To the Editor We read with interest the article published by Chaaban and colleagues.1 While the authors are to be commended for their study, there are a few points that we think should be addressed.
First, anesthetic technique: While both groups received fentanyl at induction, it is not clear which opioid or analgesic patients received during maintenance. Did patients receive an opioid during maintenance of anesthesia? If yes, how much? This question arises because of the surprisingly high concentrations of propofol required during anesthesia. In fact, it is easy to demonstrate by means of a simple computer simulation that 200 µg/kg/min (or 12 mg/kg/h) corresponds to a propofol concentration of almost 5 µg/mL after less than 1 hour of infusion The possible difference in opioid amounts could have had an impact on the amount of propofol or sevoflurane needed to reach the same level of hypotension.
La Colla L, Albertin A. No Difference in Blood Loss During Endoscopic Sinus Surgery With Total Intravenous Anesthesia?. JAMA Otolaryngol Head Neck Surg. 2013;139(10):1077. doi:10.1001/jamaoto.2013.5044