Minimising haemodynamic lability during changeover of syringes infusing norepinephrine in adult critical care patients: a multicentre randomised controlled trial.

BACKGROUND: Arterial pressure lability is common during the process of replacing syringes used for norepinephrine infusions in critically ill patients. It is unclear if there is an optimal approach to minimise arterial pressure instability during this procedures. We investigated whether 'double pumping' changeover (DPC) or automated changeover (AC) reduced blood pressure lability in critically ill adults compared with quick syringe changeover (QC). METHODS: Patients requiring a norepinephrine infusion syringe change were randomised in a non-blinded trial undertaken in six ICUs. Randomisation was minimised by norepinephrine flow rate at inclusion and centre. The primary outcome was the frequency of increased/decreased mean arterial pressure (defined by 15 mm Hg from baseline measurements) within 15 min of switching the syringe compared with QC. RESULTS: Patients (mean age: 64 (range:18-88)) yr were randomly assigned to QC (n=95), DPC (n=95), or AC (n=96). Increased MAP was the commonest consequence of syringe changeovers. MAP variability was most frequent after DPC (89/224 changeovers; 39.7%) compared with 57/223 (25.6%) changeovers after quick syringe switch and 46/181 (25.4%) in patients randomised to receive automated changeover (P=0.001). Fewer events occurred with QC compared with DPC (P=0.002). Sensitivity analysis based on mixed models showed that performing several changeovers on a single patient had no impact. Both type of changeover and norepinephrine dose before syringe changeover were independently associated with MAP variations >15 mm Hg. CONCLUSIONS: Quick changeover of norepinephrine syringes was associated with less blood pressure lability compared with DPC. The prevalence of MAP variations was the same between AC and QC. CLINICAL TRIAL REGISTRATION: NCT02304939.

Automatic versus manual changeovers of norepinephrine infusion pumps in critically ill adults: a prospective controlled study.

BACKGROUND: Norepinephrine is a key drug for treating shock but has a short half-life that requires continuous intravenous administration to maintain the constant plasma concentration needed to obtain a stable blood pressure. The small volume of the syringes used in power infusion pumps requires frequent changeovers, which can lead to norepinephrine flow interruptions responsible for hemodynamic instability. Changeovers from the nearly empty to the full syringe can be performed manually using the quick change technique (QC) or automatically using smart infusion pumps (SIP) that link two syringes. The purpose of our study was to evaluate the hypothesis that, compared to QC, SIP for norepinephrine changeovers was associated with less hemodynamic instability. METHODS: After information of the patient or next of kin, patients receiving norepinephrine for shock were allocated to QC or SIP changeovers. QC changeovers were performed by a nurse, who started a new loaded pump when the previous syringe was nearly empty. SIP changeovers were managed automatically by SIP workstations. The primary outcome was the proportion of changeovers followed by a ≥20 % drop in mean arterial pressure (MAP). RESULTS: 411 changeovers were performed, 193 in the 18 patients allocated to QC and 218 in the 32 patients allocated to SIP. Baseline patient characteristics were similar in both groups. The proportion of changeovers followed by an MAP drop ≥20 % was 12.4 % (24/193) with QC and 5.5 % (12/218) with SIP (P = 0.01). By multivariate analysis, two factors were independently associated with a significantly decreased risk of ≥20 % MAP drops during changeovers, namely, SIP (odds ratio, 0.47; 95 % confidence interval, 0.22-0.98) and norepinephrine dosage >0.5 µg/kg/min (odds ratio, 0.39; 95 % confidence interval, 0.19-0.81). CONCLUSIONS: The risk of MAP drops ≥20 % during changeovers can be significantly diminished using SIPs instead of the QC method. TRIAL REGISTRATION: Clinicaltrial.gov NCT 01127152.