The hemostatic effects of desmopressin on patients who had total joint arthroplasty. A double-blind randomized trial

Desmopressin use for minimising perioperative blood transfusion

BACKGROUND

Blood transfusion is administered during many types of surgery, but its efficacy and safety are increasingly questioned. Evaluation of the efficacy of agents, such as desmopressin (DDAVP; 1-deamino-8-D-arginine-vasopressin), that may reduce perioperative blood loss is needed.

OBJECTIVES

To examine the evidence for the efficacy of DDAVP in reducing perioperative blood loss and the need for red cell transfusion in people who do not have inherited bleeding disorders.

SEARCH METHODS

We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (2017, issue 3) in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (from 1937), the Transfusion Evidence Library (from 1980), and ongoing trial databases (all searches to 3 April 2017).

SELECTION CRITERIA

We included randomised controlled trials comparing DDAVP to placebo or an active comparator (e.g. tranexamic acid, aprotinin) before, during, or immediately after surgery or after invasive procedures in adults or children.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We identified 65 completed trials (3874 participants) and four ongoing trials. Of the 65 completed trials, 39 focused on adult cardiac surgery, three on paediatric cardiac surgery, 12 on orthopaedic surgery, two on plastic surgery, and two on vascular surgery; seven studies were conducted in surgery for other conditions. These trials were conducted between 1986 and 2016, and 11 were funded by pharmaceutical companies or by a party with a commercial interest in the outcome of the trial.The GRADE quality of evidence was very low to moderate across all outcomes. No trial reported quality of life. DDAVP versus placebo or no treatmentTrial results showed considerable heterogeneity between surgical settings for total volume of red cells transfused (low-quality evidence) and for total blood loss (very low-quality evidence) due to large differences in baseline blood loss. Consequently, these outcomes were not pooled and were reported in subgroups.Compared with placebo, DDAVP may slightly decrease the total volume of red cells transfused in adult cardiac surgery (mean difference (MD) -0.52 units, 95% confidence interval (CI) -0.96 to -0.08 units; 14 trials, 957 participants), but may lead to little or no difference in orthopaedic surgery (MD -0.02, 95% CI -0.67 to 0.64 units; 6 trials, 303 participants), vascular surgery (MD 0.06, 95% CI -0.60 to 0.73 units; 2 trials, 135 participants), or hepatic surgery (MD -0.47, 95% CI -1.27 to 0.33 units; 1 trial, 59 participants).DDAVP probably leads to little or no difference in the total number of participants transfused with blood (risk ratio (RR) 0.96, 95% CI 0.86 to 1.06; 25 trials; 1806 participants) (moderate-quality evidence).Whether DDAVP decreases total blood loss in adult cardiac surgery (MD -135.24 mL, 95% CI -210.80 mL to -59.68 mL; 22 trials, 1358 participants), orthopaedic surgery (MD -285.76 mL, 95% CI -514.99 mL to -56.53 mL; 5 trials, 241 participants), or vascular surgery (MD -582.00 mL, 95% CI -1264.07 mL to 100.07 mL; 1 trial, 44 participants) is uncertain because the quality of evidence is very low.DDAVP probably leads to little or no difference in all-cause mortality (Peto odds ratio (pOR) 1.09, 95% CI 0.51 to 2.34; 22 trials, 1631 participants) or in thrombotic events (pOR 1.36, 95% CI, 0.85 to 2.16; 29 trials, 1984 participants) (both low-quality evidence). DDAVP versus placebo or no treatment for people with platelet dysfunctionCompared with placebo, DDAVP may lead to a reduction in the total volume of red cells transfused (MD -0.65 units, 95% CI -1.16 to -0.13 units; 6 trials, 388 participants) (low-quality evidence) and in total blood loss (MD -253.93 mL, 95% CI -408.01 mL to -99.85 mL; 7 trials, 422 participants) (low-quality evidence).DDAVP probably leads to little or no difference in the total number of participants receiving a red cell transfusion (RR 0.83, 95% CI 0.66 to 1.04; 5 trials, 258 participants) (moderate-quality evidence).Whether DDAVP leads to a difference in all-cause mortality (pOR 0.72, 95% CI 0.12 to 4.22; 7 trials; 422 participants) or in thrombotic events (pOR 1.58, 95% CI 0.60 to 4.17; 7 trials, 422 participants) is uncertain because the quality of evidence is very low. DDAVP versus tranexamic acidCompared with tranexamic acid, DDAVP may increase the volume of blood transfused (MD 0.6 units, 95% CI 0.09 to 1.11 units; 1 trial, 40 participants) and total blood loss (MD 142.81 mL, 95% CI 79.78 mL to 205.84 mL; 2 trials, 115 participants) (both low-quality evidence).Whether DDAVP increases or decreases the total number of participants transfused with blood is uncertain because the quality of evidence is very low (RR 2.42, 95% CI 1.04 to 5.64; 3 trials, 135 participants).No trial reported all-cause mortality.Whether DDAVP leads to a difference in thrombotic events is uncertain because the quality of evidence is very low (pOR 2.92, 95% CI 0.32 to 26.83; 2 trials, 115 participants). DDAVP versus aprotininCompared with aprotinin, DDAVP probably increases the total number of participants transfused with blood (RR 2.41, 95% CI 1.45 to 4.02; 1 trial, 99 participants) (moderate-quality evidence).No trials reported volume of blood transfused or total blood loss and the single trial that included mortality as an outcome reported no deaths.Whether DDAVP leads to a difference in thrombotic events is uncertain because the quality of evidence is very low (pOR 0.98, 95% CI 0.06 to 15.89; 2 trials, 152 participants).

AUTHORS' CONCLUSIONS

Most of the evidence derived by comparing DDAVP versus placebo was obtained in cardiac surgery, where DDAVP was administered after cardiopulmonary bypass. In adults undergoing cardiac surgery, the reduction in volume of red cells transfused and total blood loss was small and was unlikely to be clinically important. It is less clear whether DDAVP may be of benefit for children and for those undergoing non-cardiac surgery. A key area for researchers is examining the effects of DDAVP for people with platelet dysfunction. Few trials have compared DDAVP versus tranexamic acid or aprotinin; consequently, we are uncertain of the relative efficacy of these interventions.

Does a single loading dose of tranexamic acid reduce perioperative blood loss and transfusion requirements after total knee replacement surgery? A randomized, controlled trial

Background:

Total knee replacement (TKR) is associated with high-perioperative blood loss, which often requires allogenic blood transfusion. Among the many strategies to decrease the need for allogenic transfusion, tranexamic acid (TA) is used systemically in perioperative setting with promising outcome. Here we evaluated the efficacy of single preoperative bolus dose of TA on reduction in blood loss and red blood cell transfusion in patients undergoing unilateral TKR.

Materials and Methods:

70, American Society of Anesthesiologists I-II patients scheduled for unilateral TKR were included. Patients were randomly allocated into two groups to receive either TA (Group-TA; 20 mg/kg diluted to 25 cc with normal saline) or an equivalent volume of normal saline (Group P). Hemoglobin concentration, packed cell volume, platelet count, fibrinogen level, D-dimer level was measured preoperatively and at 6^th and 24^th h postoperative period.

Results:

In Group P more blood, colloid and crystalloid solutions were used to replace the blood loss. 27 patients in Group TA did not require transfusion of any blood products compared to 6 patients in Group P (P < 0.0001) and only 3 units of blood was transfused in Group TA where as a total of 32 units of blood was transfused in Group P. Despite the more numerous transfusions, Hb% after 6 h and 24 h in Group P were considerably low in comparison with Group TA (P < 0.0001).

Conclusion:

Tranexamic acid while significantly reducing blood loss caused by TKR surgery collaterally reduced the need for postoperative blood transfusion.

Practice guidelines for perioperative blood management: an updated report by the American Society of Anesthesiologists Task Force on Perioperative Blood Management*

The American Society of Anesthesiologists Committee on Standards and Practice Parameters and the Task Force on Perioperative Blood Management presents an updated report of the Practice Guidelines for Perioperative Blood Management.

Supplemental Digital Content is available in the text.

Use of tranexamic acid is a cost effective method in preventing blood loss during and after total knee replacement

Background & Purpose

Allogenic blood transfusion in elective orthopaedic surgery is best avoided owing to its associated risks. Total knee replacement often requires blood transfusion, more so when bilateral surgery is performed. Many strategies are currently being employed to reduce the amount of peri-operative allogenic transfusions. Anti-fibrinolytic compounds such as aminocaproic acid and tranexamic acid have been used systemically in perioperative settings with promising results. This study aimed to evaluate the effectiveness of tranexamic acid in reducing allogenic blood transfusion in total knee replacement surgery.

Methodology

This was a retrospective cohort study conducted on patients undergoing total knee replacement during the time period November 2005 to November 2008. Study population was 99 patients, of which 70 underwent unilateral and 29 bilateral knee replacement. Forty-seven patients with 62 (49.5%) knees (group-I) had received tranexamic acid (by surgeon preference) while the remaining fifty-two patients with 66 (51.5%) knees (group-II) had did not received any tranexamic acid either pre- or post-operatively.

Results

The mean drop in the post-operative haemoglobin concentration in Group-II for unilateral and bilateral cases was 1.79 gm/dl and 2.21 gm/dl, with a mean post-operative drainage of 1828 ml (unilateral) and 2695 ml (bilateral). In comparison, the mean drop in the post-op haemoglobin in Group-I was 1.49 gm/dl (unilateral) and 1.94 gm/dl (bilateral), with a mean drainage of 826 ml (unilateral) and 1288 ml (bilateral) (p-value < 0.001).

Interpretation

Tranexamic acid is effective in reducing post-operative drainage and requirement of blood transfusion after knee replacement.

Perioperative blood transfusion: the role of allogenous and autologous transfusions, and pharmacological agents

The decision to transfuse patients perioperatively is made on an individual basis and should consider factors such as duration and severity of anaemia, symptoms, physiological parameters and comorbidities. Autologous blood transfusion has the benefit of avoiding some of the immunological and infective complications associated with allogenic blood transfusion. Pharmacological agents as well as anaesthetic and surgical techniques have a role in avoiding the need for blood transfusion.

The effect of desmopressin on blood loss in patients with rheumatoid arthritis undergoing hip arthroplasty

BACKGROUND

Blood loss is an important issue for patients with rheumatoid arthritis undergoing hip surgery. We hypothesised that intraoperative desmopressin treatment would result in a reduction in blood loss in rheumatoid patients undergoing total hip arthroplasty.

METHODS

Seventy-five patients scheduled for elective total hip arthroplasty were randomised to three groups to receive 0.4 microg/kg desmopressin (D 0.4), 0.2 microg/kg desmopressin (D 0.2) or placebo intraoperatively in a double-blind fashion. Blood transfusions were based on calculated safe allowable blood loss and haemoglobin measurements (trigger 90 g/l, 5.59 mmol/l). The primary endpoint was the total blood loss measured till the end of the fourth post-operative day. Secondary endpoints included red cell transfusion requirements and haemoglobin.

RESULTS

Total blood loss during the study period was not significantly different between the groups (D 0.4 1829 +/- 1068; D 0.2 2240 +/- 843 and placebo 2254 +/- 1040 ml; P= 0.50). The total amount of red cell transfusions was fewer in group D 0.4 (3.6 +/- 1.6 U) when compared with D 0.2 (4.4 +/- 1.7 U; P=0.009) and placebo (4.5 +/- 2.0 U; P= 0.011) groups. Haemoglobin concentration was lower in the placebo group in the first (5.42 +/- 1.16 vs. 5.98 +/- 0.47 mmol/l; P=0.033) and the second (6.28 +/- 0.66 vs. 6.69 +/- 0.47 mmol/l; P=0.033) post-operative mornings compared with group D 0.4.

CONCLUSION

Despite a lack of difference in the primary outcome, total blood loss, intraoperative administration of 0.4 microg/kg desmopressin resulted in fewer total red cell transfusion requirements in rheumatoid patients undergoing total hip arthroplasty when compared with 0.2 microg/kg treatment and placebo.

Strategies for blood management in orthopaedic and trauma surgery

Several aspects of the management of an orthopaedic surgical patient are not directly related to the surgical technique but are nevertheless essential for a successful outcome. Blood management is one of these. This paper considers the various strategies available for the management of blood loss in patients undergoing orthopaedic and trauma surgery.

A benefit-risk review of systemic haemostatic agents: part 1: in major surgery

Systemic haemostatic agents play an important role in the management of blood loss during major surgery where significant blood loss is likely and their use has increased in recent times as a consequence of demand for blood products outstripping supply and the risks associated with transfusions. Their main application is as prophylaxis to reduce bleeding in major surgery, including cardiac and orthopaedic surgery and orthotopic liver transplantation. Aprotinin has been the predominant agent used in this setting; of the other antifibrinolytic agents that have been studied, tranexamic acid is the most effective and epsilon-aminocaproic acid may also have a role. Eptacog alfa (recombinant factor VIIa) has also shown promise. Tranexamic acid, epsilon-aminocaproic acid and eptacog alfa are generally well tolerated; however, when considering the methods to reduce or prevent blood loss intra- and postoperatively, the benefits of these agents need to be weighed against the risk of adverse events. Recently, concerns have been raised about the safety of aprotinin after an association between increased renal dysfunction and mortality was shown in retrospective observational studies and an increase in all-cause mortality with aprotinin relative to tranexamic acid or epsilon-aminocaproic acid was seen after a pre-planned periodic analysis of the large BART (Blood conservation using Antifibrinolytics in a Randomized Trial) study. The latter finding resulted in the trial being halted, and aprotinin has subsequently been withdrawn from the market pending detailed analysis of efficacy and safety results from the study. Part 1 of this benefit-risk review examines the efficacy and adverse effect profiles of systemic haemostatic agents commonly used in surgery, and provides individual benefit-risk profiles that may assist clinicians in selecting appropriate pharmacological therapy in this setting.

The use of desmopressin in open-heart surgery

Desmopressin (l-deamino-8-D-arginine vasopressin, DDAVP) is a synthetic analogue of the antidiuretic hormone vasopressin. Like the natural antidiuretic hormone, desmopressin increases the plasma levels of factor VIII and von Willebrand factor (vWF), with the advantage, compared to vasopressin, that it produces little or no vasoconstriction, no increase in blood pressure, and no contraction of the uterus or gastrointestinal tract, so that it is well tolerated when administered to humans. In 1977, desmopressin was used for the first time in patients with mild hemophilia A and von Willebrand disease (vWD) for the prevention and treatment of bleeding, first during dental extractions and then during major surgical procedures. The clinical indications for desmopressin rapidly expanded beyond hemophilia and vWD. The compound was shown to be efficacious even in bleeding disorders not involving a deficiency or dysfunction of factor VIII or vWF, including congenital and acquired defects of platelet function and such frequent abnormalities of hemostasis as those associated with chronic kidney and liver diseases. Desmopressin has also been used prophylactically in patients undergoing surgical operations characterized by large blood loss and transfusion requirements.

The use of desmopressin as a hemostatic agent: a concise review

Desmopressin, a synthetic derivative of the antidiuretic hormone vasopressin, is the treatment of choice for most patients with von Willebrand disease and mild hemophilia A. Moreover, the compound has been shown to be useful in a variety of inherited and acquired hemorrhagic conditions, including some congenital platelet function defects, chronic liver disease, uremia, and hemostatic defects induced by the therapeutic use of antithrombotic drugs such as aspirin and ticlopidine. Finally, desmopressin has been used as a blood saving agent in patients undergoing operations characterized by large blood loss and transfusion requirements, but studies suggest that this is not as effective as other methods. This review briefly summarizes the current clinical indications on the use of desmopressin as a hemostatic agent.

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.

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.

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.

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.

Desmopressin does not decrease blood loss and transfusion requirements in patients undergoing hepatectomy

PURPOSE

To determine the effects of desmopressin on coagulation and blood loss in patients undergoing elective partial hepatectomy.

METHODS

A randomized, controlled and double-blind study on 59 patients who received either 0.3 micro g x kg(-1) of desmopressin or an equal volume of normal saline (control) infused intravenously over 20 min after induction of general anesthesia.

RESULTS

There was an increase in plasma levels of factors VIII and von Willebrand after the infusion of study drug in both groups (P < 0.001). The activated partial thromboplastin time was shortened in Group D whereas prothrombin time was prolonged in Group C; (P = 0.02). A large range of intraoperative blood loss (400-7128 mL) was observed, with no significant differences between groups. There were no changes in plasma electrolyte levels or osmolality. Transfusion requirements were similar in both groups.

CONCLUSION

Desmopressin did not reduce intraoperative blood loss or transfusion requirements during hepatectomy despite raising clotting factor levels and improving tests of hemostasis.

Perioperative blood management practices in elective orthopaedic surgery

Concern about the cost and safety of allogenic blood transfusion, including the risk of viral infection and immunosuppression, has led to refinements in and new approaches to blood conservation, including the development of transfusion practice standards and improvements in surgical practice. Preoperative autologous blood collection, the use of hemostatic agents, perioperative blood salvage, and the use of recombinant human erythropoietin (epoetin alfa) to stimulate erythropoiesis have contributed to decreased use of allogenic blood services. Development of appropriate blood management strategies to help reduce or eliminate exposure to allogenic blood requires a preoperative assessment of the likelihood of transfusion and of the risks as well as costs associated with conservation and replacement options. The informed selection of alternatives based on preoperative assessment of hematologic status, estimated blood loss, and sources for blood replacement may enhance blood management practices in major elective orthopaedic surgery.

Safety and efficacy of methods for reducing perioperative allogeneic transfusion: a critical review of the literature

A number of pharmacologic and nonpharmacologic technologies are in current use to minimize perioperative homologous blood use. Clinical trials, many of them randomized controlled trials, have been done evaluating these approaches and have demonstrated their efficacy. However, data on safety has relied mostly on case reports, uncontrolled studies, and, for the pharmacologic agents, extrapolation from the nonsurgical setting. In this review I analyze the data from the randomized trials and the lower-level evidence studies to provide the best estimates in safety with these alternatives. In general, these alternatives are safe with proper dosing and monitoring of effects. With aprotinin, the primary concern is anaphylaxis, and this predominantly with re-exposure. With aprotinin and with the anti-fibrinolytics, increased venous thromboembolic risk has not been a consistent finding. Tranexamic acid use intraoperatively is advantageous, but postoperative use appears to have no advantage and may be associated with renal dysfunction. DDAVP is low-risk, provided it is not overused, which can induce hyponatremia. Autologous predonation probably has similar risks as homologous blood with respect to transfusion errors and bacterial infection. As with most medical interventions, we must be vigilant to prevent human error.

The effect of tourniquet application, tranexamic acid, and desmopressin on the procoagulant and fibrinolytic systems during total knee replacement

STUDY OBJECTIVE

To assess the influence of tourniquet inflation-deflation as well as desmopressin and tranexamic acid (TA) administration on prothrombin fragment 1.2, fibrinogen, plasmin antiplasmin complex, and D-dimer concentrations during total knee replacement.

DESIGN

Randomized, placebo-controlled study.

SETTING

Large referral hospital.

PATIENTS

30 ASA physical status I, II, and III patients undergoing total knee replacement.

INTERVENTIONS

Patients were randomized to one of three treatment groups. Patients received either tranexamic acid, desmopressin, or an equal volume of saline, intravenously.

MEASUREMENTS AND MAIN RESULTS

Cubital blood was drawn immediately before induction of anesthesia, 1 hour after tourniquet application, and 2 and 15 minutes after tourniquet deflation. Fibrinogen and D-dimer levels were measured using the Clauss Method and latex agglutination, respectively. Plasmin antiplasmin complex and prothrombin fragment 1.2 levels were measured by enzyme-linked immunosorbent assay (ELISA). All assays were performed in duplicate, and intra-assay variability was documented. No statistically significant difference in fibrinogen, D-dimer, plasmin antiplasmin complex, or prothrombin fragment 1.2 levels was demonstrated among the groups. Similarly, within each group there were no statistically significant differences in the variables studied. However, despite the lack of statistical significance, when compared with their levels during tourniquet application, an increase in D-dimer and plasmin antiplasmin complex levels was observed in all three groups at 2 and 15 minutes after tourniquet release. In contrast, no increase in prothrombin fragment 1.2 generation was noted. Significantly more allogeneic blood was transfused in the Control and Desmopressin Groups when compared with the tranexamic acid group (p< 0.02).

CONCLUSIONS

No evidence of tourniquet-induced fibrinolysis or thrombin generation was demonstrated in the systemic circulation. Desmopressin and tranexamic acid had no significant effect on the variables measured.

A comparative study of the postoperative allogeneic blood-sparing effects of tranexamic acid and of desmopressin after total knee replacement

BACKGROUND

Tissue hypoxia and reperfusion induce abnormal hemostatic function. Therefore, bleeding after total knee replacement (TKR) may be a result of a tourniquet-induced imbalance of the procoagulant and fibrinolytic systems. Because laboratory confirmation of tourniquet-induced abnormal hemostasis is difficult to obtain, indirect evidence must be sought.

STUDY DESIGN AND METHODS

A prospective, single-blind study of 40 patients undergoing TKR was performed. In the tranexamic acid (TA) group, in the 30 minutes before the limb tourniquet was deflated, an IV bolus dose of TA (15 mg/kg) was administered. Thereafter, a constant IV infusion of 10 mg per kg per hour was administered until 12 hours after tourniquet deflation. In the desmopressin group, desmopressin (0.3 mg/kg) and saline were administered by a similar protocol. No blood was administered intraoperatively. A postoperative Hct <27 percent constituted the postoperative transfusion trigger. Patients were examined daily for signs of lower-limb deep vein thrombosis, and they underwent lower-limb Doppler ultrasound on postoperative Day 5. Three months after surgery, the incidence of delayed thromboembolic events was assessed.

RESULTS

During the first 12 postoperative hours, blood accumulation in the surgical drain was significantly (p<0.05) lower in the TA group (162 mL +/- 129) than in the desmopressin group (342 mL +/- 169). From the sixth postoperative hour until 3 days postoperatively, Hct levels were significantly lower in the desmopressin group than in the TA group. Significantly more allogeneic blood was transfused in the desmopressin group (11 patients received 16 units) than in the TA group (3 patients each received 1 unit) (p<0.02). There were no clinical signs of deep vein thrombosis or abnormal Doppler ultrasound studies. Three months postoperatively, there were no thromboembolic events among the 37 patients interviewed.

CONCLUSION

TA induces better blood sparing than desmopressin. Therefore, a tourniquet-induced increase in fibrinolysis is the likely cause of delayed bleeding after TKR surgery. However, before routine administration, the effect of TA on the incidence of thromboembolic events requires further investigation.

Systemic hemostatic medications for reducing surgical blood loss

OBJECTIVE

To review randomized trials involving the use of systemic hemostatic medications for reducing surgical blood loss.

DATA SOURCES

Articles were obtained through searches of MEDLINE (1966-September 2000). The bibliographies of retrieved publications were reviewed for additional references.

STUDY SELECTION

All randomized studies and pharmacoeconomic evaluations that involved medications used for systemic hemostasis in the perioperative period were included.

DATA EXTRACTION

Randomized studies involving conjugated estrogens, aminocaproic acid, tranexamic acid, desmopressin, and aprotinin for systemic hemostasis were extracted. Studies of proton-pump inhibitors for upper gastrointestinal bleeding and octreotide for variceal bleeding were excluded, as were trials involving the use of any hemostatic agent for cardiovascular surgery. The primary outcome under review was a reduction in bleeding as defined by reduced transfusion requirements.

DATA SYNTHESIS

There is limited efficacy and toxicity information concerning the use of conjugated estrogens for reducing surgery-related bleeding. Similarly, there are a limited number of randomized studies involving aminocaproic acid and tranexamic acid, and with the exception of tranexamic acid for reducing transfusion requirements with knee surgery, the study results are either conflicting or negative. For desmopressin, evidence from a substantial number of randomized trials documents its lack of efficacy. Aprotinin has reduced bleeding and transfusion requirements in a number of randomized studies involving patients undergoing orthopedic surgery, but cost-effectiveness studies are needed to better define its therapeutic role. Trials of aprotinin during hepatic surgery have yielded conflicting results.

CONCLUSIONS

Most hemostatic medications used for reducing surgery-related bleeding have limited or contradictory evidence of efficacy.

Effects of deamino-8-D-arginin vasopressin on blood loss and coagulation factors in scoliosis surgery. A double-blind randomized clinical trial

STUDY DESIGN

A double-blind, randomized, prospective clinical study was performed to evaluate the efficacy of deamino-8-D-arginin vasopressin in reducing blood loss in major scoliosis surgery.

OBJECTIVES

To evaluate whether desmopressin has any effect on reducing blood loss in spinal surgery, to identify the probable mechanisms of effectiveness via blood coagulation factors, and to outline any adverse effect associated with the use of deamino-8-D-arginin vasopressin.

SUMMARY OF BACKGROUND DATA

Scoliosis surgery is known to be associated with major blood loss. Because of major drawbacks of homologous blood transfusion, many alternative methods have been used to counter the blood loss. Only a few studies exist, with controversial results, on the use of deamino-8-D-arginin vasopressin.

METHODS

The study population included 40 operations on 35 consecutive patients undergoing reconstructive surgery for either idiopathic (n = 26) or congenital (n = 9) scoliosis. Operations were randomized into deamino-8-D-arginin vasopressin (0.3 microgram/kg body weight; maximum, 20 micrograms) (n = 18) or placebo (n = 22) groups and stratified according to the diagnosis and the type of surgery performed (i.e., anterior versus posterior versus anterior and posterior sequential). Parameters of blood loss, serum levels of blood coagulation factors at different time intervals, and urinary output were measured.

RESULTS

Findings indicated that blood loss per kilogram of body weight, blood loss per surgically treated spinal level, urinary output per kilogram of body weight and serum levels of fibrinogen, von Willebrand factor (vWF) activity, tissue type plasminogen activator activity, and plasminogen activator inhibitor activity were not sensitive to the administration of deamino-8-D-arginin vasopressin at any time interval during surgery or at 24 hours after surgery (P > 0.05). Only factor VIII:C levels exhibited significant elevations at 30 minutes and at 24 hours (P < 0.05).

CONCLUSIONS

This study could not demonstrate any significant effect of deamino-8-D-arginin vasopressin on the amount of blood loss in a group of patients with idiopathic or congenital scoliosis. Findings indicate that for most of the coagulation factors, any changes in serum levels induced by deamino-8-D-arginin vasopressin were much like those expected from surgery itself. This study also failed to demonstrate any significant effects altering the urinary output that may be attributed to the use of deamino-8-D-arginin vasopressin.

Transfusion-free surgery is a treatment plan for all patients

Due to the increased risks associated with allogenic blood transfusion, blood management in surgical procedures, especially in orthopedic settings, should include reduction of perioperative blood loss. Preoperative nursing assessment will help define patients at increased risk for transfusion. Both nonpharmacologic and pharmacologic techniques can help minimize allogenic transfusion by reducing blood loss. One such method of managing anemia and reducing patient exposure to allogenic transfusion is the perioperative use of recombinant human erythropoietin--erythropoietin alfa--an innovative surgical blood management tool. Increased awareness by perioperative nurses of the use of erythropoietin alfa and patient implications can contribute to the overall blood conservation goal.

Tranexamic acid radically decreases blood loss and transfusions associated with total knee arthroplasty

The application of a pneumatic tourniquet in orthopedic procedures enhances local fibrinolysis. Consequently, a short-term antifibrinolytic therapy may be indicated in this clinical situation to reduce postoperative blood loss. The purpose of this prospective double-blind study was to investigate the effect of tranexamic acid (TA) on blood loss associated with total knee arthroplasty (TKA). Seventy-five patients scheduled for 77 TKAs were randomized to receive either TA (n = 39) or equal volume of normal saline (NS, n = 38). Before deflation of the tourniquet, 15 mg/kg of TA was given intravenously followed by two 10-mg/kg additional doses. Perioperative blood loss gathered in surgical gauzes, suction reservoirs, and postoperative drainage system was measured. The number of transfusions given during hospitalization was registered. Total blood loss (mean +/- SD) was 689 +/- 289 mL in the TA group and 1509 +/- 643 mL in the NS group (P < 0.0001). The mean number of transfused red cell units in the TA group was 1.0 +/- 1.2 compared to 3.1 +/- 1.6 in the NS group (P < 0.0001). Twenty-two patients in the TA group and four patients in the NS group were treated without transfusion (P < 0.00003). Two patients in the TA group and three in the NS group had a deep venous thrombosis, including a fatal case of pulmonary embolism in the NS group. We conclude that short-term TA therapy significantly reduces TKA-associated blood loss and transfusion requirements without increasing thromboembolic complications.

Ten strategies to reduce blood loss in orthopedic surgery

In any operative procedure, careful surgical dissection with precise hemostasis is one of the most effective ways to minimize surgical blood loss and reduce the need for allogeneic red blood cell transfusion. Several other techniques contribute to reduce blood loss in major orthopedic procedures. These techniques are reviewed and include rehearsal of the procedure and positioning the patient to reduce venous engorgement. In addition, a case report is presented that demonstrates the feasibility of revision hip replacement surgery without the use of transfusion in a Jehovah's Witness patient.

Does desmopressin improve hemostasis and reduce blood loss from aortic surgery? A randomized, double-blind study

PURPOSE

The purpose of this study was to determine the effect of desmopressin acetate (DDAVP) on blood loss, transfusion requirements, and thromboembolic complications in patients undergoing elective aortic operations.

METHODS

A randomized, double-blind trial was carried out during a 3-year period with patients receiving 20 micrograms DDAVP or identical-appearing placebo at the time of aortic cross-clamp placement. In addition to major bleeding and thromboembolic end points, bleeding times and platelet counts were monitored serially.

RESULTS

Forty-three patients were randomized to receive DDAVP, and 48 were assigned to a placebo. An equivalent proportion of patients with aneurysm and patients with occlusive disease was in each group. In spite of mild prolongation in the postoperative bleeding times and moderate thrombocytopenia, DDAVP had no beneficial effect on blood loss or transfusion requirements. Total blood transfusion amount (mean +/- standard deviation) for patients receiving DDAVP was 3.1 +/- 3.0 U compared with 2.7 +/- 3.0 U for those receiving placebo. For all patients the period associated with the greatest blood loss was the time between heparin administration with cross-clamp application and reversal of heparin with protamine sulfate. The incidence of major thromboembolic complications was similar in both groups.

CONCLUSION

Thrombocytopenia and mild platelet dysfunction are common after aortic operation, but DDAVP does not improve hemostasis or lessen transfusion requirements. This study does not rule out a beneficial effect of DDAVP in patients who are undergoing more complex aortic operations or who have major hemostatic aberrations.