Aprotinin reduces blood loss and the need for transfusion in orthognathic surgery

Optimizing drug regimens and supplementation in orthognathic surgery: A comprehensive and practical guide

OBJECTIVE

This study aimed to comprehensively review the literature and provide a practical guide for optimizing drug regimens and supplementation related to orthognathic surgery.

METHODS

The authors conducted a thorough review of the existing literature, following the PRISMA-ScR guidelines. Various types of studies except case reports and reviews were included. The study applied specific inclusion criteria, focusing on perioperative and/or postoperative drugs, medications, or supplementation related to orthognathic surgery.

RESULTS

This guide included 78 studies on various medications in orthognathic surgery. It encompasses clinical trials, cohort studies, cross-sectional studies, prospective and retrospective studies. The topics covered include antibiotics, analgesics, corticosteroids, antiemetics, hemostatic agents, local anesthetics, herbal medicine, and botulinum toxin. Pain and edema control involved specific medications, while local anesthesia utilized ropivacaine and bupivacaine. The guide also discusses mineral and vitamin supplementation. The effectiveness of hemostatic agents and antiemetics was highlighted.

CONCLUSION

Pain management, reduced swelling, enhanced wound healing, and faster recovery are among the advantages. In addition to the standard drugs and medications, the inclusion of vitamin and mineral supplements, tranexamic acid, postoperative anesthetic blocks, and preemptive antiemetics is anticipated to offer various benefits in orthognathic surgery, despite the limited available evidence.

Systematic mapping review of orthognathic surgery

STUDY DESIGN

Systematic mapping review AIM AND SCOPE: The objective of this mapping review was to identify, describe, and organize clinical research currently available from systematic reviews and primary studies regarding co-interventions and different surgical modalities used in orthognathic surgery (OS) and their outcomes.

METHODS

Systematic reviews (SRs), randomized controlled trials, and observational studies that evaluated perioperative OS co-interventions and surgical modalities were identified in an exhaustive search of MEDLINE, EMBASE, Epistemonikos, Lilacs, Web of Science, and CENTRAL. Grey literature was also screened.

RESULTS

Included were 35 SRs and 253 primary studies, 103 from SRs, and another 150 identified in our search. Overall, SR quality was rated as critically low, with only two SRs rated as of high quality. 19 questions on population, interventions, comparisons, and outcomes (PICO) extracted from the SRs focused on osteosynthesis methods, surgical cutting devices, and use of antibiotics, corticosteroids, and induced hypotension. Also identified were 15 research gaps. Evidence bubble maps were created to graphically depict the available evidence.

CONCLUSION

Future high-quality research, both primary and secondary, is needed to address the knowledge gaps identified in this systematic mapping review.

Bone marrow space volume of the mandible influencing intraoperative blood loss in bilateral sagittal split osteotomy: A pilot Study

The aim of this study was to investigate whether the bone marrow space volume of the mandible affects blood loss during bilateral sagittal split osteotomy (BSSO). Sixteen patients who underwent BSSO in our hospital were included in this study. Bone marrow space volume of the mandible was measured by analyzing images from computed tomography. Blood loss during BSSO was measured by weighing gauze, measuring suctioned blood, and adjusting for the volume of irrigation solution used during BSSO. Mean blood loss during BSSO for the 16 patients was 200.5 ml, and patients were divided into: Group I, with less than mean blood loss; and Group II, with greater than mean blood loss. Total bone marrow space volume was significantly greater in Group II (12,450.7 ± 2644.3 mm³) than in Group I (9130.3 ± 3005.8 mm³; P<0.05). A correlation between bone marrow space volume and blood loss during BSSO was suggested, and these results are beneficial for surgeons planning and preparing the orthognathic surgery.

Effect of hydroxyethyl cellulose soluble hemostatic gauze on hemostasis in facial contouring surgery

BACKGROUND

In facial contour surgery, due to the narrow field of vision in the oral approach and the abundant blood supply to the maxillofacial area, hemostasis is not easy. The purpose of this study was to evaluate the hemostatic effect of soluble hemostatic gauze.

METHODS

We organized a prospective randomized study of 282 patients receiving facial contouring surgery (4 types of procedures in total) during 2016.1.1 to 2018.12.30. For each type of procedure, patients were randomly divided into study group (received hemostatic gauze) and control group (received sterile gauze). Two groups were compared for each type of procedure regarding 5 major perioperative variables: intraoperative blood loss, operation time, 24-hour postoperative drainage volume, total postoperative drainage volume, and postoperative drainage time. Correlation between variables was analyzed.

RESULTS

Compared with control group, the study group had higher amount of intraoperative blood loss in mandibular angle ostectomy (MAO) (P < .01) and mandibular angle-body-chin curved ostectomy procedures (P < .05), less total postoperative drainage volume in MAO (P < .01) but not in malarplasty with MAO and partial masseter muscle resection along with MAO procedures. No significant difference was observed between respective study and control groups regarding operation time, 24-hour postoperative drainage volume, and postoperative drainage time in any of the 4 types of surgery. In all 4 types of procedures, a strongly positive correlation was observed between total drainage volume and 24-hour drainage volume in both the study and control groups (r: 0.88-0.97, P < .01).

CONCLUSION

The effect of hydroxyethyl cellulose soluble hemostatic gauze on hemostasis in facial contouring surgery is associated with the type of surgery, which can reduce the risk of postoperative bleeding in MAO. However, for surgery with relatively large amount of intraoperative and postoperative bleeding, the hemostatic gauze had a limited postoperative hemostasis efficacy, which needs further evaluation.

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.

Systematic review of thromboprophylaxis in patients having orthognathic surgery

Orthognathic surgery is an elective procedure that is done in healthy individuals so complications such as thromboembolic events are rare. Pharmacological thromboprophylaxis, which reduces the risk of these events, may also increase blood loss and potentially the risk of life-threatening haemorrhage, so a state of clinical equipoise exists about whether it should be given routinely. We systematically reviewed published papers to identify the incidence of venous thromboembolism and haemorrhage in patients treated by orthognathic surgery who were, and were not, given pharmacological thromboprophylaxis. The pooled incidence of thromboembolic events was 0% in those who were, and 0.19% in those who were not. Return to theatre to control bleeding was required in 2.72% of the patients treated at centres where it was given, and in 0.55% at those where it was not. Small sample sizes, the heterogeneity of treatment protocols, and incomplete reporting made further statistical analysis impossible. The incidence of venous thromboembolism in patients who have orthognathic surgery is low when compared with the rest of the hospital population. Although pharmacological thromboprophylaxis may further reduce this, it can also increase blood loss, and uncertainty therefore remains over the best protocol for its routine use. The risk stratification of individual patients, and large randomised controlled trials are now required to establish the best treatment.

The Role of Antifibrinolytics in Reducing Blood Loss During Craniofacial or Orthognathic Surgical Procedures: A Meta-Analysis

PURPOSE

Use of antifibrinolytic drugs in craniofacial and orthognathic surgery seems quite promising and has strong advocates. However, supporting evidence is controversial and limited by a small sample of individual studies. We sought to systematically review and meta-analyze the available data regarding the role of preoperative or intraoperative antifibrinolytic drugs (eg, tranexamic acid, aprotinin, or aminocaproic acid) in craniofacial and orthognathic surgery.

MATERIALS AND METHODS

We searched PubMed, Scopus, Embase, the Cochrane Library, and Web of Science through April 19, 2018, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Outcomes of interest included the volume of blood loss, volume of transfusions, and operative time. A meta-analysis was performed with a random-effects model using Review Manager (RevMan) software (The Cochrane Collaboration, Copenhagen, Denmark).

RESULTS

We identified 32 eligible studies with 749 patients undergoing craniofacial surgery and 546 undergoing orthognathic surgery. Meta-analysis showed that antifibrinolytic use led to statistically significant decreases in blood loss and blood transfusions for craniofacial procedures in adult or pediatric patients and to significantly less blood loss during orthognathic surgical procedures. Operative time did not significantly differ for either type of surgery.

CONCLUSIONS

Antifibrinolytics can significantly reduce blood loss in craniofacial surgical procedures including pediatric craniosynostosis and adult rhinoplasties and in orthognathic surgical procedures, as well as transfusion requirements in pediatric craniofacial surgical procedures. However, the clinical significance of the medications is still questionable because of the relative paucity of information on adverse effects and the usual small volume loss during those operations.

The effect of different dosage regimens of tranexamic acid on blood loss in bimaxillary osteotomy: a randomized, double-blind, placebo-controlled study

The purpose of this study was to compare the effects of three dosage regimens of intravenous tranexamic acid and normal saline placebo on blood loss and the requirement for transfusion during bimaxillary osteotomy. A prospective, randomized, double-blind, placebo-controlled study was performed. Eighty patients scheduled for elective bimaxillary osteotomy were divided into four groups: a placebo group and three groups receiving a single dose of tranexamic acid 10, 15, or 20mg/kg body weight after the induction of anaesthesia. Demographic data, the anaesthetic time, the operative time, and the experience of the surgical team were similar in the four groups. Patients receiving placebo had increased blood loss compared to those receiving tranexamic acid. No significant difference in blood loss was found among those who received 10, 15, or 20mg/kg body weight of tranexamic acid. There was no significant difference in transfusion requirement, amount of 24-h postoperative vacuum drainage, length of hospital stay, or complications among the four groups. Prophylactic tranexamic acid decreased bleeding during bimaxillary osteotomy. Of the three dosages of tranexamic acid studied, the most efficacious and cost-effective dose to reduce bleeding was 10mg/kg body weight.

Quantitative analysis of facial soft tissue perfusion during hypotensive anesthesia using laser-assisted indocyanine green fluorescence angiography

The aim of this study was to quantitatively evaluate the efficacy of induced hypotensive anesthesia in decreasing facial soft tissue perfusion during orthognathic surgery using laser-assisted indocyanine green fluorescence angiography. This retrospective study involved the evaluation of 16 patients who underwent orthognathic surgery. Data collection included facial tissue perfusion of the bilateral cheeks and chin at normotension and with pharmacologically induced hypotensive anesthesia. There were statistically significant differences in the facial tissue perfusion at normal and depressed levels of blood pressure (P<0.001). This study used an objective measure to demonstrate the long-standing belief that hypotensive anesthesia is efficacious in reducing tissue perfusion in the surgical field. The data suggest that pharmacologically depressing the level of mean arterial pressure by 18% may result in a 41-52% decrease in facial soft tissue perfusion. This study reports a novel method of quantitative analysis.

Perioperative red blood cell transfusion in orofacial surgery

In the field of orofacial surgery, a red blood cell transfusion (RBCT) is occasionally required during double jaw and oral cancer surgery. However, the question remains whether the effect of RBCT during the perioperative period is beneficial or harmful. The answer to this question remains challenging. In the field of orofacial surgery, transfusion is performed for the purpose of oxygen transfer to hypoxic tissues and plasma volume expansion when there is bleeding. However, there are various risks, such as infectious complications (viral and bacterial), transfusion-related acute lung injury, ABO and non-ABO associated hemolytic transfusion reactions, febrile non-hemolytic transfusion reactions, transfusion associated graft-versus-host disease, transfusion associated circulatory overload, and hypersensitivity transfusion reaction including anaphylaxis and transfusion-related immune-modulation. Many studies and guidelines have suggested RBCT is considered when hemoglobin levels recorded are 7 g/dL for general patients and 8-9 g/dL for patients with cardiovascular disease or hemodynamically unstable patients. However, RBCT is occasionally an essential treatment during surgeries and it is often required in emergency cases. We need to comprehensively consider postoperative bleeding, different clinical situations, the level of intra- and postoperative patient monitoring, and various problems that may arise from a transfusion, in the perspective of patient safety. Since orofacial surgery has an especially high risk of bleeding due to the complex structures involved and the extensive vascular distribution, measures to prevent bleeding should be taken and the conditions for a transfusion should be optimized and appropriate in order to promote patient safety.

Operative time, blood loss, hemoglobin drop, blood transfusion, and hospital stay in orthognathic surgery

PURPOSE

This study was conducted to evaluate the operative time, blood loss, hemoglobin drop, blood transfusion, and length of hospital stay in orthognathic surgery.

METHODS

A 10-year retrospective analysis was performed on patients who underwent bilateral sagittal split osteotomy (with or without genioplasty), Le Fort I osteotomy (with or without genioplasty), or any combination of these procedures. A total of 271 patients were included.

RESULTS

The age range was 17 to 49 years, with a mean age of 24.13 ± 4.51 years. Approximately 62% of patients underwent double-jaw surgery. The most common procedure was bilateral sagittal split with Le Fort I (37%). The average operative time was 3.96 ± 1.25 h. The mean estimated blood loss was 345.2 ± 149.74 mL. Approximately 9% of patients received intraoperative blood transfusion. The mean hemoglobin drop in the non-transfusion cases was 2.38 ± 0.89 g/dL. The mean postoperative hospital stay was 1.85 ± 0.83 days. Only one patient was admitted to the ICU for one night.

CONCLUSIONS

In orthognathic surgery, blood loss is relatively minor, blood transfusion is frequent, and ICU admission is unlikely. Operative time, blood loss, blood transfusion, and the complexity of the surgical procedure can significantly increase the length of hospital stay. Males may bleed more than females in orthognathic surgery. Hemoglobin drop can be overestimated due to hemodilution in orthognathic surgery, which may influence the decision to use blood transfusion.

Assessment of hematologic parameters before and after bimaxillary orthognathic surgery

PURPOSE

The purpose of the study was to evaluate changes of hematologic parameters in bimaxillary surgery.

METHODS

Fifty-three patients were prospectively evaluated and divided into groups based on the surgical procedure and sex (predictor variables). Hemoglobin, red blood cells, hematocrit, and platelet were the primary outcome variables, operation time the secondary outcome, and the patients' age and weight the other variables.

TRIAL REGISTRATION

NCT02364765 (U.S. National Institutes of Health, clinicaltrials.gov).

RESULTS

There was statistically significant difference between all hematologic parameters before and after surgery, for both men and women, and for all surgical groups. There was a positive correlation between operative time and the decrease (in %) of the hematologic parameters. Linear regression analysis suggested that the Hb values decrease 0.083 % for every minute increase in the operation time, and 0.066, 0.066, and 0.010 % for RBC, Hct, and platelet count, respectively. There was a negative correlation between weight and all hematologic parameters. Correlations between age and hematologic parameters were not statistically significant. Almost all correlations between age, weight, sex, and the surgery group and the hematologic parameters were considered as very weak. Only one patient was transfused.

CONCLUSIONS

It is suggested that operation time and patient's weight play a bigger role than patient's age and sex in the decrease of hematologic parameters after bimaxillary surgery.

Prevention of Bleeding in Orthognathic Surgery--A Systematic Review and Meta-Analysis of Randomized Controlled Trials

PURPOSE

The objective of the present study was to evaluate the efficacy of hemostatic adjuncts on intraoperative blood loss (IOB) in orthognathic surgery (OS) detected by randomized controlled trials (RCTs) of the highest quality.

MATERIALS AND METHODS

A search of the Medline, Cochrane, Embase, and Web of Science databases was performed in January 2015, and the risk of bias was assessed using the Jadad and Delphi scales. The predictor variable was the hemostatic measures, and the main outcome variable was the total IOB volume. The secondary outcome variables were the hemoglobin and hematocrit and operating time. This review is registered at PROSPERO (CRD42014014840).

RESULTS

Eleven trials were included for review. The individual trials demonstrated the effects on IOB from hypotensive anesthetic regimens, the use of aprotinin, and the herbal medicine Yunnan Baiyao. Six studies of tranexamic acid (TXA), with 288 patients, were suitable for a meta-analysis of continuous data. TXA reduced IOB by an average of 171 mL (95% confidence interval [CI] -230 to -112; P < .00001). Its topical use yielded similarly significant results (mean difference -197, 95% CI -319 to -76; P < .001). A subgroup analysis showed a decreased operating time in the TXA groups by an average of 15 minutes (mean difference -14.78, 95% CI -22.21 to -7.35; P < .0001).

CONCLUSIONS

Efficient hemostatic adjuncts exist for OS. Our meta-analysis showed that TXA significantly reduces IOB by an average of one third, regardless of whether it was given intravenously (IV) or applied topically. Additional RCTs are needed to confirm the effect of topical TXA in OS, and larger studies of intravenous administration are needed before any routine recommendations. No hemostatic effect of hypotensive anesthesia was found, mainly owing to imprecise descriptions of the blinding procedures. Transparent and uniform trial reporting is thus encouraged in future studies.

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.

Anti-fibrinolytic use for minimising perioperative allogeneic blood transfusion

BACKGROUND

Concerns regarding the safety of transfused blood have led to the development of a range of interventions to minimise blood loss during major surgery. Anti-fibrinolytic drugs are widely used, particularly in cardiac surgery, and previous reviews have found them to be effective in reducing blood loss, the need for transfusion, and the need for re-operation due to continued or recurrent bleeding. In the last few years questions have been raised regarding the comparative performance of the drugs. The safety of the most popular agent, aprotinin, has been challenged, and it was withdrawn from world markets in May 2008 because of concerns that it increased the risk of cardiovascular complications and death.

OBJECTIVES

To assess the comparative effects of the anti-fibrinolytic drugs aprotinin, tranexamic acid (TXA), and epsilon aminocaproic acid (EACA) on blood loss during surgery, the need for red blood cell (RBC) transfusion, and adverse events, particularly vascular occlusion, renal dysfunction, and death.

SEARCH STRATEGY

We searched: the Cochrane Injuries Group's Specialised Register (July 2010), Cochrane Central Register of Controlled Trials (The Cochrane Library 2010, Issue 3), MEDLINE (Ovid SP) 1950 to July 2010, EMBASE (Ovid SP) 1980 to July 2010. References in identified trials and review articles were checked and trial authors were contacted to identify any additional studies. The searches were last updated in July 2010.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of anti-fibrinolytic drugs in adults scheduled for non-urgent surgery. Eligible trials compared anti-fibrinolytic drugs with placebo (or no treatment), or with each other.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. This version of the review includes a sensitivity analysis excluding trials authored by Prof. Joachim Boldt.

MAIN RESULTS

This review summarises data from 252 RCTs that recruited over 25,000 participants. Data from the head-to-head trials suggest an advantage of aprotinin over the lysine analogues TXA and EACA in terms of reducing perioperative blood loss, but the differences were small. Compared to control, aprotinin reduced the probability of requiring RBC transfusion by a relative 34% (relative risk [RR] 0.66, 95% confidence interval [CI] 0.60 to 0.72). The RR for RBC transfusion with TXA was 0.61 (95% CI 0.53 to 0.70) and was 0.81 (95% CI 0.67 to 0.99) with EACA. When the pooled estimates from the head-to-head trials of the two lysine analogues were combined and compared to aprotinin alone, aprotinin appeared more effective in reducing the need for RBC transfusion (RR 0.90; 95% CI 0.81 to 0.99).Aprotinin reduced the need for re-operation due to bleeding by a relative 54% (RR 0.46, 95% CI 0.34 to 0.62). This translates into an absolute risk reduction of 2% and a number needed-to-treat (NNT) of 50 (95% CI 33 to 100). A similar trend was seen with EACA (RR 0.32, 95% CI 0.11 to 0.99) but not TXA (RR 0.80, 95% CI 0.55 to 1.17). The blood transfusion data were heterogeneous and funnel plots indicate that trials of aprotinin and the lysine analogues may be subject to publication bias.When compared with no treatment aprotinin did not increase the risk of myocardial infarction (RR 0.87, 95% CI 0.69 to 1.11), stroke (RR 0.82, 95% CI 0.44 to 1.52), renal dysfunction (RR 1.10, 95% CI 0.79 to 1.54) or overall mortality (RR 0.81, 95% CI 0.63 to 1.06). Similar trends were seen with the lysine analogues, but data were sparse. These data conflict with the results of recently published non-randomised studies, which found increased risk of cardiovascular complications and death with aprotinin. There are concerns about the adequacy of reporting of uncommon events in the small clinical trials included in this review.When aprotinin was compared directly with either, or both, of the two lysine analogues it resulted in a significant increase in the risk of death (RR 1.39, 95% CI 1.02, 1.89), and a non-significant increase in the risk of myocardial infarction (RR 1.11 95% CI 0.82, 1.50). Most of the data contributing to this added risk came from a single study - the BART trial (2008).

AUTHORS' CONCLUSIONS

Anti-fibrinolytic drugs provide worthwhile reductions in blood loss and the receipt of allogeneic red cell transfusion. Aprotinin appears to be slightly more effective than the lysine analogues in reducing blood loss and the receipt of blood transfusion. However, head to head comparisons show a lower risk of death with lysine analogues when compared with aprotinin. The lysine analogues are effective in reducing blood loss during and after surgery, and appear to be free of serious adverse effects.

Anti-fibrinolytic use for minimising perioperative allogeneic blood transfusion

BACKGROUND

Concerns regarding the safety of transfused blood have led to the development of a range of interventions to minimise blood loss during major surgery. Anti-fibrinolytic drugs are widely used, particularly in cardiac surgery, and previous reviews have found them to be effective in reducing blood loss, the need for transfusion, and the need for re-operation due to continued or recurrent bleeding. In the last few years questions have been raised regarding the comparative performance of the drugs. The safety of the most popular agent, aprotinin, has been challenged, and it was withdrawn from world markets in May 2008 because of concerns that it increased the risk of cardiovascular complications and death.

OBJECTIVES

To assess the comparative effects of the anti-fibrinolytic drugs aprotinin, tranexamic acid (TXA), and epsilon aminocaproic acid (EACA) on blood loss during surgery, the need for red blood cell (RBC) transfusion, and adverse events, particularly vascular occlusion, renal dysfunction, and death.

SEARCH STRATEGY

We searched: the Cochrane Injuries Group's Specialised Register (July 2010), Cochrane Central Register of Controlled Trials (The Cochrane Library 2010, Issue 3), MEDLINE (Ovid SP) 1950 to July 2010, EMBASE (Ovid SP) 1980 to July 2010. References in identified trials and review articles were checked and trial authors were contacted to identify any additional studies. The searches were last updated in July 2010.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of anti-fibrinolytic drugs in adults scheduled for non-urgent surgery. Eligible trials compared anti-fibrinolytic drugs with placebo (or no treatment), or with each other.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data.

MAIN RESULTS

This review summarises data from 252 RCTs that recruited over 25,000 participants. Data from the head-to-head trials suggest an advantage of aprotinin over the lysine analogues TXA and EACA in terms of reducing perioperative blood loss, but the differences were small. Compared to control, aprotinin reduced the probability of requiring RBC transfusion by a relative 34% (relative risk [RR] 0.66, 95% confidence interval [CI] 0.60 to 0.72). The RR for RBC transfusion with TXA was 0.61 (95% CI 0.53 to 0.70) and was 0.81 (95% CI 0.67 to 0.99) with EACA. When the pooled estimates from the head-to-head trials of the two lysine analogues were combined and compared to aprotinin alone, aprotinin appeared more effective in reducing the need for RBC transfusion (RR 0.90; 95% CI 0.81 to 0.99).Aprotinin reduced the need for re-operation due to bleeding by a relative 54% (RR 0.46, 95% CI 0.34 to 0.62). This translates into an absolute risk reduction of 2% and a number needed-to-treat (NNT) of 50 (95% CI 33 to 100). A similar trend was seen with EACA (RR 0.32, 95% CI 0.11 to 0.99) but not TXA (RR 0.80, 95% CI 0.55 to 1.17). The blood transfusion data were heterogeneous and funnel plots indicate that trials of aprotinin and the lysine analogues may be subject to publication bias.When compared with no treatment aprotinin did not increase the risk of myocardial infarction (RR 0.87, 95% CI 0.69 to 1.11), stroke (RR 0.82, 95% CI 0.44 to 1.52), renal dysfunction (RR 1.10, 95% CI 0.79 to 1.54) or overall mortality (RR 0.81, 95% CI 0.63 to 1.06). Similar trends were seen with the lysine analogues, but data were sparse. These data conflict with the results of recently published non-randomised studies, which found increased risk of cardiovascular complications and death with aprotinin. There are concerns about the adequacy of reporting of uncommon events in the small clinical trials included in this review.When aprotinin was compared directly with either, or both, of the two lysine analogues it resulted in a significant increase in the risk of death (RR 1.39, 95% CI 1.02, 1.89), and a non-significant increase in the risk of myocardial infarction (RR 1.11 95% CI 0.82, 1.50). Most of the data contributing to this added risk came from a single study - the BART trial (2008).

AUTHORS' CONCLUSIONS

Anti-fibrinolytic drugs provide worthwhile reductions in blood loss and the receipt of allogeneic red cell transfusion. Aprotinin appears to be slightly more effective than the lysine analogues in reducing blood loss and the receipt of blood transfusion. However, head to head comparisons show a lower risk of death with lysine analogues when compared with aprotinin. The lysine analogues are effective in reducing blood loss during and after surgery, and appear to be free of serious adverse effects.

Effect of induced hypotensive anaesthesia vs isovolaemic haemodilution on blood loss and transfusion requirements in orthognathic surgery: a prospective, single-blinded, randomized, controlled clinical study

Induced hypotensive anaesthesia and isovolaemic haemodilution are well-established blood-sparing techniques in major surgery. This prospective study compared them for blood loss, transfusion requirements, and surgical field quality during standardized orthognathic operations. In a surgeon-blinded trial, 60 healthy patients requiring either Le Fort I osteotomy or bimaxillary surgery were randomly allocated to receive normotensive anaesthesia, induced hypotensive anaesthesia, or induced hypotensive anaesthesia combined with isovolaemic haemodilution. Blood loss and haemoglobin level were measured intraoperatively and calculated on postoperative day 3. The surgeons rated surgical field quality. Mean blood loss was 1021.63, 392.38 (p<0.05) and 1191.65ml in the normotensive, hypotensive and haemodilution groups, respectively. Mean haemoglobin level immediately after surgery was 9.3, 10.3, and 7.4g/dl (p<0.05), respectively. No hypotensive group patients received transfusions; four normotensive group patients required allogenic transfusions; seven haemodilution group patients needed autogenous retransfusions (p<0.05). Surgical field quality was significantly better in the hypotensive than in the normotensive (p<0.05) or haemodilution (p<0.05) groups. In orthognathic surgery, hypotensive anaesthesia significantly reduces blood loss and transfusion requirements and minimizes allogenic transfusions risks. Induced hypotensive anaesthesia combined with isovolaemic haemodilution has no additional blood-sparing effects but impairs surgical field quality.

Anti-fibrinolytic use for minimising perioperative allogeneic blood transfusion

BACKGROUND

Concerns regarding the safety of transfused blood have led to the development of a range of interventions to minimise blood loss during major surgery. Anti-fibrinolytic drugs are widely used, particularly in cardiac surgery and previous reviews have found them to be effective in reducing blood loss and the need for transfusion. Recently, questions have been raised regarding the comparative performance of the drugs and the safety of the most popular agent, aprotinin.

OBJECTIVES

To assess the comparative effects of the anti-fibrinolytic drugs aprotinin, tranexamic acid (TXA), and epsilon aminocaproic acid (EACA) on blood loss during surgery, the need for red blood (RBC) transfusion, and adverse events, particularly vascular occlusion, renal dysfunction, and death.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE, EMBASE, and the internet. References in identified trials and review articles were checked and trial authors were contacted to identify any additional studies. The searches were last updated in July 2006.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of anti-fibrinolytic drugs in adults scheduled for non-urgent surgery. Eligible trials compared anti-fibrinolytic drugs with placebo (or no treatment), or with each other.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data.

MAIN RESULTS

This review summarises data from 211 RCTs that recruited 20,781 participants. Data from placebo/inactive controlled trials, and from head-to-head trials suggest an advantage of aprotinin over the lysine analogues TXA and EACA in terms of operative blood loss, but the differences were small. Aprotinin reduced the probability of requiring RBC transfusion by a relative 34% (relative risk [RR] 0.66, 95% confidence interval [CI] 0.61 to 0.71). The RR for RBC transfusion with TXA was 0.61 (95% CI 0.54 to 0.69) and it was 0.75 (95% CI 0.58 to 0.96) with EACA. When the pooled estimates from the head-to-head trials of the two lysine analogues were combined and compared to aprotinin alone, aprotinin appeared superior in reducing the need for RBC transfusion: RR 0.83 (95% CI 0.69 to 0.99). Aprotinin reduced the need for re-operation due to bleeding: RR 0.48 (95% CI 0.35 to 0.68). This translates into an absolute risk reduction of just under 3% and a number needed-to-treat (NNT) of 37 (95% CI 27 to 56). Similar trends were seen with TXA and EACA, but the data were sparse and the differences failed to reach statistical significance. The blood transfusion data were heterogeneous and funnel plots indicate that trials of aprotinin and the lysine analogues may be subject to publication bias. Evidence of publication bias was not observed in trials reporting re-operation rates. Adjustment for these effects reduced the magnitude of estimated benefits but did not negate treatment effects. However, the apparent advantage of aprotinin over the lysine analogues was small and may be explained by publication bias and non-equivalent drug doses. Aprotinin did not increase the risk of myocardial infarction (RR 0.92, 95% CI 0.72 to 1.18), stroke (RR 0.76, 95% CI 0.35 to 1.64) renal dysfunction (RR 1.16, 95% CI 0.79 to 1.70) or overall mortality (RR 0.90, 95% CI 0.67 to 1.20). The analyses of myocardial infarction and death included data from the majority of subjects recruited into the clinical trials of aprotinin. However, under-reporting of renal events could explain the lack of effect seen with aprotinin. Similar trends were seen with the lysine analogues but data were sparse. These results conflict with the results of recently published non-randomised studies.

AUTHORS' CONCLUSIONS

Anti-fibrinolytic drugs provide worthwhile reductions in blood loss and the need for allogeneic red cell transfusion. Based on the results of randomised trials their efficacy does not appear to be offset by serious adverse effects. In most circumstances the lysine analogues are probably as effective as aprotinin and are cheaper; the evidence is stronger for tranexamic acid than for aminocaproic acid. In high risk cardiac surgery, where there is a substantial probability of serious blood loss, aprotinin may be preferred over tranexamic acid. Aprotinin does not appear to be associated with an increased risk of vascular occlusion and death, but the data do not exclude an increased risk of renal failure. There is no need for further placebo-controlled trials of aprotinin or lysine analogues in cardiac surgery. The principal need is for large comparative trials to assess the relative efficacy, safety and cost-effectiveness of anti-fibrinolytic drugs in different surgical procedures.

Hemoglobin Value Reduction and Necessity of Transfusion in Bimaxillary Orthognathic Surgery

PURPOSE

It has been the aim of the present clinical study to assess the reduction of the hemoglobin value and the frequency of blood transfusions during bimaxillary orthognathic surgery and to discuss the clinical consequences.

PATIENTS AND METHODS

Fifty-six patients (31 female, 25 male; mean age, 28.6 +/- 13.0 years; range, 14 to 66 years) were operated on. Twenty-nine patients predeposited blood before surgery. As a threshold for intraoperative or postoperative transfusion, a hemoglobin value of 7.5 g/100 mL was chosen.

RESULTS

Perioperatively, the hemoglobin values of the patients who predeposited blood decreased significantly after blood donation. The hemoglobin value reduced postoperatively by 2.6 +/- 1.4 g/100 mL in the non-donors and by 2.6 +/- 1.1 g/mL in the donors. None of the patients who did not predeposit blood received homologous blood transfusions intraoperatively or postoperatively. In the group of patients who predeposited blood, 3 were transfused intraoperatively. They received 1 or 2 units of autologous blood.

CONCLUSION

The individual statistics of the department show that there was only a limited reduction of the intraoperative and postoperative hemoglobin values as a consequence of bimaxillary orthognathic surgery. The increased safety of homologous blood and the minimal transfusion rates support abandonment of routine predepositing of autologous blood and the acceptance of homologous blood in the rare case of transfusion in bimaxillary surgery.

Evaluation of hemorrhage depressors on blood loss during orthognathic surgery: a retrospective study

PURPOSE

Correction of dentofacial deformities by orthognathic surgery may cause significant bleeding and therefore hypotensive anesthesia is often used to reduce the blood loss. The main objective of the present clinical study was to determine whether the addition of hemorrhage depressors to other medication during orthognathic surgery would further reduce the blood loss.

PATIENTS AND METHODS

Thirty patients, consecutively operated on with standardized Le Fort I osteotomies in 1998 (n = 15, control group) and 1999 (n = 15, treatment group), were included in the study. Both groups received hypotension anesthesia during surgery and the treatment group received additional hemorrhage depressors; tranexamic acid and desmopressin.

RESULTS

The mean blood loss was 740 +/- 410 mL (11.3 mL/kg) in the control group and 400 +/- 210 mL (5.7 mL/kg) in the treatment group. The results showed a statistically significant reduction of blood loss in the treatment group (P <.01).

CONCLUSIONS

This study shows that blood loss during orthognathic surgery under hypotensive anesthesia can be significantly reduced when a combination of tranexamic acid and desmopressin is added.

Blood transfusion requirements in bimaxillary osteotomies

The over-ordering of cross-matched blood to cover operations can result in blood shortages and is costly; it can never be free of risk. Current published guidelines recommend cross-matching 2 units of blood for bimaxillary orthognathic procedures with an additional 2 units if combined with a genioplasty. We reviewed the records of 115 consecutive cases of simultaneous bimaxillary osteotomies at Morriston Hospital over a 5-year period (January 1996 to December 2000). Ordering and use of blood were investigated and the cost analysed. Blood loss was minimised using a strategy of controlled moderate hypotension and meticulous haemostasis. Nine patients were given transfusions of blood but five of these were deemed inappropriate. No predisposing factors for transfusion were identified. We recommend that the tariff for ordering blood for bimaxillary osteotomies should be revised to a "group and save" with antibody screen, providing that a 30-min indirect antibody cross-match is available.

Anaesthetic management of coronary artery bypass grafting in a patient with central core disease and susceptibility to malignant hyperthermia on statin therapy

Central core disease and malignant hyperthermia (MH) are both associated with mutations in the RYR1 gene. We report the anaesthetic management of one such patient presenting for coronary artery bypass grafting. Her medication included aspirin 75 mg, atorvastatin 20 mg, isosorbide mononitrate 60 mg, atenolol 25 mg and glyceryl trinitrite sublingual spray as required. The use of aprotinin, statins and moderate hypothermia in patients with central core disease and known susceptibility to MH has not been documented.

Pharmacological strategies to decrease transfusion requirements in patients undergoing surgery

Surgical procedures are inevitably associated with bleeding. The amount of blood loss may vary widely between different surgical procedures and depends on surgical as well as non-surgical factors. Whereas adequate surgical haemostasis may suffice in most patients, pro-haemostatic pharmacological agents may be of additional benefit in patients with (diffuse) surgical bleeding or in patients with a specific underlying haemostatic defect. In general, surgical haemostasis and pharmacological therapies can be complementary in controlling blood loss. The use of pharmacological therapies to reduce blood loss and blood transfusions in surgery has historically been restricted to a few drugs. Antifibrinolytic agents (aprotinin, tranexamic acid and aminocaproic acid) have the best evidence supporting their use, especially in cardiac surgery, liver transplantation and some orthopaedic surgical procedures. Meta-analyses of randomised, controlled trials in cardiac patients have suggested a slight benefit of aprotinin, compared with the other antifibrinolytics. Desmopressin is the treatment of choice in patients with mild haemophilia A and von Willebrand disease. It has also been shown to be effective in patients undergoing cardiac surgery who received aspirin up to the time of operation. However, overall evidence does not support a beneficial effect of desmopressin in patients without pre-existing coagulopathy undergoing elective surgical procedures. Topical agents, such as fibrin sealants have been successfully used in a variety of surgical procedures. However, only very few controlled clinical trials have been performed and scientific evidence supporting their use is still limited. Novel drugs, like recombinant factor VIIa (eptacog alfa), are currently under clinical investigation. Recombinant factor VIIa has been introduced for the treatment of haemophilia patients with inhibitors, either in surgical or non-surgical situations. Preliminary data indicate that it may also be effective in surgical patients without pre-existing coagulation abnormalities. More clinical trials are warranted before definitive conclusions can be drawn about the safety and the exact role of this new drug in surgical patients. Only adequately powered and properly designed randomised, clinical trials will allow us to define the most effective and the safest pharmacological therapies for reducing blood loss and transfusion requirements in surgical patients. Future trials should also consider cost-effectiveness because of considerable differences in the costs of the available pro-haemostatic pharmacological agents.