Predictors of haemodynamic instability during the changeover of norepinephrine infusion pumps

BACKGROUND Changeovers of norepinephrine infusion pumps (CNIPs) frequently lead to haemodynamic instability. The aim of this study was to identify risk factors for haemodynamic instability associated with CNIP, independent of the method used to perform the relay. METHODS We performed a prospective study, in a university-affiliated intensive care unit. Over a 1-year period, all adult patients who had at least one CNIP were included. CNIPs were automatically performed using smart pumps, in accordance with a standardised protocol. CNIP-induced haemodynamic instability was defined as a variation in mean arterial pressure (MAP) >25 %. A multivariate mixed effects logistic regression was fitted to assess the factors associated with CNIP-induced haemodynamic instability. RESULTS From the 118 patients included in the study, 764 CNIPs were analysed. Most of the patients were treated with norepinephrine for septic shock of medical origin (n = 83, 70 %). Haemodynamic instability occurred 114 times (15 %) in 63 patients (53 %). Among the risk factors identified by the univariate analysis (age, heart rate, dose of norepinephrine infused, and change in the concentration of the vasoactive drug; p < 0.05), change in the norepinephrine concentration was the only independent risk factor for CNIP-induced haemodynamic instability identified in the multivariate analysis (adjusted OR 11.8, 95 % CI 7.2-19.5, p < 0.001). CONCLUSIONS Changes in the norepinephrine concentration during CNIPs lead to a high risk of haemodynamic instability, while the clinical severity of patients, as well as the doses of norepinephrine, was not.