Preoperative Anemia: What ITACS Can—and Cannot—Change

ITACS asks a clinically important question

Preoperative anemia is common in cardiac surgery and matters because patients begin an operation with less reserve for hemodilution and surgical blood loss. Anemia can increase the likelihood that clinicians will consider red blood cell transfusion, although hemoglobin concentration is only one part of that decision. Active bleeding, oxygen delivery, hemodynamic stability, procedural complexity, and local transfusion protocols also influence practice.

The supplied PubMed record identifies ITACS as an international randomized trial of intravenous iron for anemia before cardiac surgery. That design is appropriate for estimating whether the intervention itself changes outcomes. Randomization can balance measured and unmeasured prognostic factors more effectively than an observational comparison, reducing—but not eliminating—the risk that differences in case mix explain the findings.

The key information needed to interpret such a trial is not contained in the citation details supplied for this brief. Those details do not report the randomized population size, anemia definition, iron formulation or dose, interval between treatment and surgery, comparator, transfusion effect estimate, confidence interval, recovery outcome, adverse events, or follow-up duration. Supplying any of those figures without the article or abstract would risk fabricating evidence.

That means the defensible conclusion is narrow: ITACS is directly relevant to perioperative blood management, but the bibliographic entry alone cannot establish its implications for routine care. A statistically significant rise in hemoglobin would not necessarily prove that patients received fewer transfusions or recovered faster. Conversely, a neutral transfusion result would not establish that intravenous iron has no value in every patient or under every surgical timetable.

The result must be read beyond the headline

For transfusion outcomes, both the metric and the analysis matter. A trial may compare the proportion of patients receiving any red blood cells, the total number of units administered, transfusion rate over time or a composite outcome. Those measures answer different questions. A reduction in units concentrated among a small number of heavily transfused patients may have different bedside implications from a lower probability of any transfusion across the whole cohort.

The confidence interval is equally important. It shows the range of effects compatible with the data and helps distinguish evidence of no meaningful benefit from an inconclusive result caused by limited precision. The prespecified primary outcome should carry more weight than isolated secondary or subgroup findings, particularly when several outcomes were tested.

Recovery also needs a concrete definition. Length of stay can be influenced by discharge systems and postoperative complications. Patient-reported recovery, days alive and out of hospital, functional status, readmission and mortality capture different dimensions. Clinicians should determine when each outcome was measured and whether missing data, competing risks or deaths affected the analysis.

Timing is especially relevant for iron therapy. Cardiac operations may occur too soon after treatment for erythropoiesis to produce a large preoperative hemoglobin increase. A trial conducted mainly in scheduled procedures with a longer treatment window may not generalize to urgent surgery. Results also may differ according to whether anemia reflects absolute iron deficiency, inflammation-related iron restriction, kidney disease, ongoing blood loss, vitamin deficiency or another cause.

What current practice frameworks support

Existing patient blood management guidance supports identifying anemia before cardiac surgery, investigating its cause when time permits and incorporating treatment into a broader strategy. The 2021 multidisciplinary cardiac surgery guideline addresses anemia assessment, iron therapy, transfusion practices, blood conservation and other perioperative measures as linked components rather than interchangeable interventions.

An international surgical anemia consensus likewise emphasizes diagnosis rather than treating hemoglobin as a stand-alone disease. Iron studies and the clinical context can help distinguish iron deficiency from other causes, while the urgency of surgery determines how much evaluation and treatment are feasible. Intravenous iron may replenish iron more rapidly than oral therapy, but biological plausibility and improved laboratory values do not guarantee fewer transfusions or better clinical recovery.

Evidence from other surgical populations cannot fill the ITACS evidence gap. In the PREVENTT trial in major abdominal surgery, intravenous iron increased hemoglobin but did not reduce the primary transfusion-or-death outcome. That study demonstrates why cardiac-specific randomized evidence is necessary; it does not predict the ITACS result because operations, bleeding patterns, transfusion practices and patient characteristics differ.

For policy, ITACS should be assessed alongside existing blood-management infrastructure. Transfusion thresholds, point-of-care coagulation testing, cell salvage, antifibrinolytic use and surgical bleeding control can all affect red blood cell exposure. A trial result may therefore be influenced by the background standard of care and may not transfer unchanged to hospitals with substantially different protocols.

Decisions that remain unresolved

The full report is needed to determine whether ITACS supports routine intravenous iron for all eligible patients with anemia, selective treatment for confirmed or probable iron deficiency, or no change in practice. Absolute effects matter for this judgment. Even a favorable relative estimate can have limited operational value when the absolute reduction is small, treatment must occur weeks in advance or many patients must be treated to avoid one transfusion.

Safety requires the same scrutiny. Relevant questions include infusion reactions, infection, cardiovascular events, surgery delays and withdrawals after randomization. Rare harms may not be excluded even by a moderately large trial, and safety findings must be interpreted with the confidence intervals and completeness of follow-up.

Important limitations to examine include masking, adherence, crossover, variation among countries and centers, the proportion of screened patients enrolled, and whether transfusion decisions followed standardized criteria. Funding and investigator conflicts should also be reviewed in the published report. Without those details, neither a favorable nor a neutral headline can establish how broadly the findings apply.

The immediate practical message is therefore not to ignore preoperative anemia. It is to separate two questions: whether anemia should be detected and evaluated, which established blood-management frameworks support, and whether routine intravenous iron improves patient-centered outcomes in the specific population studied by ITACS. The second question requires the complete randomized data.

Questions clinicians ask

Should every patient with anemia receive intravenous iron before cardiac surgery?

Not on the basis of the supplied citation alone. The decision depends on the trial’s eligibility criteria, anemia and iron-deficiency definitions, treatment window, absolute effect and safety findings, none of which can be quantified from the information provided here. Current frameworks favor evaluating the anemia’s cause rather than treating automatically based only on hemoglobin.

Is a higher preoperative hemoglobin enough to establish benefit?

No. Hemoglobin response is a biologic or surrogate outcome; the clinically relevant questions are whether treatment reduces red blood cell exposure, complications or impaired recovery. PREVENTT illustrates that intravenous iron can improve hemoglobin without necessarily changing a primary transfusion-related clinical outcome in another surgical setting.

Would a neutral ITACS result mean intravenous iron never helps?

No. A neutral overall estimate could reflect adequate usual care, treatment too close to surgery, inclusion of anemia not driven by iron deficiency, limited precision or a genuinely small effect. Prespecified subgroup evidence may be informative, but interpret it cautiously and do not override the primary analysis without strong statistical support.

What should hospitals examine before changing a pathway?

Hospitals should review ITACS’s absolute and relative effects, confidence intervals, adverse events, follow-up, treatment timing and applicability to their case mix. They should also compare the trial’s transfusion protocol and background blood-conservation practices with local care, because those factors can materially affect both transfusion rates and the expected value of adding intravenous iron.

References

1. Intravenous iron to treat anaemia before cardiac surgery (ITACS): international randomized trial — PubMed, 2026 2. STS/SCA/AmSECT/SABM Update to the Clinical Practice Guidelines on Patient Blood Management — Journal of ExtraCorporeal Technology, 2021 3. Recommendations From the International Consensus Conference on Anemia Management in Surgical Patients (ICCAMS) — Annals of Surgery, 2023 4. Preoperative intravenous iron to treat anaemia before major abdominal surgery (PREVENTT): a randomised, double-blind, controlled trial — The Lancet, 2020