Revealing Maximal Diameter of Upper Limb Superficial Vein with an Elevated Environmental Temperature

Improving healthcare professionals' ultrasound-guided peripheral vascular access ability utilizing self-assembled ultrasound phantoms: A prospective, observational quality improvement project

BACKGROUND

Ultrasound guidance can reduce the number of attempts to gain peripheral IV access while improving the success rate and satisfaction in patients with difficult IV access. Education and simulation are effective tools for improving the skills and knowledge related to ultrasound-guided peripheral IV access. Ultrasound phantom models allow for skill development without the risk of patient harm.

METHODS

Twenty-nine registered nurses and nurse practitioners were recruited for education and simulation regarding ultrasound-guided peripheral IV (USGPIV) placement. Participants completed a survey evaluating the efficacy of the phantom models in addition to pre- and post-intervention confidence, perceived competence, knowledge surveys, and a Directly Observed Procedural Skills Evaluation (DOPSE). The intervention included an educational PowerPoint and open practice session using the phantom models.

RESULTS

Statistically significant improvements were found in participants' confidence (p < 0.001; 95% CI: 5.287, 9.499; d = 1.31), perceived competence (p < 0.001; 95% CI: 1.231, 2.742; d = 1.20), knowledge (p < 0.001; 95% CI: 1.079, 2.163; d = 1.47), and skills (p < 0.001; 95% CI: 2.499; 5.501; d = 1.29). Participants improved in maintaining needle visualization (p < 0.001; 95% CI: 0.272, 0.9; d = 0.79) and decreasing their cannulation attempts (0.045; 95% CI: 0.013, 1.022; d = 0.48). Participants with no and novice experience saw statistically significant improvement across all categories (p < 0.02) compared to those with intermediate, advanced, or expert experience with ultrasound. 96.5% of participants could perform ultrasound-guided peripheral IV cannulation independently or with indirect supervision following the intervention.

CONCLUSIONS

At $36.52 per model, the self-assembled ultrasound phantom models provided a cost-effective and sustainable solution to teaching ultrasound-guided peripheral IV cannulations. Education and simulation for ultrasound-guided peripheral vascular access may benefit individuals with no or novice ultrasound experience.

Visualization of superficial vein dynamics in dorsal hand by near-infrared imaging in response to elevated local temperature

SIGNIFICANCE

Dry or moist skin-contact thermal stimulation for vein puncture (VP) and vein cannulation (VC) may not be feasible for sensitive skin. For a damaged, burned, or dark skin, near-infrared (NIR) imaging is preferred to visualize a vein. Postprocessing of NIR images is always required because the skin is a reflective material and veins need segmentation for quantitative analysis.

AIM

Our pilot study aims to observe the effect of noncontact local heating on the superficial metacarpal veins in the dorsal surface of the hand and to visualize vein dynamics using an NIR imaging system.

APPROACH

Our experiment consists of studies A and B at two ambient temperatures, 19°C and 25°C. A simple reflection-based NIR imaging system was installed to acquire sequential vein images for 5 min before and after applying 10 min of radiant thermal stimulation. To measure the vein diameter (VD), we trained a convolutional neural network (CNN) on sequential raw images to predict vein-segmentation masks as output images. Later these masked images were postprocessed for the VD measurements.

RESULTS

The average VD was significantly increased after thermal stimulation in study A. The maximum increments in VD were 39.3% and 9.19%, 1 min after thermal stimulation in studies A and B, respectively. Both the VD and skin temperature (Tskin) follow negative exponentials in time, and the VD is proportional to Tskin. A multiple linear-regression model was made to predict the final VD. A significant difference was observed in the change of the VD.

CONCLUSIONS

NIR imaging with CNN can be used for quantitative analyses of vein dynamics. This finding can be further extended to develop real-time, image-guided medical devices by integrating them with a radiant heater and to assist medical practitioners in achieving high success rates for VP or VC.

Transposed Brachial-Basilic Arteriovenous Fistula for Vascular Access in Japan

As more than 320,000 patients are currently receiving hemodialysis treatment in Japan, the creation and maintenance of hemodialysis access is a major concern. The national guidelines recommend autogenous arteriovenous hemodialysis, and the brachial-basilic arteriovenous fistula has been the focus of attention, because the need for secondary, tertiary, or even more vascular access is growing. Although favorable results have been reported in terms of patency and access-related complication, this fistula involves various unsolved or controversial issues, with limitations including complex procedures, which might contribute to the lower prevalence at this point in Japan. This review addresses those issues and discusses the role of fistula in Japan.