Background and Objectives: Thrombosis is a serious complication experienced by some hospitalized patients. While concurrent placement of two catheters (CVCs) in the same central vein offers several benefits in clinical settings, we aimed to investigate the role of this procedure in relation to the risk of thrombosis. Materials and Methods: Over a two-year retrospective analysis, we examined 114 patients with septic shock caused by a pulmonary infection, who underwent the insertion of one or more central lines into a central vein during their ICU stay. Logistic regression models were employed to assess the correlation between the Caprini risk score, the placement of two CVCs in the same vein, COVID-19 infection and the risk of venous thromboembolism (VTE). Results: In total, 53% of the patients underwent the concurrent insertion of two CVCs. The placement of two CVCs in the same vein appears to elevate the VTE risk by 2.5 times (95% CI: 1.03–6.12). Logistic regression analysis indicated that hemodialysis catheters amplify the VTE risk by nearly five times, even when accounting for a series of factors (95% CI: 1.86–12.31). Conclusions: Our study suggests that the elevated risk of VTE is likely associated with the insertion of the hemodialysis catheters rather than solely the presence of two concurrent catheters.