Journal of Anesthesia

, Volume 26, Issue 4, pp 509–515 | Cite as

A comprehensive appraisal of meta-analyses focusing on nonsurgical treatments aimed at decreasing perioperative mortality or major cardiac complications

  • Massimo Zambon
  • Giuseppe Biondi-Zoccai
  • Elena Bignami
  • Laura Ruggeri
  • Alberto Zangrillo
  • Giovanni Landoni
Original Article



Millions of patients worldwide who undergo surgical procedures face significant morbidity and mortality risks. Several systematic reviews have been performed on ancillary treatments aimed at improving surgical outcomes, but their features and scholarly impact are unclear. We describe characteristics of meta-analyses on ancillary treatments aimed at improving surgical outcomes and explore factors associated with scholarly citations.


Systematic reviews published up to 2008 were searched without language restrictions in MEDLINE/PubMed. Reviews focusing on nonsurgical treatments aimed at decreasing mortality or major cardiac complications were included. Associations between content, quality, and bibliometric details and scholarly citations in several indexes were systematically appraised.


From 2,239 citations, 84 systematic reviews were identified. Patients most commonly underwent cardiovascular surgery (40.2 %), and were tested for cardiovascular drugs (25.8 %), with placebo acting as control (38.1 %). Internal validity appeared largely robust, as most (50.5 %) reviews were at low risk of bias. Normalized yearly citations for the included reviews ranged between 5.6 in Google Scholar and 4.3 in Web of Science. Multivariable analysis showed that citations were significantly and positively associated with number of authors, North American corresponding author, number of studies included, number of patients included, noncardiothoracic surgical scope, explicit funding, and lack of competing interests (all p < 0.05).


Systematic reviews currently represent a key element in defining state of the art ancillary treatments of patients undergoing surgery. However, the citation success of available meta-analyses is not significantly associated with prognostically relevant findings or quality features.


Anesthesia Meta-analysis Mortality Myocardial infarction Overview Surgery Systematic review 

Supplementary material

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Online only table 1 (DOC 152 kb)
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Online only table 2 (DOC 136 kb)
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Online only table 3 (DOC 133 kb)
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Online only table 4 (DOC 30 kb)
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Online only table 5 (DOC 35 kb)
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Online only table 6 (DOC 36 kb)
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Bland–Altman plots appraising the difference between citations in Institute for Scientific Information Web of Science and Scopus (top panel) and the difference between citations in Institute for Scientific Information Web of Science and Google Scholar (bottom panel). (TIFF 157 kb)


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Copyright information

© Japanese Society of Anesthesiologists 2012

Authors and Affiliations

  • Massimo Zambon
    • 1
  • Giuseppe Biondi-Zoccai
    • 2
  • Elena Bignami
    • 1
  • Laura Ruggeri
    • 1
  • Alberto Zangrillo
    • 1
  • Giovanni Landoni
    • 1
    • 3
  1. 1.Department of Anesthesia and Intensive CareUniversità Vita-Salute San RaffaeleMilanItaly
  2. 2.Department of Medico-Surgical Sciences and BiotechnologiesSapienza University of RomeLatinaItaly
  3. 3.Department of Cardiothoracic Anesthesia and Intensive CareIstituto Scientifico San RaffaeleMilanItaly

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