Scoliosis in Children: Impact of Goal Directed Therapies on Intra-operative and Postoperative Outcomes


 Background: Scoliosis is among interventions with high postoperative complication rates due to the characteristics of the surgery, where blood loss, transfusion and fluid requirements can be increased.A monocentric retrospective observational study was undertaken earlier to determine predictors of intraoperative and postoperative outcomes in surgical patients. In this initial cohort, there were patients who underwent scoliosis surgery, and a secondary analysis to describe outcomes in these patients was realized and is presented here.Objective: To describe intraoperative and postoperative outcomes in patients under 18 years old in scoliosis surgery included in the initial study and to propose improvement implementation measures.Methods: Secondary analysis of patients undergoing scoliosis surgery. The study was approved by the Ethics Committee.Results: There were 116 patients with a mean age of 147.5 ± 40.2 months. Twenty-eight patients (24.1%) presented intraoperative and/or postoperative complications. The most common intraoperative complication was hemorrhagic shock in 3 patients (2.6%). The most common postoperative organ failure was neurologic in seven patients (6%), respiratory in 3 patients (2.6%), cardio-circulatory in 2 patients (1.7%) and renal failure in one patient (0.9%).The most common postoperative infection was surgical wound sepsis in 8 patients (6.9%), urinary sepsis in three patients (2.6%), and abdominal sepsis and septicemia in two patients (1.7%).twelve patients (10.3%) had reoperations.Fifty-six patients (48.3%) had intraoperative transfusion.There was no in-hospital mortality.Conclusion: Integrating goal-directed therapies in this surgical setting could improve postoperative outcomes.


Introduction
Scoliosis surgery is one of the most common performed major elective surgeries in our Hospital.
This disorder of the vertebral column is classi ed as idiopathic or juvenile and neuromuscular.
The etiopathology of juvenile scoliosis is unknown whereas neuromuscular scoliosis can be associated with neuromuscular diseases, bone diseases or other syndromes. Postoperative morbidity in scoliosis is high due to the characteristics of the surgery where blood losses, transfusion and uid therapy requirements can be increased (1). The patient global status is one of the predictors of postoperative evolution (2). There is growing evidence that applying enhanced recovery after surgery protocols in scoliosis surgery in children reduces postoperative morbidity in terms of organ dysfunction and length of hospital stay (LOS) (3). We conducted earlier in our Hospital a monocentric observational study in neurosurgical, abdominal surgical and orthopedic patients to determine predictors of intra-operative and postoperative outcomes (2). In this cohort of 594 patients there were patients who underwent scoliosis surgery. We aimed with this secondary analysis of the initial study to describe intraoperative and postoperative outcomes in patients who had scoliosis surgery and to implement improved intraoperative patient management protocols with the objectives of optimizing postoperative outcome in this surgical population.

Methods And Materials
Secondary analysis of patients who underwent scoliosis surgery included in the initial study (2). Inclusion criteria were patients included in the initial study aged less than 18 years old and who underwent scoliosis surgery.
Exclusion criteria were patients above 18 years old and who did not undergo scoliosis surgery included in the initial study.
Patients were included retrospectively from 1 January 2014 to 17 May 2017.
Statistics were analyzed with XLSTAT 2020.4.1. software. Continuous variables were expressed as medians with ranges or means with standard deviations. Categorial variables were described in proportions.
In our Hospital, scoliosis surgical patients are managed perioperatively according to a protocol described here. Preoperatively patients have respiratory functional tests, iron and erythropoietin supplementation, complete dental examination, nasal antibiotic therapy with mupirocin and a special ber free diet several days prior to surgery, complete blood cell count and packed red blood cells units available.
Intraoperatively 2 large peripheral intravenous lines and an arterial catheter are inserted; patients are monitored with bispectral index, indwelling bladder catheter, nasogastric tubing, central core temperature probe, uid warming system, warming blanket and somesthesia evoked potentials. Induction of anesthesia can be inhalational with sevo urane or intravenous with propofol, remifentanil and ketamine.
Maintenance of anesthesia is intravenous with propofol, remifentanil and ketamine. Airway is secured with orotracheal or nasotracheal intubation. Tranexamic acid is administered as an intravenous bolus of 30 mg/kg followed by an intravenous infusion of 10 mg/kg/h. A cell saver is available in case of neuromuscular scoliosis. Antibiotic prophylaxis is performed with cefazolin and or vancomycin depending on patient's microbiological status. Fluid therapy is performed with crystalloids as 10-20 ml/kg bolus and colloids (plasmion®) as 30 ml/kg bolus.
The objective is to maintain mean arterial pressure above 60 mmHg.
Postoperative analgesia is realized with spinal analgesia with morphine as 5µg/kg (maximum 500 µg) administered intraoperatively, acetaminophen, ketoprofen, clonidine and patient controlled analgesia with intravenous bolus morphine.
Patients are extubated in the operation room or in the recovery room. Table 1 illustrates the general characteristics Re-operation n (%) 12 ( Postoperative septicemia n (%) 2 (1.7)
The most common intraoperative complication was hemorrhagic shock in 3 patients (2.6%) followed by anaphylaxis and respiratory failure in one patient (0.9%) respectively. The most common postoperative organ failure was neurologic in seven patients (6%) followed by respiratory in 3 patients (2.6%), followed by cardio-circulatory in 2 patients (1.7%) and renal failure in one patient (0.9%).
The most common postoperative infection was surgical wound sepsis in eight patients (6.9%), followed by urinary sepsis in three patients (2.6%), followed by abdominal sepsis and septicemia in two patients (1.7%) respectively.
Fifty-six patients (48.3%) were intraoperatively transfused with packed red blood cells and or fresh frozen plasma and or platelet units.
There was no in-hospital mortality.   The most common co-morbidities were cerebral anoxic lesions in 22 patients (18.9%), followed by neuro bromatosis in 7 patients (6%), followed by myelomeningocele, osteogenesis imperfecta and polymalformative syndrome in 4 patients (3.5%) respectively, followed by congenital heart disease and psychomotor de ciency in 2 patients (2.5%) respectively.

Discussion
With regards to the rate of patients with intraoperative and or postoperative complications, including transfusion guided protocols with point of care tests, goal directed uid and hemodynamic therapy with validated tools and parameters in children and integrating enhanced recovery after surgery protocols to optimize intraoperative management in scoliosis surgery could improve postoperative outcome in this surgical setting (3,4,5,6,7,8,9,10,11,12,13,14,15).
To improve blood product administration practices in scoliosis surgery, transfusion guided protocols with point of care viscoelastic assays have to be included in this setting. Point of care tests in hemorrhagic interventions have been shown to reduce fresh frozen plasma administration and length of hospital stay in children (4). Algorithms with rotational thromboelastometry are illustrated in Figs. 1 to 3 to guide transfusion in hemorrhagic surgery (15). Intraoperative goal directed uid and hemodynamic therapy protocols with validated tools and parameters in children need to be included in intraoperative management in this surgical intervention to guide uid and vasoactive therapy. Monitoring mean blood pressure is not enough for optimal hemodynamic management. Fluid management is best assessed with aortic blood ow peak velocity variation with echocardiography or esophageal doppler probe (13). The limiting factor of echocardiography is expertise. Transthoracic echocardiography can be di cult to perform if the patient is in prone position which can limit access to the apex or the sternal notch and the solution can be either an esophageal doppler probe or transoesophageal echocardiography however the latter necessitates expertise. Flotrac/Vigileo has been shown to reduce blood product administration, uid requirements, postoperative pulmonary and gastrointestinal complications and length of intensive care unit stay in spine surgery (11). Stroke volume variation with Flotrac/Vigileo can be used for uid therapy.
With this device, stroke volume variation is determined with the arterial pressure waveform analysis however evidence in children with Flotrac/Vigileo on the impact of postoperative outcome are lacking (10,12). Studies in children with Flotrac/Vigileo are needed to clarify the impact on postoperative outcome.
Enhanced recovery after surgery protocols have been shown to decrease postoperative complications in scoliosis surgery in children, integrating these pathways in this surgical setting can improve postoperative evolution (3). Predictors of postoperative outcomes include patient's global status, type of surgery, emergency age and transfusion (14). Goal directed therapies are possible solutions for postoperative outcome improvement in critical ill children and in major pediatric surgery.

Conclusion
To upgrade postoperative outcome in pediatric scoliosis surgery, transfusion guided protocols with point of care tests, goal directed uid and hemodynamic therapy with validated tools and parameters in children and enhanced recovery after surgery need to be included in this surgical setting management.

Declarations
Con ict of Interest: The author declared no con icts of interest.