Risk factors associated with umbilical vascular catheter-associated thrombosis in newborn infants

Objective: To determine the risk factors associated with umbilical vascular catheter-associated thrombosis. Methods: All consecutive inborn infants with umbilical arterial (UAC) and/o r umbilical venous catheters (UVC) inserted for more than 6 h duration were included in the study. Each infant was screened for thrombosis in the abdo minal aorta and inferior vena cava by 2-D abdominal ultrasonography within 48-72 h of insertion of umbilical vascular catheters. Subsequent serial sca nning was performed at intervals of every 5-7 days, and within 48 h after r emoval of catheters. Results: Upon removal of umbilical catheters, abdominal aortic thrombi were detected in 32/99 (32.3%) infants with UAC. Small thrombi were detected in the inferior vena cava of 2/49 (4.1%) infants with UVC (one of whom had bo th UAC and UVC). When compared with those who received only UVC (n = 18), i nfants who received either UAC atone (n = 68) or both UAC and UVC (n = 31) had significantly higher risk of developing thrombosis (odds ratio (OR): 7. 6, 95% confidence interval (CI): 1.1, 325.5)). Logistic regression analysis of various potential risk factors showed that the only significant risk fa ctor associated with the development of abdominal aortic thrombosis followi ng insertion of UAC was longer duration of UAC in situ (for every additiona l day of UAC in situ, adjusted OR of developing thrombosis was: 1.2, 95% CI : 1.1, 1.3; P = 0.002). Conclusion: Umbilical arterial catheter-associated thrombosis was common. U mbilical arterial catheter should be removed as soon as possible when not n eeded. Upon removal of UAC, all infants should be screened for abdominal ao rtic thrombus by 2-D ultrasonography.