The prognosis of patients undergoing spinal deformity surgery is often compromised by perioperative anemia due to iron deficiency. The aim of this randomized, controlled trial was to evaluate whether postoperative ferric derisomaltose intravenous injection may improve anemia and prognosis in patients undergoing spinal deformity surgery comparing with oral iron. Participants will be randomly assigned to the treatment group (intravenous ferric derisomaltose) and the control group (oral iron). Changes in hemoglobin concentration, percentage of anemia correction, changes in iron indicators, patient quality of life, and incidence of adverse events will be analyzed to evaluate the efficacy and safety of iron isomaltoside infusion.

Iron deficiency is a common cause of perioperative anemia in patients undergoing spinal deformity surgery. Anemia may lead to increased postoperative complications and mortalities, prolonged hospital stays, deteriorated physical function, and severely affect the quality of life.

Oral iron has been widely recommended to treat perioperative anemia. However, the pro-inflammatory cytokines (such as IL-6 (Interleukin-6), TNF-a (Tumor necrosis factor-α)) produced by the inflammatory state after surgery can lead to an increase in hepcidin, which greatly affects the absorption of oral iron. Compared to oral iron, intravenous iron can circumvent the effects of decreased iron absorption in the gastrointestinal tract due to the postoperative inflammatory state and achieve faster and more effective iron supplementation. At present, intravenous iron supplements are mainly second-generation products, including iron sucrose and ferric gluconate. However, the unstable molecular structure of second-generation iron supplements may cause oxidative stress, which limits its administration in large doses.

Compared with traditional intravenous iron, the third-generation iron preparations allow more iron (1000 mg (milligram) or more, no more than 20 mg/kg (kilogram)) to be infused within a short period of time (15-60 minutes), improving patient compliance, reducing costs and complications caused by multiple infusions, and is promising to improve anemia more rapidly. Ferric derisomaltose, as the only third-generation iron currently available in China market, has showed its value in treating anemia in joint replacement surgeries. However, the effectiveness of postoperative intravenous ferric derisomaltose in spinal deformity surgery remains uncertain. Therefore, we designed this prospective randomized trial to evaluate whether intravenous ferric derisomaltose may improve anemia and prognosis in patients undergoing spinal deformity surgery compared with oral iron.

Inclusion Criteria

1. Age ≥18 years

2. Received spinal deformity surgery

3. 70 g/L ≤ Hb ≤ 110 g/L at POD1, or Hb at POD1 showed a decrease of

   ≥20 g/L compared with baseline

4. Informed consent was obtained voluntarily

Exclusion Criteria

1. Women who are pregnant, breastfeeding, or planning to become pregnant.
2. known serious hypersensitivity to other parenteral iron products
3. Non-iron deficiency anemia (e.g., hemolytic anemia)
4. Decompensated liver insufficiency
5. Coexisting active infection
6. Drug abuse, including but not limited to opioids, amphetamines, methamphetamine, ketamine, etc.
7. Other conditions that the investigator considers inappropriate for participation (e.g. deafness, Parkinson's disease, communication disorders, etc.)
8. Participation in another clinical trial within three months prior to this study.

Coded data is anticipated to be shared with potential collaborators.

Anticipated that data from the study will become available within 5 years after publication of main data.

Data would only be shared with IRB approved collaborators.