Incidence of fibroblastic sleeve in midline catheters: A pilot study in a non-intensive medical department.

BACKGROUND

Fibroblastic sleeve (FS) and catheter-related thrombosis (CRT) are both complications of venous access devices. The incidence of FS is higher than that of CRT in central venous catheters. There are no prospective studies in the literature evaluating the incidence of FS in midline catheters (MCs).

OBJECTIVE

The objective of this study was to evaluate the incidence of ultrasound-detectable FS and CRT after MCs insertion amongst patients admitted to an internal medicine ward. In addition, the correlations between the events observed and the position of the tip were analyzed.

METHODS

In this pilot prospective observational study, we recruited patients during a 12-month period (from May 2022 to April 2023). All MCs were inserted by ultrasound-guided venipuncture and ultrasound-based tip location. Patients were stratified according to tip location in two cohorts: "correct," tip in the thoracic tract of the axillary vein (optimal) or tip in the subclavian vein (acceptable), and "incorrect" with tip in the transition between the axillary/subclavian veins or in the brachial tract of the axillary vein. An ultrasound scan was performed 7-10 days after insertion. Fisher's exact test was used to assess the association between tip position and the incidence of FS or CRT.

RESULTS

In total, 41 patients were recruited. Follow-up ultrasound was available for 27 patients (65%) of the total sample, revealing 10 cases of FS (37%) and 2 cases of symptomatic CRT (7.4%). No cases of asymptomatic CRT have been found. Two patients who developed FS had the catheter tip in an incorrect position. In one of these patients, FS was associated with CRT. Both cases of symptomatic CRT were on prophylactic anticoagulants: the catheter tip was in the incorrect location, and catheter malfunction was reported. No statistically significant correlation was found between tip position and the development of complications.

CONCLUSIONS

Amongst patients with MCs, the incidence of FS is higher than CRT, and it is ultrasound-detectable 1 week after insertion. In most cases, it is asymptomatic and not associated with device malfunction. Improving FS detection is key to avoid misdiagnosis and inappropriate treatment and improved management of hospitalized patients.