Ellen de Kort

140 Chapter 8 pressure despite a lower cumulative propofol dose compared to the 1.0 mg/kg group. Therefore, when using propofol as premedication for endotracheal intubation, the safest strategy seems to start with a low dose of 1.0 mg/kg and titrating until effective sedation has been reached. The above-mentioned advice answers the question which propofol strategy for endotracheal intubation in preterm neonates is the safest. The question if this is safe enough and if it is justified to continue using propofol as premedication for endotracheal intubation in newborns still needs to be answered. The statement on hypotension without clinical and biochemical signs of poor perfusion being permissive, concerns the spontaneous course of blood pressure of extremely preterm infants in the first 72 hours. 17 Although most of the patients in our analysis were within their first 72 hours of life, the occurrence of hypotension was not spontaneous but induced by the administration of propofol. Although one third of patients in each of our 3 study groups did not fulfill our criteria of hypotension, MBP significantly decreased relative to baseline in almost all patients and this decrease was not restored 60 minutes after the start of propofol administration. Thewissen et al. showed that cerebral autoregulation stayed intact during episodes of hypotension caused by propofol. 27 Two other reports also could not demonstrate an important correlation between blood pressure and cerebral oxygenation in the neonatal population. 28,29 Although this finding is somewhat reassuring, the possible negative effects on short and long term outcomes of hypotension induced by the use of propofol are not known and possibly by far not as permissive as we might think. Neonatologists should ask themselves if they would expose the most vulnerable (extremely preterm) neonates to this side effect with unknown consequences on the short and on the long term. In our opinion the effect of propofol on blood pressure is a safety concern and the use of propofol should be carefully considered in every individual patient. Studies into the short term and long term effects of propofol-induced hypotension and comparison to alternative premedication strategies are warranted if propofol is continued to be used for this purpose in this population. There are some limitations to our study. At first, not all patients in our study population had indwelling arterial catheters and therefore invasively and noninvasively measured blood pressure data were combined. Secondly, data of near infrared spectroscopy monitoringwere missing on a large scale and consequentlywe have no data on cerebral oxygenation during propofol treatment.