A new inexpensive ultrasound-guided central venous catheterization simulation model.

BACKGROUND: Central venous catheters (CVCs) are life-saving tools for fluid therapy during surgery. Ultrasound-guided CVC placement has been shown to be safe and highly efficient. However, it is difficult for medical workers with less experience in ultrasonography to acquire the necessary skill in a short time. Simulation-based training is a good way to enhance the skill of a beginner. Therefore, in this study, we introduced a new, inexpensive and easily implemented model for ultrasound-guided CVC placement training and assessed the feasibility of this model. METHODS: This was a quasi-experimental study. Thirty-three anaesthesiology postgraduate year 2 and 3 residents with strong CVC interest were included in a simulator-based training workshop in a department of anaesthesiology. The simulation model consisted of a piece of pork and two latex catheters filled with red and blue ink. The workshop comprised 3 parts: a 10-min introductory lecture, a 15-min orientation on performing ultrasound-guided CVC insertion based on the model, and a 30-min practice session. Participants completed relevant questionnaires before and after the training. Moreover, an examination was held to evaluate their skill with the novel model. RESULTS: All participants indicated that the novel model increased their self-perceived confidence in ultrasound-guided catheterization. They also all reported that the model was adequate for training anaesthesiology residents in ultrasound-guided catheterization. A few individuals thought the model did not mimic the progress of CVC insertion (3 of 33). After training, participants did not show a significant difference in the acquisition of central venous catheterization theory. However, their competency with ultrasound-guided CVC placement was enhanced. This was demonstrated not only based on subjective answers to the following questions, namely, "how do you perform central venous catheterization with ultrasound guidance?" (p < 0.001), "can you perform ultrasound-guided central venous catheterization?" (p < 0.001), and "how much self-confidence do you have in performing ultrasound-guided central venous catheterization?" (p < 0.001), but also in objective performance (evaluation of the core step in ultrasound-guided placement (p < 0.001)). CONCLUSION: The new simulator is a feasible, inexpensive and easily reproducible tool for training anaesthesiologists in ultrasound-guided central venous catheterization. After the simulation-based training workshop, the competency of residents in performing central venous catheterization with ultrasound guidance improved.

Gold/alpha-lactalbumin nanoprobes for the imaging and treatment of breast cancer.

Theranostic agents should ideally be renally cleared and biodegradable. Here, we report the synthesis, characterization and theranostic applications of fluorescent ultrasmall gold quantum clusters that are stabilized by the milk metalloprotein alpha-lactalbumin. We synthesized three types of these nanoprobes that together display fluorescence across the visible and near-infrared spectra when excited at a single wavelength through optical colour coding. In live tumour-bearing mice, the near-infrared nanoprobe generates contrast for fluorescence, X-ray computed tomography and magnetic resonance imaging, and exhibits long circulation times, low accumulation in the reticuloendothelial system, sustained tumour retention, insignificant toxicity and renal clearance. An intravenously administrated near-infrared nanoprobe with a large Stokes shift facilitated the detection and image-guided resection of breast tumours in vivo using a smartphone with modified optics. Moreover, the partially unfolded structure of alpha-lactalbumin in the nanoprobe helps with the formation of an anti-cancer lipoprotein complex with oleic acid that triggers the inhibition of the MAPK and PI3K-AKT pathways, immunogenic cell death and the recruitment of infiltrating macrophages. The biodegradability and safety profile of the nanoprobes make them suitable for the systemic detection and localized treatment of cancer.