Comparison of perioperative blood salvage and postoperative reinfusion of drained blood during surgical correction of craniosynostosis in infants

Optimizing Blood Loss and Management in Craniosynostosis Surgery: A Systematic Review of Outcomes Over the Last 40 Years

Surgical correction of craniosynostosis can involve significant blood loss. Rates of allogenic blood transfusion have been reported to approach 100%. Multiple interventions have been described to reduce blood loss and transfusion requirements. The aim of this study was to analyze various approaches over the last 4 decades to optimize blood loss and management during craniosynostosis surgery.

PRISMA guidelines for systematic reviews were followed. PubMed and Cochrane database searches identified studies analyzing approaches to minimizing blood loss or transfusion rate in craniosynostosis surgery.

Primary outcomes included rate or amount of allogenic or autologous blood transfusion, estimated blood loss (EBL), postoperative hemoglobin (Hg), or hematocrit (Hct) levels. Secondary outcomes were examined when reported.

Fifty-two studies met inclusion criteria. There was marked heterogeneity regarding design, inclusion criteria, surgical intervention, and endpoints. The majority of the studies were nonrandomized and noncomparative. Four studies analyzed erythropoietin (EPO), 6 analyzed various cell-saver (CS) technologies, 18 analyzed antifibrinolytics (tranexamic acid [TXA], aminocaproic acid [ACA], and aprotinin [APO]), 8 analyzed various alternatives, and 16 analyzed multimodal pathways & protocols. Some studies analyzed multiple approaches.

Although the majority of studies reviewed represent level III/IV evidence, several high-quality level I studies were identified and included. Level I evidence supported an improvement in blood outcomes by utilizing EPO, CS, and TXA, individually or in concert with one another. Thus, this review suggests that a multi-prong approach may be the most effective means to optimize blood loss and transfusion outcomes in craniosynostosis surgery.

The Funnel: From the Skull Base to the Sacrum. New Trends and Technologies in Anaesthesia for the Adult Patient

The management of children affected by neurosurgical pathologies is multidisciplinary and should be set on several fronts.The potential need for massive blood components transfusions, the prolonged anaesthesia in paediatric age that may be often complicated by various forms of syndrome-related problems, and airway management are often encountered.The problems may be divided schematically into three large groups: preoperative, intraoperative and postoperative problems.The aim of this work is to optimize and make paediatric neurosurgery safe by highlighting the most important aspects in the various perioperative phases.

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.

Patient Blood Management in Pediatric Cardiac Surgery: A Review

Efforts to reduce blood product transfusions and adopt blood conservation strategies for infants and children undergoing cardiac surgical procedures are ongoing. Children typically receive red blood cell and coagulant blood products perioperatively for many reasons, including developmental alterations of their hemostatic system, and hemodilution and hypothermia with cardiopulmonary bypass that incites inflammation and coagulopathy and requires systemic anticoagulation. The complexity of their surgical procedures, complex cardiopulmonary interactions, and risk for inadequate oxygen delivery and postoperative bleeding further contribute to blood product utilization in this vulnerable population. Despite these challenges, safe conservative blood management practices spanning the pre-, intra-, and postoperative periods are being developed and are associated with reduced blood product transfusions. This review summarizes the available evidence regarding anemia management and blood transfusion practices in the perioperative care of these critically ill children. The evidence suggests that adoption of a comprehensive blood management approach decreases blood transfusions, but the impact on clinical outcomes is less well studied and represents an area that deserves further investigation.

Intraoperative and postoperative complications in the surgical treatment of craniosynostosis: minimally invasive versus open surgical procedures

OBJECTIVE To compare minimally invasive endoscopic and open surgical procedures, to improve informed consent of parents, and to establish a baseline for further targeted improvement of surgical care, this study evaluated the complication rate and blood transfusion rate of craniosynostosis surgery in our department. METHODS A prospective complication registration database that contains a consecutive cohort of all pediatric neurosurgical procedures in the authors' neurosurgical department was used. All pediatric patients who underwent neurosurgical treatment for craniosynostosis between February 2004 and December 2014 were included. In total, 187 procedures were performed, of which 121 were endoscopically assisted minimally invasive procedures (65%). Ninety-three patients were diagnosed with scaphocephaly, 50 with trigonocephaly, 26 with plagiocephaly, 3 with brachycephaly, 9 with a craniosynostosis syndrome, and 6 patients were suffering from nonsyndromic multisutural craniosynostosis. RESULTS A total of 18 complications occurred in 187 procedures (9.6%, 95% CI 6.2-15), of which 5.3% (n = 10, 95% CI 2.9-10) occurred intraoperatively and 4.2% (n = 8, 95% CI 2.2-8.2) occurred postoperatively. In the open surgical procedure group, 9 complications occurred: 6 intraoperatively and 3 postoperatively. In the endoscopically assisted procedure group, 9 complications occurred: 4 intraoperatively and 5 postoperatively. Blood transfusion was needed in 100% (n = 66) of the open surgical procedures but in only 21% (n = 26, 95% CI 15-30) of the endoscopic procedures. One patient suffered a transfusion reaction, and 6 patients suffered infections, only one of which was a surgical site infection. A dural tear was the most common intraoperative complication that occurred (n = 8), but it never led to postoperative sequelae. Intraoperative bleeding from a sagittal sinus occurred in one patient with only minimal blood loss. There were no deaths, permanent morbidity, or neurological sequelae. CONCLUSIONS Complications during craniosynostosis surgery were relatively few and minor and were without permanent sequelae in open and in minimally invasive procedures. The blood transfusion rate was significantly reduced in endoscopic procedures compared with open procedures.

Minimizing blood transfusions in the surgical correction of craniosynostosis: a 10-year single-center experience

INTRODUCTION

Our center previously reported low transfusion rates for craniosynostosis surgery by two experienced neurosurgeons using standard intraoperative techniques and acceptance of low hemoglobin levels. This study evaluated whether low rates were maintained over the last 10 years and if a less experienced neurosurgeon, trained in and practicing in the same environment, could achieve similar outcomes.

METHODS

All craniosynostosis operations performed in children between 2004 and 2015 were reviewed retrospectively. Transfusion rates were calculated. Analyses examined the relationship of transfusion to craniosynostosis type, surgical procedure, redo operation, surgeon, and perioperative hemoglobin levels.

RESULTS

Two hundred eighteen patients were included: 71 open sagittal, 28 endoscopic-assisted sagittal, 32 unicoronal, 14 bicoronal, 42 metopic, and 31 multisuture. Median age at operation was 9.1 months. Overall transfusion rate was 24 %: 17 % open sagittal, 7 % endoscopic-assisted sagittal, 6 % unicoronal, 21 % bicoronal, 45 % metopic, and 45 % multisuture. The timing of transfusions were 75, 21, and 4 % for intraoperative, postoperative, and both, respectively. Patients not receiving transfusion had a mean lowest hemoglobin of 87 g/l (range 61-111) intraoperatively and 83 g/l (range 58-115) postoperatively. Mean lowest hemoglobin values were significantly lower in those necessitating intraoperative (75 g/l, range 54-102) or postoperative (59 g/l, range 51-71) transfusions. There was no significant difference in transfusion rate between less and more experienced surgeons. There were no cardiovascular complications or mortalities.

CONCLUSION

In craniosynostosis surgery, reproducible, long-term low blood transfusion rates were able to be maintained at a single center by careful intraoperative technique and acceptance of low intraoperative and postoperative hemoglobin levels in hemodynamically stable patients. Furthermore, low rates were also achieved by an inexperienced neurosurgeon in the group. This suggests that these results may be achievable by other neurosurgeons, who follow a similar protocol.

Noninvasive cardiac output measurement using bioreactance in postoperative pediatric patients

BACKGROUND

Thoracic bioreactance is a noninvasive and continuous method of cardiac output (CO) measurement that is being developed in adult patients. Very little information is available on thoracic bioreactance use in children.

OBJECTIVE

The aim of the study was to evaluate the ability of a bioreactance device (NICOM(®) ; Cheetah Medical, Tel Aviv, Israel) to estimate CO and to track changes in CO induced by volume expansion (VE) in children.

METHODS

Cardiac output values obtained using the NICOM(®) device (CONICOM ) and measured by trans-thoracic echocardiography (COTTE ) were compared in pediatric neurosurgical patients during the postoperative period.

RESULTS

Seventy-three pairs of measurements of CO obtained in 30 children were available for analysis. The bias (lower and upper limits of agreement) between CONICOM and COTTE was -0.11 (-1.4 to 1.2) l·min(-1). The percentage error (PE) was 55%. The precision of the NICOM(®) device was 45%. A significant correlation was observed between the CO values obtained using the two methods (r = 0.89, <0.001). The concordance percentage between changes in COTTE and CON icom induced by VE was 84% following exclusion of patients with changes in CO <15% (n = 5).

CONCLUSIONS

The PE observed is too large, and the limits of agreement too wide, to enable us to comment on the equivalence of the two techniques of CO measurements. However, the NICOM(®) device performs well in tracking changes in CO following VE.

Minimizing transfusion requirements for children undergoing craniosynostosis repair: the CHoR protocol

OBJECT

Children with craniosynostosis may require cranial vault remodeling to prevent or relieve elevated intracranial pressure and to correct the underlying craniofacial abnormalities. The procedure is typically associated with significant blood loss and high transfusion rates. The risks associated with transfusions are well documented and include transmission of infectious agents, bacterial contamination, acute hemolytic reactions, transfusion-related lung injury, and transfusion-related immune modulation. This study presents the Children's Hospital of Richmond (CHoR) protocol, which was developed to reduce the rate of blood transfusion in infants undergoing primary craniosynostosis repair.

METHODS

A retrospective chart review of pediatric patients treated between January 2003 and Febuary 2012 was performed. The CHoR protocol was instituted in November 2008, with the following 3 components; 1) the use of preoperative erythropoietin and iron therapy, 2) the use of an intraoperative blood recycling device, and 3) acceptance of a lower level of hemoglobin as a trigger for transfusion (< 7 g/dl). Patients who underwent surgery prior to the protocol implementation served as controls.

RESULTS

A total of 60 children were included in the study, 32 of whom were treated with the CHoR protocol. The control (C) and protocol (P) groups were comparable with respect to patient age (7 vs 8.4 months, p = 0.145). Recombinant erythropoietin effectively raised the mean preoperative hemoglobin level in the P group (12 vs 9.7 g/dl, p < 0.001). Although adoption of more aggressive surgical vault remodeling in 2008 resulted in a higher estimated blood loss (212 vs 114.5 ml, p = 0.004) and length of surgery (4 vs 2.8 hours, p < 0.001), transfusion was performed in significantly fewer cases in the P group (56% vs 96%, p < 0.001). The mean length of stay in the hospital was shorter for the P group (2.6 vs 3.4 days, p < 0.001).

CONCLUSIONS

A protocol that includes preoperative administration of recombinant erythropoietin, intraoperative autologous blood recycling, and accepting a lower transfusion trigger significantly decreased transfusion utilization (p < 0.001). A decreased length of stay (p < 0.001) was seen, although the authors did not investigate whether composite transfusion complication reductions led to better outcomes.

Anesthesia for craniofacial surgery in infancy

Anesthetic management of infants undergoing craniofacial surgery can be challenging. Primary concerns for the anesthesiologist include blood loss and its management. The evolution of procedures to treat craniosynostosis has resulted in improvements in perioperative morbidity, including decreased blood loss and transfusion, shorter operations, and shorter hospital stays. An understanding of the procedures performed to treat craniosynostosis is necessary to provide optimal anesthetic management. Descriptions of current surgical techniques and approaches to anesthetic care are presented in this review.

Transfusion of cell saver salvaged blood in neonates and infants undergoing open heart surgery significantly reduces RBC and coagulant product transfusions and donor exposures: results of a prospective, randomized, clinical trial

OBJECTIVE

To evaluate whether transfusion of cell saver salvaged, stored at the bedside for up to 24 hrs, would decrease the number of postoperative allogeneic RBC transfusions and donor exposures, and possibly improve clinical outcomes.

DESIGN

Prospective, randomized, controlled, clinical trial.

SETTING

Pediatric cardiac intensive care unit.

PATIENTS

Infants weighing less than 20 kg (n = 106) presenting for cardiac surgery with cardiopulmonary bypass.

INTERVENTIONS

Subjects were randomized to a cell saver transfusion group where cell saver blood was available for transfusion up to 24 hrs after collection, or to a control group. Cell saver subjects received cell saver blood for volume replacement and/or RBC transfusions. Control subjects received crystalloid or albumin for volume replacement and RBCs for anemia. Blood product transfusions, donor exposures, and clinical outcomes were compared between groups.

MEASUREMENTS AND MAIN RESULTS

Children randomized to the cell saver group had significantly fewer RBC transfusions (cell saver: 0.19 ± 0.44 vs. control: 0.75 ± 1.2; p = 0.003) and coagulant product transfusions in the first 48 hrs post-op (cell saver: 0.09 ± 0.45 vs. control: 0.62 ± 1.4; p = 0.013), and significantly fewer donor exposures (cell saver: 0.60 ± 1.4 vs. control: 2.3 ± 4.8; p = 0.019). This difference persisted over the first week post-op, but did not reach statistical significance (cell saver: 0.64 ± 1.24 vs. control: 1.1 ± 1.4; p = 0.07). There were no significant clinical outcome differences.

CONCLUSION

Cell saver blood can be safely stored at the bedside for immediate transfusion for 24 hrs after collection. Administration of cell saver blood significantly reduces the number of RBC and coagulant product transfusions and donor exposures in the immediate postoperative period. Reduction of blood product transfusions has the potential to reduce transfusion-associated complications and decrease postoperative morbidity. Larger studies are needed to determine whether this transfusion strategy will improve clinical outcomes.

Population pharmacokinetics of epsilon-aminocaproic acid in infants undergoing craniofacial reconstruction surgery

BACKGROUND

Understanding the clinical pharmacology of the antifibrinolytic epsilon-aminocaproic acid (EACA) is necessary for rational drug administration in children. The aim of this study is to determine the pharmacokinetics (PKs) of EACA in infants aged 6-24 months undergoing craniofacial reconstruction surgery.

METHODS

Cohorts of six infants were enrolled sequentially to one of the three escalating loading dose-continuous i.v. infusion (CIVI) regimens: 25 mg kg(-1), 10 mg kg(-1) h(-1); 50 mg kg(-1), 20 mg kg(-1) h(-1); 100 mg kg(-1), 40 mg kg(-1) h(-1). Plasma EACA concentrations were determined using a validated high-performance liquid chromatography-tandem mass spectrometry assay. A population non-linear mixed effects modelling approach was used to characterize EACA PKs.

RESULTS

Population PK parameters of EACA were estimated using a two-compartment disposition model with weight expressed as an allometric covariate and an age effect. The typical patient in this study had an age of 38.71 weeks and a weight of 8.82 kg. PK parameters for this typical patient were: pre-/postoperative plasma drug clearance of 32 ml min(-1) (3.6 ml kg(-1) min(-1)), inter-compartmental clearance of 42.4 ml min(-1) (4.8 ml min(-1) kg(-1)), central volume of distribution of 1.27 litre (0.14 litre kg(-1)), and peripheral volume of distribution of 2.53 litre (0.29 litre kg(-1)). Intra-operative clearance and central volume of distribution were 89% and 80% of the pre-/postoperative value, respectively.

CONCLUSIONS

EACA clearance increased with weight and age. The dependence of clearance on body weight supports weight-based dosing. Based on this study, a loading dose of 100 mg kg(-1) followed by a CIVI of 40 mg kg(-1) h(-1) is appropriate to maintain target plasma EACA concentrations in children aged 6-24 months undergoing these procedures.

Scaphocephaly correction with retrocoronal and prelambdoid craniotomies (Renier's "H" technique)

The aim of this paper is to describe the surgical technique, originally devised by Dr. Renier which is currently used to treat children with scaphocephaly under 6 months of age at the Craniofacial Unit of Hopital Necker Enfants Malades (French National Referral Center for Faciocraniosynostosis), focusing on its advantages and limitations.

Posterior remodeling flap for posterior plagiocephaly

INTRODUCTION

Nonsynostotic posterior plagiocephaly has become the most common skull deformation since pediatricians have suggested the supine position for the newborns to reduce the risk of sudden death. Prevention of such a "positional" deformation or its management once it has occurred is mainly based on physical maneuvers such as physiotherapy and active positional corrective measures.

SELECTION CRITERIA

Surgical correction, however, may be suggested in rare cases where deformation of the skull is so severe or the referral of the child is so late that physical corrective treatment cannot be taken into consideration. Surgical management is based on the creation of a posterior bone flap to be repositioned after the opportune contouring and rotation.

PURPOSE

The aim of this paper is to describe the surgical technique used for posterior vault remodeling in posterior plagiocephaly at the craniofacial unit of Hopital Necker Enfants Malades (French National Referral Center for Faciocraniosynostosis) focusing on its advantages and limitations.

Absence of tachycardia during hypotension in children undergoing craniofacial reconstruction surgery

BACKGROUND

Tachycardia is a baroreceptor-mediated response to hypotension. Heart rate (HR) behavior in the setting of hypotension in anesthetized children is not well characterized. We conducted this study to assess the relationship between HR and hypotension in a population of anesthetized children experiencing massive blood loss. Our primary hypothesis was that HR would be increased with the onset of hypotension associated with hypovolemia in comparison with time points without hypotension.

METHODS

We performed a query of our prospective craniofacial perioperative registry for children younger than 24 months who underwent cranial vault reconstruction surgery. Demographic and perioperative data were extracted, and the intraoperative blood loss was calculated. Vital signs were extracted from our computerized anesthesia record and analyzed. Hypotension was defined as a mean arterial blood pressure <40 mm Hg for at least 3 computerized anesthesia record entries (captured every 15 seconds). The preoperative HR, the average HR over the entire intraoperative period, the HR at the onset of hypotension, and the HR 5 minutes before and 5 minutes after the hypotensive episode were compared.

RESULTS

The registry query yielded data from 57 procedures. There were 29 episodes of hypotension occurring in 10 subjects. There was no significant difference in HR at the onset of hypotension (when mean arterial blood pressure decreased below 40 mm Hg) in comparison with the preoperative HR, the average intraoperative HR, or in comparison with 5 minutes before and 5 minutes after the episode of hypotension.

CONCLUSIONS

In this study of anesthetized children younger than 24 months undergoing surgery with massive blood loss, hypotension was not associated with an increased HR. HR does not appear to be a useful indicator of hypovolemia in this population.

Perioperative management of children undergoing craniofacial reconstruction surgery: a practice survey

OBJECTIVE/AIMS

  To assess current practices in the management of children undergoing craniofacial surgery and identify areas of significant practice variability with the intent to direct future research.

BACKGROUND

  The perioperative management of infants and children undergoing craniofacial reconstruction surgery can be challenging because of the routine occurrence of significant blood loss with associated morbidity. A variety of techniques have been described to improve the care for these children. It is presently unknown to what extent these practices are currently employed.

METHODS

  A web-based survey was sent to representatives from 102 institutions. One individual per institution was surveyed to prevent larger institutions from being over-represented in the results.

RESULTS

  Requests to complete the survey were sent to 102 institutions; 48 surveys were completed. The survey was composed of two parts: management of infants undergoing strip craniectomies, and management of children undergoing major craniofacial reconstruction.

CONCLUSIONS

  Significant variability exists in the management of children undergoing these procedures; further study is required to determine the optimal management strategies. Clinical trials assessing the utility of central venous pressure and other hemodynamic monitoring modalities would enable evidence-based decision-making for monitoring in these children. The development of institutional transfusion thresholds should be encouraged, as there exists a body of evidence supporting their efficacy and safety.

An evidence-based approach to craniosynostosis

The Maintenance of Certification module series is designed to help the clinician structure his or her study in specific areas appropriate to his or her clinical practice. This article is prepared to accompany practice-based assessment of preoperative assessment, anesthesia, surgical treatment plan, perioperative management, and outcomes. In this format, the clinician is invited to compare his or her methods of patient assessment and treatment, outcomes, and complications, with authoritative, information-based references. This information base is then used for self-assessment and benchmarking in parts II and IV of the Maintenance of Certification process of the American Board of Plastic Surgery. This article is not intended to be an exhaustive treatise on the subject. Rather, it is designed to serve as a reference point for further in-depth study by review of the reference articles presented.

Focus session on the changing "epidemiology" of craniosynostosis (comparing two quinquennia: 1985-1989 and 2003-2007) and its impact on the daily clinical practice: a review from Necker Enfants Malades

INTRODUCTION

The aim of this study was to evaluate the evolution in craniosynostosis in terms of incidence and management in the last 20 years and to discuss the clinical implications and future perspectives with regards to the practical organization of daily practice.

METHODS

The relative incidence and management modalities of craniosynostosis hospitalized at the Craniofacial Unit of Necker, French National Referral Center for Faciocraniosynostosis, in two different quinquennia: 1985-1989 (group A) and 2003-2007 (group B) were reviewed.

RESULTS

A total of 1,286 children were included in our study; group A 472, group B 814, that is an overall increase of 1.7-fold in the second period of the study. Sagittal synostosis remained the most frequent type (45% of cases in both groups). Conversely, the number of cases of Pfeiffer syndrome increased from seven patients to 20 (x2.8) and metopic synostosis cases increased from 49 to 193 (x3.9). Mean age at surgery in group A was 22.5 months and 13 months in group B.

DISCUSSION

The comparison of the two quinquennia shows that there has been a change in the incidence of the different types of synostosis. The timing for surgery has also changed with the treatment of younger children in group B compared to group A. The principles of the surgical treatment of monosutural craniosynostosis have remained unmodified in our center. However, there has been an evolution in the techniques due to the introduction of new tools such as internal and external distractions, springs, and resorbable plates.

Calvarial remodelling for sagittal synostosis: does fibrin glue (Tisseel) reduce post-operative blood transfusion requirements?

INTRODUCTION

Calvarial remodelling for sagittal synostosis is extensive surgery and is associated with potential risks; the most significant of these is blood loss.

MATERIALS AND METHODS

We studied 16 patients undergoing calvarial remodelling by the same surgical team over a 12-month period to determine whether scalp closure with fibrin glue (Tisseel) could decrease post-operative bleeding and the need for blood transfusion. In the last 5 months of the period studied, fibrin glue (Tisseel) was used and six out of the 16 patients had their wound closure assisted by this means. Data was prospectively collected on age at surgery, the estimated peri-operative blood loss, the volume of blood transfused intra-operatively, the volume drained in the first 8 h post-operatively, the total post-operative drainage and the volume of any post-operative blood transfusion required.

RESULTS AND DISCUSSION

The two groups were comparable with a similar mean age at surgery, estimated peri-operative blood loss and intra-operative blood transfusion requirements. The volume drained in the first 8 h post-operatively was 172 ml in the treated group compared to 246 ml in the untreated group (p < 0.02) and the total post-operative drain volume was 301 ml compared to 441 ml (p < 0.01). None out of the six patients treated with fibrin glue required post-operative transfusion compared to two out of ten in the untreated group. The use of fibrin glue has enabled us to reduce post-operative bleeding and the need for post-operative blood transfusion.

Perioperative management of pediatric patients with craniosynostosis

Craniosynostosis, premature closures of the skull sutures, results in dysmorphic features if left untreated. Brain growth and cognitive development may also be impacted. Craniosynostosis repair is usually performed in young infants and has its perioperative challenges. This article provides background information about the different forms of craniosynostosis, with an overview of associated anomalies, genetic influences, and their connection with cognitive function. It also discusses the anesthetic considerations for perioperative management, including blood-loss management and strategies to reduce homologous blood transfusions.

Blood Conservation in Pediatric Anesthesia

This review focuses on perioperative blood conservation techniques and the role of transfusion triggers and algorithms, preoperative autologous donation, acute normovolemic hemodilution, intraoperative blood salvage, deliberate hypotension, and preoperative recombinant human erythropoietin in avoiding allogeneic blood transfusion in pediatric patients.

Blood sparing in craniosynostosis surgery

One of the main risks of craniosynostosis surgery is the possible need for an allogenic blood transfusion (ABT). Most patients are operated on in the first months of life, when physiological conditions are particularly sensitive to even limited blood losses. Furthermore, most surgical techniques proposed in the past were based on extensive craniectomies and cranial remodeling. Because of the known infective and immunologic risks of ABT, in recent years more attention has been dedicated to factors that might help reduce the risk of ABT. We review recent preoperative (ie, erythropoietin administration), intraoperative (ie, acute normovolemic hemodilution, intraoperative blood salvage), and postoperative (ie, clinical monitoring, postoperative blood salvage) anesthesiologic procedures developed with this aim in mind. We also consider operative techniques and technical apparatus that reduce surgical invasiveness, particularly preoperative planning, age selection, and the role of endoscopic assistance and gradual distraction devices.