How safe is blood, really?

Abdominal aortic calcification is an independent predictor of perioperative blood loss in posterior spinal fusion surgery

OBJECTIVE

Abdominal aortic calcification (AAC), often found incidentally on lateral lumbar radiographs, is increasingly recognized for its association with adverse outcomes in spine surgery. As a marker of advanced atherosclerosis affecting cardiovascular dynamics, this study evaluates AAC's impact on perioperative blood loss in posterior spinal fusion (PSF).

METHODS

Patients undergoing PSF from March 2016 to July 2023 were included. Estimated blood loss (EBL) and total blood volume (TBV) were calculated. AAC was assessed on lateral lumbar radiographs according to the Kauppila classification. Predictors of the EBL-to-TBV ratio (%EBL/TBV) were examined via univariable and multivariable regression analyses, which adjusted for parameters such as hypertension and aspirin use.

RESULTS

A total of 199 patients (47.2% female) were analyzed. AAC was present in 106 patients (53.3%). AAC independently predicted %EBL/TBV, accounting for an increase in blood loss of 4.46% of TBV (95% CI 1.17-7.74, p = 0.008).

CONCLUSIONS

This is the first study to identify AAC as an independent predictor of perioperative blood loss in PSF. In addition to its link to degenerative spinal conditions and adverse postoperative outcomes, the relationship between AAC and increased blood loss warrants attention in patients undergoing PSF.

Does the accelerometer-based navigation system reduce blood loss and transfusion in one-stage sequential bilateral total knee arthroplasty? A randomized double-blind controlled trial

BACKGROUND

Total knee arthroplasty (TKA) is associated with significant blood loss and postoperative transfusion. The accelerometer-based navigation (ABN) system guides the bone cutting plane without breaching the intramedullary canal, which may reduce bleeding. This study aimed to investigate blood loss and transfusion compared between the ABN system and the conventional procedure in patients undergoing one-stage sequential bilateral TKA (SBTKA).

METHODS

A total of 66 patients scheduled for SBTKA were randomly allocated to either the ABN or conventional group. Postoperative hematocrit (Hct) level, drainage blood loss, transfusion rate, and amount of packed red cell transfusion were collected. Total red blood cell (RBC) loss was then calculated for the primary outcome.

RESULTS

The mean calculated total RBC loss in the ABN and conventional group was 669.7 and 630.0 mL, respectively (p = 0.572). There was no significant difference between groups for other evaluated outcome parameters, including postoperative Hct level, drainage blood loss, or packed red cell transfusion volume. All patients in the conventional group required postoperative blood transfusion while 96.8% of patients in the ABN group were transfused.

CONCLUSIONS

The total RBC loss and volume of packed red cells transfusion were not significant difference between interventions, which suggest no benefit of the ABN system in reducing blood loss and transfusion in patients undergoing SBTKA.

TRIAL REGISTRATION

The protocol of this study was registered in the Thai Clinical Trials Registry database no. TCTR20201126002 on 26/11/2020.

Transfusion after harvesting bone graft with RIA: Practice changes reduced transfusion rate by more than half

INTRODUCTION

The Reamer Irrigator Aspirator (RIA) is frequently used as a tool for bone graft harvesting procedures. The initial use of this instrument for bone grafting was met with significant blood loss and high transfusion rates. However, the RIA remains an excellent tool to obtain large volumes of viable autologous graft. The aim of this study was to investigate how changes in the technical use of the RIA may affect blood loss.

MATERIALS AND METHODS

We conducted a retrospective chart review of all patients who underwent RIA bone graft harvest over a 12-year study period. The patients were divided into two cohorts based upon changes in the technique used to obtain autograft harvest with the RIA. The traditional cohort (2008-2012) connected the RIA to dilation and curettage suction and selected reamer size based on radiographic parameters. The modified cohort (2012-2020) connected the RIA to wall suction, used improved techniques for reamer head sizing, and more diligence was paid toward the time the RIA was suctioning in the canal. Demographic information, surgical details, pre- and post-operative hematocrit (HCT), transfusion rate, intra-operative blood loss, reported volume of graft harvested, and iatrogenic fracture were recorded.

RESULTS

201 patients were included in the study with 61 patients in the traditional and 140 patients in the modified cohorts respectively. The average age was 51 years (range: 18-97) with 107 (53%) males. There was no difference in the demographic data between the two cohorts. No difference was noted between the traditional and modified cohorts in terms of the amount of average graft harvested (54cc vs 51cc; p = 0.34) or major complications (1 vs 2; p = 0.91). However, when comparing the traditional versus modified cohorts the traditional group demonstrated a larger average blood loss (675cc vs 500cc; p=<0.01) and HCT drop (13.7 vs 9.5; p=<0.01) with a higher transfusion rate (44% vs 19%; p = 0.001).

CONCLUSION

This series demonstrated a significant improvement in blood loss and transfusion with modified techniques used to obtain autologous bone graft with the RIA. Importantly, these techniques do not appear to limit bone graft harvest yield and can therefore be efficiently implemented without limiting the utility of the RIA.

Hidden blood loss in direct anterior total hip arthroplasty: a prospective, double blind, randomized controlled trial on topical versus intravenous tranexamic acid

BACKGROUND

Despite a plethora of literature reporting on the use of tranexamic acid (TXA) in total hip arthroplasty (THA), little is available on its effect on post-operative hidden blood loss and even less on its use in the direct anterior approach (DAA), which is gaining popularity.

MATERIALS AND METHODS

This study was designed as a prospective, double blind, single centre, randomized controlled trial. Sixty patients were allocated to intravenous administration of 1.5 g of TXA just before wound closure while 60 patients were allocated to topical application of 3.0 g of TXA via a subfascial drain at the end of the procedure. Post-operative blood loss was (1) calculated via a well-established formula based on pre- and post-operative Hb levels, patients characteristics and intra-operative blood loss and (2) measured via the amount that collected in the subfascial drain over time.

RESULTS

No statistical significant difference in post-operative blood loss was found, neither when the formula was used (0.55 L [topical] vs 0.67 L [IV]; p = .140) nor when looking at the drain output (0.25 L [topical] vs 0.29 L [IV]; p = .108). No significant difference in secondary outcome measures, such as transfusion of units of packed red blood cells, length of hospital stay or the occurrence of venous thromboembolisms, could be found either.

CONCLUSIONS

This study provides detailed insights into the intra- and post-operative blood loss in DAA THA and shows that topical and IV TXA have similar effects on hidden blood loss. Clinical Trial Number: NCT01940692.

LEVEL OF EVIDENCE I

Level I-Randomized Controlled Trial.

Predictive Factors for Blood Transfusion after Total Knee Arthroplasty

Objectives  The present paper aims to (1) verify the incidence and volume of blood transfusion among patients undergoing unilateral cemented total knee arthroplasty (TKA) in a single Brazilian reference center; (2) identify pre and perioperative variables to determine subjects with higher risk (i.e., predictive factors) for blood transfusion within 48 hours following surgery; (3) estimate the risk of blood transfusion during the first 48 hours after the procedure.

Methods  The initial sample consisted of all patients undergoing TKA from August 2010 to August 2013. After applying the exclusion criteria, 234 patients aged 30 to 83 years old and diagnosed with primary or secondary osteoarthritis due to rheumatoid arthritis remained in the study.

Results  Preoperative hemoglobin levels ≤ 12.3 g/dL and ischemia time ≥ 87 minutes were independent predictors for post-TKA blood transfusion, with a relative risk of 2.48 and 1.78, respectively. Approximately half of the TKA patients (51.3%) presenting these two variables required a blood transfusion.

Conclusion  The incidence of post-TKA blood transfusion was 33.7%. On average, each transfused patient received 480 mL of packed red blood cells. Preoperative hemoglobin levels ≤ 12.3 g/dL ( p  < 0.001) and ischemia time ≥ 87 minutes ( p  < 0.047) were independent predictors for blood transfusion in TKA using a pneumatic cuff, with a relative risk of 2.48 and 1.78, respectively. Age, gender, diagnosis, or body mass index were not considered independent predictors for the need for blood transfusion up to 48 hours after the procedure.

Perioperative management of elderly patients with osteoarthritis requiring total knee arthroplasty

Knee osteoarthritis is a common arthritic disease which mainly affects the elderly (≥65 years old) population. As a result of the cartilage degeneration, it can cause a significant amount of pain and functional limitation. In patients who are refractory to conservative management, total knee arthroplasty is being utilised as the last resort in management. In this review, we discuss the perioperative management of elderly patients with osteoarthritis requiring total knee arthroplasty.

Function of Hemoglobin-Based Oxygen Carriers: Determination of Methemoglobin Content by Spectral Extinction Measurements

Suspensions of hemoglobin microparticles (HbMPs) are promising tools as oxygen therapeutics. For the approval of clinical studies extensive characterization of these HbMPs with a size of about 750 nm is required regarding physical properties, function, pharmaco-kinetics and toxicology. The standard absorbance measurements in blood gas analyzers require dissolution of red blood cells which does not work for HbMP. Therefore, we have developed a robust and rapid optical method for the quality and functionality control of HbMPs. It allows simultaneous determination of the portion of the two states of hemoglobin oxygenated hemoglobin (oxyHb) and deoxygenated hemoglobin (deoxyHb) as well as the content of methemoglobin (metHb). Based on the measurement of collimated transmission spectra between 300 nm and 800 nm, the average extinction cross section of HbMPs is derived. A numerical method is applied to determine the composition of the HbMPs based on their wavelength-dependent refractive index (RI), which is a superposition of the three different states of Hb. Thus, light-scattering properties, including extinction cross sections can be simulated for different compositions and sizes. By comparison to measured spectra, the relative concentrations of oxyHb, deoxyHb, metHb are accessible. For validation of the optically determined composition of the HbMPs, we used X-ray fluorescence spectrometry for the ratio of Fe(II) (oxyHb/deoxyHb) and Fe(III) (metHb). High accuracy density measurements served to access heme-free proteins, size was determined by dynamic light scattering and analytical centrifugation and the shape of the HbMPs was visualized by electron and atomic force microscopy.

Intravenous Combined with Topical Tranexamic Acid Administration Has No Additional Benefits Compared with Intravenous Administration Alone in High Tibial Osteotomy: A Retrospective Case-Control Study

Objective

To investigate whether intravenous combined with topical administration of tranexamic acid (TXA) is superior to intravenous administration alone in terms of blood loss, incision complications, functional recovery, and pain relief in high tibial osteotomy (HTO).

Methods

Clinical data of patients with knee osteoarthritis (OA) treated with unilateral HTO were retrospectively reviewed. The patients were grouped according to the TXA administration method, with 24 patients in the combined group and 21 in the solo group. In the combined group, 100 mL saline containing 1 g TXA was intravenously administered before application of a tourniquet, and 20 mL saline containing 2 g TXA was injected through a drainage tube after closure of the incision. Alternatively, 100 mL of saline containing 1 g TXA was intravenously administered before application of a tourniquet in the solo group. The blood loss and adverse events were compared between the two groups.

Results

All patients were followed for more than half a year. The drainage volume on the first day and total blood loss on the second day after surgery in the combined and single treatment groups were 130.06 ± 29.22 and 165.35 ± 43.08 mL (P < 0.05), respectively, and 327.17 ± 64.26 and 385.45 ± 63.31 mL (P < 0.05). There were no blood transfusions in either group. One case of delayed incision healing was observed in the solo group, and no such event occurred in the combined group. There were no significant differences between the two groups in terms of the following factors: the activated partial thromboplastin time (APTT) and prothrombin time (PT); levels of fibrinogen (FIB) and D‐dimer on the second day after surgery; numbers of hospitalization days and thromboembolism events; and knee joint function and visual analog score 6 months after surgery.

Conclusion

Intravenous combined with topical TXA administration in HTO is superior to intravenous administration alone for reducing postoperative blood loss and drainage volume without thromboembolic complications. However, even with only intravenous TXA administration, no cases of blood transfusion and only 1 case of incision complication occurred. At the same time, the combined use of TXA did not improve the recovery of knee joint function and pain relief after HTO.

Utilisation of emergency blood in a cohort of South African emergency centres with no direct access to a blood bank

Introduction

The transfusion of emergency blood is an essential part of haemostatic resuscitation. Locally, where direct access to a blood bank is limited, emergency blood is stored within emergency centres. It was previously suggested that stored blood provides inadequate volumes compared to what is needed. Minimal data are available regarding indications for emergency blood usage. We aimed to describe the utilisation of emergency blood in selected Cape Town emergency centres.

Materials and methods

A cross-sectional study was carried out at three secondary level emergency centres (no blood bank), and one tertiary centre (with a blood bank). Data from emergency blood recipients were recorded over a three-month study period. Indications for transfusion, number of units and location of transfusion were recorded. Indications and usage location were described in numbers and proportions.

Results

A total of 329 emergency blood units were transfused to 210 patients. Trauma accounted for 39% (n = 81) of cases and other surgical conditions for 22% (n = 47), particularly upper gastrointestinal 11% (n = 24) and perioperative bleeding 8% (n = 16). Medical conditions accounted for 15% (n = 31), with anaemia 13% (n = 27), the most prevalent indication. Gynaecological conditions accounted for 15% (n = 32), mostly ectopic pregnancy 8% (n = 17). The majority of emergency blood, 77% (n = 253) were used in the emergency centres or operating theatres, 6% (n = 21).

Conclusion

Trauma remains a major indication for emergency blood transfusion in this setting. This study questions the use of emergency blood for certain non-urgent diagnoses (i.e. anaemia). Given the scarcity of this resource and limitations to access, appropriate use of emergency blood needs to be better defined locally. Ongoing monitoring of the indications for which emergency blood is used, improved transfusion stewardship and better systems to access emergency blood should be a priority in this setting.

Blood loss of total knee arthroplasty in osteoarthritis: an analysis of influential factors

BACKGROUND

Total knee arthroplasty is regarded as the most effective treatment for severe knee osteoarthritis. The influential factors of blood loss in total knee arthroplasty remain controversial. The study aims to explore the influential factors of blood loss in total knee arthroplasty comprehensively.

MATERIAL AND METHODS

Three hundred and four osteoarthritis patients undergoing unilateral primary total knee arthroplasty were enrolled. Demographic characteristics, laboratory results, surgical protocol, and hemostatic and anticoagulation drugs were collected. Estimation of blood loss was calculated using the Gross equation. Multivariable stepwise linear regression analysis was performed to find out the influential factors.

RESULTS

Total blood loss reached the biggest volume (1346 ± 671 mL) in the post-operative third day. Hidden blood loss reached 465 ± 358 mL. Gender, tranexamic acid, prosthesis type, and drainage were proven to be positively correlated with the total blood loss (all P < 0.05). Male appeared to suffer more surgical blood loss than female. Posterior cruciate stabilizing prosthesis might lead to more surgical blood loss than posterior cruciate retaining prosthesis. Tranexamic acid could effectively reduce total blood loss while drainage might increase bleeding. Gender and anticoagulation drugs were correlated with hidden blood loss (both P < 0.05). Low molecular weight heparin resulted in less hidden blood loss than rivaroxaban.

CONCLUSIONS

Posterior cruciate retaining prosthesis and topical use of tranexamic acid were preferred to reduce total blood loss. Drainage was not recommended due to the risk of increasing bleeding. Low molecular weight heparin was recommended to prevent venous thrombosis.

Tranexamic acid is effective for blood management in open-wedge high tibial osteotomy

INTRODUCTION

There has been paucity in literature regarding the blood-sparing effect of TXA after high tibial osteotomy (HTO). The purpose of this study is to determine the efficacy of tranexamic acid (TXA) with regard to its blood-sparing effects in open-wedge HTO, and to assess thromboembolic complications in patients undergoing open-wedge HTO with or without the use of TXA.

HYPOTHESIS

The intravenous TXA would reduce postoperative blood loss and transfusion requirements without increasing thromboembolic complications in open-wedge HTO.

MATERIALS AND METHODS

From March 2011 to December 2016, medial open-wedge HTO was performed in 150 consecutive knees with varus gonarthrosis. The mean age at the time of surgery was 55.3±5.0 years. TXA was intravenously used in the latter 75 knees (TXA group), and the group was retrospectively compared with the former 75 knees without use of TXA (control group). Outcome measures were postoperative hemoglobin drop, drain amount, total estimated blood loss, transfusion requirements, and incidence of thromboembolic complications.

RESULTS

The use of TXA led to a significant decrease in hemoglobin drop (p<0.001) and drain amount (p=0.025). Total estimated blood loss was lower in the TXA group than in the control group (p<0.001). Two knees in the control group had postoperative blood transfusion, compared to none in the TXA group (p>0.05). There were no thromboembolic complications such as symptomatic deep vein thrombosis and pulmonary embolism in both groups.

CONCLUSION

The use of TXA reduced perioperative hemoglobin drop, drain amount, and total estimated blood loss without thromboembolic complications in patients undergoing open-wedge HTO. Therefore, the use of TXA is a safe and viable option for perioperative blood management in open-wedge HTO.

LEVEL OF EVIDENCE

III, Case control study.

Knowledge of bloodless medicine among nurses at the Medical/Surgical Directorate of Komfo Anokye Teaching Hospital, Ghana; a descriptive cross sectional study

OBJECTIVE

This study assessed the knowledge of bloodless medicine (BM) among nurses at the medical and surgical directorate of Komfo Anokye Teaching Hospital. A paper questionnaire was administered to 322 nurses to obtain information on socio-demographic characteristics and knowledge of BM.

RESULTS

More than half (52.1%) of the nurses were aware of BM. The major source of information on BM was from the internet. Out of the study population, 90.1% knew iron therapy as BM strategy. The largest proportions of the participants (51.2%) had witnessed BM treatment at the medical and surgical directorate with the Tot'hema (44.6%) being the major used drug. Flu-like symptoms (37.0%) and organ damage (50.0%) were the commonly known side effects of BM respectively. Most of the participants (97.5%) knew that doctors request for blood transfusion. The major known reason for demand of BM was religious beliefs (53.7%). Higher percentages (71.9%) of the participants were not aware of bloodless surgery although the few who were aware, had heard of this through an internet search. Participants were generally aware of BM but less knowledgeable of specific components of BM. There is the need for prompt hospital and public health education through workshops and in-service training.

HESTAT: Study protocol for a phase II/III, randomized, placebo-controlled, single blind study to evaluate the new hemostatic agent TT-173 in total knee arthroplasty

BACKGROUND

Several hemostatic treatments intended to reduce the bleeding associated to total knee arthroplasty have been investigated with varying degrees of success. TT-173 is a new topical agent based on recombinant tissue factor that activates the extrinsic pathway of coagulation. This trial aim is to evaluate the efficacy and safety of TT-173 in total knee arthroplasty.

METHODS/DESIGN

This is a phase II/III, sequential, simple blind, randomized, multicenter, placebo controlled and parallel clinical trial that will recruit 189 evaluable patients. Those randomized to treatment group will receive 2mg of TT-173 over the surgical surfaces of the knee. Control patients will receive physiologic saline. The follow up will consist in 6 visits during a period of 35 (±7) days. Primary endpoints will be the total blood loss and the incidence and severity of adverse events. Secondary and exploratory endpoints will include drainage production, decrease in hemoglobin level, transfusion ratio, analytical alterations, pain intensity, motion range, immunogenicity of TT-173 and the occurrence of systemic absorption. At the end of phase II, results will be evaluated by an independent committee that will recommend the continuation or the discontinuation of the trial.

DISCUSSION

The design proposed maximizes the safety of the participants, avoids the risk of bias derived from the limitations of masking and enable the eventual discontinuation of the trial if this is recommended by the Interim Analysis Committee. If TT-173 proves its efficacy and safety in this indication, it would become a useful tool to improve the bleeding control in total knee arthroplasty.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02687399. Registered the 9th of February 2016.

Is This Autograft Worth It?: The Blood Loss and Transfusion Rates Associated With Reamer Irrigator Aspirator Bone Graft Harvest

OBJECTIVES

To investigate the blood loss and transfusion rate associated with the use of reamer irrigator aspirator (RIA).

DESIGN

Retrospective review.

SETTING

Academic Level-I trauma hospital.

PATIENTS

One hundred eight patients requiring bone graft harvest for surgical reconstruction of nonunion or failed arthrodesis.

INTERVENTION

Bone graft harvest preformed via RIA or iliac crest bone graft (ICBG).

MAIN OUTCOME MEASURE

Blood loss as measured by a change in preoperative and postoperative hematocrit (Hct). In addition, postoperative transfusion reported intraoperative blood loss, volume of graft harvested, and major complications.

RESULTS

The average Hct drop was found to be 13.7 (4.1-27.4) in the RIA cohort of 61 patients and 7.36 (1.2-14.5) in the ICBG cohort of 47 patients (P = 0.013). Operative reports documented an average estimated blood loss of 674 mL (100-2000 mL) in the RIA cohort compared with 255 mL (50-1000 mL) in the ICBG cohort (P < 0.001). Twenty-seven patients (44%) required blood transfusion after RIA, whereas 10 patients (21%) required blood transfusion after ICBG (odds ratio 5.32, 95% confidence interval 2.2-6.3, P < 0.001). RIA procedures collected an average 53 mL (20-100 mL) of bone graft compared with 27 mL (15-50 mL) with ICBG. There was no significant difference between groups regarding age, sex, medical comorbidities, or postoperative major complications.

CONCLUSIONS

This series demonstrated that 44% of patients undergoing RIA bone graft harvest required transfusion, with a mean Hct drop of 13.7 across all subjects, which is significantly greater than that associated with ICBG.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Association of an In-House Blood Bank with Therapy and Outcome in Severely Injured Patients: An Analysis of 18,573 Patients from the TraumaRegister DGU®

Introduction

Hemorrhagic shock remains one of the most common causes of death in severely injured patients. It is unknown to what extent the presence of a blood bank in a trauma center influences therapy and outcome in such patients.

Material and Methods

We retrospectively analyzed prospectively recorded data from the TraumaRegister DGU® and the TraumaNetzwerk DGU®. Inclusion criteria were Injury Severity Score (ISS) ≥ 16, primarily treated patients, and hospital admission 2 years before or after the audit process.

Results

Complete data sets of 18,573 patients were analyzed. Of 457 hospitals included, 33.3% had an in-house blood bank. In trauma centers with a blood bank (HospBB), packed red blood cells (PRBCs) (21.0% vs. 17.4%, p < 0.001) and fresh frozen plasma (FFP) (13.9% vs. 10.2%, p <0.001) were transfused significantly more often than in hospitals without a blood bank (Hosp0). However, no significant difference was found for in-hospital mortality (standard mortality ratio [SMR, 0.907 vs. 0.945; p = 0.25). In patients with clinically apparent shock on admission, no difference of performed transfusions were present between HospBB and Hosp0 (PRBCs, 51.4% vs. 50.4%, p = 0.67; FFP, 32.7% vs. 32.7%, p = 0.99), and no difference in in-hospital mortality was observed (SMR, 0.907 vs. 1.004; p = 0.21).

Discussion

In HospBB transfusions were performed more frequently in severely injured patients without positively affecting the 24h mortality or in-house mortality. Easy access may explain a more liberal transfusion concept.

Intravenous vs Topical Tranexamic Acid in Total Knee Arthroplasty Without Tourniquet Application: A Randomized Controlled Study

BACKGROUND

Use of tranexamic acid (TXA) is effective and safe in reducing the blood loss in total knee arthroplasty (TKR) performed using a tourniquet, but, data in TKR performed without tourniquet are limited, and there is no study comparing the topical (T) with intravenous (IV) TXA administration. Our aim was to compare the topical (T) with intravenous (IV) TXA administration in TKR performed without tourniquet.

MATERIAL AND METHODS

A total of 120 patients undergoing unilateral TKR for knee osteoarthritis were included in a prospective randomized study. Operations were performed under spinal anesthesia, no tourniquet was used, and the postoperative regime was the same for all patients. Patients were divided into 3 groups; in group C (control), 40 patients received no TXA, in group IV, 40 patients received 1 g of TXA intravenously, and in group L, 1 g of TXA was applied locally to 40 patients. The primary outcome measures included the calculated blood loss, the transfusion rate, and quantity of allogeneic blood units, whereas secondary outcome measures were complications.

RESULTS

There was no statistically significant difference in patient's demographics and perioperative results. Calculated blood loss, allogeneic blood transfusion rate, and quantity in group C were significantly higher compared with those of TXA groups (P < .001). There was no significant difference in complications rate between the 3 groups.

CONCLUSIONS

According to the results of this study, IV or T administration of 1-g TXA significantly reduced the blood loss and the need for allogeneic blood transfusion in patients undergoing TKR without a tourniquet (with no significant difference between the 2 routes of administration).

Benefits of Limited Use of a Tourniquet Combined With Intravenous Tranexamic Acid During Total Knee Arthroplasty

BACKGROUND

Blood loss during total knee arthroplasty (TKA) may require blood transfusions that are associated with increased risk, morbidity, and cost. Multiple techniques exist to reduce blood loss in TKA, including the use of a tourniquet and tranexamic acid (TXA). While multiple studies suggest that TXA is effective in reducing blood loss, the use of a tourniquet is more controversial. We studied the combined effect of TXA with a limited-use tourniquet on blood loss and complications in the setting of primary TKA.

METHODS

A retrospective review of a prospectively gathered arthroplasty database from a single institution was performed. We compared our limited-use cohort data with the published results of randomized controlled trials evaluating the effectiveness of tourniquets used during the entire TKA procedure.

RESULTS

Fifty-one procedures from our institution's database met the inclusion criteria. TXA (administered in a single 15-mg/kg dose) with limited tourniquet use (a mean duration of 26.3 minutes) resulted in an average intraoperative estimated blood loss of 94.7 mL. The mean decrease in hemoglobin from the preprocedure baseline to postoperative day 1 was 2.6 ± 0.9 g/dL (P<0.001), and only 2 of the 51 procedures required a blood transfusion. When compared to recent randomized controlled trials, the 51 procedures demonstrated lower levels of blood loss, similar operative time, and no increase in morbidity or mortality.

CONCLUSION

Our study results suggest that using TXA in combination with a tourniquet during the cementation portion only of a TKA provides a reasonable operative time and low intraoperative blood loss without increasing perioperative morbidity or complications.

Predicting Blood Loss in Total Knee and Hip Arthroplasty

Marked blood loss during lower extremity total joint arthroplasties may lead to higher rates of transfusion, which may negatively affect surgical outcomes and yield greater complication rates. It is therefore ideal to identify factors that may increase the likelihood of blood loss, so they can be modified. From this review, it can be concluded that preoperative anemia, older age, multiple comorbidities, increased operative time, and use of postoperative anticoagulation may lead to higher blood loss and transfusion rates, although the influence of other factors remains controversial.

Perioperative solutions for rapid recovery joint arthroplasty: get ahead and stay ahead

Rapid recovery after total joint arthroplasty requires patients to get ahead and stay ahead or the four impediments to early rehabilitation and discharge: volume depletion, blood loss, pain, and nausea. Adequate volume resuscitation starts before entering the operating room and focuses on intravenous fluids rather than red blood cell transfusion. Tranexamic acid limits blood loss and reduces the need for most other blood management systems. Rapid recovery pain management focuses on minimizing parenteral opioids. A short-acting spinal with a peri-articular local anesthetic injection is reliable, reproducible, and safe. Patients at risk for post-operative nausea are treated with anti-emetic medications and perioperative dexamethasone. These interventions reflect a transition from the sick-patient model to the well-patient model and make rapid recovery joint arthroplasty a reality in 2015.

Clinical experience with tranexamic acid during primary total hip arthroplasty

We examined whether a single 1-gram preoperative dose of tranexamic acid (TXA) was effective in reducing 1) allogeneic blood transfusion, 2) haemoglobin (Hb) decreases, and 3) perioperative blood loss following primary total hip arthroplasty (THA) and resurfacing hip arthroplasty (RHA). One hundred and thirty-two patients (88 THA, 44 RHA; 66M, 66F; mean age = 58.2 years) who received TXA were compared with a control group matched for starting Hb, body mass index (BMI), age and gender. For the THR, transfusion rates were 4.5% and 19.3% for the TXA and control groups, respectively (p = 0.001) with no difference for the resurfacing patients. The mean overall Hb decrease was significantly lower in the TXA treatment groups for both THA and RHA patients (p<0.0001 and p = 0.01 respectively). 1 g of tranexamic acid administered preoperatively significantly reduced the mean decrease in haemoglobin as well as risk of transfusion.

Artificial oxygen carrier with pharmacologic actions of adenosine-5'-triphosphate, adenosine, and reduced glutathione formulated to treat an array of medical conditions

Effective artificial oxygen carriers may offer a solution to tackling current transfusion medicine challenges such as blood shortages, red blood cell storage lesions, and transmission of emerging pathogens. These products, could provide additional therapeutic benefits besides oxygen delivery for an array of medical conditions. To meet these needs, we developed a hemoglobin (Hb)-based oxygen carrier, HemoTech, which utilizes the concept of pharmacologic cross-linking. It consists of purified bovine Hb cross-linked intramolecularly with open ring adenosine-5'-triphosphate (ATP) and intermolecularly with open ring adenosine, and conjugated with reduced glutathione (GSH). In this composition, ATP prevents Hb dimerization, and adenosine promotes formation of Hb polymers as well as counteracts the vasoconstrictive and pro-inflammatory properties of Hb via stimulation of adenosine receptors. ATP also serves as a regulator of vascular tone through activation of purinergic receptors. GSH blocks Hb's extravasation and glomerular filtration by lowering the isoelectric point, as well as shields heme from nitric oxide and reactive oxygen species. HemoTech and its manufacturing technology have been broadly tested, including viral and prion clearance validation studies and various nonclinical pharmacology, toxicology, genotoxicity, and efficacy tests. The clinical proof-of-concept was carried out in sickle cell anemia subjects. The preclinical and clinical studies indicate that HemoTech works as a physiologic oxygen carrier and has efficacy in treating: (i) acute blood loss anemia by providing a temporary oxygen bridge while stimulating an endogenous erythropoietic response; (ii) sickle cell disease by counteracting vaso-occlusive/inflammatory episodes and anemia; and (iii) ischemic vascular diseases particularly thrombotic and restenotic events. The pharmacologic cross-linking of Hb with ATP, adenosine, and GSH showed usefulness in designing an artificial oxygen carrier for multiple therapeutic indications.

Blood management strategies for total knee arthroplasty

Perioperative blood loss during total knee arthroplasty can be significant, with magnitudes typically ranging from 300 mL to 1 L, with occasional reports of up to 2 L. The resultant anemia can lead to severe complications, such as higher rates of postoperative infection, slower physical recovery, increased length of hospital stay, and increased morbidity and mortality. Although blood transfusions are now screened to a greater extent than in the past, they still carry the inherent risks of clerical error, infection, and immunologic reactions, all of which drive the need to develop alternative blood management strategies. Thorough patient evaluation is essential to individualize care through dedicated blood management and conservation pathways in order to maximize efficacy and avoid associated complications. Interventions may be implemented preoperatively, intraoperatively, and postoperatively.

Measures of stored red blood cell quality

Blood banking underpins modern medical care, but blood storage, necessary for testing and inventory management, reduces the safety and efficacy of individual units of red blood cells (RBCs). Stored RBCs are damaged by the accumulation of their own waste products, by enzymatic and oxidative injury, and by metabolically programmed cell death. These chemical activities lead to a complex RBC storage lesion that includes haemolysis, reduced in vivo recovery, energy and membrane loss, altered oxygen release, reduced adenosine tri-phosphate and nitric oxide secretion, and shedding of toxic products. These toxic products include lysophospholipids that can cause transfusion-related acute lung injury, free iron that can potentiate infections and cause inflammation, and shed microvesicles that can scavenge nitric oxide and potentiate inflammation and thrombosis. However, most of the obvious negative outcomes of RBC storage are uncommon and appear to be related to exceptionally bad units. Generally, the quality of stored RBCs is highly related to the conditions of storage, so refrigerator temperature, intact bags, residual leucocyte counts and visible haemolysis remain excellent general measures. Specific biochemical measures, such as adenosine 5'-triphosphate (ATP) and 2,3-diphosphoglycerate (DPG) concentrations, calcium and potassium content or lipid breakdown products, require specialized measures that are not widely available, involve destructive testing and generally reflect only a part of the storage lesion. This review describes a number of components of the storage lesion and their measurement and attempts to access the utility of the measures.

Red blood cell alloimmunization in sickle cell disease: prevalence in 2010

BACKGROUND

Transfusion of red blood cells (RBCs) is frequently required for care of individuals with sickle cell disease (SCD). Alloimmunization rates are high and may be reduced by matching for RBC antigens that can cause alloimmunization.

STUDY DESIGN AND METHODS

During the PROACTIVE Feasibility Study, patients with SCD age 2 years or older admitted for pain without acute chest syndrome were enrolled for possible randomization to preventive blood transfusion or standard care. Transfusion and antibody histories were obtained at each site, and antibody screening was done, to assess transfusion burden and alloimmunization prevalence. Participating sites were surveyed regarding antigen matching practice.

RESULTS

A total of 237 patients (169 SS, 42 SC, 15 Sβ(0) -thalassemia, 11 Sβ(+) -thalassemia), 118 males and 119 females, were enrolled. Mean age was 19.3 years (range, 2.0-68.0); there were 122 children and 115 adults. A total of 75.8% had received at least a single transfusion of RBCs before the study. Thirty-four patients (14.4%) had a history of at least one alloantibody and 17 of these had more than one. When surveyed, 19 sites (83% of responders) reported antigen matching to at least include C, E, and K for transfusion of all patients with SCD.

CONCLUSION

Though antigen typing before transfusion of people with SCD and providing antigen-negative units is now widely employed by sickle cell centers, the alloimmunization rate remains quite high in contemporary sickle cell populations and may be due in large part to transfusions received at institutions not providing extended matching.

The management of blood safety in the presence of uncertain risk: a United kingdom perspective

Millions of patients in the UK benefit from the use of both plasma derivatives and blood components that are seen as critical interventions in current medicine. Measures are in place to significantly reduce the risks associated with blood transfusion and plasma derivatives; however, these measures themselves are not risk free. Over the past 20 years, advances in technology and regulation have seen major reductions in the risks associated with transfusion. International blood services, industry, and regulators strive to maintain safety levels through constant monitoring, assessment, and response to changing risk factors. Regulation of screening tests together with the development and introduction of nucleic acid technique tests for hepatitis B virus, hepatitis C virus, and human immunodeficiency virus has improved blood safety. However, other risks, including the changing epidemiology of transfusion-transmitted infections, bacterial contamination of platelets, incorrect blood component transfusion, and variant Creutzfeldt-Jakob disease, require further attention. Risks such as these are often complex, and there is a difficult balance to be struck between donors/recipients' benefit and adequacy of blood supply. The introduction of any new safety measure therefore requires robust, evidence-based evaluation of associated benefit, both clinical and economical. This review presents a UK perspective on how the safety of the blood supply is maintained in the face of uncertain risks.

Oncologic outcomes following radical prostatectomy with intraoperative cell salvage

PURPOSE

To evaluate oncologic outcomes following the use of intraoperative cell salvage (IOCS) as a blood loss management strategy during open radical prostatectomy (RP).

METHODS

We retrospectively reviewed all open retropubic RP cases performed by a single surgeon. Patients were identified who received IOCS blood and evaluated for an increased risk of biochemical recurrence (BCR) and overall mortality.

RESULTS

The study cohort consisted of 1,862 men, 395 (21.2%) of whom received IOCS blood. At a median follow-up of 47.0 months, men who received IOCS blood were not at an increased risk of BCR (P = 0.323) or all-cause mortality (P = 0.892). IOCS use did not confer an increased risk of BCR within any D'Amico preoperative risk category (low risk, P = 0.592; intermediate risk, P = 0.107; and high risk, P = 0.697).

CONCLUSIONS

IOCS is safe for the management of blood loss during RP. At long-term follow-up, IOCS use was not associated with an increased risk of BCR or death. While it remains preferable to avoid any form of blood transfusion, we advocate for the use of IOCS in place of allogeneic blood. These conclusions are drawn from our study of the largest and longest followed cohort patients who received IOCS blood during RP.

Synthesis, biophysical properties, and oxygenation potential of variable molecular weight glutaraldehyde-polymerized bovine hemoglobins with low and high oxygen affinity

In a recent study, ultrahigh molecular weight (Mw ) glutaraldehyde-polymerized bovine hemoglobins (PolybHbs) were synthesized with low O2 affinity and exhibited no vasoactivity and a slight degree of hypertension in a 10% top-load model.(1) In this work, we systematically investigated the effect of varying the glutaraldehyde to hemoglobin (G:Hb) molar ratio on the biophysical properties of PolybHb polymerized in either the low or high O2 affinity state. Our results showed that the Mw of the resulting PolybHbs increased with increasing G:Hb molar ratio. For low O2 affinity PolybHbs, increasing the G:Hb molar ratio reduced the O2 affinity and CO association rate constants in comparison to bovine hemoglobin (bHb). In contrast for high O2 affinity PolybHbs, increasing the G:Hb molar ratio led to increased O2 affinity and significantly increased the CO association rate constants compared to unmodified bHb and low O2 affinity PolybHbs. The methemoglobin level and NO dioxygenation rate constants were insensitive to the G:Hb molar ratio. However, all PolybHbs displayed higher viscosities compared to unmodified bHb and whole blood, which also increased with increasing G:Hb molar ratio. In contrast, the colloid osmotic pressure of PolybHbs decreased with increasing G:Hb molar ratio. To preliminarily evaluate the ability of low and high O2 affinity PolybHbs to potentially oxygenate tissues in vivo, an O2 transport model was used to simulate O2 transport in a hepatic hollow fiber (HF) bioreactor. It was observed that low O2 affinity PolybHbs oxygenated the bioreactor better than high O2 affinity PolybHbs. This result points to the suitability of low O2 affinity PolybHbs for use in tissue engineering and transfusion medicine. Taken together, our results show the quantitative effect of varying the oxygen saturation of bHb and G:Hb molar ratio on the biophysical properties of PolybHbs and their ability to oxygenate a hepatic HF bioreactor. We suggest that the information gained from this study can be used to guide the design of the next generation of hemoglobin-based oxygen carriers (HBOCs) for use in tissue engineering and transfusion medicine applications.

Pathogen inactivation of human serum facilitates its clinical use for islet cell culture and subsequent transplantation

Serum is regarded as an essential supplement to promote survival and growth of cells during culture. However, the potential risk of transmitting diseases disqualifies the use of serum for clinical cell therapy in most countries. Hence, most clinical cell therapy programs have replaced human serum with human serum albumin, which can result in inferior quality of released cell products. Photochemical treatment of different blood products utilizing Intercept® technology has been shown to inactivate a broad variety of pathogens of RNA and DNA origin. The present study assesses the feasibility of using pathogen-inactivated, blood group-compatible serum for use in human pancreatic islet culture. Isolated human islets were cultured at 37°C for 3-4 days in CMRL 1066 supplemented with 10% of either pathogen-inactivated or nontreated human serum. Islet quality assessment included glucose-stimulated insulin release (perifusion), ADP/ATP ratio, cytokine expression, and posttransplant function in diabetic nude mice. No differences were found between islets cultured in pathogen-inactivated or control serum regarding stimulated insulin release, intracellular insulin content, and ADP/ATP ratio. Whether media was supplemented with treated or nontreated serum, islet expression of IL-6, IL-8, MCP-1, or tissue factor was not affected. The final diabetes-reversal rate of mice receiving islets cultured in pathogen-inactivated or nontreated serum was 78% and 87%, respectively (NS). As reported here, pathogen-inactivated human serum does not affect viability or functional integrity of cultured human islets. The implementation of this technology for RNA- and DNA-based pathogen inactivation should enable reintroduction of human serum for clinical cell therapy.