ABSTRACT
Objective
To explore the clinical effect of predeposit, salvage, and hemodilution autotransfusion on patients with femoral shaft fracture (FSF) surgery.
Methods
Selected patients with FSF were randomly divided into three groups: intraoperative blood salvage autotransfusion, preoperative hemodilution autohemotransfusion, and predeposit autotransfusion. Five days after the operation, the body temperature, heart rate, blood platelet (PLT), and hemoglobin (Hb) of patients were determined. The concentrations of EPO and GM‐CSF in the three groups were calculated by ELISA. The content of CD14+ monocytes was calculated by FCM assay. The growth time and condition of the patient's callus were determined at the 30th, 45th, and 60th day after operation. Cox regression analysis was used to analyze the correlation between EPO, GM‐CSF, CD14+ mononuclear content, callus growth, and autotransfusion methods.
Results
There were no statistically significant differences in body temperature and heart rate between the three groups (p > 0.05). PLT and Hb in the Predeposit group were markedly increased compared with that in the Salvage and Hemodilution groups. The concentrations of EPO and GM‐CSF in the Predeposit group were markedly increased compared with that in the Salvage and Hemodilution groups. The content of CD14+ monocytes in the Predeposit group was significantly higher than that in the Salvage and Hemodilution groups. Predeposit autotransfusion promotes callus growth more quickly.
Conclusion
Predeposit autotransfusion promoted the recovery of patients with FSF after the operation more quickly than salvage autotransfusion and hemodilution autotransfusion.
Keywords: autotransfusion, femoral shaft fracture (FSF), hemodilution, predeposit, salvage
To explore the clinical effect of predeposit, salvage, and hemodilution autotransfusion on patients with femoral shaft fracture (FSF) surgery. Selected patients with FSF were randomly divided into three groups: intraoperative blood salvage autotransfusion, preoperative hemodilution autohemotransfusion, and predeposit autotransfusion. Five days after the operation, the body temperature, heart rate, blood platelet (PLT), and hemoglobin (Hb) of patients were determined. The concentrations of EPO and GM‐CSF in the three groups were calculated by ELISA. The content of CD14+ monocytes was calculated by FCM assay. The growth time and condition of the patient's callus were determined at the 30th, 45th, and 60th day after operation. Cox regression analysis was used to analyze the correlation between EPO, GM‐CSF, CD14+ mononuclear content, callus growth, andd autotransfusion methods. There were no statistically significant differences in body temperature and heart rate between the three groups (p > 0.05). PLT and Hb in the Predeposit group were markedly increased compared with that in the Salvage group and the Hemodilution group. The concentrations of EPO and GM‐CSF in the Predeposit group were markedly increased compared with that in the Salvage group and the Hemodilution group. The content of CD14+ monocytes in the Predeposit group was significantly higher than that in the Salvage group and the Hemodilution group. Predeposit autotransfusion promotes callus growth more quickly. The concentrations of EPO and GM‐CSF were positively correlated with callus growth in the three groups, and the content of CD14+ monocytes was not correlated in any of the three groups. Predeposit autotransfusion promoted the recovery of patients with FSF after operation more quickly than salvage autotransfusion and hemodilution autotransfusion.
1. Introduction
Femoral shaft fracture (FSF) is a common disease in orthopedic trauma [1]. With the development of society and the development of the transportation industry, the incidence of FSF has increased [2]. Blood loss in patients with FSF is common, not only in the operative and postoperative stages but also in the early stage after the fracture [3]. Acute blood loss can lead to hemorrhagic anemia. Anemia is an independent risk factor for adverse outcomes in patients with FSF, including an increased risk of death 3 months after surgery and an increased risk of death 1 year after surgery. In addition, anemia is detrimental to the early postoperative functional activities of patients, and even indirectly affects the treatment effect of surgery [4]. Transfusion is a common method to treat anemia in patients with FSF. There are some restricting factors in clinical blood transfusion [3, 5]. Blood supply is insufficient in some countries, costs a lot, and has a bad effect on patients.
Anemia and blood transfusion were associated with adverse outcomes [6]. Researchers continue to explore the best methods to improve patients' clinical outcomes. In recent years, due to the spread of blood transfusion diseases, especially hepatitis and AIDS after transfusion, autotransfusion has risen to an important position [7]. Autotransfusion is a simple, effective, and safe way of transfusion, which is easy to popularize in clinics [8]. Autotransfusion includes predeposit, salvage, and hemodilution. Salvage autotransfusion is a blood transfusion method in which the blood from intraoperative bleeding or postoperative wound drainage is recycled, anticoagulated, filtered, washed, and concentrated by the blood recovery device and then returned to the patient. Predeposit autotransfusion is to collect the patient's blood for preservation and then giving it back to the patient when the patient needs blood transfusion to ensure the use of blood for treatment. Hemodilution autotransfusion is to reduce the concentration of blood cells in a unit volume of blood by supplementing crystal fluid or colloidal fluid after anesthesia and before surgery [9, 10]. In case of the same amount of blood loss, the loss of blood cells is significantly reduced. The researchers believe that the main effects of postoperative blood transfusion on the body are immunosuppression, inflammatory effect, and bone marrow hematopoiesis.
This study focused on the transfusion of patients with FSF after surgery. The clinical recovery characteristics of patients were compared by three methods: predeposit transfusion, salvage transfusion, and hemodilution transfusion, including the stable recovery time of vital signs, and callus growth at the 30th, 45th, and 60th day after the operation site. In addition, hematopoietic‐related factors erythropoietin (EPO) and GM‐CSF of the patients were analyzed, and the proportion of CD14+ monocytes in the patients was analyzed.
2. Materials and Methods
2.1. Patients and Grouping
A total of 60 patients with FSF requiring surgery were recruited from Shanghai Gongli Hospital, Naval Military Medical University, from April 2018 to May 2020. The inclusion criteria for patients with FSF were as follows: patients undergoing elective orthopedic surgery, ASAI‐II grade, male, age from 20 to 50 years old, estimated operative blood loss > 600 mL, preoperative hemoglobin (Hb) ≥ 110 g/L, hematocrit (Hct) ≥ 35%, and platelet (PLT) count ≥ 100 × 109/L. The exclusion criteria were as follows: the patient who was suffering from malignant tumor, abnormal blood coagulation before operation, accompanied by cerebrovascular disease, venous thrombosis of lower limbs before operation, abnormal function of the heart, liver, kidney, lung, and other important organ systems.
The selected 60 patients with FSF were randomly divided into three groups: Predeposit, Salvage, and Hemodilution. Within three to seven days after surgery, daily measurements or blood analysis are taken to assess the patient's physical recovery (body temperature, heart rate, platelet count, and Hb count); levels of EPO and granulocyte–macrophage colony‐stimulating factor (GM‐CSF) in the patient's blood were determined by ELISA; the levels of CD14+ monocytes in the blood of the patients were analyzed by flow cytometry (FCM). Follow‐up visits were conducted at 30th, 45th, and 60th day after the operation to analyze the growth time and condition of callus. Callus formation was evaluated using X‐ray and the modified Radiographic Union Score for Tibia.
2.2. ELISA
Due to the availability of material, the levels of EPO and GM‐CSF were measured by ELISA in undiluted plasma samples. Commercially available ELISA kits for EPO and GM‐CSF (BD Biosciences, San Jose, CA) were applied based on the manufacturers' instructions. Results were read at an optical density of 450 nm using a Spectra Max Plus plate reader (Molecular Devices, Sunnyvale, CA). Measurements were performed in duplicate, and p‐values were computed using the two‐sided Student t‐test (p < 0.05).
2.3. FCM
The content of CD14+ monocytes in the blood of patients was determined by FCM. A tube was taken as the control by adding CD14‐FITC and Mouse‐IgG1‐APC, and the other tube was added with CD14‐FITC and TLR2‐APC. After mixing, tubes were stored at 4°C for 20 min in the dark, and then 2 mL erythrocyte lysate was added, mixed well, and kept at room temperature for 10 min. Lysate was centrifuged at 1500 rpm for 7 min, and the sediment was washed by PBS. At last, PBS was added and the solution was mixed fully. BD FACSAria flow cytometry was used for detection. The relative content of CD14+ was expressed by the mean fluorescence index.
2.4. Statistical Analysis
Logistic multifactor regression analysis was used to analyze the correlation between EPO, GM‐CSF, content of CD14+ mononuclear cells, callus growth, and blood transfusion mode. All statistical tests were two‐sided, and statistical significance was defined as p < 0.05.
3. Results
3.1. Autotransfusion Methods Affect Body Recovery of Patients
The observed indicators for patient's physical recovery, including body temperature, heart rate, blood PLT, and Hb, were determined after the operation for 5 days. As shown in Table 1, there were no statistically significant differences in body temperature and heart rate between groups (p > 0.05). PLT and Hb in the Predeposit group were markedly increased compared with that in the Salvage and Hemodilution groups (p < 0.05). Those indicated Predeposit autotransfusion was the most conducive to the recovery of various indicators.
TABLE 1.
Observed indicators of patients in three groups after operation for 5 days.
| Method | Temperature (°C) | Heart rate (bpm) | PLT (×109/L) | Hb (g/L) |
|---|---|---|---|---|
| Salvage | 36.90 | 91.23 | 146.36 | 96.04 |
| Hemodilution | 36.84 | 91.62 | 145.24 | 98.52 |
| Predeposit | 36.87 | 90.02 | 154.88 | 107.34 |
3.2. Predeposit Autotransfusion Increases the Content of EPO and GM‐CSF
The concentrations of EPO and GM‐CSF in the Predeposit, Salvage, and Hemodilution groups were calculated by ELISA. Results are shown in Figure 1. The concentrations of EPO and GM‐CSF in the Predeposit group were markedly increased compared with that in the Salvage and Hemodilution groups (p < 0.01). Moreover, there were no significant differences in EPO and GM‐CSF concentrations between the Salvage and Hemodilution groups (p > 0.05).
FIGURE 1.
Concentrations of EPO and GM‐CSF in the Predeposit, Salvage, and Hemodilution groups were calculated by ELISA. **p < 0.01 versus the Salvage group, that indicating the difference has statistical significance; ## p < 0.01 versus the Hemodilution group, that indicating the difference has statistical significance.
3.3. Determination on the Content of CD14+ Monocytes
The content of CD14+ monocytes in the Predeposit, Salvage and Hemodilution groups was calculated by FCM assay. As shown in Figure 2, the content of CD14+ monocytes in the Salvage group was 35.1%, in the Hemodilution group was 40.7%, and in the Predeposit group was 57.3%. The differences in content between the Hemodilution group and the Predeposit group, and the Salvage group and the Predeposit group were statistically significant (p < 0.01), whereas the difference between the Hemodilution group and the Salvage group was not statistically significant (p > 0.05).
FIGURE 2.
Contents of CD14+ monocytes in the Predeposit, Salvage, and Hemodilution groups were determined by flow cytometry assay. **p < 0.01 versus the Salvage group, indicating that the difference has statistical significance; ## p < 0.01 versus the Hemodilution group, indicating that the difference has statistical significance.
3.4. Predeposit Transfusion Promotes Callus Growth More
The growth time and condition of the patient's callus were determined at the 30th, 45th, and 60th day after operation. Results are shown in Table 2. The callus in the Salvage group and the Hemodilution group at the 30th day was 0 mm, while the callus in the Predeposit group was 2–3 mm. At the 45th day, callus in the Salvage group, the Hemodilution group, and the Predeposit group was 2–5, 2–4, and 3–6 mm, respectively. At the 60th day, callus in the Salvage, Hemodilution, and Predeposit groups was 5–8, 5–6, and 6–10 mm, respectively. Those indicated predeposit transfusion promotes callus growth more quickly.
TABLE 2.
Growth time and condition of the patient's callus in three groups.
| Method | 30 days (mm) | 45 days (mm) | 60 days (mm) |
|---|---|---|---|
| Salvage | 0 | 2–5 | 5–8 |
| Hemodilution | 0 | 2–4 | 5–6 |
| Predeposit | 2–3 | 3–6 | 6–10 |
3.5. Correlation Analysis
Logistic multifactor regression analysis was used to analyze the correlation between EPO, GM‐CSF, CD14+ mononuclear content, callus growth, and transfusion methods to evaluate the advantages and disadvantages of the three transfusion methods. Results are shown in Tables 3 and 4. As shown, the concentrations of EPO and GM‐CSF were positively correlated with callus growth in the three groups, and they had a significant relationship with predeposit transfusion. In addition, the content of CD14+ monocytes was not correlated in any of the three groups.
TABLE 3.
Relevance between EPO, GM‐CSF, and callus growth.
| χ 2 | p value | OR | 95% CI | |
|---|---|---|---|---|
| EPO | 4.975 | 0.001 | 0.315 | 1.023, 3.152 |
| GM‐CSF | 5.064 | 0.022 | 1.217 | 1.082, 3.534 |
TABLE 4.
Relevance between EPO, GM‐CSF, CD14+ mononuclear content, and transfusion methods.
| Method | χ 2 | p value | OR | 95% CI |
|---|---|---|---|---|
| EPO | 3.278 | 0.015 | 1.954 | 1.080, 3.489 |
| GM‐CSF | 4.272 | 0.021 | 2.573 | 1.286, 6.830 |
| CD14+ | 0.521 | 0.106 | 0.956 | 0.628, 1.854 |
4. Discussion
In recent years, the increasing number of orthopedic surgery patients has further increased the demand for blood. At present, allogeneic transfusion is mainly used to supplement patients' blood in orthopedic surgery, but allogeneic transfusion should consider the condition of blood‐borne diseases and the shortage of blood resources [11]. Autotransfusion can not only avoid the side effect of allogeneic transfusion and eliminate the risk of disease transmission but also stimulate the hematopoietic function of bone marrow so that the hematopoietic speed of patients after surgery is accelerated [12, 13]. Autotransfusion not only alleviates the shortage of blood source but also saves the medical expenses of patients, which is a safe and effective method [14]. Hemodilution transfusion can solve the problem of blood supply for patients with rare blood type [15]. Salvage transfusion can supply fully compatible blood of the same type.
Our study showed that PLT and Hb in the Predeposit group were markedly increased compared with those in the Salvage and Hemodilution groups, which indicated Predeposit transfusion was the most conducive to the recovery of various indicators. Platelets contain a variety of autologous growth factors, including platelet‐derived growth factor, insulin‐like growth factor, and growth factor for hepatocytes [16]. Hypoxemia has been recognized as a risk factor for bone loss [17]. It predicts long‐term survival in dialysis patients [18]. Then, we calculated the concentrations of EPO and GM‐CSF in the Predeposit, Salvage, and Hemodilution groups by ELISA. The results showed that the concentrations of EPO and GM‐CSF in the Predeposit group were markedly increased compared with those in the Salvage and Hemodilution groups. EPO is a hormone that stimulates the production of new red blood cells [19]. It can regulate the proliferation and differentiation of erythroid cells [20]. It is tissue protective in preclinical models of ischemic, traumatic, toxic, and inflammatory injuries [21]. It has been demonstrated to stimulate fracture healing [22]. GM‐CSF is a powerful growth and differentiation factor that acts on hematopoietic progenitor cells and also activates differentiated granulocytes and macrophages [23]. It can govern the functions of granulocyte and macrophage lineage populations at all stages of maturation [24]. The results of FCM showed that the content of CD14+ monocytes in the Storage group was markedly higher than that in the Salvage and Hemodilution groups. Human CD14+ monocytes can differentiate between monocyte‐derived macrophages or dendritic cells upon suitable stimulation [25]. Moreover, our study also found that predeposit autotransfusion promotes callus growth more quickly than salvage and hemodilution autotransfusion. Fracture healing presents a sequence of three major stages: inflammation and granulation tissue formation, callus formation, and remodeling [26]. Callus formation and growth are an essential part of secondary fracture healing [27]. Cox regression analysis also showed that the concentrations of EPO and GM‐CSF were positively correlated with callus growth in the three groups, and they had a significant relationship with predeposit autotransfusion.
We acknowledge that not accounting for previous conditions such as anemia, thalassemia, or other underlying diseases as potential confounding factors is a limitation of the current study.
In conclusion, predeposit autotransfusion promoted the recovery of patients with FSF after operation more quickly than salvage autotransfusion and hemodilution autotransfusion, indicating that predeposit autotransfusion is more suitable for patients with FSF.
Author Contributions
Each author has made an important scientific contribution to the study and has assisted with the drafting or revising of the manuscript.
Ethics Statement
Ethics approval was given by the Shanghai Gongli Hospital, Naval Military Medical University, and written informed consent was obtained from all patients.
Consent
All authors have consented to publish this research.
Conflicts of Interest
The authors declare no conflicts of interest.
Acknowledgments
We would like to acknowledge those who made helpful contributions to this paper.
Yujia Wang, Huan Wang, and Jiaming Xu contributed equally to this work.
Funding: This work was supported by the Key Disciplines Group Construction Project of the Pudong Health Bureau of Shanghai (Grant PWZxq2022‐5).
Data Availability Statement
The data are free to access and available upon request.
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Associated Data
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Data Availability Statement
The data are free to access and available upon request.