Introduction: Midline catheters are widely used in clinical practice. Proper placement of midline catheter tip is usually assessed only by aspirating blood and flushing with normal saline without resistance. Purpose: To describe the ultrasound-guided tip location for midline catheters and its feasibility and to compare incidence of catheter-related venous thrombosis associated with or without ultrasound tip localization. Methods: The ultrasound-guided tip location is described step by step. Feasibility of the technique and incidence of catheter-related venous thrombosis were measured (study group) and compared with two historical groups: study group, 20-cm midline catheters inserted with ultrasound-guided tip location; group 1, 25-cm midline catheters inserted without ultrasound-guided tip location and group 2, 20-cm midline catheters inserted without ultrasound-guided tip location. Results: In the study group, ultrasound-guided tip location was easily feasible in 98.9% of patients. Incidence of catheter-related venous thrombosis was 2.42% in control group 1, 9% in control group 2 and 2.62% in the study group. Discussion: In the study group and control group 1, the tip was placed in the axillary vein, about 3 cm distal to the clavicle and in the subclavian vein. In control group 2, the tip was probably located at the transition between the axillary and the subclavian vein. It is possible that such position may have been associated with an increased incidence of catheter-related venous thrombosis. Conclusion: The ideal position of the tip of a midline catheter might be inside the axillary vein, about 3 cm distal to the axillary-subclavian transition or inside the subclavian vein. Ultrasound-guided tip location is safe, inexpensive, easy and potentially useful during midline catheters insertion.

Introduction: Peripherally inserted central catheters are very common devices for short, medium and long-term therapies. Their performance is strictly dependent on the correct tip location, at the junction between the upper caval vein and the right atrium. It is very important to obtain an estimated measure of the catheter, in order to reach the cavo-atrial junction and optimize the catheter length. Estimated measures are often obtained using cutaneous landmarks. Objective: Evaluate the reliability of cutaneous landmark-based length estimation during catheter insertion. Identify any patient’s related factors that may affect cutaneous landmarks reliability. Methods: We used two distinct techniques and collected data about cutaneous landmark-based length estimation, electrocardiographic guided intravascular length, age, weight and height. We studied the reliability of possible correcting factors, balancing the error average by regression models, and we found and tested two different models of prediction. Results: A total number of 519 patients were studied. The average bias, between the two studied length assessment by cutaneous landmarks and electrocardiographic guided catheter length, were 3.77 ± 2.44 cm and 3.28 ± 2.57 cm, respectively. The analysed prediction models (deviance explained 43.5%, Akaike information criterion = 1313.67% and 43.4%, Akaike information criterion = 1313.92), fitted on the validation set, showed a root mean square error of 3.07 and 3.06. Conclusion: Landmark-based length estimation for preventive catheter length assessment seems to be unreliable, when associated with post-procedural tip location. They are useful for distal trimming catheters to optimize the ‘out of skin’ portion when associated with electrocardiographic tip location. Models identified for balancing bias are probably not useful.

Background: Arterial lines and central venous catheter (CVC) allow to monitor patients’ acid-base status and gas exchange. Their placement and maintenance may however be burdened by severe complications. Midline Catheters (MC) are peripheral venous accesses that are less invasive and easier to insert compared to CVC and arterial lines. Methods: A prospective observational study was performed including stabilized critical patients with clinical indication to midline positioning before intensive care unit (ICU) discharge. The primary aim was to assess if venous sampling from MCs can be a reliable alternative to CVC for pH and CO2 monitoring. The secondary aim was to evaluate the correlation between samplings from MC, CVC and arterial line with regards to pH, carbon dioxide tension (pCO2), lactates and electrolytes. Three samples from CVC, arterial line and MC were collected simultaneously. Agreement and correlation of the studied parameters between different sampling sites were explored. Results: 40 patients were included in the analysis. A good agreement for pH and pCO2 was recorded between MC and CVC: mean differences were 0.001 (95% CI −0.006 to 0.007) and 0.7 (−0.1 to 1.5), percentage error 0.4% and 11.2%, respectively. Correlation between MC and both central venous and arterial samples for pH, pCO2, lactates and electrolytes was found to be moderate-to-strong (Pearson’s R coefficient range 0.59–0.99, p < 0.001 for all these parameters). Conclusions: In stabilized critical patients, midline catheters represent a reliable alternative to CVC and arterial lines to monitor acid-base disturbances, CO2 levels and electrolytes. The present findings add to the known advantages of MC, which might be considered a first-line vascular access for non-critical or stabilized patients who do not require infusion of vesicant or irritant drugs.

Background: Femorally inserted central catheters are increasingly used, especially after the COVID-19 pandemic, also thanks to widespread of tunneling techniques that allow the exit site to be moved away from the groin. Methods: In this retrospective observational study, femorally inserted catheters, with exit site at mid-thigh and the tip in Inferior vena cava or in Inferior vena cava at the junction with right atrium, have been observed and complications have been analyzed. All catheters were inserted by trained Nurses of a tertiary hospital Vascular Access Team. Results: In 142 catheters (126 inserted via common femoral vein and 16 inserted via superficial femoral vein) and 3060 catheter days, we observed an infection rate of 1.3 events/1000 catheter days (all of them in oncologic patients and up to 30 days of catheterization), 2 cases of thrombotic events (1.41%) and 17 cases of accidental removal (11.97%). Other rare complications, as primary malposition, tip migration, arterial pseudoaneurysm, have been recorded. The average length of catheters inserted, from the exit site to the tip, was 47.6 ± 2.4 cm. Conclusion: The attention to the correct position of the tip, the exit site at mid-thigh and the new techniques during insertion make these femoral catheters as safe as other central vascular access devices. For this kind of central access device, a catheter at least 50 cm long is needed.