Comparação entre bloqueios peridural e paravertebral torácicos contínuos para analgesia pós‐operatória em pacientes submetidos a toracotomias: meta‐análise de ensaios clínicos

The article entitled ‘‘Comparison between continuous thoracic epidural and paravertebral blocks for postoperative analgesia in patients undergoing thoracotomy: systematic review’’, recently published in the Journal Revista Brasileira de Anestesiologia, brings out the authors’ concern to show the anesthetic therapy effectiveness for treating postoperative pain in chest surgery. Reading the scientific article arouses great interest in readers, however, some points need consideration: the software used for calculations, the sensitivity analysis method by successive meta-analysis, the use of mixed-effect model analysis, and the search to identify statistical heterogeneity. The software used for the search was reported in the Method and References, but the latter is incorrect, it is impossible to identify the place where it is available and to have access to the software for future searches similar to this. Successive meta-analysis was used by the authors at some point of this systematic review execution to perform the sensitivity analysis, however, the outcome of this analysis was not reported in the results or discussion, which did