, which includes four different stages. So far, the design and evaluation of polyurethane for wound dressing has focused on achieving good properties (mechanical, physicochemical, and biological), but each of them separates from the others or even directed at only one of the stages of skin wound-healing. Therefore, the aim of this systematic review is to explore the applications of polyurethanes in wound dressings and to determine whether could be designed to cover more than one stage of skin wound-healing. The PRISMA guidelines were followed. The current research in this field does not consider each stage separately, and the design of polyurethane dressings is focused on covering all the stages of wound healing with a single material but is necessary to replace polyurethanes in short periods of time. Additionally, little emphasis is placed on the hemostasis stage and further characterization of polyurethanes is still needed to correlate mechanical and physicochemical properties with biological properties at each stage of the wound-healing. Current research demonstrates an effort to characterize the materials physiochemically and mechanically, but in terms of their biological properties, most of the literature is based on the performance of histological tests of explants morphologically probing the compromised tissues, which give an indication of the potential use of polyurethanes in the generation of wound-healing dressings.
PubMed: 35893955
DOI: 10.3390/polym14152990 -
The Journal of Vascular Access Jan 2024Short peripheral catheters (SPCs) are used to provide intravenous therapies in hospitalized patients. Recently, the category of SPC has become more complex, with the...
BACKGROUND
Short peripheral catheters (SPCs) are used to provide intravenous therapies in hospitalized patients. Recently, the category of SPC has become more complex, with the introduction in clinical practice of "integrated" SPCs (ISPCs), renewed regarding the material (polyurethane rather than polytetrafluoroethylene) and design (large wing; pre-assembled extension; preassembled needle-free connector (NFC)).
METHODS
This systematic review and meta-analysis aimed to analyze randomized controlled trials (RCTs) and quasi-randomized studies in hospitalized patients, analyzing the risk of overall catheter failure as well as the risk of each type of complication (occlusion, infiltration, thrombophlebitis, and dislodgement) for ISPCs compared to non-integrated SPCs. These systematic review and meta-analysis were registered on PROSPERO (CRD42022322970).
DATA SOURCES
We searched PUBMED, EMBASE, and the Cochrane Controlled Clinical Trials register from April to November 2022.
RESULTS: INCLUDED STUDIES
The research identified 1260 articles. After the abstract review, 13 studies were included for full manuscript review and, after that, six papers (4727 patients) were included in the meta-analysis.
DESCRIPTION OF THE EFFECT
We found a significantly reduced risk of catheter failure (pooling all complications) for ISPCs compared to SPCs ( = 0.002 RR 0.65; 95% CI 0.63-0.9). A significant reduction in the risks of occlusion ( = 0.007 RR 0.72; 95% CI 0.56-0.92) was observed. As regards the risk of infiltration, thrombophlebitis, and dislodgement, the analysis showed a trend in favor of ISPCs, though not statistically significant (respectively = 0.2 RR 0.84; 95% CI 0.64-1.1; = 0.25 RR 0.91; 95% CI 0.78-1.07; = 0.06 RR 0.72; 95% CI 0.52-1.01).
CONCLUSIONS
ISPCs significantly reduce the risks of catheter failure (overall complications) and occlusion. More RCTs are needed to understand if the preassembled ISPC is better than the composted closed system (non-integrated SPC + extension line + NFC).
PubMed: 38166435
DOI: 10.1177/11297298231218468 -
Aesthetic Plastic Surgery Feb 2020Implementation of polyurethane-covered (PU) implants into practice requires a reassessment of the experience and a learning curve period. Occasional publications...
BACKGROUND
Implementation of polyurethane-covered (PU) implants into practice requires a reassessment of the experience and a learning curve period. Occasional publications describe a few difficulties in this regard. However, there are no publications covering the spectrum of errors. The absence of definite information and contradictory findings makes the learning curve longer leading to many unsatisfactory results.
MATERIALS AND METHODS
The systematization is based on the 12 years of experience with over 1000 patients and previously published data. A literature review was conducted using PUBMED with the following keywords: polyurethane or foam or sponge and breast and implant. A total of 285 articles were found (last accessed 08/13/2019). All articles concerning polyurethane implants were studied along with any articles found describing the surgical techniques applied to them. Additional references found in the above-mentioned articles were also included in the study.
RESULTS
All errors can be divided into planning errors, errors in pocket development and surface-dependent errors, for which the polyurethane surface is the main reason. Surface-dependent errors include the errors connected to positioning and biointegration. The possible causes of late seroma with PU implants are discussed.
CONCLUSIONS
The polyurethane surface should not be considered textured in the clinical point of view. Previous experience with non-PU implants cannot be transferred to PU implants. The learning curve is unavoidable. The systematization of errors with PU implants facilitates a decision-making process during the primary and secondary surgery and lowers the risk of the unsatisfactory results.
LEVEL OF EVIDENCE IV
This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266.
Topics: Breast Implantation; Breast Implants; Humans; Mammaplasty; Polyurethanes; Prosthesis Design
PubMed: 31591671
DOI: 10.1007/s00266-019-01510-6 -
The Cochrane Database of Systematic... Feb 2021Extracranial carotid artery stenosis is the major cause of stroke, which can lead to disability and mortality. Carotid endarterectomy (CEA) with carotid patch... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Extracranial carotid artery stenosis is the major cause of stroke, which can lead to disability and mortality. Carotid endarterectomy (CEA) with carotid patch angioplasty is the most popular technique for reducing the risk of stroke. Patch material may be made from an autologous vein, bovine pericardium, or synthetic material including polytetrafluoroethylene (PTFE), Dacron, polyurethane, and polyester. This is an update of a review that was first published in 1996 and was last updated in 2010.
OBJECTIVES
To assess the safety and efficacy of different types of patch materials used in carotid patch angioplasty. The primary hypothesis was that a synthetic material was associated with lower risk of patch rupture versus venous patches, but that venous patches were associated with lower risk of perioperative stroke and early or late infection, or both.
SEARCH METHODS
We searched the Cochrane Stroke Group trials register (last searched 25 May 2020); the Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 4), in the Cochrane Library; MEDLINE (1966 to 25 May 2020); Embase (1980 to 25 May 2020); the Index to Scientific and Technical Proceedings (1980 to 2019); the Web of Science Core Collection; ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) portal. We handsearched relevant journals and conference proceedings, checked reference lists, and contacted experts in the field.
SELECTION CRITERIA
Randomised and quasi-randomised trials (RCTs) comparing one type of carotid patch with another for CEA.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed eligibility, risk of bias, and trial quality; extracted data; and determined the quality of evidence using the GRADE approach. Outcomes, for example, perioperative ipsilateral stroke and long-term ipsilateral stroke (at least one year), were collected and analysed.
MAIN RESULTS
We included 14 trials involving a total of 2278 CEAs with patch closure operations: seven trials compared vein closure with PTFE closure, five compared Dacron grafts with other synthetic materials, and two compared bovine pericardium with other synthetic materials. In most trials, a patient could be randomised twice and could have each carotid artery randomised to different treatment groups. Synthetic patch compared with vein patch angioplasty Vein patch may have little to no difference in effect on perioperative ipsilateral stroke between synthetic versus vein materials, but the evidence is very uncertain (odds ratio (OR) 2.05, 95% confidence interval (CI) 0.66 to 6.38; 5 studies, 797 participants; very low-quality evidence). Vein patch may have little to no difference in effect on long-term ipsilateral stroke between synthetic versus vein materials, but the evidence is very uncertain (OR 1.45, 95% CI 0.69 to 3.07; P = 0.33; 4 studies, 776 participants; very low-quality evidence). Vein patch may increase pseudoaneurysm formation when compared with synthetic patch, but the evidence is very uncertain (OR 0.09, 95% CI 0.02 to 0.49; 4 studies, 776 participants; very low-quality evidence). However, the numbers involved were small. Dacron patch compared with other synthetic patch angioplasty Dacron versus PTFE patch materials PTFE patch may reduce the risk of perioperative ipsilateral stroke (OR 3.35, 95% CI 0.19 to 59.06; 2 studies, 400 participants; very low-quality evidence). PTFE patch may reduce the risk of long-term ipsilateral stroke (OR 1.52, 95% CI 0.25 to 9.27; 1 study, 200 participants; very low-quality evidence). Dacron may result in an increase in perioperative combined stroke and transient ischaemic attack (TIA) (OR 4.41 95% CI 1.20 to 16.14; 1 study, 200 participants; low-quality evidence) when compared with PTFE. Early arterial re-stenosis or occlusion (within 30 days) was also higher for Dacron patches. During follow-up for longer than one year, more 'any strokes' (OR 10.58, 95% CI 1.34 to 83.43; 2 studies, 304 participants; low-quality evidence) and stroke/death (OR 6.06, 95% CI 1.31 to 28.07; 1 study, 200 participants; low-quality evidence) were reported with Dacron patch closure, although numbers of outcome events were small. Dacron patch may increase the risk of re-stenosis when compared with other synthetic materials (especially with PTFE), but the evidence is very uncertain (OR 3.73, 95% CI 0.71 to 19.65; 3 studies, 490 participants; low-quality evidence). Bovine pericardium patch compared with other synthetic patch angioplasty Bovine pericardium versus PTFE patch materials Evidence suggests that bovine pericardium patch results in a reduction in long-term ipsilateral stroke (OR 4.17, 95% CI 0.46 to 38.02; 1 study, 195 participants; low-quality evidence). Bovine pericardial patch may reduce the risk of perioperative fatal stroke, death, and infection compared to synthetic material (OR 5.16, 95% CI 0.24 to 108.83; 2 studies, 290 participants; low-quality evidence for PTFE, and low-quality evidence for Dacron; OR 4.39, 95% CI 0.48 to 39.95; 2 studies, 290 participants; low-quality evidence for PTFE, and low-quality evidence for Dacron; OR 7.30, 95% CI 0.37 to 143.16; 1 study, 195 participants; low-quality evidence, respectively), but the numbers of outcomes were small. The evidence is very uncertain about effects of the patch on infection outcomes.
AUTHORS' CONCLUSIONS
The number of outcome events is too small to allow conclusions, and more trial data are required to establish whether any differences do exist. Nevertheless, there is little to no difference in effect on perioperative and long-term ipsilateral stroke between vein and any synthetic patch material. Some evidence indicates that other synthetic patches (e.g. PTFE) may be superior to Dacron grafts in terms of perioperative stroke and TIA rates, and both early and late arterial re-stenosis and occlusion. Pseudoaneurysm formation may be more common after use of a vein patch than after use of a synthetic patch. Bovine pericardial patch, which is an acellular xenograft material, may reduce the risk of perioperative fatal stroke, death, and infection compared to other synthetic patches. Further large RCTs are required before definitive conclusions can be reached.
Topics: Aneurysm, False; Angioplasty; Bias; Bioprosthesis; Blood Vessel Prosthesis; Carotid Stenosis; Endarterectomy, Carotid; Humans; Polyethylene Terephthalates; Polytetrafluoroethylene; Postoperative Complications; Randomized Controlled Trials as Topic; Saphenous Vein; Stroke
PubMed: 33598915
DOI: 10.1002/14651858.CD000071.pub4 -
Annals of Work Exposures and Health Jul 2020Diisocyanates are a group of chemicals that are widely used in occupational settings. They are known to induce various health effects, including skin- and respiratory...
Diisocyanates are a group of chemicals that are widely used in occupational settings. They are known to induce various health effects, including skin- and respiratory tract sensitization resulting in allergic dermatitis and asthma. Exposure to diisocyanates has been studied in the past decades by using different types of biomonitoring markers and matrices. The aim of this review as part of the HBM4EU project was to assess: (i) which biomarkers and matrices have been used for biomonitoring diisocyanates and what are their strengths and limitations; (ii) what are (current) biomonitoring levels of the major diisocyanates (and metabolites) in workers; and (iii) to characterize potential research gaps. For this purpose we conducted a systematic literature search for the time period 2000-end 2018, thereby focussing on three types of diisocyanates which account for the vast majority of the total isocyanate market volume: hexamethylene diisocyanate (HDI), toluene diisocyanate (TDI), and 4,4'-methylenediphenyl diisocyanate (MDI). A total of 28 publications were identified which fulfilled the review inclusion criteria. The majority of these studies (93%) investigated the corresponding diamines in either urine or plasma, but adducts have also been investigated by several research groups. Studies on HDI were mostly in the motor vehicle repair industry [with urinary hexamethylene diamine result ranging from 0.03 to 146.5 µmol mol-1 creatinine]. For TDI, there is mostly data on foam production [results for urinary toluene diamine ranging from ~0.01 to 97 µmol mol-1 creatinine] whereas the available MDI data are mainly from the polyurethane industry (results for methylenediphenyl diamine range from 0.01 to 32.7 µmol mol-1 creatinine). About half of the studies published were prior to 2010 hence might not reflect current workplace exposure. There is large variability within and between studies and across sectors which could be potentially explained by several factors including worker or workplace variability, short half-lives of biomarkers, and differences in sampling strategies and analytical techniques. We identified several research gaps which could further be taken into account when studying diisocyanates biomonitoring levels: (i) the development of specific biomarkers is promising (e.g. to study oligomers of HDI which have been largely neglected to date) but needs more research before they can be widely applied, (ii) since analytical methods differ between studies a more uniform approach would make comparisons between studies easier, and (iii) dermal absorption seems a possible exposure route and needs to be further investigated. The use of MDI, TDI, and HDI has been recently proposed to be restricted in the European Union unless specific conditions for workers' training and risk management measures apply. This review has highlighted the need for a harmonized approach to establishing a baseline against which the success of the restriction can be evaluated.
Topics: Biological Monitoring; Humans; Occupational Exposure; Polyurethanes; Toluene 2,4-Diisocyanate; Workplace
PubMed: 32313948
DOI: 10.1093/annweh/wxaa038