While several studies have shown that insulin pens are more convenient and accurate than conventional administration with syringes and vials (syringes/vials), there is a frequent need for low-dose insulin injections administered by nurses using syringes/vials in hospital settings, particularly for critically ill patients. However, there is a lack of research investigating factors related to the accuracy of low-dose insulin administration using syringes/vials, particularly in hospital settings. We therefore performed a cross-sectional study to assess the accuracy of low-dose insulin administration by registered nurses using syringes/vials and to determine whether time of day, years of experience and adherence to proper injection procedures (vertical insertion/drawing and air bubble checking) affected the accuracy. The participants were 33 registered nurses working in the diabetes ward, and a total of 198 trials were analyzed. Using syringes/vials, the median errors converted to insulin units were found to be 0.6 units for the 2- and 6-unit target doses, and 0.7 units for the 10-unit target dose. In cases with the largest error, errors for the 2-, 6-, and 10-unit target doses were observed to be 2.3, 4.0, and 3.3 units, respectively. In our study, time of day, years of experience and vertical insertion/drawing did not correlate with errors, but errors were significant in the participants who did not check for air bubbles. Nurses can make non-negligible dosage errors when administering low-dose insulin using syringes/vials, and this is particularly likely when air bubble checks are missed.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s13340-024-00726-5.

BACKGROUND: Anti-vascular endothelial growth factor (VEGF) agents have been the standard treatment for retinal diseases for almost two decades. These treatments are administered via intravitreal injection using single-use vials or prefilled syringes (PFS). In this systematic review, we evaluate health care resource use and clinical outcomes and experiences with PFS for intravitreal injection of anti-VEGF treatments.
METHODS: MEDLINE, EMBASE, and The Cochrane Library were searched from January 1, 2015 to February 8, 2024 to identify literature reporting outcomes regarding procedural efficiency, health care resource use, patient and clinician experiences, and safety for currently approved anti-VEGFs (ranibizumab, aflibercept, brolucizumab) administered using PFS. Comparators were vial-based injections of the same anti-VEGFs.
RESULTS: A total of 36 publications met the criteria for inclusion in the systematic literature review; the majority were non-randomized studies, with a small number of reviews, case series, survey studies, and opinion articles. Publications reported that preparation times were significantly shorter for PFS (40.3-57.9 s) versus vials (ranibizumab, 62.8-98.0 s; aflibercept, 71.9-79.5 s), with no differences in product stability between PFS and vials. Clinicians expressed a preference for PFS and thought PFS were faster, easier to use, and had increased safety versus vials. Publications consistently reported significantly lower rates of endophthalmitis per injection with PFS versus vials (ranibizumab PFS, 0-0.02%; aflibercept PFS, 0.01-0.02%; ranibizumab vial, 0.02-0.05%; aflibercept vial, 0.02-0.06%). Four publications reported increased rates of transient vision loss after aflibercept PFS injection versus vial-based injection. No publications reported outcomes regarding health care resource use or patient experiences.
CONCLUSIONS: The available literature supports the increased procedural efficiency of PFS versus vial-based intravitreal injection of anti-VEGFs. PFS are positively perceived by clinicians and have a safety benefit in the form of a decreased risk of endophthalmitis versus vials.
Anti-vascular endothelial growth factor (VEGF) drugs, given by injection into the eye, are commonly used to treat diseases that affect the back of the eye (the retina). Anti-VEGF drugs are provided in small containers (vials) or in syringes that are already filled with the drug (prefilled syringes). When someone is treated with an anti-VEGF drug from a vial, the drug must first be taken from the vial using a needle and syringe, and then injected. When someone is treated with an anti-VEGF drug from a prefilled syringe, the drug is injected directly from the prefilled syringe, i.e., there are fewer steps involved when a prefilled syringe is used. We searched the medical literature to see if there were differences in clinical outcomes and experiences between prefilled syringes and vials when used to inject anti-VEGF drugs. Clinicians spent about 50% less time getting ready for injections when prefilled syringes were used than when vials were used. Clinicians also preferred to use prefilled syringes than vials for injecting anti-VEGF drugs. Clinicians reported that prefilled syringes were easier to use, faster, and safer than vials. Patients who were given injections from prefilled syringes had a lower rate of infection of the inside of the eye (endophthalmitis) than patients who were given injections from vials. These results indicate that using prefilled syringes for injecting drugs into the eye can improve efficiency at ophthalmology clinics and improve safety for patients.

Intravitreal injections (IVI) of biologics targeting vascular endothelial growth factor (anti-VEGF) led to a paradigm shift in the management and prognosis of prevalent retinal conditions. Yet, IVI are typically performed with syringes that are neither developed nor approved for this purpose. Notably, syringes lubricated with silicone oil (SiO) are extensively used despite multiple reports showing that such syringes can cause deposition of SiO droplets in the vitreous body and patient discomfort. Thus, there is a need for SiO-free substitutes specifically tailored for IVI. Here, we report on the development and testing of such a syringe. This syringe has no dead volume, and its design allows for high-accuracy dosing. Also, it permits pharmaceutical compounding and storage of bevacizumab, ranibizumab, and aflibercept for up to 30 days without compromising their functional binding or transport properties. Finally, the new syringe demonstrated a favorable safety profile regarding release of SiO compared to SiO lubricated alternatives, including commercially prefilled syringes. Accordingly, the newly developed syringe is an appealing alternative for IVI.

For a plastic syringe, a stopper at the end of plunger is usually made of polydimethylsiloxane (PDMS, and co-ingredients). To reduce friction and prevent leakage between the stopper and barrel, short chain polymer of liquid PDMS is also used as lubricant. Consequently, an injection process can release solid PDMS debris from the stopper and barrel, and liquid PDMS droplets from the lubricant, both of which are confirmed herein as solid and liquid micro(nano)plastics. From molecular spectrum perspective to directly visualise those micro(nano)plastics, Raman imaging was employed to analyse hundreds-to-thousands of spectra (hyper spectrum or hyperspectral matrix) and significantly enhance signal-to-noise ratio. From morphology perspective to provide high resolution of image, scanning electron microscopy (SEM) was engaged to cross-check with Raman images and increase assignment / quantification certainty. The weak Raman imaging signal of nanoplastics was extracted using image deconvolution algorithm to remove the background noise and average the signal variation. To increase the result\'s representativeness and avoid quantification bias, multiple syringes were tested and multiple areas were randomly scanned toward statistical results. It was estimated that thousands of microplastics and millions of nanoplastics of solid/liquid PDMS might be injected when using a plastic syringe of 1 mL. Overall, Raman imaging (along with algorithm and SEM) can be helpful for further research on micro(nano)plastics, and it should be cautious to use plastic syringe due to the increasing concern on the emerging contamination of not only solid but also liquid micro(nano)plastics.

Source determination of N2O has often been performed using stable isotope incubation experiments. In situ experiments with isotopic tracers are an important next step. However, the challenge is to distribute the tracers in the field as homogeneously as possible. To examine this, a bromide solution was applied as a stand-in tracer using either a watering can, a sprayer, or syringes to a relatively dry (25% gravimetric moisture content) or wet (30%) silt loam. After 1 h, samples were taken from three soil depths (0-10 cm), and analyzed for their water content and bromide concentration. The application with syringes was unsuccessful due to blocked cannulas. Therefore, further laboratory experiments were conducted with side-port cannulas. Despite a larger calculated gravimetric soil moisture difference with watering can application, more Br- tracer was recovered in the sprayer treatment, probably due to faster transport of Br- through macropore flow in the wetter conditions caused by the watering can treatment. The losses of Br- (33% for the watering can, 28% for the sprayer treatment) are equivalent to potential losses of isotopic tracer solutions. For application of 60 at% 15NH4 +, this resulted in theoretical enrichments of 44-53 at% in the upper 2.5 cm and 7-48 at% in 5-10 cm. As there was hardly any NO3 - in the soil, extrapolations for 15NO3 - calculated enrichments were 57-59 at% in the upper 2.5 cm and 26-57 at% in 5-10 cm. Overall, no method, including the side-port cannulas, was able to achieve a homogeneous distribution of the tracer. Future search for optimal tracer application should therefore investigate methods that utilize capillary forces and avoid overhead pressure. We recommend working on rather dry soil when applying tracers, as tracer recovery was larger here. Furthermore, larger amounts of tracer lead to more uniform distributions. Further studies should also investigate the importance of plant surfaces.

OBJECTIVE: The off-label use in clinical practice of non-approved syringes for intravitreal drug administration has resulted in the detection of silicone oil drops in the vitreous of some patients. This situation derives from the lack of approved syringes for intraocular use in the Spanish market. The aim of this work is to review the use of syringes for intraocular administration, as well as to search for alternatives that meet the legal requirements for these unmet needs.
METHODS: A systematic review was performed following the PRISMA 2020 guidelines by searching PubMed with the descriptors: (silicone) AND (syringes) AND ((intraocular) OR (intravitreal)) and filtering all existing publications from January 2006 to December 2023, including all those articles dealing with silicone oil release in intravitreal injections and analysing the possible consequences.
RESULTS: Sixty-eight results were found, 23 of which were excluded because they did not deal with the subject under study, leaving a total of 45 articles for the systematic review. These were classified according to the conclusions obtained in 4 groups: the adverse reactions produced by silicone; the administration technique; the physicochemical aspects of silicone release; and the characteristics of the medical device. After reviewing the current manufacturers and technical data sheets of commercialised syringes, the existing syringes for this use have been collected, finding 2 that will probably be commercialised in Spain at the beginning of 2024: Zero Residual™ 0.2 ml SiO-free and VitreJect® Ophthalmic.
CONCLUSIONS: From the results obtained, it can be interpreted that the use of syringes and needles with silicone for intravitreal use is a concern for health professionals due to the implications and consequences that may arise in patients, the most important being adverse reactions, so it is necessary to have silicone-free syringes on the market that are specific for intraocular use. Safety and legality in the use of intraocular syringes and needles is essential to guarantee ocular integrity and patient health.

Understanding the apical pressure and irrigant flow patterns in root canals is crucial for safe and effective irrigation. Therefore, this study aimed to assess the flow characteristics of irrigants in root canal models with varying tapers during final irrigation by employing various needle designs, including a back-to-back double-side-vented needle, through computational fluid dynamics. The root canal model was configured as a closed geometrical cone with a simulated apical zone (size 30) and features tapers of 4%, 6%, and 8%. Three needle types-open-ended needle (OEN), single side-vented needle (SSVN), and double side-vented needle (DSVN)-were investigated. The results indicated that for the 4% taper models, the open-ended needle generated the maximum apical pressure, followed by the double side-vented needle and the single side-vented needle. However, in the 6% and 8% tapering root canal models, the double-side-vented needle applied the lowest maximum apical pressure. Consequently, the DSVN can pose a risk for irrigant extrusion in minimally prepared canals due to heightened apical pressure. In wider canals, the DSVN exhibited lower apical pressure. The maximum irrigant replacement was observed with OEN compared to that of the closed-ended group for both flow rates. Additionally, compared with OENs, closed-ended needles exhibited nonuniform and lower shear wall stress.

The purpose of this in vitro study was to evaluate the impact of the vertical level of the stopcock connecting the infusion line to the central venous catheter on start-up fluid delivery in microinfusions. Start-up fluid delivery was measured under standardized conditions with the syringe outlet and liquid flow sensors positioned at heart level (0 cm) and exposed to a simulated CVP of 10 mmHg at a set flow rate of 1 ml/h. Flow and intraluminal pressures were measured with the infusion line connected to the stopcock primarily placed at vertical levels of 0 cm, + 30 cm and - 30 cm or primarily placed at 0 cm and secondarily, after connecting the infusion line, displaced to + 30 cm and - 30 cm. Start-up fluid delivery 10 s after opening the stopcock placed at zero level and after opening the stopcock primarily connected at zero level and secondary displaced to vertical levels of + 30 cm and - 30 cm were similar (- 10.52 [- 13.85 to - 7.19] µL; - 8.84 [- 12.34 to - 5.33] µL and - 11.19 [- 13.71 to - 8.67] µL (p = 0.469)). Fluid delivered at 360 s related to 65% (zero level), 71% (+ 30 cm) and 67% (- 30 cm) of calculated infusion volume (p = 0.395). Start-up fluid delivery with the stopcock primarily placed at + 30 cm and - 30 cm resulted in large anterograde and retrograde fluid volumes of 34.39 [33.43 to 35.34] µL and - 24.90 [- 27.79 to - 22.01] µL at 10 s, respectively (p < 0.0001). Fluid delivered with the stopcock primarily placed at + 30 cm and - 30 cm resulted in 140% and 35% of calculated volume at 360 s, respectively (p < 0.0001). Syringe infusion pumps should ideally be connected to the stopcock positioned at heart level in order to minimize the amounts of anterograde and retrograde fluid volumes after opening of the stopcock.

OBJECTIVE: The off-label use in clinical practice of non-approved syringes for intravitreal drug administration has resulted in the detection of silicone oil drops in the vitreous of some patients. This situation derives from the lack of approved syringes for intraocular use in the Spanish market. The aim of this work is to review the use of syringes for intraocular administration, as well as to search for alternatives that meet the legal requirements for these unmet needs.
METHODS: A systematic review was performed following the PRISMA 2020 Guidelines by searching PubMed with the descriptors: \"silicone\" AND \"syringes\" AND (\"intraocular\" OR \"intravitreal\") and filtering all existing publications from January 2006 to December 2023, including all those articles dealing with silicone oil release in intravitreal injections and analysing the possible consequences.
RESULTS: Sixty-eight results were found, 23 of which were excluded because they did not deal with the subject under study, leaving a total of 45 articles for the systematic review. These were classified according to the conclusions obtained in 4 groups: the adverse reactions produced by silicone, the administration technique, the physicochemical aspects of silicone release, and the characteristics of the medical device. After reviewing the current manufacturers and technical data sheets of commercialized syringes, the existing syringes for this use have been collected, finding two that will probably be commercialized in Spain at the beginning of 2024: Zero Residual™ 0.2 ml SiO-free and VitreJect® Ophthalmic.
CONCLUSIONS: From the results obtained, it can be interpreted that the use of syringes and needles with silicone for intravitreal use is a concern for health professionals due to the implications and consequences that may arise in patients, the most important being adverse reactions, so it is necessary to have silicone-free syringes on the market that are specific for intraocular use. Safety and legality in the use of intraocular syringes and needles is essential to guarantee ocular integrity and patient health.

UNASSIGNED: Prefilled syringes (PFS) and various types of pens are available for subcutaneous injection of methotrexate (MTX) in patients with rheumatoid arthritis or moderate to severe psoriasis. A new MTX pen with modernized button-free autoinjection technology was developed as a successor to a button-activated pen (metoject®/metex® PEN). To assess the needs of users and the relevance of features of the new MTX autoinjector an international online survey was performed.
UNASSIGNED: A structured questionnaire was distributed to physicians, nurses and patients in Germany, France, and the United Kingdom. Participants received illustrations and information about features of the new MTX autoinjector.
UNASSIGNED: In total, 189 rheumatologists, 111 dermatologists, 90 nurses, and 180 patients answered the questions. Specific reasons for a preference for the use of MTX pens over PFS could predominantly be assigned to the categories \"dosing/administration\" and \"ease of use\". The first impression of the new MTX autoinjector was positive in 82% of physicians, 87% of nurses, and 76% of patients, respectively. The four most important features of the new MTX autoinjector were 2-step autoinjector mechanism (receiving a mean 14.1 to 18.1 chips of a total of 100 chips), small injection volume (9.7 to 11.7 chips), 10 different doses for dose flexibility (8.0 to 13.2 chips), and short injection time below 5 seconds (8.5 to 11.1 chips).
UNASSIGNED: Arguments for the use of MTX pens as opposed to PFS predominantly refer to dosing/administration and ease of use. The new button-free MTX autoinjector combines a number of advantageous features identified by the international survey.
Subcutaneous injection of methotrexate (MTX) is an option to treat patients with specific inflammatory diseases. A new MTX autoinjector with button-free activation of the injection and no need to build a skin fold was developed to address some of the reasons for non-adherence. The importance of specific needs of users as well as the relevance of features of the new MTX autoinjector are unknown. Therefore, a structured questionnaire was distributed to physicians, nurses and patients in Germany, France, and the United Kingdom. Illustrations and information about features of the new MTX autoinjector were distributed to the participants. The results of the study show that arguments for the use of MTX pens as opposed to prefilled syringes predominantly affect the categories dosing/administration and ease of use followed by safety/side effects. In addition, the study identified four main advantageous features of the new MTX autoinjector, ie simplicity due to the 2-step button-free autoinjector mechanism, the small injection volume, 10 different doses for dose flexibility, and the short injection time below 5 seconds.