Remifentanil versus sufentanil continuous infusion for sedation in mechanically ventilated patients

Introduction

The first objective of this study was to compare the effectiveness of remifentanil and sufentanil as sedative agents in mechanically ventilated patients to achieve a Ramsay sedation score (RSS) of 2–3.

Methods

Twenty (12 males, eight females) mechanically ventilated (pressure support) patients requiring analgesia and sedation were included in the study. Patients were assigned randomly to group R (eight patients, remifentanil) or to group S (12 patients, sufentanil). In group S at ICU admission sufentanil infusion was started at 0.003 μg/kg/min. In group R at ICU admission remifentanil infusion was started at 0.05 μg/kg/min. As rescue dose a bolus of 1–2 mg midazolam was administered to reach the predefined RSS or to facilitate nursing procedures. If adequate sedation was not reached after 6 hours or before, in the case of more than three consecutive midazolam rescue dose administrations without reaching the target RSS, the continuous infusion rate was increased up to 0.01 μg/kg/min in group S and up to 0.1 μg/kg/min in group R, respectively. Neurological (RSS, GCS, VAS), hemodynamic (HR, mAP) and respiratory (TV, PEEP/Paw, RR, PaO₂/FiO₂, PaCO₂, HCO₃^-) data were evaluated at a predefined step from the HCO₃ induction of sedation (T0) and every 30 min (T30, T60, T90, T120) and then during sedation maintenance every 6 hours (T6, T12, T18, T24, T30, T36, T42, T48). After 48 hours the observation ended. Statistical analysis was performed with the Kruskal–Wallis test and comparisons with baseline values with the Dunn test. P < 0.05 were considered statistically significant.

Results

RSS during the study period are reported in Figs 1 and 2. Sufentanil and remifentanil mean dosages administered were, respectively, 0.003 ± 0.001 μg/kg/min (range from 0.0009 to 0.01) and 0.07 ± 0.03 μg/kg/min (range from 0.01 to 0.18). No respiratory depression (RR < 8) was observed.

Figure 1

(abstract P136)

Figure 2

(abstract P136)

Conclusions

These preliminary results show that either sufentanil or remifentanil are effective and safe as analgosedative agents in mechanically ventilated critically ill patients.