Point-of-Care Ultrasound-Guided Protocol to Confirm Central Venous Catheter Placement in Pediatric Patients Undergoing Cardiothoracic Surgery: A Prospective Feasibility Study

Central venous catheter tip positioning using ultrasound in pediatric patients-A prospective observational study

BACKGROUND

In children, central venous catheter (CVC) placement is usually performed under ultrasound guidance for optimal visualization of vessels and reduction of puncture-related complications. Nevertheless, in many cases, additional radiographic examinations are performed to check the position of the catheter tip.

AIM

The primary objective of this observational feasibility study was to determine the number of ultrasound-guided central venous catheter tips that can be identified in a subsequent position check using ultrasonography. Furthermore, we investigated the optimal ultrasound window, time expenditure, and success rate concerning puncture attempts and side effects. In addition, we compared the calculated and real insertion depths and analyzed the position of the catheter tip on postoperative radiographs with the tracheal bifurcation as a traditional landmark.

METHODS

Ninety children with congenital heart defects who required a central venous line for cardiac surgery were included in this single-center study. After the insertion of the catheter, the optimal position of its tip was controlled using one of four predefined ultrasound windows. A chest radiograph was obtained postoperatively in accordance with hospital standards to check the catheter tip position determined by ultrasonography.

RESULTS

The children had a median (IQR) age of 11.5 (4.0, 58.8) months and a mean (SD) BMI of 15.3 (2.91) kg/m2 Ultrasound visualization of the catheter tip was successful in 86/90 (95.6%) children (95% confidence interval [CI]: 91.3%, 99.8%). Postoperative radiographic examination showed that the catheter tip was in the desired position in 94.4% (95% CI: 89.7%, 99.2%) of the cases. None of the children needed the catheter tip position being corrected based on chest radiography.

CONCLUSION

Additional radiation exposure after the placement of central venous catheters can be avoided with the correct interpretation of standardized ultrasound windows, especially in vulnerable children with cardiac disease.

Nanozymes towards Personalized Diagnostics: A Recent Progress in Biosensing

This review highlights the recent advancements in the field of nanozymes and their applications in the development of point-of-care biosensors. The use of nanozymes as enzyme-mimicking components in biosensing systems has led to improved performance and miniaturization of these sensors. The unique properties of nanozymes, such as high stability, robustness, and surface tunability, make them an attractive alternative to traditional enzymes in biosensing applications. Researchers have explored a wide range of nanomaterials, including metals, metal oxides, and metal-organic frameworks, for the development of nanozyme-based biosensors. Different sensing strategies, such as colorimetric, fluorescent, electrochemical and SERS, have been implemented using nanozymes as signal-producing components. Despite the numerous advantages, there are also challenges associated with nanozyme-based biosensors, including stability and specificity, which need to be addressed for their wider applications. The future of nanozyme-based biosensors looks promising, with the potential to bring a paradigm shift in biomolecular sensing. The development of highly specific, multi-enzyme mimicking nanozymes could lead to the creation of highly sensitive and low-biofouling biosensors. Integration of nanozymes into point-of-care diagnostics promises to revolutionize healthcare by improving patient outcomes and reducing costs while enhancing the accuracy and sensitivity of diagnostic tools.

Lower Patient Height and Weight Are Predisposing Factors for Complex Radial Arterial Catheterization

Background: Radial artery (RA) catheterization for invasive blood pressure monitoring is often performed via palpation, and an ultrasound is used secondarily only in case of multiple unsuccessful attempts. Although more elaborate, it has been shown that primary ultrasound-guided catheterization may be advantageous compared with palpation. The aim of this study was to identify factors associated with difficult RA catheterization. Methods: Left RA ultrasound assessments were performed in patients with indicated invasive blood pressure monitoring the day before surgery. RA catheterization was performed by personnel blinded to the ultrasound results. Based on the number of attempts needed for successful catheter placement, the cohort was divided into uncomplicated (group 1) and difficult (more than one attempt, group 2) catheterization cases. Cases subjected to primary ultrasound were excluded from the analysis. Results: Body weight, height and surface area (BSA) of patients in group 2 (n = 16) were significantly lower than those of patients in group 1 (n = 25), and internal RA diameters were significantly smaller in group 2 patients. In the whole cohort, BSA was significantly associated with distal and proximal internal RA diameters. In contrast, no differences were observed in the skin-to-artery distance, the longitudinal axis deviation (kinking) or blood flow velocity. Median time to successful catheterization was 77 (47–179) s. Prolonged time needed for cannulation was significantly associated with lower body weight, BMI and BSA, and with reduced distal and proximal internal RA diameter. Conclusions: RA catheterization performed through pulse palpation may be difficult, especially in adult patients with lower body weight and height, due to reduced arterial diameters. Initial use of ultrasound in these patients may reduce first-attempt failure, preventing procedural delays and patient discomfort.