Letters to Editor
Caffeine for the prevention of postoperative nausea and vomiting — Reply Sir, I read with pleasure the letter to the editor regarding our paper entitled “Caffeine for the prevention of postoperative nausea and vomiting (PONV),” which was published in your journal. While our paper represents a first ever prospective, randomized, double-blind, placebo-controlled study examining the effects of intravenous caffeine on PONV rates and other side-effects of general anesthesia, more studies are needed to potentially uncover any positive effects of caffeine on postoperative recovery. In our study, we attempted to account for as many PONV risk factors as possible, and control for them appropriately. For example, we controlled for four major risk factors such as female gender, smoking status, prior history of PONV, and perioperative opioid use. In addition, we controlled for baseline caffeine consumption, duration of anesthesia, and type of surgery all known to potentially influence study results. In addition, we made every attempt to standardize induction and maintenance of anesthesia among different practitioners. All patients received intravenous induction with propofol, and anesthesia was maintained with an inhalational agent. Overall, this was a well-controlled study. In fact, the most recent PONV guidelines from the Society for Ambulatory Anesthesia published a list of overall positive risk factors, which were all acknowledged and controlled for in our study. As far as intravenous fluid administration is concerned, we agree that there is some evidence that high amount of intravenous fluid administration can reduce postoperative emesis.[5,6] Our ambulatory anesthesia practitioners follow internally developed ambulatory anesthetic protocols that allow little room for variation. In our study, most patients would have received similar amounts of fluid as these cases were generally short and similar in duration; similarly, although we did not report the intraoperative dose of the inhalational agent(s), we believe it would have had a minor effect on the reported outcomes. In summary, our pilot study explores the possibility of using a different drug modality (intravenous caffeine) for the prevention of PONV and other anesthetic side-effects. Larger prospective studies are warranted to further explore this drug’s potential.
Acknowledgments The authors thank Daniel W. Steinbrook, Anna T. R. Legedza, ScD, and Valerie Banner-Goodspeed for assistance with data analysis. ClinicalTrials.gov ID NCT00130026. 578
Richard D Urman, Frances Garfield1, Stacey H Batista1, Richard A Steinbrook1 Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, 1Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA Address for correspondence: Dr. Richard D Urman, Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA. E-mail: [email protected]
Steinbrook RA, Garfield F, Batista SH, Urman RD. Caffeine for the prevention of postoperative nausea and vomiting. J Anaesthesiol Clin Pharmacol 2013;29:526-9. Apfel CC, Läärä E, Koivuranta M, Greim CA, Roewer N. A simplified risk score for predicting postoperative nausea and vomiting: Conclusions from cross-validations between two centers. Anesthesiology 1999;91:693-700. Gan TJ. Risk factors for postoperative nausea and vomiting. Anesth Analg 2006;102:1884-98. Gan TJ, Diemunsch P, Habib AS, Kovac A, Kranke P, Meyer TA, et al. Consensus guidelines for the management of postoperative nausea and vomiting. Anesth Analg 2014;118:85-113. Goodarzi M, Matar MM, Shafa M, Townsend JE, Gonzalez I. A prospective randomized blinded study of the effect of intravenous fluid therapy on postoperative nausea and vomiting in children undergoing strabismus surgery. Paediatr Anaesth 2006;16:49-53. Maharaj CH, Kallam SR, Malik A, Hassett P, Grady D, Laffey JG. Preoperative intravenous fluid therapy decreases postoperative nausea and pain in high risk patients. Anesth Analg 2005;100:675-82. Access this article online Quick Response Code:
Cesarean section under local anesthesia: A step forward or backward? Sir, Cesarean sections are most commonly performed under spinal anesthesia. However, there are many cases where local anesthesia has been highly useful and even life saving such as
Journal of Anaesthesiology Clinical Pharmacology | October-December 2014 | Vol 30 | Issue 4
Copyright of Journal of Anaesthesiology Clinical Pharmacology is the property of Medknow Publications & Media Pvt. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.