Effect of knee flexion position and combined application of tranexamic acid on blood loss following primary total knee arthroplasty: a prospective randomized controlled trial

Pharmacological interventions for the prevention of bleeding in people undergoing elective hip or knee surgery: a systematic review and network meta-analysis

BACKGROUND

Hip and knee replacement surgery is a well-established means of improving quality of life, but is associated with a significant risk of bleeding. One-third of people are estimated to be anaemic before hip or knee replacement surgery; coupled with the blood lost during surgery, up to 90% of individuals are anaemic postoperatively. As a result, people undergoing orthopaedic surgery receive 3.9% of all packed red blood cell transfusions in the UK. Bleeding and the need for allogeneic blood transfusions has been shown to increase the risk of surgical site infection and mortality, and is associated with an increased duration of hospital stay and costs associated with surgery. Reducing blood loss during surgery may reduce the risk of allogeneic blood transfusion, reduce costs and improve outcomes following surgery. Several pharmacological interventions are available and currently employed as part of routine clinical care.

OBJECTIVES

To determine the relative efficacy of pharmacological interventions for preventing blood loss in elective primary or revision hip or knee replacement, and to identify optimal administration of interventions regarding timing, dose and route, using network meta-analysis (NMA) methodology.

SEARCH METHODS

We searched the following databases for randomised controlled trials (RCTs) and systematic reviews, from inception to 18 October 2022: CENTRAL (the Cochrane Library), MEDLINE (Ovid), Embase (Ovid), CINAHL (EBSCOhost), Transfusion Evidence Library (Evidentia), ClinicalTrials.gov and WHO International Clinical Trials Registry Platform (ICTRP).

SELECTION CRITERIA

We included RCTs of people undergoing elective hip or knee surgery only. We excluded non-elective or emergency procedures, and studies published since 2010 that had not been prospectively registered (Cochrane Injuries policy). There were no restrictions on gender, ethnicity or age (adults only). We excluded studies that used standard of care as the comparator. Eligible interventions included: antifibrinolytics (tranexamic acid (TXA), aprotinin, epsilon-aminocaproic acid (EACA)), desmopressin, factor VIIa and XIII, fibrinogen, fibrin sealants and non-fibrin sealants.

DATA COLLECTION AND ANALYSIS

We performed the review according to standard Cochrane methodology. Two authors independently assessed trial eligibility and risk of bias, and extracted data. We assessed the certainty of the evidence using CINeMA. We presented direct (pairwise) results using RevMan Web and performed the NMA using BUGSnet. We were interested in the following primary outcomes: need for allogenic blood transfusion (up to 30 days) and all-cause mortality (deaths occurring up to 30 days after the operation), and the following secondary outcomes: mean number of transfusion episodes per person (up to 30 days), re-operation due to bleeding (within seven days), length of hospital stay and adverse events related to the intervention received.

MAIN RESULTS

We included a total of 102 studies. Twelve studies did not report the number of included participants; the other 90 studies included 8418 participants. Trials included more women (64%) than men (36%). In the NMA for allogeneic blood transfusion, we included 47 studies (4398 participants). Most studies examined TXA (58 arms, 56%). We found that TXA, given intra-articularly and orally at a total dose of greater than 3 g pre-incision, intraoperatively and postoperatively, ranked the highest, with an anticipated absolute effect of 147 fewer blood transfusions per 1000 people (150 fewer to 104 fewer) (53% chance of ranking 1st) within the NMA (risk ratio (RR) 0.02, 95% credible interval (CrI) 0 to 0.31; moderate-certainty evidence). This was followed by TXA given orally at a total dose of 3 g pre-incision and postoperatively (RR 0.06, 95% CrI 0.00 to 1.34; low-certainty evidence) and TXA given intravenously and orally at a total dose of greater than 3 g intraoperatively and postoperatively (RR 0.10, 95% CrI 0.02 to 0.55; low-certainty evidence). Aprotinin (RR 0.59, 95% CrI 0.36 to 0.96; low-certainty evidence), topical fibrin (RR 0.86, CrI 0.25 to 2.93; very low-certainty evidence) and EACA (RR 0.60, 95% CrI 0.29 to 1.27; very low-certainty evidence) were not shown to be as effective compared with TXA at reducing the risk of blood transfusion. We were unable to perform an NMA for our primary outcome all-cause mortality within 30 days of surgery due to the large number of studies with zero events, or because the outcome was not reported. In the NMA for deep vein thrombosis (DVT), we included 19 studies (2395 participants). Most studies examined TXA (27 arms, 64%). No studies assessed desmopressin, EACA or topical fibrin. We found that TXA given intravenously and orally at a total dose of greater than 3 g intraoperatively and postoperatively ranked the highest, with an anticipated absolute effect of 67 fewer DVTs per 1000 people (67 fewer to 34 more) (26% chance of ranking first) within the NMA (RR 0.16, 95% CrI 0.02 to 1.43; low-certainty evidence). This was followed by TXA given intravenously and intra-articularly at a total dose of 2 g pre-incision and intraoperatively (RR 0.21, 95% CrI 0.00 to 9.12; low-certainty evidence) and TXA given intravenously and intra-articularly, total dose greater than 3 g pre-incision, intraoperatively and postoperatively (RR 0.13, 95% CrI 0.01 to 3.11; low-certainty evidence). Aprotinin was not shown to be as effective compared with TXA (RR 0.67, 95% CrI 0.28 to 1.62; very low-certainty evidence). We were unable to perform an NMA for our secondary outcomes pulmonary embolism, myocardial infarction and CVA (stroke) within 30 days, mean number of transfusion episodes per person (up to 30 days), re-operation due to bleeding (within seven days), or length of hospital stay, due to the large number of studies with zero events, or because the outcome was not reported by enough studies to build a network. There are 30 ongoing trials planning to recruit 3776 participants, the majority examining TXA (26 trials).

AUTHORS' CONCLUSIONS

We found that of all the interventions studied, TXA is probably the most effective intervention for preventing bleeding in people undergoing hip or knee replacement surgery. Aprotinin and EACA may not be as effective as TXA at preventing the need for allogeneic blood transfusion. We were not able to draw strong conclusions on the optimal dose, route and timing of administration of TXA. We found that TXA given at higher doses tended to rank higher in the treatment hierarchy, and we also found that it may be more beneficial to use a mixed route of administration (oral and intra-articular, oral and intravenous, or intravenous and intra-articular). Oral administration may be as effective as intravenous administration of TXA. We found little to no evidence of harm associated with higher doses of tranexamic acid in the risk of DVT. However, we are not able to definitively draw these conclusions based on the trials included within this review.

Effect of an Elevated Preoperative International Normalized Ratio on Transfusion and Complications in Primary Total Hip Arthroplasty with the Enhanced Recovery after Surgery Protocol

Objective

To verify whether an elevated preoperative international normalized ratio (INR) increases transfusion and complications independently in primary total hip arthroplasty (THA) with the management of an enhanced recovery after surgery (EARS) protocol.

Methods

We retrospectively reviewed the database of adults who underwent primary THA between 2014 and 2018 by the same surgeon. A total of 552 patients were assigned into three groups by preoperative INR class: INR ≤ 0.9, 0.9 < INR < 1.0, and INR ≥ 1.0. We regarded transfusion within 90 days during the same hospitalization as the primary outcome. We also included perioperative blood loss, maximum Hb drop, postoperative anaemia requiring medicine, and length of hospital stay (LOS) during the same hospitalization in the study. Complications and reoperation at 90 days and mortality at 90 days and 12 months were also included in the study. Univariable analyses were utilized to compare baselines and outcomes among the three groups. Multivariate logistic regressions were used to adjust for differences at baseline among the groups.

Results

All patients had an INR < 1.5 preoperatively and were managed with the ERAS protocol. Among them, 93 (16.8%) patients had INR ≤ 0.9, 268 (48.6%) patients had 0.9 < INR < 1.0, and 191 (34.6%) patients had INR ≥ 1.0. In the univariable analyses, as the INR increased, the transfusion rates increased from 1.08% for INR ≤ 0.9, to 1.12% for 0.9 < INR < 1.0 and to 5.76% for INR ≥ 1.0 (P < 0.05). The overall complication rate increased from 10.8% for INR ≤ 0.9, to 16.4% for 0.9 < INR < 1.0, and to 22.5% for INR ≥ 1.0 (P < 0.05). The length of stay (LOS) in the INR ≥ 1.0 group was 5.7 ± 2.2 days, which was significantly longer than that in the INR ≤ 0.9 group (4.7 ± 1.6 days, P = 0.000) and 0.9 < INR < 1.0 group (5.1 ± 2.0 days, P = 0.007). No statistical significance was detected among the groups regarding blood loss, maximum Hb drop, or the incidence of postoperative anaemia that required medicine. There was no significant difference in reoperation or mortality among the groups. When controlling for demographic and comorbidity characteristics, there was no statistically significant difference in the odds of transfusion during the same hospitalization or overall complications at 90 days among the groups (P > 0.05).

Conclusions

Elevated preoperative INR cannot increase transfusion or complication rates independently in primary THA with the management of the ERAS protocol. With the improvement in the ERAS protocol and the use of tranexamic acid (TXA), an INR < 1.5 is still a conventional safe threshold for THA surgery.

Early intravenous tranexamic acid intervention reduces post-traumatic hidden blood loss in elderly patients with intertrochanteric fracture: a randomized controlled trial

PURPOSE

Elderly patients with intertrochanteric fractures exhibit post-traumatic hidden blood loss (HBL). This study aimed to evaluate the efficacy and safety of reducing post-traumatic HBL via early intravenous (IV) tranexamic acid (TXA) intervention in elderly patients with intertrochanteric fracture.

METHODS

A prospective randomized controlled study was conducted with 125 patients (age ≥ 65 years, injury time ≤ 6 h) who presented with intertrochanteric fracture from September 2018 and September 2019. Patients in the TXA group (n = 63) received 1 g of IV TXA at admission, whereas those in the normal saline (NS) group (n = 62) received an equal volume of saline. Hemoglobin (Hgb) and hematocrit (Hct) were recorded at post-traumatic admission (PTA) and on post-traumatic days (PTDs) 1-3. HBL was calculated using the Gross formula. Lower extremity venous ultrasound was performed to detect venous thrombosis.

RESULTS

Hgb on PTDs 2 and 3 was statistically higher in the TXA group than in the NS group. Hct and HBL on PTDs 1-3 were significantly less in the TXA group compared to the NS group. Preoperative transfusion rate was significantly lower in the TXA group compared with the NS group. There was no difference between the two groups with regard to the rates of complications.

CONCLUSION

Early IV TXA intervention could reduce post-traumatic HBL and pre-operative transfusion rate in elderly patients with intertrochanteric fractures without increasing the risk of venous thrombosis.

Effectiveness of different doses and routes of administration of tranexamic acid for total hip replacement

PURPOSE

The aim of the study is to show the therapeutic efficacy, safety, and cost-benefit of using tranexamic acid (TXA), as well as the superiority of the route of administration and amount of dose in primary cementless total hip replacement (THR).

METHODS

In this prospective, randomized, double-blind study, we divided 200 patients into five groups of 40 patients each. The placebo group did not receive TXA. Three groups received 2 g TXA each (intravenous, topical, and combined intravenous + topical), while the fifth, combined + group, received 4 g TXA. Total blood loss was calculated, number of transfusions and thromboembolic vascular incidents were monitored, and a cost-benefit analysis of the use of TXA was performed.

RESULTS

Regardless of the route of administration, TXA statistically significantly reduced total blood loss (p = 0.000) and the need for transfusion (p = 0.000) compared with placebo. Total blood loss and the need for allogenic blood transfusion were statistically significantly reduced in the combined + group compared with placebo, and also compared with all other groups. Post-operative thromboembolic vascular incidents were not reported. The cost-benefit of using TXA in THR is associated with reduction of transfusion costs.

CONCLUSIONS

None of the TXA administration routes are superior to others, but multiple doses could statistically significantly reduce blood loss and transfusion requirements, which should be the subject of future researches.

[The influence of knee flexion position on postoperative blood loss and knee range of motion after total knee arthroplasty]

OBJECTIVE

To summarize research progress of the effect of knee flexion position on postoperative blood loss and knee range of motion (ROM) after total knee arthroplasty (TKA).

METHODS

The relevant literature at home and abroad was reviewed and summarized from mechanism, research status, progress, and clinical outcome. The differences of clinical results caused by different positions, flexion angles, and keeping time were compared.

RESULTS

Keeping knee flexion after TKA can reduce postoperative blood loss through the angle change of blood vessels and increase knee early ROM by improving flexion muscle strength. When the flexion angle of the knee is large and the flexion position is keeping for a long time, the postoperative blood loss and the knee ROM can be significantly improved. However, the amount of blood loss and ROM are not further improved in the patients with keeping knee flexion for more than 24 hours compared with less than 24 hours.

CONCLUSION

Keeping knee flexion after TKA is a simple and effective method to reduce postoperative blood loss and improve knee ROM. However, the optimal knee flexion angle and time are needed to be further explored.

High-dose (3 g) topical tranexamic acid has higher potency in reducing blood loss after total knee arthroplasty compared with low dose (500 mg): a double-blind randomized controlled trial

BACKGROUND

Topical intra-articular tranexamic acid (IA-TXA) has been proven to be safe and effective in reducing postoperative blood loss after primary total knee arthroplasty (TKA). The objective of this study was to investigate the efficacy of high dose (3 g) compared with low dose (500 mg) of IA-TXA in postoperative blood loss after primary TKA.

METHODS

A double-blind randomized controlled trial was conducted in 80 patients who had undergone primary TKA. The patients were divided into two groups according to intra-articular TXA doses: high-dose group (3 g IA-TXA) and low-dose group (500 mg IA-TXA). The drug was injected into the joint capsule after fascial closure without suction drainage. The primary outcomes were maximum hemoglobin drop (g/dL) and calculated total blood loss (mL). Postoperative blood transfusions, thromboembolic events and functional outcomes were also recorded.

RESULTS

The mean maximum hemoglobin drop was 1.3 g/dL lower in 3 g IA-TXA group compared to the 500 mg IA-TXA group [1.7 vs 3.0 g/dL, 95% confidence interval (CI) 0.9-1.7 g/dL, P < 0.001]. The 3 g IA-TXA group had 370 mL less calculated total blood loss compared to the 500 mg IA-TXA group (551 vs 921 mL, 95% CI 252-489 mL, P < 0.001). One patient in the 500 mg IA-TXA group required transfusion, while no patient in the 3 g IA-TXA group received transfusion (P = 0.31). Any thromboembolic event was not found, and functional outcome was similar between the two groups.

CONCLUSIONS

Application of high-dose, 3 g topical IA-TXA was 43% more effective in reducing postoperative blood loss compared with low dose of 500 mg in primary TKA. Optimal doses in between the above two doses may be a worthwhile further investigation.

An updated meta-analysis evaluating limb management after total knee arthroplasty-what is the optimal method?

Purpose

Postoperative knee flexion protocol has been widely recognized as a highly attractive, simple, and cost-effective tactic to improve patient’s outcomes after primary total knee arthroplasty (TKA). However, optimal knee position and duration of knee flexion are still controversial. The purpose of this meta-analysis was to compare the effectiveness of different postoperative knee flexion protocols, as an aid to find out optimal limb management strategy following TKA.

Methods

We conducted a meta-analysis to identify the available and relevant randomized controlled trials (RCTs) with regard to the influence of different postoperative knee positions on clinical outcomes after primary TKA in electronic databases, including PubMed, EMBASE, the Cochrane Library, Web of Science, CNKI, Wanfang Med Online, and VIP, up to May 2018. In this meta-analysis, three major subgroups based on diverse postoperative knee flexion protocols were considered: long-term (≥ 24 h) high flexion (> 30°), short term (< 24 h) high flexion (> 30°), and long-term (≥ 24 h) mild flexion (≤ 30°). The statistical analysis was performed using the Review Manager (RevMan) version 5.3 software.

Results

A total of 16 trials were finally included in this meta-analysis. The result of subgroup analysis indicated that keeping the knee in high flexion (> 30°) postoperatively for a long time (≥ 24 h) significantly reduced total blood loss (P < 0.00001), hidden blood loss (P < 0.00001), and transfusion requirements (P = 0.003) and led to a significant improvement in range of motion (ROM) at 1 week after operation (P < 0.00001); keeping the knee in high flexion (> 30°) postoperatively for a short time (< 24 h) significantly reduced total blood loss (P = 0.006) and hidden blood loss (P < 0.00001) but not significantly improved ROM at 1 week after operation (P = 0.34) and reduced transfusion requirements (P = 0.62); and keeping the knee in mild flexion (≤ 30°) postoperatively for a long time (≥ 24 h) significantly reduced total blood loss (P = 0.02) and transfusion requirements (P = 0.02) and improved ROM at 1 week after operation (P < 0.00001) but not significantly reduced hidden blood loss (P = 0.11). Furthermore, there was no significant difference with respect to the rates of wound-related infection and DVT between the three knee flexion subgroups.

Conclusions

This meta-analysis showed that the long-term (≥ 24 h) high flexion (> 30°) protocol could be an optimal limb management to reduce blood loss and blood transfusion requirements and facilitate early postoperative rehabilitation exercises in patients after primary TKA without increasing in complication rate.