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Iron supplementation for patients undergoing cardiac surgery: a systematic review and meta-analysis of randomized controlled trials

Supplémentation en fer pour les patients bénéficiant d’une chirurgie cardiaque : une revue systématique et une méta-analyse d’études randomisées contrôlées



Iron supplementation has been evaluated in several randomized controlled trials (RCTs) for its potential to increase baseline hemoglobin and decrease red blood cell transfusion during cardiac surgery. This study’s main objective was to evaluate the current evidence for iron administration in cardiac surgery patients.


We searched MEDLINE, EMBASE, CENTRAL, Web of Science databases, and Google Scholar from inception to 19 November 2020 for RCTs evaluating perioperative iron administration in adult patients undergoing cardiac surgery. The RCTs were assessed using a risk of bias assessment and the quality of evidence was assessed using the grading of recommendations, assessments, development, and evaluations.


We reviewed 1,767 citations, and five studies (n = 554) met the inclusion criteria. The use of iron showed no statistical difference in incidence of transfusion (risk ratio, 0.86; 95% confidence interval, 0.65 to 1.13). Trial sequential analysis suggested an optimal information size of 1,132 participants, which the accrued information size did not reach.


The current literature does not support or refute the routine use of iron therapy in cardiac surgery patients.

Trial registration

PROSPERO (CRD42020161927); registered 19 December 2019.



La supplémentation en fer a été évaluée dans plusieurs études randomisées contrôlées (ERC) pour son potentiel à augmenter l’hémoglobine de base et à diminuer la transfusion d’érythrocytes pendant la chirurgie cardiaque. L’objectif principal de cette étude était d’évaluer les données probantes actuelles soutenant l’administration de fer chez les patients de chirurgie cardiaque.


Nous avons effectué des recherches dans les bases de données MEDLINE, EMBASE, CENTRAL, Web of Science et Google Scholar de leur création jusqu’au 19 novembre 2020 pour en extraire les ERC évaluant l’administration périopératoire de fer chez les patients adultes bénéficiant d’une chirurgie cardiaque. Les ERC ont été évaluées à l’aide d’une évaluation du risque de biais et la qualité des données probantes a été évaluée à l’aide du système de notation GRADE.


Nous avons examiné 1767 citations et cinq études (n = 554) répondaient aux critères d’inclusion. L’administration de fer n’a montré aucune différence statistique dans l’incidence des transfusions (risque relatif, 0,86; intervalle de confiance à 95 %, 0,65 à 1,13). Selon l’analyse séquentielle des études, la taille d’information optimale serait de 1132 participants, une taille que l’information accumulée n’a pas atteint.


La littérature actuelle ne soutient ni ne réfute l’utilisation systématique d’une thérapie à base de fer chez les patients de chirurgie cardiaque.

Enregistrement de l’étude

PROSPERO (CRD42020161927); enregistrée le 19 décembre 2019.

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Author contributions

Stephen Su Yang, Matthew J. Cameron, Latifa Al Kharusi, Pouya Gholipour Baradari, Adam Gosselin, and Anissa Chirico contributed to study conception and design and drafting the manuscript. Stephen Su Yang, Matthew J. Cameron, Latifa Al Kharusi, Pouya Gholipour Baradari, and Anissa Chirico contributed to acquisition and analysis of data. Stephen Su Yang and Matthew J. Cameron contributed to interpretation of data.



Funding statement

Matthew J. Cameron holds a foundation grant from la Fondation d'anesthésiologie and réanimation du Québec.

Editorial responsibility

This submission was handled by Dr. Philip M. Jones, Deputy Editor-in-Chief, Canadian Journal of Anesthesia/Journal canadien d’anesthésie

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Correspondence to Stephen Su Yang MDCM, MSc.

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Yang, S.S., Al Kharusi, L., Gosselin, A. et al. Iron supplementation for patients undergoing cardiac surgery: a systematic review and meta-analysis of randomized controlled trials. Can J Anesth/J Can Anesth (2021).

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  • Cardiac surgery
  • Iron
  • Anemia
  • Blood transfusion