Abstract
Iron supplementation provides iron storage and facilitates effective production of
hemoglobin. The purpose of this study was to investigate the effect of early postoperative
intravenous (IV) iron supplementation in different types of total knee arthroplasty
(TKA) surgery. We retrospectively analyzed 863 patients who underwent TKA between
September 2017 and September 2021. The IV iron (I) and non-IV iron (NI) groups were
compared. Hemoglobin responders, defined as patients who showed a change in hemoglobin
level of ≥2 g/dL at 6 weeks of surgery compared to the baseline immediate postoperative
hemoglobin level, were identified and they were compared with the nonresponders. After
logistic regression analysis, the patients were classified according to the type of
surgery (unilateral TKA, staged bilateral TKA, and simultaneous bilateral TKA). A
subgroup analysis was performed according to the comorbidity as Charlson Comorbidity
Index (CCI). The type of surgery and the rate of hemoglobin responders differed between
the I and NI groups. The surgery type and iron supplementation significantly affected
the hemoglobin responder in the logistic regression model. In each surgery type, hemoglobin
drop in the I group was generally lower in the second and sixth weeks than that in
the NI group. It was also effective in reducing hemoglobin drop on the first day of
the second surgery in staged bilateral TKA. In addition, the number of hospital days
was lower in the IV iron supplementation group who underwent a staged bilateral TKA.
CCI did not affect hemoglobin responder, hemoglobin drop, and transfusion rate in
both the I and NI groups. Postoperative IV iron supplementation affected the outcome
of hemoglobin responders. In addition, it reduced early postoperative hemoglobin drop.
However, iron supplementation did not affect the transfusion rate, complications,
and clinical outcome, regardless of the type of surgery.
Level of evidence Level III, case-control study.
Keywords
knee - total knee arthroplasty - hemoglobin - iron supplementation - surgery type
- hemoglobin responder
