Aprotinin and transfusion requirements in pediatric craniofacial surgery

Perioperative anaphylaxis to fibrin sealants in children with Noonan Syndrome: A retrospective study

BACKGROUND

In the diagnosis of perioperative anaphylaxis, it is essential to define its cause to prevent future reexposures, especially in children with Noonan Syndrome who are characterized by a large number of systemic features and wide-ranging dysmorphia. From an oral surgeon's point of view, apart from an increased risk of tumor incidence, diverse hematologic anomalies are of high concern.

OBJECTIVE

Perioperative management of such patients often requires the use of fibrin sealants, which contain aprotinin. A certain number of anaphylaxis cases have been observed in our daily practice during such treatment, which was the reason for this evaluation.

METHODS

The study was conducted to retrospectively review perioperative anaphylaxis grade II and above in children with Noonan Syndrome who underwent surgeries in the Department of Oral Surgery, Medical University of Lodz, between 2006 and 2021.

RESULTS

Out of the 16 cases of suspected anaphylaxis to aprotinin, 14 were observed in children with Noonan Syndrome. The postoperative serologic screening revealed positive results for qualitative aprotinin-specific immunoglobulin (Ig) G, highly elevated quantitative aprotinin-specific IgG, and slightly elevated aprotinin-specific IgE antibodies. Interestingly, previous aprotinin administration or contact in the past 12 months was excluded.

CONCLUSION

Given that fibrin sealants are typically used in various surgical practices and although the anaphylaxis reactions in such cases are rare, it is essential to be cautious in patients with RASopathies who are at a high risk of developing anaphylaxis.

Safety and efficacy of aprotinin versus tranexamic acid for reducing absolute blood loss and transfusion in pediatric patients undergoing craniosynostosis surgery: a randomized, double-blind, three-arm controlled trial

OBJECTIVE

Craniosynostosis surgery is associated with considerable blood loss and need for transfusion. Considering the lower estimated blood volume (EBV) of children compared to adults, excessive blood loss may quickly lead to hypovolemic shock. Therefore, reducing blood loss is important in craniosynostosis surgery. This study was conducted to evaluate the efficacy of aprotinin or tranexamic acid (TXA) in blood loss reduction in these patients.

METHODS

In the current randomized controlled trial, 90 eligible pediatric patients with craniosynostosis were randomly divided into three groups to receive either aprotinin, TXA, or no intervention. The absolute blood loss and transfusion amount were assessed for all patients both intraoperatively and 2 and 8 hours postoperatively.

RESULTS

Although crude values of estimated blood loss were not significantly different between groups (p = 0.162), when adjusted to the patient's weight or EBV, the values reached the significance level (p = 0.018), particularly when the aprotinin group was compared to the control group (p = 0.0154). The EBV losses 2 hours and 8 hours postoperatively significantly dropped in the TXA and aprotinin groups compared to the control group (p = 0.001 and p < 0.001, respectively). Rates of postoperative blood transfusion were significantly higher in the control group (p = 0.024). Hemoglobin and hematocrit 8 hours postoperatively were lower in the control group than in the TXA or aprotinin treatment groups (p < 0.002 and p < 0.001, respectively). There were no serious adverse events associated with the interventions in this study.

CONCLUSIONS

Aprotinin and TXA can reduce blood loss and blood transfusion without serious complications and adverse events in pediatric patients undergoing craniosynostosis surgery.

Efficacy and Safety of Antifibrinolytic Drugs in Pediatric Surgery: A Systematic Review

Antifibrinolytic drugs are used to reduce blood loss and subsequent transfusions during surgery and following trauma, but the optimal dosing regimen in the pediatric population is still unresolved. The aim of this systematic review was to evaluate efficacy and safety of antifibrinolytic drugs in pediatric surgery and trauma to determine the optimal dosing regimen. A literature search was performed in PubMed, Embase, Cochrane, and Web of Science on May 3, 2020. We included randomized controlled studies investigating the effect of tranexamic acid (TXA), aprotinin, and epsilon-aminocaproic acid, in terms of reducing blood loss, blood transfusions, reoperations, and rebleeds in pediatric patients aged 0 to 18 years undergoing cardiac surgery, noncardiac surgery, or trauma. Fifty randomized controlled trials (RCTs) were included; 28 RCTs investigated cardiac surgery and 22 investigated noncardiac surgery. No RCTs regarding trauma met the inclusion criteria. All antifibrinolytic drugs reduced postoperative blood loss and transfusions when used in pediatric surgery. The dosing regimen varied between studies, but similar effect sizes were found in terms of reduced blood loss regardless of the cumulative dose used. Few studies found adverse events, and no difference in incidence or type of adverse events was seen between the antifibrinolytic and the placebo group. In conclusion, use of antifibrinolytics is efficient and safe in children undergoing surgery. We propose TXA as the drug of choice based on its level of evidence and safety profile; we recommend a dosing regimen composed of a loading dose of 10 to 15 mg/kg prior to surgery followed by 1 to 5 mg/kg/h as continuous infusion throughout surgery.

Anesthetic Considerations for Pediatric Craniofacial Surgery

Anesthetic management of craniosynostosis remains a challenging experience. It requires input and collaboration from multiple specialties to improve patient outcomes. Understanding the surgical corrective techniques and the underlying risks of each is essential to providing the best care to this patient population. The propensity for significant blood loss necessitates fundamental knowledge of pediatric resuscitation and the development of perioperative transfusion protocols that have been shown to reduce transfusion requirements in the peri-operative period.

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.

Use of blood-sparing surgical techniques and transfusion algorithms: association with decreased blood administration in children undergoing primary open craniosynostosis repair

OBJECT Craniofacial reconstruction surgery (CFR) is often associated with significant blood loss, coagulopathy, and perioperative blood transfusion. Due to transfusion risks, many different approaches have been used to decrease allogeneic blood transfusion for these patients during the perioperative period. Protocols have decreased blood administration during the perioperative period for many types of surgeries. The object of this study was to determine if a protocol involving blood-sparing surgical techniques and a transfusion algorithm decreased intraoperative blood transfusion and blood loss. METHODS A protocol using transfusion algorithms and implementation of blood-sparing surgical techniques for CFR was implemented at Vanderbilt University on January 1, 2013. Following Institutional Review Board approval, blood loss and transfusion data were gathered retrospectively on all children undergoing primary open CFR, using the protocol, for the calendar year 2013. This postprotocol cohort was compared with a preprotocol cohort, which consisted of all children undergoing primary open CFR during the previous calendar year, 2012. RESULTS There were 41 patients in the preprotocol and 39 in the postprotocol cohort. There was no statistical difference between the demographics of the 2 groups. When compared with the preprotocol cohort, intraoperative packed red blood cell transfusion volume decreased from 36.9 ± 21.2 ml/kg to 19.2 ± 10.9 ml/kg (p = 0.0001), whereas fresh-frozen plasma transfusion decreased from 26.8 ± 25.4 ml/kg to 1.5 ± 5.7 ml/kg (p < 0.0001) following implementation of the protocol. Furthermore, estimated blood loss decreased from 64.2 ± 32.4 ml/kg to 52.3 ± 33.3 ml/kg (p = 0.015). Use of fresh-frozen plasma in the postoperative period also decreased when compared with the period before implementation of the protocol. There was no significant difference in morbidity and mortality between the 2 groups. CONCLUSIONS The results of this study suggested that using a multidisciplinary protocol consisting of transfusion algorithms and implementation of blood-sparing surgical techniques during major CFR in pediatric patients is associated with reduced intraoperative administration of blood product, without shifting the transfusion burden to the postoperative period.

Bleeding management for pediatric craniotomies and craniofacial surgery

Pediatric patients when undergoing craniotomies and craniofacial surgery may potentially have significant blood loss. The amount and extent will be dictated by the nature of the surgical procedure, the proximity to major blood vessels, and the age, and weight of the patient. The goals should be to maintain hemodynamic stability and oxygen carrying capacity and to prevent and treat hyperfibrinolysis and dilutional coagulopathy. Over transfusion and transfusion-related side effects should be minimized. This article will highlight the pertinent considerations for managing massive blood loss in pediatric patients undergoing craniotomies and craniofacial surgery. North American and European guidelines for intraoperative administration of fluid and blood products will be discussed.