The influence of desmopressin on blood loss during spinal fusion surgery in neuromuscular patients

Desmopressin to reduce periprocedural bleeding and transfusion: a systematic review and meta-analysis

We systematically reviewed the literature to investigate the effects of peri-procedural desmopressin in patients without known inherited bleeding disorders undergoing surgery or other invasive procedures. We included 63 randomized trials (4163 participants) published up to February 1, 2023. Seven trials were published after a 2017 Cochrane systematic review on this topic. There were 38 trials in cardiac surgery, 22 in noncardiac surgery, and 3 in non-surgical procedures. Meta-analyses demonstrated that desmopressin likely does not reduce the risk of receiving a red blood cell transfusion (25 trials, risk ratio [RR] 0.95, 95% confidence interval [CI] 0.86 to 1.05) and may not reduce the risk of reoperation due to bleeding (22 trials, RR 0.75, 95% CI 0.47 to 1.19) when compared to placebo or usual care. However, we demonstrated significant reductions in number of units of red blood cells transfused (25 trials, mean difference -0.55 units, 95% CI - 0.94 to - 0.15), total volume of blood loss (33 trials, standardized mean difference - 0.40 standard deviations; 95% CI - 0.56 to - 0.23), and the risk of bleeding events (2 trials, RR 0.45, 95% CI 0.24 to 0.84). The certainty of evidence of these findings was generally low. Desmopressin increased the risk of clinically significant hypotension that required intervention (19 trials, RR 2.15, 95% CI 1.36 to 3.41). Limited evidence suggests that tranexamic acid is more effective than desmopressin in reducing transfusion risk (3 trials, RR 2.38 favoring tranexamic acid, 95% CI 1.06 to 5.39) and total volume of blood loss (3 trials, mean difference 391.7 mL favoring tranexamic acid, 95% CI - 93.3 to 876.7 mL). No trials directly informed the safety and hemostatic efficacy of desmopressin in advanced kidney disease. In conclusion, desmopressin likely reduces periprocedural blood loss and the number of units of blood transfused in small trials with methodologic limitations. However, the risk of hypotension needs to be mitigated. Large trials should evaluate desmopressin alongside tranexamic acid and enroll patients with advanced kidney disease.

Correction of adult spinal deformity with a minimally invasive fusionless bipolar construct: Preliminary results

INTRODUCTION

Fusion in adult spinal deformity has a high rate of complications. Fusionless constructs in children and percutaneous fixation in adults are now being used routinely. The aim of this study was to evaluate the preliminary results of a minimally invasive fusionless surgical technique used to correct adult spinal deformity.

MATERIALS AND METHODS

Thirty-eight patients with an average age of 45 years (15-76) with major spinal deformity requiring extensive arthrodesis from the upper thoracic region to the pelvis were operated consecutively and followed prospectively. Two hooks were implanted at the top and two iliosacral screws at the bottom. Two large rods connected by dominos to two small rods joined the upper hooks to the lower screws. The surgical data (operative time and bleeding), the radiological findings (Cobb angle, sagittal parameters, C7-plumbline AP and lateral), the complication rate and the morbidity were evaluated at the last follow-up visit.

RESULTS

The primary curvature was reduced by 40% from a mean of 58.5° (26-146) to 35.2° (3-109) (p<0.001). A clear decrease in operating time (270min) and blood loss (50cc/level) were observed. The length of hospitalization averaged 18 days (6-66), including an 8-15 day long preoperative traction period for 11 patients. We found 7 infectious complications, 11 early mechanical complications and one case of paraplegia due to severe kyphoscoliosis.

CONCLUSION

The corrections obtained are comparable to those reported in the literature for standard constructs. Most patients had an uneventful postoperative course. The early complications observed led us to very carefully select the indications. Long-term follow-up is essential.

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.

Guidelines for management of scoliosis in Rett syndrome patients based on expert consensus and clinical evidence

STUDY DESIGN

Modified Delphi technique.

OBJECTIVE

To develop guidelines for the clinical management of scoliosis in Rett syndrome through evidence review and consensus expert panel opinion.

SUMMARY OF BACKGROUND DATA

Rett syndrome is a rare disorder and clinical expertise is thus with small case series. Scoliosis is a frequent association and the evidence base dealing with scoliosis management in this syndrome is limited. Parents of affected girls and women have expressed needs for more information about scoliosis and Rett syndrome.

METHODS

An initial draft of scoliosis guidelines was created based on literature review and open-ended questions where the literature was lacking. Perspectives of four parents of Rett syndrome patients informed this initial draft. Access to an online and a Microsoft Word formatted version of the draft were then sent to an international, multidisciplinary panel of clinicians via e-mail with input sought using a 2-stage modified Delphi process to reach consensus agreement. Items included clinical monitoring and intervention before the diagnosis of scoliosis; monitoring after the diagnosis of scoliosis; imaging; therapy and conservative management; bracing; and preoperative, surgical, and postoperative considerations.

RESULTS

The first draft contained 71 statements, 65 questions. The second draft comprised 88 items with agreement to strong agreement achieved on 85, to form the final guideline document. A comprehensive, life-span approach to the management of scoliosis in Rett syndrome is recommended that takes into account factors such as physical activity, posture, nutritional and bone health needs. Surgery should be considered when the Cobb angle is approximately 40 degrees to 50 degrees and must be supported by specialist management of anesthesia, pain control, seizures, and early mobilization.

CONCLUSION

Evidence- and consensus-based guidelines were successfully created and have the potential to improve care of a complex comorbidity in a rare condition and stimulate research to improve the current limited evidence base.

Perioperative blood transfusion requirements in pediatric scoliosis surgery: the efficacy of tranexamic acid

BACKGROUND

Previous studies have noted that the use of antifibrinolytic medications can help reduce blood loss and transfusion requirements during cardiac, total joint arthroplasty, and spine surgery. Tranexamic acid (TXA) has been investigated in these patient groups but consensus with respect to the dosing regimen has not been achieved, especially in the pediatric scoliosis literature. The purpose of this study was to compare the effects of 2 TXA dosing regimens on reducing transfusion requirements.

METHODS

A retrospective chart review was performed on all idiopathic scoliosis patients undergoing posterior spinal instrumentation and fusion from 2005 to 2006 to determine total perioperative transfusion requirements. Transfusion requirements for those patients receiving either a low (10 mg/kg loading, 1 mg/kg/h infusion) or high (20 mg/kg loading, 10 mg/kg/h infusion) dose of TXA were compared.

RESULTS

High-dose TXA (n = 11) showed a trend toward a reduction in transfusion requirements compared with the low dose (n = 15) for idiopathic scoliosis patients undergoing posterior only instrumentation and fusion (687.9 +/- 778.1 mL vs 1372.6 +/- 1077.3 mL; P = 0.07; 95% confidence interval for the mean difference, -66.3 mL to 1435.7 mL). Although substantial, this difference was underpowered to show a difference.

CONCLUSIONS

The use of the higher dose of TXA resulted in a 50% reduction in transfusion requirements for idiopathic scoliosis patients. Given previous studies, there appears to be a dose-response effect. A prospective dose-ranging study is now required to determine the optimal dose for pediatric patients with idiopathic scoliosis.

LEVEL OF EVIDENCE

III, retrospective cohort study.

Role of Amicar in surgery for neuromuscular scoliosis

STUDY DESIGN

A retrospective case-control study.

OBJECTIVE

Evaluate the effectiveness of Amicar in decreasing perioperative blood loss in patients with neuromuscular scoliosis undergoing posterior spinal fusion (PSF) and segmental spinal instrumentation (SSI).

SUMMARY OF BACKGROUND DATA

Previously, a preliminary prospective; prospective randomized double-blind; same-day anterior and posterior spinal fusion; and fibrinogen studies have demonstrated Amicar to be effective in decreasing total perioperative blood loss and transfusion requirements in surgery for idiopathic scoliosis. Increased fibrinogen secretion is a possible explanation. We are now analyzing its effectiveness in neuromuscular scoliosis.

METHODS

Amicar was administered at 100 mg/kg over 15 minute not to exceed 5 g after anesthesia induction. Maintenance is 10 mg/kg/h until wound closure. There were 2 study groups: group 1 (n = 34), no Amicar and group 2 (n = 62) who received Amicar. The majority of patients in both groups had cerebral palsy. Total perioperative blood loss was determined from the estimated intraoperative blood loss and measured postoperative suction drainage. Total perioperative blood loss and transfusion requirements (cell saver and allogeneic) were compared using chi or Fisher exact test.

RESULTS

There was statistically less estimated intraoperative blood loss, total perioperative blood loss, and transfusion requirements in group 2. Postoperative suction drainage was also less but did not reach statistical significance. In group 1, estimated intraoperative blood loss, measured postoperative suction drainage, and total perioperative blood loss were 2194 +/- 1626 mL, 903 +/- 547 mL, and 3055 +/- 1852 mL, whereas in group 2, it was 1125 +/- 715 mL, 695 +/- 489 mL, and 1805 +/- 940 mL. Transfusion requirements were 1548 +/- 962 mL in group 1 but only 660 +/- 589 mL in group 2 (P < 0.0001). Amicar was equally effective in all diagnoses. There were no complications related to the use of Amicar.

CONCLUSION

Amicar was highly effective in decreasing perioperative blood loss and transfusion requirements in patients with neuromuscular scoliosis undergoing PSF and SSI. It was most effective in decreasing estimated intraoperative blood loss. This results in decreased transfusion requirements, costs, and potential transfusion-related complications.

Blood conservation techniques in spinal deformity surgery: a retrospective review of patients refusing blood transfusion

STUDY DESIGN

A retrospective review.

OBJECTIVE

To review the effectiveness of blood conservation techniques in the spinal fusion of patients that refuse blood transfusion; specifically the Jehovah's witnesses population.

SUMMARY OF BACKGROUND

Spinal surgery can be challenging in patients refusing blood transfusion. There is paucity in the literature examining blood conservation techniques in spinal surgery.

METHODS

The radiographic and medical records of 19 Jehovah's witnesses patients who underwent spinal deformity surgery at a single institution between 2000 and 2003 were reviewed. Patients were assessed for excessive blood loss (EBL), deformity correction, operative time, perioperative complications, and hospital stay. At latest follow-up (mean, 40 months; range, 8-76) the patients were examined for radiographic fusion, progression and complications.

RESULTS

Spinal fusion was attempted in 19 patients, with a mean age of 17 years (range, 10-36 years). All 19 patients were identified through the "Bloodless Surgery Program." Hypotensive anesthesia, hemodilution, and cell saver was employed for all 19 cases. Erythropoietin with supplemental iron was used in 15 patients. Aprotinin was used in 3 patients. EBL and blood returned by cell saver averaged 855 and 341 mL, respectively. Operative times average 315 minutes. The average drop in hemoglobin from after surgery was 3.1 g/dL. There were 2 intraoperative complications: (i) transient loss of somatosensory evoked potential/motor evoked potential signals; and (ii) one surgery abandoned due to EBL. The average spinal deformity correction was 58%. There were 3 postoperative complications, none related to their refusal of a transfusion. 17 patients were available for radiographic and clinic follow-up of at least 24 months. All displayed radiographic fusion without progression.

CONCLUSION

These blood conservation techniques allow satisfactory completion of deformity surgery on those patients not willing to be transfused and without major anesthetic or medical complications.

Coeliac axis thrombosis after surgical correction of spinal deformity in type VI Ehlers-Danlos syndrome: a case report and review of the literature

STUDY DESIGN

An unusual case of postoperative thrombosis of celiac artery in a patient of Type VI Ehlers-Danlos syndrome (EDS) with severe kyphotic deformity is reported.

OBJECTIVE

To describe an unusual complication of celiac artery thrombosis following surgical correction of kyphotic deformity in Type VI EDS.

SUMMARY OF BACKGROUND DATA

Neurologic deficit following surgical correction for kyphoscoliotic deformities in patients with Type VI has been reported in 4 cases previously. There has been no previous report of combined celiac artery thrombosis leading to infarction of major abdominal organs along with quadriparesis below C7-C8.

METHODS

Case report and literature review.

RESULTS

Subsequent to a 2-stage surgical correction with posterior instrumentation and fusion of spine, this patient with Type VI EDS developed celiac artery thrombosis leading to infarction of major abdominal organs. At laparotomy, he required hemihepatectomy, splenectomy, cholecystectomy, and a repair of gastric perforation. Following his abdominal catastrophe, he developed quadriparesis possibly due to anterior spinal artery ischemia.

CONCLUSION

Spine surgeons treating Type VI EDS with progressive kyphoscoliosis should be aware of such an unusual complication of celiac artery occlusion in late postoperative period. Preoperative antithrombotic medication should be monitored carefully to avoid such catastrophic complication. The prognosis remains poor following anterior spinal artery ischemia due to infarction or thrombosis.

Minimizing perioperative blood loss and transfusions in children

PURPOSE

To summarize the physiology and pathophysiology relevant to perioperative blood loss in children. Strategies to reduce blood losses are reviewed.

METHODS

The literature was reviewed using the electronic library PUBMED and the Cochrane Database of Systematic Reviews. Relevant studies published in English or French with an English abstract are included. The following keywords were used: children, blood transfusion, surgical blood loss, erythropoietin, autologous blood, red blood cell saver, normovolemic hemodilution, desmopressin, aminocaproic acid, tranexamic acid, aprotinin, cardiac surgery, liver transplantation and scoliosis surgery.

MAIN FINDINGS

For patients with idiopathic scoliosis, predonation with or without the addition of erythropoietin is a safe and effective way to avoid the use of allogenic blood products. For open heart procedures: whole blood of less than 48 hr is helpful for children of less than two years of age undergoing complex procedures; tranexamic acid may be helpful for cyanotic heart disease and, to a lesser degree, for reoperations; while anti-kallikrein blood levels of aprotinin may both reduce the need for allogenic blood transfusions and improve postoperative oxygenation in infants.

CONCLUSION

Reducing perioperative allogenic blood transfusions is possible in pediatric patients provided that prophylactic measures are adapted to age, disease and type of surgery.

Recombinant coagulation factor VIIa--a novel haemostatic agent in scoliosis surgery?

Spinal fusion surgery in children and adolescents with idiopathic scoliosis is often associated with severe haemorrhage. Recombinant coagulation factor VIIa (rFVIIa) has previously been shown to be an effective haemostatic treatment for severe bleeding associated with a variety of coagulopathic and non-coagulopathic indications. The aim of this retrospective study was to assess the safety and haemostatic efficacy of rFVIIa in a series of 26 consecutive adolescent patients with scoliosis (22 females; mean age 16.6 years) undergoing correctional surgery. A second series of 26 consecutive patients (20 females; mean age 16.2 years) who received standard therapy during surgery, represented historical controls. Blood loss, transfusion requirements, duration of surgery, and peri-operative measurements of coagulation parameters were compared between the two groups. Intra-operative and combined intra-operative and post-operative blood losses were significantly smaller in the rFVIIa-treatment group than in the historical controls (P=0.003 and 0.032, respectively); rFVIIa-treated patients also demonstrated significantly reduced blood loss per vertebral segment fused (P=0.032) and per hour of surgery (P<0.001). Intra-operative requirements for packed red blood cells were also significantly lower in the treatment group (P=0.042). Patients in the treatment group demonstrated rapid and maintained reduction of prothrombin time and international normalised ratio; values among rFVIIa-treated patients remained significantly lower than those in the control group at all time points evaluated (P<0.001). There were no deaths and no adverse events. These results suggest that rFVIIa is a safe and effective haemostatic agent for use during spinal fusion surgery in adolescent patients with idiopathic scoliosis; however, further research and randomised, placebo-controlled trials are needed to confirm these findings.

Severe blood loss during spinal reconstructive procedures: The potential usefulness of topical hemostatic agents

Complex spinal reconstructive procedures are invariably associated with excessive intraoperative blood loss that significantly increases the risk of severe perioperative complications. In some cases, excessive hemorrhage is equivalent to estimated total blood volume. Unfortunately, widely exposed bony surfaces are not amenable to standard hemostatic maneuvers utilized during soft tissue surgery. This article evaluates the clinical effectiveness of several approaches to blood management in this setting, and hypothesizes that underappreciated topical hemostatic agents may provide benefit by reducing the need for autologous predonation, banked donor blood or antifibrinolytic agents. Topical agents combining collagen, thrombin and fibrin have demonstrated initial promise by inducing platelet aggregation and initiating the clotting cascade when applied directly to bleeding bony sites. Clinical studies are clearly warranted.

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.

Clotting parameters and thromboelastography in children with neuromuscular and idiopathic scoliosis undergoing posterior spinal fusion

STUDY DESIGN

An unblinded comparison of laboratory values between patients with idiopathic and neuromuscular scoliosis.

OBJECTIVES

To compare standard tests of coagulation and thromboelastography (TEG) parameters between two groups of patients undergoing posterior spinal fusion (PSF).

SUMMARY OF BACKGROUND DATA

Children with neuromuscular scoliosis such as cerebral palsy have more intraoperative blood loss than children with idiopathic scoliosis during PSF. Various reasons suggested for this include nutritional deficiencies, altered tissue integrity, hepatic dysfunction, and use of antiepileptic medications that can cause poor hemostasis and altered coagulation. We have observed alterations in coagulation factor levels in patients with cerebral palsy due to spastic quadriplegia with moderate blood volume loss (25% estimated blood volume).

METHODS

In a prospective analysis, we compared standard tests of coagulation (prothrombin time [PT], partial thromboplastin time [PTT], platelet count, fibrinogen levels) and TEG at baseline and at a blood loss of 15% estimated blood volume in patients with idiopathic scoliosis and cerebral palsy undergoing PSF.

RESULTS

There were no differences between the groups in terms of gender distribution and age. There was a significant difference between the baseline PT and PTT values, although both groups were within laboratory norms. After 15% blood volume loss, there were differences seen in the PT, PTT, maximum amplitude on the TEG, ionized calcium, and serum magnesium levels (P < 0.05).

CONCLUSIONS

Children with cerebral palsy undergoing PSF have increased bleeding that starts earlier in the procedure than it does for patients with idiopathic scoliosis undergoing PSF. We found that, even though children with spastic quadriplegia had baseline PT and PTT values within normal limits, they were significantly different when compared with normal patients.

Anaesthesia for spinal surgery in adults

The spectrum of spinal surgery in adult life is considerable. Anaesthesia for major spinal surgery, such as spinal stabilization following trauma or neoplastic disease, or for correction of scoliosis, presents a number of challenges. The type of patients who would have been declined surgery 20 yr ago for medical reasons, are now being offered extensive procedures. They commonly have preoperative co-morbid conditions such as serious cardiovascular and respiratory impairment. Airway management may be difficult. Surgery imposes further stresses of significant blood loss, prolonged anaesthesia, and problematical postoperative pain management. The perioperative management of these patients is discussed. The advent of techniques to monitor spinal cord function has reduced postoperative neurological morbidity in these patients. The anaesthetist has an important role in facilitating these methods of monitoring.

Efficacy of aprotinin in reducing blood loss in spinal fusion for idiopathic scoliosis

Aprotinin is a proteinase inhibitor with antifibrinolytic properties that has found widespread application during cardiac surgical procedures due to its ability to decrease blood loss and transfusion requirements. Recently it has been used by orthopedic surgeons in hip replacement and other major surgeries except for scoliosis surgery, which is known to be associated with major blood loss. To evaluate the effect of aprotinin in reducing blood loss during spinal fusion surgery for idiopathic scoliosis, a double-blind randomized prospective clinical study was performed. Forty-three patients with idiopathic scoliosis underwent spinal fusion and instrumentation and were divided randomly into two groups. Fifteen patients received aprotinin, whereas 28 patients received placebo. The aprotinin group had less blood loss than the placebo group. The transfusion requirement was less in the aprotinin group than the placebo group. Although the difference was not significant statistically, the benefit of aprotinin in reducing blood loss in spinal surgery for idiopathic scoliosis was consistent.

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.

The Use of DDAVP Desmopressin Reduces the Incidence of Microhematomas After Facioplasty

The authors began to use 1-desamino-8-D-arginine vasopressin (DDAVP) Desmopressin Acetate routinely in their facelift patients who had a relatively high risk of bleeding, either from Von Willebrand factor deficiency, platelet dysfunction, aspirin intake, or ease of ecchymosis. Based on their observations that these patients had enhanced clotting and recovery times, they decided to undertake a prospective evaluation of the effects of Desmopressin Acetate when administered as a preoperative intravenous supplement during cosmetic facioplasty. A series of 200 consecutive patients undergoing surgery was divided into control and treatment groups. A total of 100 patients did not receive medication perioperatively, and 100 subsequent patients received preoperative DDAVP. All patients were observed for ecchymosis and swelling postoperatively and were graded by our postsurgical management team. Postsurgical ecchymosis was graded as mild (grade 1), moderate (grade 2), or severe (grade 3). Grade 4 indicated an expanding hematoma that required immediate surgical intervention. Grades 1 and 2 ecchymosis resolved within 3 weeks. Grade 3 ecchymosis or microhematomas required intervention such as needle aspiration or massage therapy. These small collections of blood generally required substantially longer to resolve and generated notable anxiety in the patients involved. Patients were excluded from the trial if there was a previous history of hypercoagulability or because treatment with DDAVP was medically contraindicated. A total of 23% of untreated patients required intervention for grade 3 ecchymosis compared with 3% of DDAVP-treated patients. No patients experienced any complications associated with DDAVP--namely, deep vein thrombosis, pulmonary embolus, electrolyte imbalance, or renal insufficiency. The authors undertook this study to determine whether DDAVP would help to decrease the incidence of microhematomas after facelift. Based on the results of their grading system and study, they think that the use of DDAVP is safe and efficacious in the prevention of troublesome microhematomas after facelift. Interestingly, although their male facelift patients challenged their efforts to obtain satisfactory hemostasis during and after surgery, the DDAVP-treated male patients responded with marked improvement in postoperative grading after treatment. Obtaining hemostasis intraoperatively was facilitated as well in these patients. This gender phenomenon was even more dramatic when compared with our female patient population.

Desmopressin for minimising perioperative allogeneic blood transfusion

BACKGROUND

Public concerns regarding the safety of transfused blood have prompted re-consideration of the use of allogeneic (from an unrelated donor) red blood cell (RBC) transfusion, and a range of techniques designed to minimise transfusion requirements.

OBJECTIVES

To examine the evidence for the efficacy of desmopressin (1-deamino-8-D-arginine-vasopressin), in reducing perioperative blood loss and the need for red cell transfusion in patients who do not have congenital bleeding disorders.

SEARCH STRATEGY

Articles were identified by: computer searches of OVID MEDLINE, EMBASE, and Current Contents (to August 2000) and web sites of international health technology assessment agencies (to May 1998). References in the identified trials and review articles were checked and authors contacted to identify additional studies.

SELECTION CRITERIA

Randomised controlled parallel group trials in which adult patients, scheduled for non-urgent surgery, were randomised to DDAVP, or to a control group, who did not receive the intervention.

DATA COLLECTION AND ANALYSIS

Trial quality was assessed using criteria proposed by Schulz et al. (1995) and Jadad et al. (1996). The principal outcomes were: the number of patients exposed to red cells, and the amount of blood transfused. Other clinical outcomes are detailed in the review.

MAIN RESULTS

Fourteen trials of DDAVP (N=1034) reported data on the proportion of patients exposed to allogeneic RBC transfusion. In subjects treated with DDAVP the relative risk of exposure to peri-operative allogeneic blood transfusion was 0.98 (95%CI: 0.88 to 1.10) compared with control. In DDAVP-treated patients the relative risk of requiring re-operation due to bleeding was 0.56 (95%CI: 0.18 to 1.73). There was no statistically significant effect overall for mortality and non-fatal myocardial infarction in DDAVP-treated patients compared with control (RR=1.53: 95%CI: 0.58 to 4.05) and (RR=1.52: 95%CI: 0.67 to 3.49) respectively.

REVIEWER'S CONCLUSIONS

There is no convincing evidence that desmopressin minimises perioperative allogeneic RBC transfusion in patients who do not have congenital bleeding disorders. These data suggest that there is no benefit of using DDAVP as a means of minimising perioperative allogeneic RBC transfusion. This meta-analysis had 90% power to detect a relative risk reduction of at least 17% for receiving a red cell transfusion at alpha = 0.05 (two-sided).