Pharmacological approaches to reducing allogeneic blood exposure

Tranexamic Acid Is Associated With Improved Operative Field in Orthognathic Surgery

PURPOSE

In the past, both tranexamic acid and dexmedetomidine have been used separately to decrease intraoperative blood loss during orthognathic surgery. However, their combined use in the same setting has never been prospectively evaluated. The present study was conducted to evaluate the effect of tranexamic acid on operative field visibility and blood loss during orthognathic surgery after dexmedetomidine-induced hypotensive anesthesia.

PATIENTS AND METHODS

The present prospective, randomized clinical trial included patients who had undergone orthognathic surgery under general anesthesia. The patients were divided into 2 groups. The dexmedetomidine and tranexamic (DT) group received an intravenous bolus of tranexamic acid (15 mg/kg) and intravenous dexmedetomidine (0.25 to 0.7 μg/kg/hr) as maintenance infusion. The dexmedetomidine (DS) group received only intravenous dexmedetomidine at the same dosage. All the patients received a bolus dose of intravenous dexmedetomidine (1 μg/kg) before the start of anesthesia induction. The operating surgeon rated the quality of the surgical visual field every 15 minutes using the Fromme ordinal scale. Intraoperative blood loss was estimated using the modified gross formula. The operating surgeon's satisfaction was assessed using a Likert scale. Data were analyzed using SPSS, version 22.0 (IBM Corp, Armonk, NY). Kolmogorov-Smirnov tests were used to assess the normality of the measured data, and categorical variables were analyzed using the χ² or Fischer exact test.

RESULTS

The study sample included 36 patients, with a mean age of 23.67 ± 11.298 years in the DS group and 20.28 ± 3.286 years in the DT group. Of the patients in the DS and DT groups, 66.66 and 61.11% were male, respectively. No statistically significant differences were found in the baseline characteristics between the 2 treatment groups. The surgeon reported a significantly better surgical visual field in the DT group compared with that in the DS group (P = .001). Also, the intraoperative blood loss significantly less in the DT group (231.11 ± 137.64 mL vs 360.17 ± 187.86 mL; P = .025).

CONCLUSIONS

Tranexamic acid improved surgical field visibility and reduced intraoperative blood loss when administered in conjunction with dexmedetomidine during orthognathic surgery under controlled hypotensive anesthesia.

High-volume, Multilevel Local Anesthetics-Epinephrine Infiltration in Kyphoscoliosis Surgery: Blood Conservation

INTRODUCTION

Scoliosis surgery is usually associated with severe bleeding. Various systemic strategies for blood conservation were applied, while the local techniques get less attention. The preemptive use of sufficient volume for proper tissue infiltration at two levels was applied. The local epinephrine may control bleeding without reliance upon deliberate hypotension, permitting a higher tissue perfusion.

MATERIALS AND METHODS

This prospective study included 46 patients scheduled for posterior spinal fusion for scoliosis correction. Patients were randomized into two groups. group I received a cocktail of high volume (100 ml/each 10 cm of wound length) of local anesthetics and epinephrine tumescent infiltration at the subcutaneous (SC) followed by intramuscular level bilaterally. Group C received saline infiltration in the same technique. Statistically, data were analyzed according to its distribution using the t-test, Mann-Whitney, and Chi-square tests as appropriate.

RESULTS

There was a significant reduction in blood loss (38%), reduced blood and fluid transfusion (36% and 23%), and reduced operative time (23%), with higher surgeon satisfaction. The surgical field visibility (Fromme's scale) was much better during SC and muscular dissection in Group I, while it was fair during the bony work. The satisfactory field in spite of higher mean blood pressure in Group I greatly omitted the reliance upon deliberate hypotension.

CONCLUSION

The high-volume multilevel infiltration of epinephrine cocktail can provide a significant blood and operative time conservation in kyphoscoliosis surgery.

The efficacy of tranexamic acid for orthognathic surgery: a meta-analysis of randomized controlled trials

The efficacy of tranexamic acid in orthognathic surgery remains controversial. We conducted a systematic review and meta-analysis to explore the influence of tranexamic acid on blood loss for orthognathic surgery. We performed a search of PubMed, Embase, Web of science, EBSCO, and Cochrane library databases through October 2017 for randomized controlled trials (RCTs) assessing the effects of tranexamic acid versus placebo on orthognathic surgery. Meta-analysis was performed using the random-effects model. Six RCTs were included in the meta-analysis. Overall, compared with placebo in orthognathic surgery, tranexamic acid administration results in significantly decreased blood loss [mean difference (MD)=-159.73; 95% confidence interval (CI)=-236.42 to -83.03; P<0.0001], and higher postoperative haemoglobin (MD=0.71; 95% CI=0.11 to 1.31; P=0.02), but has no remarkable impact on postoperative haematocrit (MD=1.23; 95% CI=-1.22 to 3.69; P=0.33) and operation time (MD=-2.35; 95% CI=-18.05 to 13.36; P=0.77). In addition, patients with orthognathic surgery need decreased amounts of irrigant fluid (MD=-229.23; 95% CI=-399.63 to -58.83; P=0.008) after using tranexamic acid. We concluded that tranexamic acid promotes the bleeding control in orthognathic surgery.

The Efficacy of Preoperative Oral Tranexamic Acid on Intraoperative Bleeding During Rhinoplasty

BACKGROUND

Perioperative bleeding is a common side effect of rhinoplasty which may impose the blood transfusion to the patients. As a result of risks and cost of blood transfusion, this study is planned to reduce blood loss in these surgeries. Since tranexamic acid (TXA) has been reported to reduce bleeding and subsequent possible need for blood transfusion, the purpose of this study was to evaluate the efficacy of oral TXA on blood loss during rhinoplasty.

METHODS AND MATERIALS

In this double-blind, randomized, placebo-controlled clinical trial, 50 participants underwent rhinoplastic surgery. These participants were divided into 2 groups; 25 were randomly assigned to each 1. The patients in the first group received 1 g (2 × 500 mg) tranexamic acid tablets, and the patients in the second group received placebo 2 hours before starting the surgery. All patients were operated by the same surgical team and the same anesthetic techniques were used during the surgery. Gender, age, BMI, duration of operation, the amount of blood loss, and surgeon's satisfaction rate were the variables studied.

RESULTS

The first group (TXA group) consisted of 11 males (44%) and 14 females (56%) and the second group consisted of 13 males (52%) and 12 females (48%). There was no statistical difference in the distribution of the variables between the 2 groups, except for the blood loss, duration of operation, and surgeon's satisfaction. The mean total blood loss was 144.6 ± 60.28 mL in "group 1" and 199.6 ± 73.05 mL in "group 2" (P < 0.05). Duration of operation in the first group was less than the second group (2.60 ± 0.53 hours vs. 2.99 ± 0.59 hours) (P = 0.017). The surgeon was more satisfied with the quality of surgical field and visualization in "group 1" (3.76 ± 0.72) than "group 2" (2.16 ± 0.50) (P = 0.001).

CONCLUSION

The preoperative administration of 1 g oral tranexamic acid significantly decreased the blood loss in patients undergoing rhinoplastic surgery without any significant adverse effects.Iranian registry no:IRCT201312271674N10 (www.irct.ir).

Effect of tranexamic acid irrigation on perioperative blood loss during orthognathic surgery: a double-blind, randomized controlled clinical trial

PURPOSE

Perioperative hemorrhage is an important concern during orthognathic surgery. The purpose of this study was to assess the effect of tranexamic acid (TXA) irrigation on perioperative hemorrhage during orthognathic surgery.

MATERIALS AND METHODS

In this double-blind, randomized controlled clinical trial, 56 participants who underwent orthognathic surgery were divided into 2 groups. The patients in the first group received TXA irrigation with normal saline (1 mg/mL), and the patients in the second group had normal saline for irrigation during orthognathic surgery. Age, gender, operation duration, the amount of irrigation solution used, and preoperative hemoglobin, hematocrit, and weight were the variables that were studied. The use of TXA solution for irrigation was the predictive factor of the study.

RESULTS

Each group consisted of 28 patients. Group 1 consisted of 15 male patients (53.6%) and 13 female patients (46.4%) and group 2 consisted of 14 male patients (50%) and 14 female patients (50%). There was no difference in the distributions of the variables between the 2 groups, except for the duration of the operation. The mean duration of the operation was 3.94 ± 0.61 hours in group 1 and 4.17 ± 0.98 hours in group 2, and the difference in this respect between the 2 groups was statistically significant (P < .05). The mean intraoperative blood loss was 817.85 ± 261.83 mL in group 1 and 575.00 ± 286.90 mL in group 2 (P < .05). The mean volume of irrigation was 1,057.14 ± 407.04 mL in group 1 and 843.57 ± 275.48 mL in group 2 (P > .05).

CONCLUSIONS

TXA is effective in reducing intraoperative blood loss in patients for whom substantial blood loss is anticipated.

Surgical management in treatment of Jehovah's witness in trauma surgery in Indian subcontinent

The Jehovah's Witness religion is a Christian movement, founded in the US in the 1870s, with 7 million followers worldwide with only 0.002% in India. There is minimal to complete absence of awareness about the existence of this community in our society. Astonishing is that fact that among medical professionals, there is almost no awareness about this unique population, regarding the fact that they completely refuse of blood transfusion even if it leads to their death. This is integral to their faith. Besides legal and ethical issues in treating these group of patients, the biggest challenge exist even in the western world is their management in trauma scenario where few options exist. We have discussed the issues and recommendations in management in trauma scenario in our Indian subcontinent.

Evaluation of the efficacy of tranexamic acid on blood loss in orthognathic surgery. A prospective, randomized clinical study

The purpose of this prospective, randomized, double blind study was to assess the effect of tranexamic acid on blood loss, quality of surgical field and duration of surgery in adolescent orthognathic surgery patients. 50 consecutive patients, scheduled for orthognathic surgery were included. The study group (n=25) received tranexamic acid 10mg/kg as a bolus preoperatively followed by 1mg/kg as a maintenance dose intra operatively; the control group (n=25) received placebo (normal saline). All patients received moderate hypotensive anaesthesia with nitroglycerin and had surgery according to a standard protocol. Intra operative blood loss, duration of surgery, quality of surgical field, blood transfusion and complications, if any, were recorded. The mean total blood loss was 166.1±65.49ml in the study group and 256.4±77.80ml in the control group. The results showed statistically significant reduction in blood loss (p<0.001) and improved quality of surgical field (p<0.001) in the study group. There was no significant difference in duration of surgery and transfusion requirements between the two groups. In conclusion, preoperative and intra operative administration of the antifibrinolytic agent, tranexamic acid, is effective in controlling blood loss and improving the quality of the surgical field.

Reducing perioperative blood loss and allogeneic blood transfusion in patients undergoing major spine surgery

At present, individual techniques, including intraoperative acute normovolemic hemodilution, use of tranexamic acid, use of intrathecal morphine, proper positioning, and modification of operative techniques, seem most promising for reducing perioperative blood loss and allogeneic blood transfusion in patients undergoing major spine surgery. Other techniques including preoperative autologous predonation; mandatory discontinuation of use of antiplatelet agents; intraoperative and postoperative red-blood-cell salvage; use of aprotinin, epsilon-aminocaproic acid, recombinant factor VIIa, or desmopressin; induced hypotension; avoidance of hypothermia; and minimally invasive operative techniques require additional studies to either establish their effectiveness or address safety considerations.

Point of care testing in children undergoing cardiopulmonary bypass

BACKGROUND

Excessive hemorrhage is a major complication after cardiac surgery requiring cardiopulmonary bypass (CPB). The aim of this study was to define the potential role of the cone and platelet analyzer (CPA) and the rotating thromboelastogram (ROTEM) point of care tests in children undergoing CPB.

PROCEDURE

We prospectively studied 15 pediatric patients aged 1 month to 10 years. Blood count, blood coagulation tests (prothrombin time [PT], activated partial thromboplastin time, fibrinogen, thrombin time), CPA and ROTEM parameters were measured before and after CPB. Demographic and surgical data were recorded as were those on perioperative blood loss and blood product transfusion.

RESULTS

Low body weight, longer duration on CPB and lower core body temperature were associated with an increased bleeding risk. The ROTEM test showed a significant prolongation of clotting time and decreased maximal clot firmness (MCF) postoperatively in children with increased bleeding. The coagulation parameters associated with increased bleeding were: prolonged PT, lower fibrinogen levels, prior to surgery, and lower MCF after surgery. CPA test findings were not associated with postoperative bleeding in our patients.

CONCLUSIONS

CPA did not serve as a prognostic tool for predicting bleeding risk in children undergoing CPB. The change in ROTEM's post-CPB results associated with bleeding tendency, and they may predict for poorer clot formation and stability.

The impact of aprotinin on postoperative renal dysfunction in neonates undergoing cardiopulmonary bypass: a retrospective analysis

BACKGROUND

Recent concern about the safety of aprotinin administration to adults has led to its suspension from worldwide markets. However, few studies have examined its safety in pediatric patients. Studies in children evaluating aprotinin's safety have been hindered by the heterogeneity of pediatric patients and the inconsistency of clinical protocols. In this investigation, we retrospectively reviewed 200 neonatal cardiac surgical cases performed at our institution to examine the safety of aprotinin, focusing on postoperative renal dysfunction, using a consistent aprotinin dosing protocol.

METHODS

Two-hundred consecutive neonates scheduled for palliative or corrective congenital cardiac surgery requiring cardiopulmonary bypass (CPB) from January 1, 2005 through February 28, 2007 were included in this retrospective investigation. Preoperative, intraoperative and postoperative data were collected and analyzed. Markers of safety included 72-h postoperative renal dysfunction, need for dialysis (peritoneal or hemodialysis), thrombosis and in-hospital mortality.

RESULTS

Neonates were divided into those who received aprotinin (aprotinin group; n = 156) and those who did not (no aprotinin group; n = 44). Twenty-four and 72-h postoperative serum creatinine levels were significantly greater than baseline levels in both groups. The degree of change in creatinine levels was highly significant and similar between the two groups. A larger percentage of neonates in the aprotinin group developed renal dysfunction, although this difference was not statistically significant. Stepwise logistic regression, assessing the impact on renal dysfunction of all variables that indicated significance between neonates who did or did not receive aprotinin and between neonates who did or did not develop renal dysfunction, identified CPB time and age as significant predictors of postoperative renal dysfunction. All neonates who developed postoperative renal dysfunction had a CPB time of more than 100 min regardless of the use of aprotinin. Additionally, using this subset, similar percentages of renal dysfunction occurred in both groups. A second multivariable regression analysis to simultaneously account for the predictors of CPB time, age and aprotinin administration found CPB time to be the only significant predictor of renal dysfunction. Incidences of postoperative dialysis, postoperative thrombosis and in-hospital mortality were not statistically significantly different between the aprotinin and the no aprotinin groups.

CONCLUSION

The occurrence of postoperative renal dysfunction in neonates was more significantly predicted by the duration of CPB than by the intraoperative administration of aprotinin. CPB times of more than 100 min appeared to be a critical marker for the development of postoperative renal dysfunction. Randomized prospective trials are needed to confirm the validity of our retrospective findings.

Efficacy of FDA-approved hemostatic drugs to improve survival and reduce bleeding in rat models of uncontrolled hemorrhage

Several FDA-approved intravenous drugs are used to reduce surgical bleeding. This series of studies tested whether these drugs (aprotinin, desmopressin, tranexamic acid, epsilon-aminocaproic acid) could reduce bleeding due to traumatic injuries in two models of uncontrolled hemorrhage in rats. In the first phase of each study, a nonlethal tail bleeding model was used that incorporated limited fluid resuscitation (lactate Ringer's solution). Four doses of vehicle or the test substance were given successively with bleeding time and blood loss measured after each dose. In the second phase of each study, a lethal liver injury was produced by excising a section of the median lobe (approximately 0.8% of body weight) and an infusion of either vehicle or the test substance was immediately begun. This model included aggressive fluid resuscitation and a severe dilutional coagulopathy. Blood loss, survival time and mortality rate were recorded. Three studies were performed, testing each of the drugs singly and in combination. None of the drugs significantly reduced either bleeding time or blood loss in the tail bleeding model, nor were blood loss, survival time or mortality rate altered in the liver injury model. Taken together, these results suggest that these FDA-approved drugs, when used either singly or in combination, are not efficacious in these models of traumatic uncontrolled hemorrhage.

A decision aid for autologous pre-donation in cardiac surgery--a randomized trial

OBJECTIVES

The objective of this randomized, controlled study was to determine the usefulness of a decision aid on pre-donation of autologous blood before elective open heart surgery.

METHODS

The decision aid (DA) group received a tape and booklet which described the options for peri-operative transfusion in detail. The no decision aid (NDA) group received information usually given to patients about autologous donation.

RESULTS

A total of 120 patients were randomized. The DA group rated themselves better prepared for decision making and showed significant improvements in knowledge (p = 0.001) and realistic risk perceptions (p = 0.001). In both groups there was an increase in the proportion of patients choosing allogeneic blood between baseline and follow-up (p = 0.001). Patients in the DA group were significantly more satisfied with the amount of information they received, how they were treated and with the decision they made, than patients in the NDA group.

CONCLUSION

The decision aid is useful in preparing patients for decision making.

PRACTICE IMPLICATIONS

The next stage is to explore strategies to make it available to all appropriate patients.

A propensity score case-control comparison of aprotinin and tranexamic acid in high-transfusion-risk cardiac surgery

BACKGROUND

Cardiac surgery with cardiopulmonary bypass may result in excessive fibrinolysis and platelet (PLT) dysfunction, resulting in impaired hemostasis and excessive blood loss. Prophylactic use of the antifibrinolytic drugs aprotinin and tranexamic acid is thought to prevent these hemostatic defects. Their relative clinical utility and safety in high-transfusion-risk cardiac surgery, however, is not known.

STUDY DESIGN AND METHODS

Using propensity scores, 449 patients who received aprotinin for high-transfusion-risk cardiac surgery were matched to 449 patients who received tranexamic acid from a pool of 10,870 consecutive patients who underwent cardiac surgery at a single center, 586 of whom received aprotinin and the remainder of whom received tranexamic acid.

RESULTS

The two matched groups were well balanced in terms of measured perioperative variables. Blood product transfusion rates were similar in the aprotinin and tranexamic acid groups: red blood cells, 79 percent versus 76 percent (p = 0.3); PLTs, 56 percent versus 50 percent (p = 0.06); and plasma, 66 percent versus 61 percent (p = 0.1). Adverse events rates were comparable in the two groups, except for renal dysfunction (defined as a greater than 50% increase in creatinine concentration during the first postoperative week to >100 micromol/L in women and >110 micromol/L in men or a new requirement for dialysis support), which occurred in 24 percent (107/449) of aprotinin patients and 17 percent (75/449) of tranexamic acid patients (p = 0.01).

CONCLUSIONS

Aprotinin and tranexamic acid have similar hemostatic effectiveness in high-transfusion-risk cardiac surgery. Within the confines of propensity score matching, our results suggest that aprotinin may be associated with renal dysfunction.

New developments in pediatric cardiac anesthesia

As the practice of pediatric cardiac anesthesia continues to grow, anesthesiologists now routinely care for patients ranging in size from less than 2 kg to more than 100 kg. New clinical and laboratory research has enhanced our understanding of the effects of anesthetic drugs on the pediatric myocardium, and improvements in survival statistics for even the smallest and sickest infants have shifted the emphasis to evaluation of quality of life and neurological outcome in pediatric cardiac patients. The use of circulatory support in infants and children, both for rapid resuscitation and for more chronic indications such as bridge to transplantation, also continues to evolve, with the recent introduction of pulsatile and axial pumps for pediatric use. This article reviews anesthetic agents, bleeding and coagulation, neurological monitoring, and mechanical circulatory support in the treatment of infants and children.

Management of bleeding emergencies: when to use recombinant activated Factor VII

Recombinant activated Factor VII (rVIIa) was originally released as a clotting factor, with use limited to a select group of patients who had few other treatment options. Due to the apparent ability of rVIIa to stop bleeding, no matter what the underlying cause, there is great interest in use of rVIIa in a wide range of bleeding patients. This article discusses rVIIa and its uses in a variety of patients, especially liver disease and trauma patients, and makes suggestions for appropriate use. Although most of the reports on rVIIa are anecdotes and case series, there is increasing data for clinical trials to help guide usage.

Tranexamic acid reduces allogeneic red cell transfusions in patients undergoing total knee arthroplasty: results of a meta-analysis of randomized controlled trials

BACKGROUND

The delayed bleeding associated with total knee arthroplasty (TKA) may be a result of a tourniquet-induced imbalance of the procoagulant and fibrinolytic systems. There are conflicting results in the literature about tranexamic acid (TA) infusion in reducing postoperative blood loss and the number of transfused red cells (RBC) units. A meta-analysis was performed to summarize the results of different research studies.

STUDY DESIGN AND METHODS

Randomized controlled trials reported through October 2004 were retrieved, and nine studies met the criteria for meta-analysis. Summary odds ratio (OR) of allogeneic transfusion and a weighted mean difference (WMD) of transfusions per patient in TA-treated group versus placebo group were calculated across studies.

RESULTS

The use of TA significantly reduced the proportion of patients requiring blood transfusion (summary OR, 0.10; 95% CI, 0.06-0.18; p < 0.00001) and the number of RBC transfusions per patient (WMD, -1.72; 95% CI, -2.11 to -1.33; p < 0.00001) when compared with patients who received placebo.

CONCLUSION

Our meta-analysis shows that the use of TA for patients undergoing TKA is effective in reducing the requirements of allogeneic blood transfusion.

Evidence-based review of the role of aprotinin in blood conservation during orthopaedic surgery

Aprotinin is a serine protease inhibitor with antifibrinolytic properties that has been approved as a blood-conserving drug in cardiac surgery by the United States Food and Drug Administration. On the basis of the current evidence from Level-I trials, we make a grade-A recommendation for use of the high-dose aprotinin regimen in hip and spine surgery. Because of conflicting data, the low-dose aprotinin therapy as well as the use of aprotinin in patients with cancer cannot be recommended (grade-I recommendation). High-quality randomized trials are necessary to determine the optimal (and minimal) therapeutic dose of aprotinin and the optimal time of aprotinin administration during surgery.

Anaesthesia for correction of scoliosis in children

Surgical correction of spinal deformities in children presents a challenge to the anaesthetist because of the extensive nature of the surgery, the co-morbidities of the patients and the constraints on anaesthetic techniques of intraoperative neurophysiological monitoring of the spinal cord. Adolescent idiopathic scoliosis is the most common deformity. Patients with scoliosis secondary to neuromuscular conditions are at greatest risk of perioperative problems, particularly excessive blood loss and respiratory failure. The risk of spinal cord damage can be decreased by the use of intraoperative spinal cord monitoring, particularly monitoring of the lower limb compound muscle action potential evoked by transcranial electrical stimulation. Specific anaesthetic techniques are required for this monitoring to be reliable. Because of concerns about spinal cord perfusion there is now less reliance on induced hypotension and haemodilution to reduce blood loss, with emphasis on proper patient positioning, controlled haemodynamics and antifibrinolytic therapy. Effective postoperative pain management requires a multimodal approach.

Guidelines for the use of recombinant activated factor VII (rFVIIa) in uncontrolled bleeding: a report by the Israeli Multidisciplinary rFVIIa Task Force

BACKGROUND

Recombinant activated factor VII (rFVIIa) has been approved by the U.S. Food and Drug Administration (FDA) for almost a decade for hemophilic patients with inhibitors. Its off-label use as a hemostatic agent in massive bleeding caused by a wide array of clinical scenarios is rapidly expanding. While evidence-based guidelines exist for rFVIIa treatment in hemophilia, none are available for its off-label use.

OBJECTIVES

The aim of this study is to develop expert recommendations for the use of rFVIIa in patients suffering from uncontrolled bleeding (with special emphasis on trauma) until randomized, controlled trials allow for the introduction of more established evidence-based guidelines.

METHODS

A multidisciplinary task force comprising representatives of the relevant National Medical Associations, experts from the Medical Corps of the Army, Ministry of Health and the Israel National Trauma Advisory Board was established in Israel. Recommendations were construed based on the analysis of the first 36 multi-trauma patients accumulated in the prospective national registry of the use of rFVIIa in trauma, and an extensive literature search consisting of published and prepublished controlled animal trials, case reports and series. The final consensus guidelines, together with the data of the first 36 trauma patients treated in Israel, are presented in this article.

RESULTS

Results of the first 36 trauma patients: The prolonged clotting assays [prothrombin time (PT) and partial thromboplastin time (PTT)] shortened significantly within minutes following administration of rFVIIa. Cessation of bleeding was achieved in 26 of 36 (72%) patients. Acidosis diminished the hemostatic effect of the drug, while hypothermia did not affect it. The survival rate of 61% (22/36) seems to be favorable compared with published series of similar, or less severe, trauma patients (range 30%-57%).

CONCLUSIONS

As a result of the lack of controlled trials, our guidelines should be considered as suggestive rather than conclusive. However, they provide a valuable tool for physicians using rFVIIa for the expanding off-label clinical uses.

Perioperative systemic haemostatic agents

Skilful surgery combined with blood-saving methods and careful management of blood coagulation will all help reduce unnecessary blood loss and transfusion requirements. Excessive surgical bleeding causes hypovolaemia, haemodynamic instability, anaemia and reduced oxygen delivery to tissues, with a subsequent increase in postoperative morbidity and mortality. The role of anaesthetists in managing surgical blood loss has increased greatly in the last decade. Position of the patient during surgery and the provision of a hypotensive anaesthetic regimen were once considered the most important contributions of the anaesthetist to decreasing blood loss. Now, several pharmacological haemostatic agents are being used by anaesthetists as blood-saving agents. After a brief discussion of the physiology of haemostasis, this article will review the evidence for the role of such agents in reducing perioperative blood loss and transfusion requirements.

Care of the injured Jehovah's Witness patient: Case report and review of the literature

Care for the Jehovah's Witness patient can be a challenge and often a dilemma to clinicians because of the patient's religious beliefs and teachings against receiving blood and blood products, especially in emergency or trauma settings. We present a case of a severely injured elderly Jehovah's Witness patient who survived. We also review the literature and offer an organized approach to care for such patients.

What is the evidence for using hemostatic agents in surgery?

The pharmacological methods used to achieve systemic hemostasis have generated much discussion due to concerns of serious adverse effects (e.g., thromboembolic complications) and costs of therapy in addition to efficacy considerations. There are a limited number of well-controlled trials involving pharmacological hemostasis for spine surgery. In the largest double-blinded randomized controlled trial to date involving spine surgery, there was a trend toward reduced homologous transfusion in patients receiving aprotinin, but the only statistically significant result ( p<0.001) was a reduction in autologous red cell donations. The findings of this trial are important, since the investigators used a number of restrictive transfusion strategies (e.g., autologous donation, low hematocrit trigger for transfusion, blood-salvaging procedures with the exception of no cell saver) that were not always employed in earlier trials involving hemostatic agents. Smaller studies involving antifibrinolytic agents other than aprotinin have demonstrated reductions in blood loss and transfusion requirements in patients undergoing spine surgery, although the results were not always statistically significant. A very large randomized trial would be required to address comparative medication- and transfusion-related adverse events; such a trial involving patients undergoing cardiac surgery is currently being performed. Additionally, cost-effectiveness analyses are needed to help define the role of these agents based on the data that is available.

An overview of blood-sparing techniques used in spine surgery during the perioperative period

The problems linked to blood loss and blood-sparing techniques in spine surgery have been less studied than in other fields of orthopedics, such as joint-replacement procedures. Decreasing bleeding is not only important for keeping the patient's hemodynamic equilibrium but also for allowing a better view of the surgical field. In spine surgery the latter aspect is especially important because of the vicinity of major and highly fragile neurologic structures. The techniques and agents used for hemostasis and blood sparing in spinal procedures are mostly similar to those used elsewhere in surgery. Their use is modulated by the specific aspects of spinal approach and its relation to the contents of the spinal canal. Blood-sparing techniques can be divided into two categories based on their goals: either they are aimed at decreasing the bleeding itself, or they are aimed at decreasing the need for homologous transfusion. Various hemodynamic techniques, as well as systemic and local drugs and agents, can be used separately or in combination, and their use in the field of spine surgery is reported. The level of evidence for the efficacy of many of those methods in surgery as a whole is limited, and there is a lack of evidence for most of them in spine surgery. However, several blood-saving procedures and drugs, as well as promising new agents, appear to be efficient, although their efficacy has yet to be assessed by proper randomized controlled trials.

Aprotinin and major orthopedic surgery

Aprotinin is a potent pharmacological agent that reduces bleeding and limits blood transfusion requirements in current surgical practice. Many studies have been conducted in orthopedic surgery. In several trials performed in total hip replacement (THR) and total knee replacement (TKN) patients, aprotinin only moderately decreased blood-loss-replacement requirements. Conversely, when aprotinin was used in patients at high risk for bleeding (cancer, sepsis, redone surgery), it developed a potent hemostatic activity and decreased blood transfusion significantly. No increase in deep vein thrombosis and pulmonary embolism was observed. The only major side effect could be the potential occurrence of an anaphylactoid reaction. Prophylactic administration of aprotinin should be considered in extensive spine surgery and in high-risk major orthopedic operations. The decision to use aprotinin should be guided by a risk/benefit analysis.

A direct antifibrinolytic agent in major orthopedic surgery

Aprotinin is a potent pharmacological agent that reduces bleeding. In current surgical practices, the rate of blood transfusions has decreased with the use of aprotinin. Recently, studies using aprotinin have been conducted in orthopedic surgery. Several trials have been performed in patients undergoing total hip replacement and total knee replacement. Aprotinin moderately decreased blood loss in these patients. When aprotinin was used in patients with a high-risk of bleeding (ie, patients with cancer, sepsis, or undergoing reoperation), potent hemostatic activity occurred and the rate of blood transfusions significantly decreased. No increase in deep vein thrombosis and pulmonary embolism was observed. One adverse effect was the potential occurrence of an anaphylactoid reaction. Prophylactic administration of aprotinin should be considered in extensive spine surgery and in high-risk orthopedic operations. The decision to use aprotinin can be guided by a risk/benefit analysis.

[Pharmacological alternatives to blood transfusion: what is new about?]

Pharmacological approaches to reduce blood transfusion include the protease inhibitor aprotinin, lysine-analogue antifibrinolytics synthetic arginine-vasopressin derivatives (DDAVP) and recombinant factor VII (rfVIIa). These agents are known to prevent the need for blood after major surgery (cardiac, hepatic, and orthopaedic). Among the nonhemostatic agents erythropoietin (EPO) may be effective to reduce blood requirements in medical and surgical patients. Aprotinin is consistently effective in reducing blood transfusion in cardiac and hepatic surgical procedures, but there is little data to support its use in elective orthopaedic surgery. Antifibrinolytics show no evidence of efficacy in cardiac and hepatic surgery and its use is not warranted in orthopaedic surgery. Limited data suggest that DDAVP may be effective when a defect in platelet function is demonstrated. rFVIIa emerges as a promising haemostatic agent with proven benefit to reduce bleeding in haemophiliacs with inhibitors but might also be effective in patients with thrombocytopenia and thrombopathy, as well as in life-threatening hemorrhage in postsurgical patients. Ongoing studies will established its role a possible "universal haemostatic agent". Hematopoietic cytokines, such as EPO, may have a place to avoid blood transfusion in a variety of clinical conditions, including cancer and critically ill patients.

'Last-ditch' use of recombinant factor VIIa in patients with massive haemorrhage is ineffective

BACKGROUND AND OBJECTIVES

The aim of this retrospective study was to assess the effect of activated recombinant factor VII (rFVIIa) on the natural history of massive transfusion episodes.

MATERIALS AND METHODS

During 2002, outcome parameters were assessed in 50 patients transfused with more than 10 units of packed red cells. The effect of the addition of rFVIIa in 10 patients, with intractable bleeding, was then observed.

RESULTS

Overall mortality was 20% at 24 h and 34% at 7 days. Severe coagulopathy was confirmed as a serious negative prognostic factor and occurred in 42% of patients overall, but in 70% of rFVIIa-treated patients. Transient cessation or reduction of bleeding was noted in 60% of patients following rFVIIa infusion. However, 24-h and 7-day mortality rates were 40% and 70%, respectively, in this group.

CONCLUSIONS

Last-ditch rFVIIa therapy in patients resistant to conventional treatment did not rescue these patients or significantly alter outcomes.