Obesity does not increase blood loss or incidence of immediate postoperative complications during simultaneous total knee arthroplasty: A multicenter study

Blood Transfusion in the Age of Tranexamic Acid: Who Needs a Type and Screen Before Total Hip Arthroplasty?

BACKGROUND

Modern surgical protocols, particularly the use of tranexamic acid (TXA), have reduced, but not eliminated, blood transfusions surrounding total hip arthroplasty (THA). Identifying patients at risk for transfusion remains important for risk reduction and to determine type and screen testing.

METHODS

We reviewed 6,405 patients who underwent primary, unilateral THA between January 2014 and January 2023 at a single academic institution, received TXA, and had preoperative hemoglobin (Hgb) values. We compared demographics, baseline Hgb levels, and surgical details between patients who were and were not transfused. Data were analyzed utilizing multivariate regression and receiver operating characteristic curve analysis.

RESULTS

The overall perioperative and intraoperative transfusion rates were 3.4 and 1.0%, respectively. Patients who were older, women, and American Society of Anesthesiologists class >II demonstrated an increased risk of transfusion. Risk of transfusion demonstrated an inverse correlation with preoperative Hgb levels, a bimodal association with body mass index, and a direct correlation with age, surgical time, and estimated blood loss on multivariate analysis. The receiver operating characteristic analysis demonstrated a preoperative Hgb cutoff of 12 g/dL for predicting any transfusion. Above the threshold of 12 g/dL, total and intraoperative transfusions were rare, with rates of 1.7 and 0.3%, respectively. Total and intraoperative transfusion rates with Hgb between 11 and 12 g/dL were 14.3 and 4.6%, respectively. Below 11 g/dL, total and intraoperative transfusion rates were 27.5 and 10.1%, respectively.

CONCLUSIONS

In the age of TXA, blood transfusion is rare in THA when preoperative Hgb is >12 g/dL, challenging the need for universal type and screening. Conversely, patients who have Hgb < 11.0 g/dL, remain at substantial risk for transfusion. Between Hgb 11 and 12 g/dL, patient age, sex, body mass index, American Society of Anesthesiologists classification, anticipated estimated blood loss, and surgical time may help predict transfusion risk and the need for a perioperative type and screen.

LEVEL OF EVIDENCE

III.

Comparison of bilateral cementless total knee arthroplasty results between patients in different BMI groups

INTRODUCTION

The aim of this study was to compare the results of cementless bilateral total knee arthroplasty (TKA) between individuals in different obesity groups.

MATERIALS AND METHODS

This was a retrospective cohort study. Patients with a body mass index (BMI) greater than 25 who underwent bilateral TKA for gonarthrosis between 2014 and 2020 and completed a minimum follow-up of 24 months were included. Age, sex, height, weight, BMI, operation time, length of stay, patient satisfaction, knee scores and complications were compared. Patients with missing data, who were followed for less than 24 months or had postoperative fractures around the knee were excluded.

RESULTS

There was a significant difference between the groups in terms of operation time (Class III > overweight > Class II > Class I p < 0.001). There was a significant difference in complications between the groups (Class III > Class I > Class II > overweight p = 0.010). According to our pairwise comparison, complications were more common in the class III group than in the overweight group. Knee score (KS) and function score (FS) increased significantly after surgery in all groups (p < 0.001), with no difference in FS (p = 0.448). Knee score changes were greater in the overweight and class I groups (p < 0.001). There was a significant interaction between both KS and FS and person satisfaction (p < 0.001).

CONCLUSION

Cementless TKA improved KS and FS in all obesity groups, yielded high patient satisfaction. Although the incidence of complications was higher in the morbidly obese patients than in the overweight patients, the difference was not significant. Patients with morbid obesity should be informed about related risks before planning cementless TKA.

Influencing factors of hidden blood loss after primary total hip arthroplasty through the posterior approach: a retrospective study

BACKGROUND

Total hip arthroplasty (THA) is an excellent treatment for the end-stage hip disease, and perioperative blood management strategies have been effectively applied to this procedure. However, many patients still experience anemia after the operation, which is usually overlooked by orthopedic surgeons due to the hidden blood loss (HBL) in the perioperative period. Therefore, the objective of this study was to evaluate HBL in patients undergoing primary THA using the posterior approach and to explore its influencing factors.

METHODS

A retrospective analysis of 707 patients who underwent primary THA through the posterior approach was conducted in our hospital from January 2020 to January 2022. By applying Gross's and Nadler's formula, the HBL was calculated. Six quantitative variables (age, body mass index, surgical duration, albumin loss, preoperative hemoglobin, and hemoglobin loss) as well as four qualitative variables (gender, American Society of Anesthesiologists class, major preoperative diagnosis, and hypertension) of patients were analyzed using multivariate linear regression.

RESULTS

The HBL was recorded at 700.39 ± 368.59 mL. As a result of multivariate linear regression analysis, it was determined that body mass index, surgical duration, and hemoglobin loss were all significant risk factors for HBL, whereas preoperative hemoglobin was considered a protective factor. It has been demonstrated that HBL is not significantly correlated with age, albumin loss, gender, ASA class, or major preoperative diagnosis, but it also did not differ from HBL by hypertension.

CONCLUSIONS

Hidden blood Loss (HBL) in patients after primary total hip arthroplasty (THA) using the posterior approach is large and significant. When optimizing the perioperative management of THA, orthopedic surgeons should keep in mind HBL and its influencing factors, especially for patients with high body mass indexes, long surgical durations, and low preoperative hemoglobin levels.

TRIAL REGISTRATION

This study was registered in the Chinese Clinical Trial Registry (ChiCTR2100053888) in 02/12/2021, http://www.chictr.org.cn .

Obesity paradox among patients undergoing total knee arthroplasty: a retrospective cohort study

BACKGROUND

Obesity has been recognized as the risk factor for postoperative complication for surgical patients. However, recent studies have showed protective effect of obesity in surgical and non-surgical patients. Our study is to examine the association of body mass index(BMI) with early postoperative complications in patients undergoing total knee arthroplasty.

MATERIALS AND METHODS

All patients who had primary total knee arthroplasty between January 2014 and December 2019 were included. Medical records were retrospectively reviewed and BMI was categorized as underweight(BMI < 18.5), normal weight(18.5 < BMI < 24.9), overweight I(25 < BMI < 27.4), overweight II(27.5 < BMI < 29.9), obese I(30 < BMI < 34.9) and obese II(BMI ≥ 35). The association between BMI and occurrence of early postoperative complications was examined and logistic regression was used to calculate relationship between BMI and early postoperative complications.

RESULTS

A total of 2969 patients were included in our analysis. The overall complication rate in patients undergoing total knee arthroplasty was 14.8%, with the highest complication being 22.2% in the underweight group, the second highest in the normal weight group(17.5%), the lowest in the overweight I(13.8%) and obese I(12.0%) group and then higher again in obese II group(16.7%). In multivariable analyses, overweight I (OR 0.737, 95% CI 0.559-0.972, P = 0.031) and obese I (OR 0.631, 95% CI 0.449-0.885, P = 0.008) were associated with lower risk of early postoperative complications after total knee arthroplasty.

CONCLUSION

In this retrospective study, overweight and obese patients had a lower risk of early postoperative complications after total knee arthroplasty. Further studies are necessary to confirm and investigate the mechanism of obesity paradox in this surgical population.

TRIAL REGISTRATION

This study had been registrated in www.chictr.org.cn on 25/10/2021 and the registration ID was ChiCTR2100052408.

The effect of body mass index on blood loss and complications in simultaneous bilateral total hip arthroplasty: A multicenter retrospective study

BACKGROUND

The effect of body mass index (BMI) on blood loss in simultaneous bilateral total hip arthroplasty (SBTHA) was still undetermined. The purpose of the study was to evaluate the blood loss, transfusion and incidence of complications in normal, overweight, and obese patients undergoing SBTHA.

METHODS

A total of 344 patients following SBTHA were enrolled into this study. The patients were assigned into three groups on the basis of their BMI, including normal (BMI 18.0-24.9 kg/ m2), overweight (BMI 25.0-29.9 kg/ m2), or obese group (BMI ≥ 30.0 kg/ m2). The primary outcome was total blood loss (TBL), and secondary outcomes were intraoperative blood loss, drain volume, ratio of TBL and patient's blood volume (PBV), transfusion rate and volume, hemoglobin and hematocrit drop, length of stay, expenses, and complications.

RESULTS

The PBV and TBL increased significantly along with the elevated BMI (p < 0.001; p = 0.019, respectively). There was no significant difference in intraoperative blood loss, drain volume, transfusion volume, length of stay, expenses, or incidence of complications among the three groups. In addition, the transfusion rate in normal group was higher than that in overweight (58.3% vs 39.6%, p = 0.001) and obese group (58.3% vs 31.9%, p = 0.001). The maximum hemoglobin drop in obese group was the highest (p = 0.001).

CONCLUSION

Obesity could increase perioperative blood loss but not increase transfusion risk in the setting of SBTHA. Conversely, obese and overweight patients maybe have lower transfusion need compared with normal patients because of more blood volume. In addition, obesity did not affect the incidence of complications.

Can obese patients undergo simultaneous bilateral total knee arthroplasty without an increased risk of perioperative complications?

Simultaneous bilateral total knee arthroplasty (simBTKA) remains controversial, especially in obese patients. Therefore, this retrospective study compared six month perioperative complications in 313 simBTKA patients. Comparison groups included 139 non-obese patients (BMI < 30), 61 obese patients (BMI = 30-35) and 48 severely obese patients (BMI > 35). Increased BMI was associated with longer tourniquet and surgical times (p < 0.001). However, no differences were found for transfusion (p = 0.288), deep infection (p = 0.971), pulmonary embolism (p = 0.454), or deep vein thrombosis (p = 0.670). Increased BMI was, therefore, not associated with greater post-operative complications and should not necessarily contraindicate simBTKA.

The Association between High Body Mass Index and Early Clinical Outcomes in Patients with Proximal Femur Fractures

BACKGROUND

Fractures of the proximal femur constitute daily work in orthopedic trauma surgery. With the continuous increase of obesity in the general population, surgeons face several known technical challenges. The aim of this study was to investigate the association of high body mass index (BMI) in patients with proximal femur fractures with intra- and postoperative adverse events, as well as with functional outcomes after successful surgery.

METHODS

In this retrospective, single-center cohort study, 950 patients who sustained a fracture of the proximal femur (femoral neck fracture or trochanteric fracture) and underwent surgical treatment at our level I trauma center between 2003 and 2015 were included. Patient-specific data were obtained in regard to demographics, comorbidities, and fracture morphology. In-hospital postoperative complications (i.e., need for revision surgery, wound site infection, pneumonia, urinary tract infection, necessary transfusion, and deep-vein thrombosis) were analyzed, along with the length of hospitalization and overall mortality rate. Functional outcome was assessed using the Barthel index and the patient's ability to walk on crutches. Mortality rate and need for revision surgery were assessed over a two-year time period. Any adverse event was correlated to one of the four WHO's BMI groups.

RESULTS

The cohort included 80 (8.4%) underweight patients, 570 (60.0%) normal weight patients, 241 (25.4%) overweight patients, and 59 (6.2%) obese patients. We found more femoral neck fractures (506, or 53%) than trochanteric fractures (444, or 47%). In bivariate analysis, no significant difference was found in regard to overall mortality or postoperative complications. Hospitalization time (LOS) differed between the underweight (12.3 ± 4.8 days), normal (13.6 ± 7.8 days), overweight (14.2 ± 11.7 days), and obese patients (16.0 ± 9.7 days) (p = 0.040). Operation time increased stepwise with increasing BMI: underweight = 85.3 ± 42.9 min; normal weight = 90.2 ± 38.2 min; overweight = 99.9 ± 39.9 min; obese = 117.2 ± 61.5 min (p < 0.001). No significant difference was found by analyzing functional outcomes. However, patients with intermediate BMI levels (18.5-30 kg/m2) tended to achieve the best results, as represented by a higher Barthel index score and the patient's ability to walk on crutches.

CONCLUSION

Increased BMI in patients with proximal femur fractures is associated with both longer operation time and length of hospitalization (LOS). Postoperative mobilization and functional outcomes appear to follow a reversed J-curve distribution (with overweight patients showing the best functional results), whereas both obese and underweight patients have associated poorer function.

Impact of body mass index on hemoglobin level and blood transfusion in total knee arthroplasty: A retrospective case control study

Background

Morbid obesity is a challenge in cases that require total knee arthroplasty, and several studies considered it a contraindication for the procedure due to associated risk of complications, including plummeting hemoglobin levels and subsequent need for a blood transfusion. This study investigated risk factors for blood transfusion in this patient group and considered their relationship to obesity.

Materials and methods

Patients' data were extracted from medical records, including estimated blood loss and perioperative hemoglobin levels. Patients were weighed and measured, and their body mass index (BMI) was calculated and stratified according to international criteria.

Results

A total of 188 patients were included in this study; among them, 136 patients had obesity (72%), with a mean BMI of 33.54. The mean volume of blood lost was 1055.4 ml, with the mean postoperative hemoglobin decrease of 1.42 g/dl and 2.88 g/dl at 6 and 24 h after surgery, respectively. The pre-operative Hb level was the only significant risk factor for blood transfusion. BMI did not affect the risk of blood transfusion or amount of blood lost.

Conclusion

Obesity (BMI > 30 kg/m²) did not increase the risk of needing a blood transfusion after total knee arthroplasty. A judicious transfusion strategy involving the pre-operative Hb optimization should be adopted in TKA to decrease transfusion rate, benefit patient outcomes, and increase healthcare system efficiency. This study shows that high BMI is not a risk factor for postoperative blood transfusion.