In reply: Reassessment of a meta-analysis of intraoperative cerebral-oximetry-based management studies

  • Andrés Zorrilla-VacaEmail author
  • Ryan Healy

To the Editor,

In response to the letter by Davis and Saunders,1 we carefully reviewed our article published earlier in the Journal.2First, on re-review of our original paper, we noted that we had mislabelled Figs 5 and 6 leading Davis and Saunders to mistakenly note that six articles were analyzed for postoperative delirium (POD) as shown erroneously in Fig. 6. Importantly, we did correctly state that, “Four RCTs specifically assessed for postoperative delirium. There was no significant difference…” and if Figs 5 and 6 had been correctly labelled, it would have been clear that both figures correspond to data of red blood cell transfusions (six articles) and that none of the graphs presented data related to POD. Specifically, Fig. 5 represents the overall analysis for transfusions while Fig. 6 corresponds to a subgroup analysis of transfusion outcome. In re-reviewing our original submission, we now realize that the pooled risk ratio reported in Fig. 5 is not the same as that reported...


Conflicts of interest

None declared.

Editorial responsibility

This submission was handled by Dr. Hilary P. Grocott, Editor-in-Chief, Canadian Journal of Anesthesia.

Supplementary material

12630_2019_1470_MOESM1_ESM.pdf (368 kb)
Supplementary material 1 (PDF 368 kb)


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    Davis JA, Saunders R. Reassessment of a meta-analysis of intraoperative cerebral oximetry-based management studies. Can J Anesth 2019; 66: this issue. DOI:
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Copyright information

© Canadian Anesthesiologists' Society 2019

Authors and Affiliations

  1. 1.School of MedicineUniversidad del Valle, Hospital Universitario del ValleCaliColombia
  2. 2.Graduate Medical SciencesBoston University School of MedicineBostonUSA

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