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At least 145 records · Page 8Linked to original sources

PubMed1996

Polyurethane versus silicone for endoprosthetic replacement of the metacarpophalangeal joints in rheumatoid arthritis.

In a prospective study 12 patients with rheumatoid arthritis underwent arthroplasty of four metacarpophalangeal joints. Two different implant materials were randomly used in each hand, polyurethane (Pellethane) or silicone (Silastic). Eleven patients with 44 (21 silicone; 23 polyurethane) implants were re-examined 4.5 years (range 3-5) postoperatively. No difference was found between the implant materials regarding pain, stability of the joint or recurrence of the ulnar drift. The mean range of motion was 41 degrees (range 20 degrees-70 degrees) in the polyurethane joints compared with 42 degrees (range 15 degrees-90 degrees) in the silicone joints. The extension deficit was more pronounced in the silicone (mean 11.4 degrees) than in the polyurethane (mean 5.8 degrees) joints, and clinical signs of synovitis around the implants were more common with the silicone arthroplasties. Radiographic analysis, performed with conventional radiography and computed tomography (CT) showed one implant fracture in each group. There was a more pronounced bone resorption around silicone implants, but more sclerosis around polyurethane implants. Bony spurs interfering with function of the implant were common with both materials.

Aged↗

PubMed2000

[Randomized prospective study to compare the efficiency between standard plastic and polyurethane stents in biliary tract malignant obstruction].

UNLABELLED: The aim of this paper is to compare the efficiency between standard plastic stents and polyurethane stents used in biliary tract malignant obstruction. The main problem of the plastic prosthesis is their early occlusion. On the other hand there is the hypothesis that due to the less porousness of the polyurethane surface, there might be lesser adherence and consequently a late occlusion. Thirty-eight patients in two groups of 19 were evaluated prospectively and at random in the Jerusalem Hadassah Hospital and the HIGA San Martín La Plata. They had biliary tract obstruction due to inoperable tumors. Biliary endoprosthesis (plastic standard or polyurethane 10 French diameter) were placed, according to the randomization, after a previous staging with clinical examination, laboratory analysis and images. The follow-up with the same parameters was monthly done. Twelve of the 38 patients were female and 26 male; age average 62.73 (range 81-49). The stents were placed in 17 patients with biliary cancer, 14 pancreatic cancer, 2 papila cancer, 2 gallbladder cancer with bile duct invasion and 3 liver metastasis with biliary tract compression. The clinical and laboratory parameters in 36 patients at 30 days improved. On the contrary, 2 (1 plastic standard and 1 polyurethane stent) did not improve. There were 29 deaths due to the basic illness and not related to the endoscopic method. The mean obstruction occurred at 12.76 weeks (range 32-4) in the standard stents and 12.05 (range 24-2) in the polyurethane ones. CONCLUSION: There were no significant differences in the two groups patients.

Aged↗

PubMed2001

Hydrodynamic function of a biostable polyurethane flexible heart valve after six months in sheep.

Survival to six months for sheep with a non-biostable polyurethane mitral heart valve prosthesis has been reported previously, however, with surface degradation and accumulation of calcified fibrin/thrombus that impaired leaflet motion and compromised hydrodynamic function. Newly available biostable polyurethanes may overcome this problem. Six adult sheep with biostable polyurethane trileaflet heart valve prostheses of documented hydrodynamic performance, implanted in the mitral position, were allowed to survive for 6 months. Explanted valves were photographed, resubmitted to hydrodynamic function testing, and studied by light and electron microscopy. Explanted valves were structurally intact and differed little in appearance from their preimplant state. Hydrodynamic testing showed no deterioration in pressure gradient or energy losses compared with pre-implant values. Biostable polyurethanes demonstrated improved blood compatibility leaving leaflets flexible and valve function unimpaired. Biostable polyurethanes may thus improve prospects for prolonged function of synthetic heart valve prostheses.

Animals↗

PubMed2003

[Reconstruction of a cervical esophagus segment with an artificial prosthesis by use of a polyurethane stent covered with collagen-chitosan sponge in dogs].

OBJECTIVE: To repair esophageal defects with an artificial prosthesis composed of biodegradable materials and nonbiodegradable materials, which is gradually replaced by host tissue. METHODS: The artificial esophagus was a two-layer tube consisting of a chitosan-collagen sponge and an inner polyurethane stent with a diameter of 20 mm and a length of 50 mm. We used the artificial esophagus to replace 5 cm esophageal defects in group I (five dogs) and in group II (ten dogs), and nutritional support was given after operation. The inner polyurethane stent was removed after 2 weeks in group I and after 4 weeks in group II endoscopically and epithelization of the regenerated esophagus was observed by histologic examination and transmission electron microscope. RESULTS: In group I, the polyurethane stent was removed after 2 weeks, and partial regeneration of esophageal epithelial was observed; and constriction of the regenerated esophagus progressed and the dogs became unable to swallow after 4 weeks. In group II, the polyurethane stent was removed after 4 weeks, highly regenerated esophageal tissue successfully replaced the defect and complete epithelization of the regenerated esophagus was observed. After 12 weeks, complete regeneration of esophageal mucosa structures, including mucosal smooth muscle and mucosal glands and partial regeneration of esophageal muscle tissue were observed. CONCLUSION: Esophageal high-order structures can be regenerated and provided a temporary stent and support by polyurethane stent and an adequate three-dimensional structure for 4 weeks by collagen-chitosan sponge.

Absorbable Implants↗

PubMed2003

Polyurethanes and childhood asthma.

BACKGROUND: Asthma is the most common chronic disease of children. Its prevalence in affluent nations has steadily and dramatically increased in recent decades. Genetic and environmental factors play a role in development of atopy and asthma. Imbalance in the immune system favoring respiratory diseases has been linked to exposure to environmental stressors (e.g, biological and chemical) very early in life. Isocyanates, used in the production of polyurethane, can elicit asthma and produce immune responses (e.g, antibodies, cytokines, etc.) typical of atopy. MATERIAL/METHODS: Numerous medical materials that directly contact human neonates are constructed of polyurethanes. A detailed survey and listing of such materials was undertaken in the neonatal unit of a large urban hospital. Representative samples of polyurethane-containing materials were tested for isocyanate residues using a semi-quantitative colorimetric method. RESULTS: Isocyanate residues were detected in wound dressings, adhesive films, oximetry sensors, etc, that directly contact neonatal skin. CONCLUSIONS: Dermal exposure to polyurethane and, thus, to isocyanates could occur early in life through contact with medical materials. In an animal model, dermal exposure to isocyanates leads to dermal sensitization and asthma. We postulate that dermal contact with polyurethane-containing medical materials may be involved in dysregulation of the neonatal immune system and could predispose infants to the development of childhood asthma.

Animals↗

PubMed2005

[Effect of preparation conditions for small-diameter artificial polyurethane vascular graft on microstructure and mechanical properties].

OBJECTIVE: To study the effect of preparation conditions for small-diameter polyurethane(PU) vascular graft on microstructure and mechanical properties. METHODS: The small-diameter microporous PU artificial vascular grafts were prepared by dipping and leaching method. The dimension and microstructure were controlled by changing mold diameter, PU materials, salt sizes, salt to polymer ratio, times of dipping layers etc. The mechanical properties of PU grafts including radical compliance, water permeability, longitudinal strength, burst strength, and suture tearing strength were measured and the effect of the graft dimension and microstructure on their properties were studied. RESULTS: The internal diameter of grafts prepared was 2-4 mm depending on mold diameter. The wall thickness was 0.6-1.2 mm after dipping 4-8 layers. The density was 0.23-0.49 g/cm3. The pore was 42-95 microm in diameter. The porosity was 56%-80%. The radical compliance was 1.2%-7.4% x 13.3 kPa(-1) and higher compliances could be obtained by using more elastic polyurethane, higher salt to polymer ratio, longer diameter and less wall thickness. The water permeability, mainly depending on salt to polymer ratio, diameter, and wall thickness, was 0.29-12.44 g/(cm2 x min). The longitudinal strength was 1.55-4.36 MPa correlating with tensile strength of polyurethane and salt to polymer ratio. The burst strength was 60-300 kPa also depending on tensile strength of polyurethane and salt to polymer ratio. The suture tearing strength was 19.5-96.2 N/cm2 depending on tensile strength of polyurethane but not on the angle of tearing and graft axial directions. The compliance and water permeability of Chronoflex grafts were higher than those of PCU-1500 grafts, but longitudinal strength, burst strength, and suture tearing strength of PCU-1500 grafts were better than those of Chronoflex grafts. Conclusion Small-diameter grafts with proper pore sizes, porosity, matching compliance can be obtained by selecting PU materials and optimizing the preparation conditions.

Blood Vessel Prosthesis↗

PubMed1989

[Degradation of polyurethanes in aqueous environment].

The effect of in vitro exposure to aqueous environments on the change of properties of polyurethanes was studied as a model experiment for understanding the in vivo degradation of polyurethanes. Films of three commercially available medical polyurethanes consisting of diphenylmethane diisocyanate (MDI) (Biomer, Cardiothane and TM-3) and an experimental segmented polyurethane based on hydrogenated MDI (HMDI) were immersed in phosphate buffer or HEPES buffer containing lithium chloride at pH 7.4 at 70 degrees C for up to one year. Samples were subjected to ATR-FTIR measurement, tensile testing and viscosity measurement. Stability to hydrolytic degradation increased in the order: HMDI, TM-3, Biomer and Cardiothane. This ranking was consistent with that obtained in vivo. The results suggest that an in vitro model experiment is helpful for understanding and predicting degradation performance of polyurethanes in vivo.

Hydrolysis↗

PubMed1978

[Studies on orthodontic polyurethane ringlets. (Part 1) Examination of its physical properties (author's transl)].

The purpose of this study was to develop orthodontic ringlets from polyurethane which have maximum flow resistance. The two types of polyurethane involved were thermoplastic and thermosetting polyurethane. The former included Paraprene 22, 25, 4805 + 4806, Biomer, Elastollan 585 (E-585) and improved Elastollan 590 (E-590). Thermosetting type incorporated Adiprene, Loyler 2170, Colonate 4080 and DC-4978. Using these materials as its base, a ring device was developed. Under two conditions, tests were conducted for tensile strength, aging effects on 50% and 100% modulus and permanent elongation. One group was stored in air at 20 degrees C and the other in water at 37 degrees C. The results were as follows; It was found that the thermoplastic polyurethane possessed high tensile strength. However, the modulus upon aging resulted in a lower reading with the exception of E-590 and Biomer. In the thermosetting polyurethane group, most of the rings except DC-4978 broke down during storage at 100% elongation in water at 37 degrees C. In the case of DC-4978, there was maximum flow resistance. Upon comparing it with E-590 and Biomer, it appeared that DC-4978 was the most effective for orthodontic purposes.

Elasticity↗

PubMed1988

In vivo evaluations of a new thromboresistant polyurethane for artificial heart blood pumps.

To reduce the risk of thromboembolic complications in prosthetic blood pumps, we have developed a new segmented polyurethane elastomer. This material is unique because its mechanical properties for long-term durability and surface properties for biocompatibility have been separated and developed in two distinct materials. Improved thromboresistance is then obtained by a 1% concentration of a new polymeric surface-modifying additive blended with the base polyurethane before fabrication of the blood pump. To evaluate this material in vivo, we performed 10 implants, in calves, of the Pierce-Donachy prosthetic ventricle with blood-pumping sacs and cannulas fabricated from the new surface-modifying additive copolymer blend (Thoratec's BPS-215M). In four control implants the blood sacs and cannulas were fabricated from Ethicon's Biomer segmented polyurethane, which is the present clinical standard for most artificial hearts and circulatory support devices. The blood pumps were connected from the apex of the left ventricle to the descending aorta in male Holstein calves weighing 82 to 108 kg and were driven pneumatically in the full-to-empty mode with flows averaging 5 to 6 L/min. Each calf was medicated with aspirin and dipyridamole throughout the study period and was electively put to death after 4 weeks for evaluation of explanted blood sacs and for examination of the kidneys for infarction. All 10 explanted blood sacs made with the surface-modifying additive copolymer blend were shiny and completely free of thrombus. Three of the four explanted Biomer blood sacs showed visible red thrombus, and all four showed small areas of white thrombus. The average surface area of the Biomer blood sacs covered with thrombus was 45 +/- 32 mm2. Use of a semiquantitative scale to assess renal infarction demonstrated that nine of 10 animals with a surface-modifying additive copolymer blend blood sac had infarction less severe than the mean infarct score of the animals with a Biomer sac. The surface-modifying additive copolymer blend has excellent mechanical and physical properties necessary for use in artificial heart blood pumps. From these experiments, we conclude that the surface-modified polyurethane blend is superior to Biomer polyurethane in blood compatibility and in freedom from thromboembolic risk. This material is now approved by the Food and Drug Administration for investigational device exemption studies in the Pierce-Donachy prosthetic ventricle.

Animals↗

PubMed1978

Tissue reactions to breast implants coated with polyurethane.

The histological features noted in the capsules from 7 polyurethane coated silicone breast prostheses are described. The polyurethane provoked a definite foreign body reaction and was slowly degraded, with some particles ejected from the capsule into the surrounding tissues. Separation of the polyurethane coating from the silicone prosthesis and the degradation of the polyurethane took about two years. Another much more resistant foreign material was found to occur in conjunction with the polyurethane in the capsules. It may be an adhesive or flakes off the silicone shell. Vacuolated spaces were noted in the inner layers of 3 capsules; it was assumed that they contained liquid silicone.

Breast↗

PubMed1997

New antiinfectious biomaterials. Ciprofloxacin containing polyurethanes as potential drug delivery systems to prevent foreign-body infections.

Device related infections are an increasing problem since foreign materials are used in modern medicine. Ciprofloxacin-HCl salt (CAS 86393-32-0) and lipophilic ciprofloxacin-betaine (Bay o 9867) incorporated into polyurethanes by solvent casting technique were studied in order to develop antiinfectious properties of this biomaterial. Drug release rates, bacterial colonization and morphological features of the polymerciprofloxacin combinations were studied and the physico-chemical mechanisms of the delivery were discussed. Ciprofloxacin salt showed a fast initial release rate, whereas ciprofloxacin-betaine was characterized by a more continuous release behaviour. A higher diffusity of the lipophilic ciprofloxacin-betaine in the polymer could be shown as compared to its salt incorporated into the polyurethane. The high initial burst effect of the hydrochloride antibiotic was caused by its high solubility in the elution medium. Bacterial colonization to the antibiotic-loaded polyurethanes was inhibited effectively only by preparations showing a slower but more sustained drug release. Scanning electron microscopy (SEM) demonstrated that the polyurethane-antibiotic combination was most homogenous for ciprofloxacin-betaine. Polyurethane material loaded with ciprofloxacin salt showed crystals at the surface and a granular structure of the polymeric matrix. Crystalline structure of the drug on polymeric surfaces varied with loading concentration and lipophilicity. Physico-chemical similarity of the polymeric material and the antibodies is important for the homogeneity of the polymer-antibiotic combinations. High homogeneity is required for a sustained and prolonged release and effective inhibition of bacterial colonization.

Anti-Infective Agents↗

PubMed1998

Surface modification of polyurethane heart valves: effects on fatigue life and calcification.

Polyurethane heart valves can be functionally durable with minimal calcification, in vitro. In vivo, these characteristics will depend on the resistance of the polyurethane to thrombogenesis and biodegradation. Surface modification may improve the polyurethane in these respects, but may adversely affect calcification and durability. This study investigates the effects of surface modifications of two polyurethane heart valves (PEU and PEUE) on their in vitro fatigue and calcification behaviour. Modifications included heparin, taurine, 3-aminopropyltriethoxysilane and polyethylene oxide (PEO). Neither hydrodynamic function nor leaflet thickness distribution was significantly altered by surface modification. PEO-modification was detrimental to valve fatigue durability and calcification. Heparin, taurine or aminosilane modifications of PEU valves increased durability. Aminosilane modification of PEUE valves increased durability compared with PEO modification. Appropriate surface modification may be useful to improve blood compatibility of implantable polyurethanes, and may also be advantageous as regards fatigue durability of flexing materials in longterm applications.

Analysis of Variance↗

PubMed2006

Synthesis and in vitro biocompatibility of injectable polyurethane foam scaffolds.

The development of therapeutics for orthopedic clinical indications exploiting minimally invasive surgical techniques has substantial benefits, especially for treatment of fragility fractures in the distal radius of osteoporotics and vertebral compression fractures. We have designed six formulations of injectable polyurethane foams to address these clinical indications. The polyurethanes were prepared by mixing two liquid components and injecting the reactive liquid mixture into a mold where it hardens in situ. Porous polyurethane foams were synthesized from lysine methyl ester diisocyanate, a poly(epsilon-caprolactone-co-glycolide) triol, a tertiary amine catalyst, anionic and non-ionic stabilizers, and a fatty acid pore opener. The rise time of the foams varied from 8-20 min. The porosity was approximately 95% and the pores varied in size from 100-1000 microm. The polyurethane foams supported attachment of viable (>95%) MG-63 cells under dynamic seeding conditions. We anticipate compelling opportunities will be available as a consequence of the favorable biological and physical properties of the injectable polyurethane foams.

Animals↗

PubMed2006

[Structural study on the transparency of cross-linked polyester polyurethane].

The polyurethane material with cross-linked structure was synthesized using half pre-polymerization method. IR, UV-Vis, TEM and XRD methods, and physical properties measurements indicate that different moulding temperatures influence the apparent transparence of polyurethane and abrasive performance, and the nature of these changes is related to the conditions of processand chemical reaction which lead to gradual micro-phase separation of the polyurethane molecules with different compositions, resulting in the domain-forming with the size of sub-micro-, micro- and even more than ten micro-meters. Such domains aggregate one another to form particles with different shapes and complicated structures. The increase in the amount and size of these heterogeneous particles, distributed in the medium of transparent polyurethane, is the main cause that brings on an opaque appearance of polyurethane.

English Abstract↗

PubMed1998

Biocompatibility of polyurethane-coated stents: tissue and vascular aspects.

To assess the arterial injury triggered by polyurethane-coated vs. uncoated stents, six polyurethane-coated and six bare nitinol stents were implanted in rabbit carotid arteries. All animals were sacrificed 4 wk after stent placement. Sections were evaluated by histology and morphometric analysis. At 4 wk, both the coated and uncoated stent struts were entirely endothelialized. The spaces between the struts showed a relatively mild proliferative response, with a few sections demonstrating neovascularization around the struts. Polyurethane coating was associated with an inflammatory tissue response consisting of lymphocytic infiltration and foreign-body reaction, with the appearance of multinucleated giant cells. Lumen, intimal, and medial cross-sectional areas varied little between coated and uncoated stented vessels (2.45+/-0.19 vs. 2.47+/-0.47 mm2, 1.17+/-0.52 vs. 0.78+/-0.30 mm2, and 0.66+/-0.18 vs. 0.58+/-0.27 mm2, respectively). In the rabbit carotid artery model, polyurethane coating does not affect the degree of neointimal proliferation after endovascular stenting compared with the conventional stenting approach. However, the inflammatory tissue response may indicate a low intrinsic biocompatibility of this stable polymer, so that it may not be an ideal material for coating intravascular devices.

Animals↗

PubMed1999

Assessing the resistance to calcification of polyurethane membranes used in the manufacture of ventricles for a totally implantable artificial heart.

Ventricles made from segmented polyurethane membranes and used in the fabrication of a totally implantable artificial heart are known to undergo biomaterial-associated calcification. As there is no effective method currently available to prevent such biomaterials from calcifying, a practical solution is to use only materials with a relatively high resistance to calcification, to extend ventricular durability and ensure a longer functional life for the manufactured device. In the present study, an in vitro calcification protocol was used to determine the relative resistance to calcification of six different polyurethanes, namely, Carbothane PC3570A, Chronoflex AR, Corethane 80A, Corethane 55D, Tecoflex EG80A, and Tecothane TT1074A. The results demonstrated that all six polyurethanes did become calcified during the 60-day incubation period in the calcification solution. The degree of calcification was found to be associated with the surface chemistry of the particular polyurethane, with the Tecothane TT1074A exhibiting the highest level. The Corethane 80A and 55D polymers showed a relatively low propensity to calcify. These two membranes can, therefore, be considered as the most appropriate materials for the fabrication of ventricles for a totally implantable artificial heart. In addition, since the calcification occurred primarily at the surface of the membranes, without affecting the bulk microphase structure, the issue of modifying the surface chemistry to reduce the incidence of calcification is discussed.

Biocompatible Materials↗

PubMed1999

Photobinding of [gamma-(32)P] ATP gamma-benzophenone to the surface of a polyurethane membrane in the preparation of a beta-particle-emitting balloon catheter.

PURPOSE: The goal of this study was to photochemically bind 5'-[gamma-(32)P]-azido-ATP gamma-benzophenone ((32)P-ATP-BPA) to a polyurethane surface. Expandable balloon catheters composed of (32)P-coated polyurethane have the potential for preventing restenosis following percutaneous transluminal coronary angioplasty. METHODS: After extensive preparation and cleaning of polyurethane disks, 10 microL of the radioactive ATP-BPA reagent (specific activity = 9.4 Ci/mmol) was applied to the surface. After drying, the membrane disks were exposed ultraviolet radiation (254 nm; 6,000 microwatts/cm(2)) for up to 2 h and subsequently washed. The amount of (32)P bound to the membrane disks was determined by Cerenkov counting in a liquid scintillation counter. The effect of the labeling solution composition (solvent, presence of potassium or manganese ions, addition of surfactants, etc.) on photobinding efficiency was determined. RESULTS: The efficiency of attaching the (32)P-ATP-BPA reagent to the polyurethane surfaces was markedly dependent upon the cleaning and pretreatment conditions. Following detailed washing and rinsing steps, a photobinding efficiency of 36.4+/-3.6% was obtained with 10 min UV exposure time using (32)P-ATP-BPA solutions that were 95/5 methanol/water by vol. Increasing the concentration of the (32)P-ATP-BPA reagent did not improve the photobinding efficiency; however, the total amount of (32)P bound to the disks was increased. CONCLUSIONS: Photochemical methods can be employed to attach beta(-)-emitting radionuclides to polymers that are employed as balloon catheters. The preparation of the polymeric material (washing, rinsing, and drying) is critically important in maximizing the amount of (32)P-ATP-BPA that can be bound to the polymer.

Adenosine Triphosphate↗

PubMed2003

Gauze and tape and transparent polyurethane dressings for central venous catheters.

BACKGROUND: Central venous catheters facilitate venous access, allowing the intravenous administration of complex drug treatments, blood products and nutritional support, without the trauma associated with repeated venepuncture. However, central venous catheters are associated with a risk of infection. Some studies have indicated that the type of dressing used for central venous catheters may affect the risk of infection. Gauze and tape or transparent polyurethane film dressings such as Tegaderm, Opsite or Opsite IV3000 are the most common types of dressing used to secure central venous catheters. Currently, it is not clear which type of dressing is the most appropriate. OBJECTIVES: To compare gauze and tape and transparent polyurethane central venous catheter dressings in terms of catheter related infection, catheter security, tolerance to dressing material and dressing condition in hospitalised adults and children. SEARCH STRATEGY: The Cochrane Wounds Group Specialised Trials Register (October 2002), the Cochrane Controlled Trials Register (4th Quarter 2002) and the databases; MEDLINE (1966-December 2002, CINAHL (1982-October 2002) and EMBASE (1980-December 2002) were searched to identify any randomised controlled trials comparing the effects of gauze and tape and/or transparent polyurethane dressings for central venous catheter sites. Additional references were identified from bibliographies of published literature and were also sought from other sources. SELECTION CRITERIA: All randomised controlled trials evaluating the effects of dressing type (i.e. gauze and tape and/or transparent polyurethane dressings) on central venous catheter related infection, catheter security, tolerance to dressing material and dressing condition in hospitalised patients. DATA COLLECTION AND ANALYSIS: Twenty-three studies were reviewed. Data was extracted from each paper by two members of the review team independently and results then compared. Differences were resolved either by consensus or by referral to a third member of the review team. Authors were contacted for missing information. MAIN RESULTS: Of the 23 studies reviewed, 14 were excluded. Nine studies were included. Data was only available for meta-analysis from six of the nine included studies. Of the six included studies with available data, two compared gauze and tape with Opsite IV3000, two compared Opsite with Opsite IV3000, one compared gauze and tape with Tegaderm, and one compared Tegaderm with Opsite. There was no evidence of any difference in the incidence of infectious complications between any of the dressing types compared in this review. Each of these comparisons was based on no more than two studies and all of these studies reported data from a small patient sample. Therefore it is probable that the finding of no difference between dressing types is due to the lack of adequate data. REVIEWER'S CONCLUSIONS: There is a high level of uncertainty regarding the risk of infection with the central venous catheter dressings identified in this review. Therefore, at this stage it appears that the choice of dressing for central venous catheters can be based on patient preference. To identify the most appropriate central venous catheter dressings, further research is necessary. It is paramount that any future studies investigating this issue must be rigorously performed randomised controlled trials.

Bacterial Infections↗