A clinical rule for the difficulty prediction on scalp intravenous access in infants (SIAI) from emergency room

Infant intravenous access poses a significant challenge to the operator. Scalp vein is the ideal location for emergency medical staff to perform intravenous access for administration of fluids or medications. To tackle this challenge, we developed a clinical rule for the difficulty prediction on scalp intravenous access in infants (SIAI) conducting a prospective cohort study in a pediatric emergency room. A total of 658 infant patients who underwent SVI from January 2017 to September 2018 were recruited in this study. The failure rate of SIAI on the first attempt was 20.2%. Five variables, including dehydration condition, obesity, vein invisibility, vein impalpability and hyperactive status of infant, were independently and statistically associated with failure rate of SIAI. Furthermore, we indicated that any one alone of the above five variables did not significantly lead to greater than 50% failure rate of indwelling needle SIAI (p > 0.05). However, summary effects of more than one of these five variables were statistically significant associated with greater than 50% failure rate of SIAI (p < 0.05). When employing the five-variable model, validation cohort subjects displayed dehydration, obesity, vein invisibility, vein impalpability and hyperactive status had a 67.5% likelihood of failed first attempt on SIAI (C = 0.675; 95% CI: 0.622–0.727; p < 0.001). For the first time, we developed the difficult model for SIAI. We found that dehydration, obesity, vein invisibility, vein impalpability and hyperactive status of the infant patients are the independent and significant predictors associated with SIAI failure. Our predicted model indicates that infant patients with combination of more than one of the five variables contribute to greater than 50% failure rate of indwelling needle in SIAI.