Challenges in pediatric neuroanesthesia: awake craniotomy, intraoperative magnetic resonance imaging, and interventional neuroradiology

Pediatric neuroanesthesia experiences: A single center retrospective cohort study

Background/Aim: Pediatric neuroanesthesia is a special field that requires significant experience and infrastructure because of anatomical, neurological, and pharmacological differences in the pediatric patient population. Although technological improvements provide more effective and safer neuroanesthesiological management, the principles of neuroanesthesia, neurocognitive development, and the effects of anesthetic agents on central nervous system development are well-known. The majority of pediatric neuroanesthesia articles in the literature are reviews; however, retrospective/prospective case series and controlled research are limited. In this retrospective cohort study, we aimed to contribute to the existing literature by reviewing and analyzing our single-center 10-year experiences and results addressing pediatric neuroanesthesia management. Methods: After ethical committee approval, anesthetic and surgical reports from 1165 pediatric neurosurgical cases over ten years were collected. Demographic data, intra-operative vascular management, anesthesia techniques, airway management, patient positions, analgesia methods, and complications were evaluated in this retrospective cohort study. The available surgical intervention, patient positions, intra-operative neuromonitorization (IONM), and intra-operative magnetic resonance imaging (IOMR) records were also analyzed. Results: Six-hundred forty-six (55.4%) girls and 519 (44.5%) boys were included in the study. The median age was 60 (0–216) months. Cranial interventions were performed in 842 (72.3%) patients, and spinal interventions were performed in 323 (27.7%) patients. Patients’ American Society of Anesthesiologists (ASA) physical scales grouped as I, II, III, and IV were 718 (61.6%), 360 (30.9%), 82 (7%), and 5 (0.4%), respectively. Sevoflurane (40.3%), propofol (37.2%), and sodium thiopental (2.5%) were used for anesthetic induction. Neuromuscular block was performed with rocuronium (56.7%) and atracurium (14.4%). Neuromuscular blocking agents were not used in 337 patients (28.9%). A blood transfusion was required in 120 patients (10.3%), and 40% of these patients underwent surgery for craniosynostosis. Two-hundred twenty-two (19.1%) were monitored with IONM, and IOMR was carried out in 124 (10.6%) of the cases. The anesthesia-related complication rate was 5.15% (60 patients). Conclusion: Although pediatric neurosurgical interventions involve high risks, they are becoming increasingly common in our daily practice. Neuroanesthesiologists should know the procedures, techniques, and advances for safe and effective management of pediatric neurosurgical cases. We think that these data may be helpful as a guide for the anesthetic management of pediatric neurosurgical cases.

Awake brain surgery in children-a single-center experience

INTRODUCTION

Awake brain surgery (ABS) represents a rare surgical procedure in children as age and psychological aspects, which are considered to interfere with its feasibility and psychological outcome and limit its application. Only few pediatric case series have been reported so far, indicating a more complex translation of this surgical approach to children. However, the advances in neuropsychological testing and monitoring may have a substantial impact on ameliorating the eligibility of children undergoing awake procedures. This study addresses the condition of ABS in a pediatric cohort, focusing on its practicability and diversified outcome aspects.

METHODS

We performed a retrospective review and prospective outcome analysis of pediatric patients with CNS lesions undergoing ABS between 2005 and 2018, completed at the University of Lyon, France.

RESULTS

Eighteen children were considered for ABS with respect to the eloquent location of their CNS lesions documented in their pre-operative MRI. Seventeen of them underwent asleep-awake-asleep brain surgery. The cohort included 5 males and 12 females. The median age at surgery was 14.8 years, (range 9.4 to 17.6 years). Intraoperative testing included electrocortical stimulation while pursuing speech or motor activity. Most of the lesions were intrinsic tumors of glial origin. A complete tumor removal was achieved in 11 patients (65%). Post-operative neurological deficits were transiently observed in 2 patients, whereas severe psychological reactions occurred in 1 child. Persistent attention deficits were found in 2 patients. One patient experienced an infectious complication requiring antibiotic treatment. Two patients died during follow-up due to tumor progression. The mean duration of follow up was 22.2 months (range 3.4 to 46.8 months).

CONCLUSIONS

ABS was shown to be beneficial in terms of efficient tumor resection besides simultaneous preservation of neurological functions. Psychological preparation of the families and the children is essential to increase the number and age range of patients, who can benefit from this technique. Neuropsychological testing before and after surgery is essential to determine cognitive outcome, which can be altered in a minority of patients.

Feasibility of awake craniotomy in the pediatric population

BACKGROUND

Awake craniotomy with direct cortical stimulation and mapping is the gold standard for resection of lesions near eloquent brain areas, as it can maximize the extent of resection while minimizing the risk of neurological damage. In contrast to the adult population, only small series of awake craniotomies have been reported in children.

AIMS

The aim of our study is to establish the feasibility of awake craniotomy in the pediatric population.

METHODS

We performed a retrospective observational study of children undergoing a supratentorial awake craniotomy between January 2009 and April 2019 in a pediatric tertiary care center. Our primary outcome was feasibility of awake craniotomy, defined as the ability to complete the procedure without conversion to general anesthesia. Our secondary outcomes were the incidence of serious intraoperative complications and the mapping completion rate.

RESULTS

Thirty procedures were performed in 28 children: 12 females and 16 males. The median age was 14 years (range 7-17). The primary diagnosis was tumor (83.3%), epilepsy (13.3%), and arterio-venous malformation (3.3%). The anesthetic techniques were asleep-awake-asleep (96.7%) and conscious sedation (3.3%), all cases supplemented with scalp block and pin-site infiltration. Awake craniotomy was feasible in 29 cases (96.7%), one patient converted to general anesthesia due to agitation. Serious complications occurred in six patients: agitation (6.7%), seizures (3.3%), increased intracranial pressure (3.3%), respiratory depression (3.3%), and bradycardia (3.3%). All complications were quickly resolved and without major consequences. Cortical mapping was completed in 96.6% cases. New neurological deficits occurred in six patients (20%)-moderate in one case and mild in 5-being all absent at 6 months of follow-up.

CONCLUSION

Awake craniotomy with intraoperative mapping can be successfully performed in children. Adequate patient selection and close cooperation between neurosurgeons, anesthesiologists, neuropsychologists, and neurophysiologists is paramount. Further studies are needed to determine the best anesthetic technique in this population group.

Psychological aspects of awake brain surgery in children-interests and risks

Awake brain surgery (ABS) in children remains a subject of controversial debate for the potential psychological limitations that are related to this type of procedure. However, the tolerance and benefits of ABS in adults advocate for increased application of ABS in children. In this study, we report the psychological assessment, evaluation algorithm, and outcome of pediatric patients, who underwent ABS for surgical treatment of lesions in eloquent areas. Psychological selection criteria and the specifications of psychological support are described. A retrospective review and analysis of psychological assessment and psychological outcome of pediatric patients, who underwent ABS between 2005 and 2018 at the Department of pediatric neurosurgery, University of Lyon, France, was performed. Long-term psychological outcomes are reported. ABS was proposed to 18 children aged between 9 and 17 years and their families. After psychological evaluation of the individual patient and their familial surrounding, five boys and 12 girls (n = 17) were accounted eligible for ABS. They underwent asleep-awake-asleep brain surgery with intraoperative testing. In 16 cases, ABS could be performed as planned. Psychological alterations were postoperatively observed in 3 patients, symptoms of a post-traumatic stress disorder in 1 patient. The precise preoperative evaluation of the risk-benefit ratio in children plays a crucial role in anticipating a good psychological outcome. Professional psychological preparation and support of the child and his or her family are the key elements for successful completion of ABS.

Awake brain surgery in children-review of the literature and state-of-the-art

OBJECTIVE

Awake brain surgery (ABS) is poorly reported in children as it is considered having limited indications due to age and neuropsychological aspects interfering with its feasibility and psychological outcome. The aim of this article is to review the current state-of-the-art of ABS in children and to offer an objective summary of the published literature on diversified outcome aspects of pediatric awake procedures.

METHODS

A literature review was performed using the MEDLINE (PubMed) electronic database applying the following MeSH terms to the keyword search within titles and abstracts: "awake brain surgery children," "awake brain surgery pediatric," "awake craniotomy children," "awake craniotomy pediatric," and "awake surgery children." Of the initial 753 results obtained from these keyword searches, a full text screening of 51 publications was performed, ultimately resulting in 18 eligible articles for this review.

RESULTS

A total of 18 full text articles reporting the results of 50 patients were included in the analysis. Sixteen of the 18 studies were retrospective studies, comprising 7 case series, 9 case reports, and 2 reviews. Eleven studies were conducted from anesthesiological (25 patients) and 7 from neurosurgical (25 patients) departments. Most of the patients underwent ABS for supratentorial lesions (26 patients), followed by epilepsy surgery (16 patients) and deep brain stimulation (DBS) (8 patients). The median age was 15 years (range 8-17 years). Persistent deficits occurred in 6 patients, (12%), corresponding to minor motor palsies (4%) and neuropsychological concerns (8%). An awake procedure was aborted in 2 patients (4%) due to cooperation failure and anxiety, respectively.

CONCLUSIONS

Despite well-documented beneficial aspects, ABS remains mainly limited to adults. This review confirms a reliable tolerability of ABS in selected children; however, recommendations and guidelines for its standardized implementation in this patient group are pending. Recommendations and guidelines may address diagnostic workup and intra-operative handling besides criteria of eligibility, psychological preparation, and coordinated neuropsychological testing in order to routinely offer ABS to children.

Anesthetic challenges and outcomes for procedures in the intraoperative magnetic resonance imaging suite: A systematic review

BACKGROUND AND OBJECTIVE

Hybrid operating room suites with intraoperative magnetic resonance imaging enable image guided surgery in a fully functional operating room environment. While this environment creates challenges to anesthetic care, the effects on anesthetic adverse events and outcomes are largely unknown. This systematic scoping review aims to map the existing knowledge about anesthetic care in advanced imaging hybrid operating rooms.

METHODS

A broad-based literature search was performed using the PubMed (Medline), Embase, Cochrane Library, Web of Science, and Google Scholar databases. References published in English between January 1994 and August 2017 were included. Quality of evidence was assessed using the GRADE guidelines.

RESULTS

Forty-seven manuscripts were eligible for data collection. Adverse events were heterogeneously defined across 17 manuscripts and occurred in 0 to 100% (quality of evidence mostly very low). Monitoring difficulty was reported in 4 manuscripts of very low data quality. Interference between the magnet and the electrocardiogram was investigated in 2 manuscripts (quality of evidence low and very low, respectively). None of the reported events appeared to result in long-term patient harm. Author recommendations or a narrative review of the literature were provided in 40 manuscripts. Common safety concerns included lower equipment reliability, inaccessibility of the patient and airway, and the relative isolation of the suite (in relationship to other anesthesia care areas). Most authors also emphasized the importance of safety checklists, protocols, and provider training.

DISCUSSION

While intraoperative magnetic resonance imaging hybrid operating rooms are increasingly utilized, the existing literature does not allow estimating adverse event rates in this location. Prospective studies quantifying the effect of the environment on anesthesia outcomes are lacking. Despite this, there is a broad consensus regarding the anesthetic and safety concerns. More research is needed to inform practice standards and training requirements for this challenging environment.

Risk factors for post-operative respiratory failure among 94,621 neurosurgical patients from 2006 to 2013: a NSQIP analysis

INTRODUCTION

Post-operative respiratory failure can occur after neurosurgical operations. Identification of risk factors for respiratory failure after neurosurgery may help guide clinical decision-making, decrease length of stay, improve patient outcomes, and lower costs.

METHODS

We performed a search of the ACS-NSQIP database for all patients undergoing operations with a neurosurgeon from 2006 to 2013. We analyzed demographics, past medical history, and post-operative respiratory failure, defined as unplanned intubation and/or ventilator dependence for more than 48 h post-operatively.

RESULTS

Of 94,621 NSQIP-reported neurosurgical patients from 2006 to 2013, 2325 (2.5 %) developed post-operative respiratory failure. Of these patients, 1270 (54.6 %) were male, with an overall mean age of 60.59 years; 571 (24.56 %) were current smokers and 756 (32.52 %) were ventilator-dependent. Past medical history included dyspnea in 204 patients (8.8 %), COPD in 198 (8.5 %), and congestive heart failure in 66 (2.8 %). The rate of post-operative respiratory failure decreased from 4.1 % in 2006 to 2.1 % in 2013 (p < 0.001). Of the 2325 patients with respiratory failure, 1061 (45.6 %) underwent unplanned intubation post-operatively and 1900 (81.7 %) were ventilator-dependent for more than 48 h. The rate of both unplanned intubation (p < 0.001) and ventilator dependence (p < 0.001) decreased significantly from 2006 to 2013. Multivariate analysis demonstrated that significant risk factors for respiratory failure included inpatient status (p < 0.001, OR = 0.165), age (p < 0.001, OR = 1.014), diabetes (p = 0.001, OR = 1.489), functional dependence prior to surgery (p < 0.001, OR = 2.081), ventilator dependence (p < 0.001, OR = 10.304), hypertension requiring medication (p = 0.005, OR = 1.287), impaired sensorium (p < 0.001, OR = 2.054), CVA/stroke with or without neurological deficit (p < 0.001, OR = 2.662; p = 0.002, OR = 1.816), systemic sepsis (p < 0.001, OR = 1.916), prior operation within 30 days (p = 0.026, OR = 1.439), and operation type (cranial relative to spine, p < 0.001, OR = 4.344, Table 4).

CONCLUSIONS

Based on the NSQIP database, risk factors for respiratory failure after neurosurgery include pre-operative ventilator dependence, alcohol use, functional dependence prior to surgery, stroke, and recent operation. The overall rate of respiratory failure decreased from 4.1 % in 2006 to 2.1 % in 2013 according to these data.