Clinical experience with tranexamic acid during primary total hip arthroplasty

Patient-Adaptive Population-Based Modeling of Arterial Input Functions

Kinetic modeling of dynamic PET data requires knowledge of tracer concentration in blood plasma, described by the arterial input function (AIF). Arterial blood sampling is the gold standard for AIF measurement, but is invasive and labour intensive. A number of methods have been proposed to accurately estimate the AIF directly from blood sampling and/or imaging data. Here we consider fitting a patient-adaptive mixture of historical population time course profiles to estimate individual AIFs. Travel time of a tracer atom from the injection site to the right ventricle of the heart is modeled as a realization from a Gamma distribution, and the time this atom spends in circulation before being sampled is represented by a subject-specific linear mixture of population profiles. These functions are estimated from independent population data. Individual AIFs are obtained by projection onto this basis of population profile components. The model incorporates knowledge of injection duration into the fit, allowing for varying injection protocols. Analyses of arterial sampling data from 18F-FDG, 15O-H2O and 18F-FLT clinical studies show that the proposed model can outperform reference techniques. The statistically significant gain achieved by using population data to train the basis components, instead of fitting these from the single individual sampling data, is measured on the FDG cohort. Kinetic analyses of simulated data demonstrate the reliability and potential benefit of this approach in estimating physiological parameters. These results are further supported by numerical simulations that demonstrate convergence and stability of the proposed technique under varying training population sizes and noise levels.

Hip resurfacing and posterior approach total hip arthroplasty have equivalent blood loss when tranexamic acid is used: a propensity score matched cohort analysis

INTRODUCTION

Hip resurfacing (HR) requires a larger approach and soft tissue dissection and might therefore be associated with increased blood loss compared to total hip arthroplasty (THA). However, the effect of the adoption of tranexamic acid (TXA) in this setting is unknown. Therefore, the current study compares the blood loss and transfusion requirements between HR and posterior THA in patients receiving TXA.

MATERIALS AND METHODS

This retrospective cohort study included patients undergoing primary, unilateral THA or HR using a posterior approach between February 2016 and 2020 in which TXA was administered. THA and HR patients were propensity score matched using nearest neighbor greedy matching accounting for demographic, health and surgical variables. Postoperative hemoglobin (Hgb) levels and Hgb drop from preoperative to post-operative day (POD) 1 were compared using t-tests and associated risk factors were assessed using linear mixed modelling.

RESULTS

After matching, each cohort consisted of 1395 patients. Cohorts were similar regarding age, sex, BMI, and Charlson Comorbidity Index. No significant differences were found for Hgb levels on POD 1 (12.3 g/dl; p = 0.90) or Hgb drop (2.3 g/dl; p = 0.87). Duration of surgery was significantly longer for HR patients (82 vs 77 min; p < 0.01). Transfusion rate was 0.1% in both cohorts (p = 1.00). Hospital stay was significantly shorter for HR patients (1 vs 2 days; p < 0.01).

CONCLUSION

HR using a standard TXA regimen is not associated with greater perioperative blood loss than posterior THA and does not result in increased transfusion requirements. Both surgical procedures can be considered equally safe in terms of perioperative blood management when TXA is used.

Blood Management Following Total Joint Arthroplasty in an Aging Population: Can We Do Better?

BACKGROUND

To evaluate the transfusion rates for octogenarians and nonagenarians following total knee and hip arthroplasty (TKA, THA), we compared transfusion rates and associated risk factors among sexagenarians, septuagenarians, octogenarians, and nonagenarians.

METHODS

This retrospective cohort study included 13,603 sexagenarians, 9796 septuagenarians, 2706 octogenarians, and 158 nonagenarians that received a primary, unilateral THA or TKA between 2016 and 2020 at a high-volume institution. Using multivariable logistic regression analysis, the study analyzed risk factors for postoperative transfusions including use of tranexamic acid (TXA) and compared preoperative and postoperative hemoglobin (Hgb) levels and the drop in Hgb.

RESULTS

Nonagenarians had significantly higher transfusion rates (THA 25.5%, TKA 26.7%) than octogenarians (THA 9.9%, TKA 9.2%), septuagenarians (THA 3.3%, TKA 4.5%), and sexagenarians (THA 1.9%, TKA 2.9%) (P < .01). Significant risk factors for transfusion requirement following THA were American Society of Anesthesiologists level III (odds ratio [OR] 5.3, P < .01) and American Society of Anesthesiologists level IV (OR 8.0, P = .01), nonuse of TXA (intravenous: OR 0.3, P < .01; topical: OR 0.5, P < .01), lower preoperative Hgb levels (OR 0.4, P < .01), longer duration of surgery (OR 1.0, P < .01), and hepatopathy (OR 3.1, P < .01). Significant risk factors following TKA were nonuse of TXA (intravenous: OR 0.3, P < .01; topical: OR 0.5, P < .01; combined: OR 0.2, P < .01), lower preoperative Hgb levels (OR 0.4, P < .01), and longer surgery time (OR 1.0, P < .01).

CONCLUSION

The strongest independent risk factors for increased transfusion rates among octogenarians and nonagenarians were lack of TXA application and lower preoperative Hgb levels. Routine TXA application and preoperative patient optimization are recommended to reduce transfusion rates in patients aged 80+.

One Dose Versus Two Doses of Intravenous Tranexamic Acid in Total Joint Arthroplasty

INTRODUCTION

Despite its widespread use, a single formulation or dosing regimen of tranexamic acid (TXA) has not been universally agreed on for total joint arthroplasty. The purpose of this study is to compare previously uninvestigated single-dose and two-dose regimens in postoperative hemoglobin level and secondary outcomes within 30 days of surgery.

METHODS

A retrospective search of our institution's database of patients who underwent primary total knee arthroplasty and primary total hip arthroplasty between January 1, 2017, and July 1, 2019, was performed. Patients were divided into two groups: one group received a 1-g bolus of intravenous TXA just before incision and another intravenous 1-g bolus during wound closure, and the second group received a single 1-g intravenous bolus of TXA just before incision. Two doses of TXA were administered in 873 procedures, and a single dose was administered in 647 procedures.

RESULTS

A single intravenous TXA dose just before incision was comparable with using two doses of intravenous TXA on patients' postoperative hemoglobin value, length of stay, rate of transfusion, and 30-day postoperative complication rate, although those receiving two doses of TXA trended toward being less likely to require a transfusion (odds ratio = 0.561; 95% confidence interval: 0.296 to 1.062; P = 0.08). A sensitivity analysis was unable to identify a preoperative hemoglobin value that would identify whether patients would benefit from two versus one dose of TXA.

DISCUSSION

The use of a single intravenous TXA dose was as efficacious as two doses, without an increase in postoperative complications. Further studies may identify patient subgroups that would benefit from a second dose.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Tranexamic acid administration to older patients undergoing primary total hip arthroplasty conserves hemoglobin and reduces blood loss

BACKGROUND

Tranexamic acid effects in older people are difficult to predict. This study investigated the following research questions: 1) Is tranexamic acid effective in older patients undergoing primary total hip arthroplasty (THA)? and 2) Is there a difference in the effect of tranexamic acid between younger and older patients?

METHODS

This was a 2-phase retrospective matched-pair study of patients who underwent THA in 2007-2013. All procedures were performed by surgeons with at least 10 years' experience as senior consultant. In the first phase, 58 patients aged 65 years or more who received tranexamic acid were matched 1:1 with patients who did not receive tranexamic acid for age, sex, American Society of Anesthesiologists (ASA) classification and body mass index. In the second phase, 58 patients aged 65 years or more who received tranexamic acid were matched 1:1 with patients less than 65 years of age who received tranexamic acid for sex, ASA classification and body mass index. The primary outcome measures were percent maximum decrease in hemoglobin level and estimated blood loss after surgery.

RESULTS

In the first phase, patients who received tranexamic acid conserved postoperative hemoglobin by a mean of 10.26 g/L (standard deviation [SD] 9.89 g/L) compared to the control group (p < 0.001). The mean difference in the estimated perioperative blood loss between the 2 groups was 410 mL (SD 376 mL) (p < 0.001), which indicated less bleeding in the treatment group. In the second phase, there was no difference between the younger (mean age 55.1 [SD 7.28] yr) and older (mean age 75.6 [SD 6.35] yr) groups in mean lowest postoperative hemoglobin level or percent decrease in hemoglobin level.

CONCLUSION

Tranexamic acid reduced the postoperative decrease in hemoglobin level and blood loss in older patients. Moreover, the significant hemoglobin-sparing effect of tranexamic acid in older patients was similar to that observed in younger patients.

An Evaluation of the Safety and Effectiveness of Total Hip Arthroplasty as an Outpatient Procedure: A Matched-Cohort Analysis

BACKGROUND

Outpatient hip arthroplasty is being performed more routinely; however, safety remains a concern. The purpose of this study was to compare the rate of adverse events of outpatient total hip arthroplasty (THA) and assess barriers to discharge.

METHODS

We examined 136 patients who underwent unilateral THA by one surgeon and were discharged on the same day of surgery. Using propensity matching, 136 inpatients who received the same procedure, and were discharged on postoperative day one or later, were identified. For each cohort, 90-day occurrence of adverse events, readmissions, and emergency visits were recorded and compared. Adverse events were graded using the OrthoSAVES tool. A secondary objective was to assess potential barriers to same-day discharge.

RESULTS

Within 90 days postoperatively, 12 outpatients (8.82%) and 14 inpatients (10.29%) developed an adverse event. There were no significant differences between the rate or severity of adverse events between the 2 groups and no serious adverse events in either group. In the outpatient group, there was a correlation between the dosage of spinal anesthetic (bupivacaine) given and time required to stay in postanesthetic care unit postoperatively.

CONCLUSION

When comparing the 2 groups, there were no differences in adverse events at 90 days. At our center, in the appropriate patient population, outpatient THA is a safe and cost-effective option. A potential barrier to mobility postoperatively and successful same-day discharge is the time required to stay in postanesthetic care unit postoperatively, which was significantly correlated with an increased dose of spinal anesthetic given in our outpatient cohort.

Pharmacologic Hemostatic Agents in Total Joint Arthroplasty-A Cost-Effectiveness Analysis

BACKGROUND

Total knee and hip arthroplasties can be associated with substantial blood loss, affecting morbidity and even mortality. Two pharmacological antifibrinolytics, ε-aminocaproic acid (EACA) and tranexamic acid (TXA) have been used to minimize perioperative blood loss, but both have associated morbidity. Given the added cost of these medications and the risks associated with then, a cost-effectiveness analysis was undertaken to ascertain the best strategy.

METHODS

A cost-effectiveness model was constructed using the payoffs of cost (in United States dollars) and effectiveness (quality-adjusted life expectancy, in days). The medical literature was used to ascertain various complications, their probabilities, utility values, and direct medical costs associated with various health states. A time horizon of 10 years and a willingness to pay threshold of $100,000 was used.

RESULTS

The total cost and effectiveness (quality-adjusted life expectancy, in days) was $459.77, $951.22, and $1174.87 and 3411.19, 3248.02, and 3342.69 for TXA, no pharmacologic hemostatic agent, and EACA, respectively. Because TXA is less expensive and more effective than the competing alternatives, it was the favored strategy. One-way sensitivity analyses for probability of transfusion and myocardial infarction for all 3 strategies revealed that TXA remains the dominant strategy across all clinically plausible values.

CONCLUSION

TXA, when compared with no pharmacologic hemostatic agent and with EACA, is the most cost-effective strategy to minimize intraoperative blood loss in hip and knee total joint arthroplasties. These findings are robust to sensitivity analyses using clinically plausible probabilities.

Influence of single-dose intravenous tranexamic acid on total hip replacement : A study on transfusions, collateral complications, and readmissions

INTRODUCTION

To determine the effects of tranexamic acid (TXA) on transfusions in patients undergoing hip replacement with a hybrid or cementless prosthesis.

METHODS

A group of 172 consecutive patients aged 18 years or older who underwent elective hip replacement with uncemented or hybrid prostheses, undergoing surgery between January 2012 and January 2014 by the same primary surgeon and anesthesiologist, were retrospectively included. TXA (1 g) was administered immediately before incision in the TXA group. Primary variables included number of red blood cell transfusions and the influence of TXA for each type of prosthesis. Secondary variables included hematocrit at discharge, length of hospital stay, thrombosis or pulmonary embolism, seizures, and death.

RESULTS

Average transfusion was 1.53 units/patient in the control group compared to 0.6 units/patient in the TXA group (z = 6.29; U = 1640.5; p < 0.0001). TXA use was significantly correlated with the number of units transfused (p < 0.0001, 95% CI -1.24 to -0.68). Odds risk reduction for transfusion was observed during surgery (OR: 0.14; CI 0.06-0.29; p < 0.0001) and during the rest of hospital stay (OR: 0.11; CI 0.01-0.96; p = 0.046). Both hybrid and cementless prostheses that received TXA were transfused less than control groups (0.57 ± 1 vs. 1.7 ± 1 p < 0.01 and 0.65 ± 1 vs. 1.24 ± 1 p < 0.01). No difference was observed between the groups regarding adverse effects. Hematocrit values at discharge and length of hospital stay were similar between groups. No deaths were observed during hospital stay.

CONCLUSIONS

TXA reduced transfusions without increasing the prevalence of adverse effects. This reduction was observed during surgery and the following days of hospital stay for both for hybrid and cementless prosthesis.

Efficacy and safety of the topical application of tranexamic acid in primary cementless hip arthroplasty: prospective, randomised, double-blind and controlled study

OBJECTIVE

To evaluate the efficacy of topical tranexamic acid topical in cementless total hip arthroplasty from the point of view of bleeding, transfusion requirements and length of stay, and describe the complications of use compared to a control group.

MATERIAL AND METHODS

A prospective, randomised, double-blinded and controlled study including all patients undergoing cementless total hip arthroplasty in our centre between June 2014 and July 2015. Blood loss was estimated using the formula described by Nadler and Good.

RESULTS

The final analysis included 119 patients. The decrease in haemoglobin after surgery was lower in the tranexamic acid group (3.28±1.13g/dL) than in the controls (4.03±1.27g/dL, P=.001) and estimated blood loss (1,216.75±410.46mL vs. 1,542.12±498.97mL, P<.001), the percentage of transfused patients (35.9% vs. 19.3%, P<.05) and the number of transfused red blood cell units per patient (0.37±0.77 vs. 0.98±1.77; P<.05). There were no differences between groups in the occurrence of complications or length of stay.

CONCLUSIONS

The use of topical tranexamic acid in cementless total hip arthroplasty results in a decrease in bleeding and transfusion requirements without increasing the incidence of complications.

Tranexamic acid

Aims

This study investigated whether the use of tranexamic acid (TXA) decreased blood loss and transfusion related cost following surface replacement arthroplasty (SRA).

Methods

A retrospective review of patients treated with TXA during a SRA, who did not receive autologous blood (TXA group) was performed. Two comparison groups were established; the first group comprised of patients who donated their own blood pre-operatively (auto group) and the second of patients who did not donate blood pre-operatively (control). Outcomes included transfusions, post-operative haemoglobin (Hgb), complications, and length of post-operative stay.

Results

Between 2009 and 2013, 150 patients undergoing SRA were identified for inclusion: 51 in the auto, 49 in the control, and 50 in the TXA group. There were no differences in the pre-operative Hgb concentrations between groups. The mean post-operative Hgb was 11.3 g/dL (9.1 to 13.6) in the auto and TXA groups, and 10.6 g/dL (8.1 to 12.1)in the control group (p = 0.001). Accounting for cost of transfusions, administration of TXA, and length of stay, the cost per patient was $1731, $339, and $185 for the auto, control and TXA groups, respectively.

Discussion

TXA use demonstrated higher post-operative Hgb concentrations when compared with controls and decreased peri-operative costs. Take home message: Tranexamic acid safely limits allogeneic transfusion, maintains post-operative haemoglobin, and decreases direct and indirect transfusion related costs in surface replacement arthroplasty. Cite this article: Bone Joint J 2016;98-B:173–8.