Do we really need ephedrine to improve tracheal intubating conditions?

Sir, I read with interest the article about the combined effect of both priming AND ephedrine on tracheal intubating conditions 30 s after rocuronium administration (1). I have two comments. First, the authors could not find any difference, in the intubating conditions, between the control group (NPE), the ephedrine group (E) and the priming group (P). Meaning that, if we use ephedrine alone (although it increases muscle blood flow) or priming alone (although the priming dose combines with many receptors), this does not result in any better conditions than when only propofol AND rocuronium are used? If, as per the authors’ results, both do not improve intubating conditions when used alone, what was the mechanism through which the intubating conditions markedly improved after their combined use? Second, from a clinical point of view, why should we start laryngoscopy and intubation 30 s after muscle relaxant administration? Do we have enough evidence that it is better in terms of aspiration prevention than starting it after 45 s, 60 s or even after 75 s. May be if the authors waited to start laryngoscopy 60 s after rocuronium administration, they could have found acceptable conditions in all the patients without using either priming or ephedrine. Rocuronium is one of the fastest acting non-depolarizers available. Using other safe drugs during induction such as lidocaine, propofol, remifentanil or alfentanil, even with no muscle relaxant at all, has been reported to produce clinically acceptable intubation conditions (2,3). If we add rocuronium to this induction regimen even in low doses, this will result in better conditions for rapid tracheal intubation in 60 s (4). As long as we can rapidly achieve acceptable intubation conditions with this regimen, I do not think we have to use neither ephedrine nor priming or have to accept the risks that may be associated with their use such as hypertension or pulmonary aspiration (5)