Ellen de Kort

156 Chapter 9 Instead of using remifentanil as a single bolus, it could also be administered as careful continuous infusion with titration up untill sufficient effects are reached, but this strategy also needs further study. One of the reasons for single drug premedication strategies could be a reduction in preparation times. From this angle, remifentanil might be a less suitable option. Choong et al. described a preparation process including two dilution steps. 50 In our remifentanil study three dilution stepswere needed. Although preparation timeswere not measured, it was time consuming. Besides this, such a complicated preparation process with multiple dilation steps could increase the risk for preparation errors. The predictability of the final concentration in such complicated preparation could also be questioned. We performed a simulated preparation and assessed remifentanil concentrations. In 22% of the tested solutions the actual concentration was below 90% of the intended concentration and in 3% it was above 110%, confirming predictability issues with complicated preparation including several dilutional steps. This issue could be overcome by the use of pharmacy prepared prefilled syringes. The possibility and costs for using remifentanil in this way should be examined. Another potential single drug candidate is propofol. In 2007, Ghanta et al. published the first randomized controlled trial comparing propofol to the atropine-morphine- suxamethoniumcombination. Based on the time to successful intubation beingmore than twice as fast with propofol, the authors concluded that propofolwas superior in facilitating endotracheal intubation in neonates. Propofol also had the advantage of maintaining spontaneous respiration, causing less profound hypoxemia and less procedure related trauma. 38 It took more than 10 years for the second report comparing propofol with the opioid-muscle relaxant combination appeared. Durrmeyer et al. showed that there was no difference in the primary outcome of occurrence of prolonged desaturations between atropine-propofol and atropine-sufentanil-atracurium. 56 Although based on the primary outcomes of these two randomized controlled trials, propofol seemed superior or at least not inferior to the combination of an opioid with a muscle relaxant, some critical remarks should be made. Achieving sufficient sedation appeared much more difficult with propofol. In the study of Durrmeyer et al. additional doses of propofol were needed in over 50% of patients compared to the need for additional atracurium in only about 10% of patients. As a consequence, the use of propofol led to longer procedure times. Also, the quality of sedation based on the intubation conditions was poorer in the propofol group. 55 Ghanta et al. did not specifically report on the need for additional propofol or on the intubating conditions. 38 From a pharmacokinetic perspective, morphine is not a suitable candidate for use as premedication in neonatal