Predicting PICC-related deep vein thrombosis
Abstract:
Background: The Michigan Risk Score (MRS) was developed to predict peripherally inserted central catheter (PICC)-related thrombosis. This study aimed to externally validate the MRS in a Brazilian cohort.
Methods: Adults hospitalized in 16 Brazilian hospitals who received a PICC were followed until catheter removal, death, or 30 days. The MRS assigned risk points based on 5 clinical variables: presence of another central line, white blood cell count >12 000, multi-lumen PICC, history of deep vein thrombosis (DVT), and active cancer. Mixed-effects logistic regression assessed MRS performance, including calibration and discrimination.
Results: A total of 12 725 PICCs in 11 135 patients (mean age 66.4 ± 19 years; 51% female) were included. Deep vein thrombosis occurred in 129 cases (1.0%). Only the number of PICC lumens and history of venous thromboembolism (VTE) were significantly associated with DVT risk. Compared to risk class I, the odds ratios for risk classes III and IV were 2.83 (95% CI, 1.51-5.3) and 3.01 (95% CI, 1.41-6.41), respectively. The area under the curve was 0.70 for the multivariable model and 0.67 for the MRS classification.
Conclusions: Peripherally inserted central catheter lumens and VTE history were independently associated with DVT risk. Classes III and IV of the MRS had higher event rates than class I.
Reference:
Rabelo-Silva ER, Saffi MAL, Hirakata VN, Ferro EB, Lourenço SA, da Silva AIM, da Luz CC, Pupin VC, Cechinel RB, de Andrade LM, Silva TCDC, de Araújo MM, Do Espírito Santo FRF, da Gama LA, Soares VS, Montenegro WS, de Jesus TS, de Freitas GRC, Pedraza LL, Veçossi DDSG, Gimenez FJ, Barbosa R, Chopra V; PICC-BRAZIL RESEARCH GROUP. External Validation of the Michigan Risk Score for Predicting Peripherally Inserted Central Catheter-Related Deep Vein Thrombosis: A Multicenter Study in Brazil. J Infus Nurs. 2026 Jan-Feb 01;49(1):43-51. doi: 10.1097/NAN.0000000000000623. Epub 2025 Dec 23. PMID: 41494176.