Test-enhanced learning in Neuroanesthesia for the First Year anesthetic residents: a randomized controlled trial.

BACKGROUND: Test enhancing learning (TEL) had shown a significant effect in promoting the learning of many learning contents. However, its effect on the postgraduate medical level was unclear. This study aimed to investigate the effect of TEL in 1st year anesthesiology residents learning neuroanesthesia. METHOD: The residents were randomized to either group A, which was assigned to do the intervention exam (exam A) for two times during learning in neuroanesthesia, or group B, which studied in the same environment without doing the exam. All participants were assigned to do the assessment exam (exam B) at one month after the end of the rotation. All of the exams were ten multiple choice questions (MCQ). Since the anesthesia residents rotated to neuroanesthesia for two weeks twice during the first year, we conducted the experiments twice, using exams that covered both basic science (BS) and clinical science (CS) topics. RESULTS: There was no significant difference in mean ± SD of the scores for assessment exams asking about the basic science topic (BS_B) [group A (5.25 ± 2.05) VS group B (4.90 ± 1.80); p = 0.570] and the clinical science topic (CS_B) [group A (6.30 ± 1.26) VS group B (5.95 ± 1.61); p = 0.448]. CONCLUSION: This study showed null findings on the effect of TEL on learning in residents of the first year of anesthesiology. More studies on TEL were required to confirm the effect of TEL and find the appropriate test format that could enhance learning for post-graduate medical trainees.

The Thalamus in Perioperative Neurocognitive Disorders.

Thalamus function and structure are known predictors of individual differences in the risk of age-related neurocognitive disorders (NCD), such as dementia. However, to date, little is known about their role in the perioperative setting. Here, we provide a narrative review of brain-imaging studies of preoperative and postoperative thalamus scanning parameters associated with risks of developing perioperative NCD, such as postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) during the postoperative phase. These findings are discussed in light of the concept of reserve capacity.

Co-administration of Ketamine in Pediatric Patients with Neurologic Conditions at Risk for Intracranial Hypertension.

BACKGROUND: Ketamine has traditionally been avoided as an induction agent for tracheal intubation in patients with neurologic conditions at risk for intracranial hypertension due to conflicting data in the literature. The objective of this study was to evaluate and compare the effects of ketamine versus other medications as the primary induction agent on peri-intubation neurologic, hemodynamic and respiratory associated events in pediatric patients with neurologic conditions at risk for intracranial hypertension. METHODS: This retrospective observational study enrolled patients < 18 years of age at risk for intracranial hypertension who were admitted to a quaternary children's hospital between 2015 and 2020. Associated events included neurologic, hemodynamic and respiratory outcomes comparing primary induction agents of ketamine versus non-ketamine for tracheal intubation. RESULTS: Of 143 children, 70 received ketamine as the primary induction agent prior to tracheal intubation. Subsequently after tracheal intubation, all the patients received adjunct analgesic and sedative medications (fentanyl, midazolam, and/or propofol) at doses that were inadequate to induce general anesthesia but would keep them comfortable for further diagnostic workup. There were no significant differences between associated neurologic events in the ketamine versus non-ketamine groups (p = 0.42). This included obtaining an emergent computed tomography scan (p = 0.28), an emergent trip to the operating room within 5 h of tracheal intubation (p = 0.6), and the need for hypertonic saline administration within 15 min of induction drug administration for tracheal intubation (p = 0.51). There were two patients who had clinical and imaging evidence of herniation, which was not more adversely affected by ketamine compared with other medications (p = 0.49). Of the 143 patients, 23 had pre-intubation and post-intubation intracranial pressure values recorded; 11 received ketamine, and 3 of these patients had intracranial hypertension that resolved or improved, whereas the remaining 8 children had intracranial pressure within the normal range that was not exacerbated by ketamine. There were no significant differences in overall associated hemodynamic or respiratory events during tracheal intubation and no 24-h mortality in either group. CONCLUSIONS: The administration of ketamine as the primary induction agent prior to tracheal intubation in combination with other agents after tracheal intubation in children at risk for intracranial hypertension was not associated with an increased risk of peri-intubation associated neurologic, hemodynamic or respiratory events compared with those who received other induction agents.

AIRWAY MANAGEMENT IN NEUROANESTHESIA.

Neurosurgical patients have specific airway management. Various conditions and diagnoses make intubation difficult and may also cause neurological damage. Spinal pathology, neurotrauma, cervical spine surgery, and pituitary gland surgery are just some examples. The aim of this review article is to present a broad spectrum of neurosurgical operations and potential complications in maintaining airway patency related to these issues. Quality perioperative preparation is a prerequisite to avoid the potentially irreversible consequences of difficult airways with a poor neurological or even fatal outcome. Patients with tumors of the pituitary region who present with Cushing's disease are prone to difficult ventilation, tracheal obstruction and difficult intubation. Awake craniotomy is also a challenge for the anesthesiologist, given that access to the airway is problematic due to the fixed frame. Unstable cervical spine occurs in cases of rheumatoid arthritis or blunt trauma, requiring precautions to be taken with spinal stabilization during intubation and induction. Pharyngeal edema and hematomas, possible complications of cervical spine surgery can endanger airway patency after extubation; postoperative patient supervision is thus required. Due to the potential threat to the patient's airway during neurosurgical procedures, quality anesthetic preoperative preparation is necessary to avoid irreversible damage and death.

A prospective observational single center study evaluating emergence agitation in the early postoperative period in adult patients undergoing elective craniotomies under general anesthesia.

Background and Aims: Emergence agitation is a significant clinical issue during recovery from general anesthesia. Patients after intracranial operations are even more vulnerable to the stress resulting from emergence agitation. Due to the limited data available in neurosurgical patients, we evaluated the incidence, risk factors, and complications of emergence agitation. Material and Methods: 317 consenting eligible patients undergoing elective craniotomies were recruited. The preoperative Glasgow Coma Scale (GCS)) and pain score were recorded. Bispectral Index (BIS) guided balanced general anesthesia was administered and reversed. Immediate postoperatively, the GCS and the pain score were noted. The patients were observed for 24 hours following extubation. The levels of agitation and sedation were evaluated by the Riker's Agitation-Sedation Scale. Emergence Agitation was defined as Riker's Agitation score of 5 to 7. Results: In our subset of the patient population, the incidence was 5.4%, mildly agitated in the first 24 hours and none required sedative medication as therapy. The sole risk factor identified was prolonged surgery beyond 4 hours. None of the patients in the agitated group had any complications. Conclusion: Early objective assessment of risk factors in the preoperative period with objective validated tests and shorter duration of surgery maybe the way forward in patients at high risk for emergence agitation, to reduce the incidence and mitigate the undesirable consequences.

Trans-nasal humidified rapid insufflation ventilatory exchange (THRIVE) in neuroanesthesia practice: A review.

Respiratory management is an important aspect of care in neuroanesthesia practice for neurosurgical patients. A wide variety of procedures are performed under sedation in the neurosurgical population, and maintaining oxygenation is of paramount importance during these procedures. The high-flow oxygen devices improve arterial oxygenation by providing higher inspiratory oxygen concentration and maintaining higher dynamic positive airway pressure. These devices have gained importance during the recent years with regard to enhancing patient safety. This narrative review focuses on the role of trans-nasal humidified rapid insufflation ventilatory exchange (THRIVE) and high-flow nasal oxygenation (HFNO) techniques in the neuroanesthesia practice and electroconvulsive therapy.

Full-text publications of presentations at neuroanesthesia meetings of India: A 5-year audit and analysis.

Backgroud and Aims: Conference presentations provide an opportunity to rapidly share findings of new research despite limitations of details and reach. Earlier studies have examined publication rates of conference presentations in anesthesia. However, conversion rate of neuroanesthesia meeting presentations to publications is unknown. We assessed the publication rate of neuroanesthesia conference presentations from India over a 5-year period and identified factors contributing to subsequent publications. Material and Methods: Conference abstracts of the Indian Society of Neuroanaesthesiology and Critical Care (ISNACC) from 2014 to 2018 were studied with regard to conversion to full-length publications. Details of presentations were obtained from abstracts published in the journal of ISNACC and details of publications were collected by searching Google and PubMed using title and author details. Results: Only 17.5% (40/229) of the abstracts presented at ISNACC conferences over a 5-year period resulted in subsequent full-text publications in peer-reviewed journals. Prospective cohort studies (OR [95% CI] 2.84 [1.05-8.56], P = 0.048), randomized trials (OR [95% CI] 2.69 [1.04 to 7.9], P = 0.053), and abstracts from public institutions (OR [95% CI] 3.44 [1.4 to 10.42], P = 0.014) were significantly associated with publications after conference presentations. Conclusion: The conversion rate of conference presentations of neuroanesthesia society of India into journal publications is significantly low. There is need for neuroanesthesia community of India to work together to improve the translation of presentations into publications.

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.

Anesthesia management for low-grade glioma awake surgery: a European Low-Grade Glioma Network survey.

BACKGROUND: Awake surgery has become a key treatment of diffuse low-grade gliomas (DLGG) and is divided in three main phases: opening, tumor resection - during which the patient needs to be fully awake - and closure. The anesthetic management of awake neurosurgery is a challenge, and there are currently no guidelines. OBJECTIVE: The objective of the survey was to explore differences and commonalities regarding the anesthetic management of awake DLGG surgery within the European Low-Grade Glioma Network (ELGGN) centers. METHODS: A form that contained 14 questions about the anesthetic management was sent to 28 centers in May 2015. RESULTS: Twenty centers responded. During the opening and closing non-awake periods, 56% of teams chose general anesthesia with mechanical ventilation for at least one period (asleep-awake-asleep, SAS protocol), and 44% monitored anesthesia care including sedation without mechanical ventilation (MAC protocol). In case of SAS, all the teams chose intravenous anesthesia, 82% used laryngeal mask instead of endotracheal intubation during the opening sequence, and 71% during closure. Local and regional anesthesia was practiced by all the teams. The most frequently reported cause of pain was dural and cerebral vessels manipulation (77%). Pain management was mostly based on paracetamol (70%) and remifentanil (55%). CONCLUSION: Our survey showed that there was an equivalent proportion of centers using SAS or MAC protocols in the anesthetic management of awake surgery in ELGGN centers. The advantages and disadvantages of each anesthesia protocol were reviewed.

Emergency neurological procedures during COVID-19 pandemic: Practical issues.

The novel coronavirus disease 2019 (COVID-19) has emerged as a global pandemic. A significant number of these patients would present to hospitals with neurological manifestations and neurosurgical emergencies requiring urgent treatment. The anesthesiologists should be prepared to manage these cases in an efficient and timely manner in the operating room, intensive care units, and interventional neuroradiology suites. The clinical course of the disease is in an evolving stage. As we acquire more knowledge about COVID-19, new recommendations and guidelines are being formulated and regularly updated. This article discusses the anesthetic management of urgent neurosurgical and neurointerventional procedures. In addition, a brief overview of intrahospital transport of neurologically injured patients has been addressed.

Awake craniotomy in a super obese patient using high flow nasal cannula oxygen therapy (HFNC).

Super obesity with a body mass index (BMI) >50 kg/m2 presents a challenge for the neuroanesthesiologist during awake craniotomy procedures and poses increased perioperative risk of complications, even vis-à-vis morbid obesity. This article presents a super obese patient (BMI 57 kg/m2) with drug-refractory epilepsy and obstructive sleep apnea who underwent left anterior temporal lobectomy through awake craniotomy to preserve language and memory, using warmed humidified high flow nasal cannula (HFNC) oxygen therapy. Awake craniotomy was facilitated by the use of HFNC, which proved essential to prevent airway collapse by creating continuous positive airway pressure through high flow and facilitated intraoperative neurologic language and memory testing while maintaining adequate oxygenation.

Radiographic comparison of cervical spine motion using LMA Fastrach, LMA CTrach, and the Macintosh laryngoscope

Background/aim/AIM: The optimal technique for airway management in patients with cervical pathology remains unclear. Intubating laryngeal mask airway devices such as LMA CTrach and LMA Fastrach have not been compared for cervical spine (C-spine) movements in the context of cervical pathology. The present study aimed to determine upper C-spine movements by radiography during intubation with different devices as well as comparing the duration and success of intubation in cervical surgery. Materials and methods: Sixty patients scheduled for elective cervical surgery were registered in this prospective, randomized study. Patients with cervical trauma/injury, previous neck surgery, and body mass index (BMI) of >35 kg/m2 were excluded. Participants were randomized to one of the 3 groups: LMA CTrach, LMA Fastrach, or the Macintosh laryngoscope. C-spine motion was evaluated by measuring angles created by bordering vertebrae at cervical 1/2 and 2/3 (C1/2, C2/3) segments on 2 lateral cervical radiographs for each patient. Intubation time, ease of intubation, number of attempts, and success rate were also documented. Results: Demographic data were similar in all the groups. The cervical movement with LMA CTrach and LMA Fastrach compared to the Macintosh laryngoscope were similar at C1/2. However, LMA CTrach significantly reduced extension compared to LMA Fastrach and Macintosh laryngoscopes at C2/3. Duration of intubation was significantly shorter with the Macintosh laryngoscope. The rate of successful intubation was 80% with LMA Fastrach and 100% with both LMA CTrach and the Macintosh laryngoscopes. Conclusion: The LMA CTrach laryngoscopy involves less upper C-spine movement than the LMA Fastrach and does not increase the duration of the intubation period.

Neuroanesthesia and pregnancy: Uncharted waters.

An incidence of 30-40 deaths per triennium in pregnant patients is reported because of brain pathology. Over the last two decades, the obstetric cause of mortality in the pregnant patient has declined, but the trend is rising for non-obstetric cause of mortality. Pregnancy is associated with a host of anatomical and physiological alterations that complicate the conduct of anesthesia. The brain is one of the vital organs of the body, and physiological changes during pregnancy alter the anesthesia management if associated with brain pathology. Malignant brain tumors and trauma remain a leading cause of indirect maternal mortality. Review of literature revealed paucity of evidence-based neuroanesthesia management for such patients. Navigating these uncharted waters remains a challenging exercise. With the lack of guidelines, the management is based largely on few case reports or case series.

[Modern principles of neurocritical care]. / Moderne Prinzipien der neurologischen Intensivmedizin.

Neurological diseases frequently demanding admittance to a dedicated neurological intensive care unit (neurocritical care) comprise space-occupying ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, traumatic brain injury, status epilepticus, bacterial meningitis, myasthenic crisis and Guillain-Barré syndrome. Due to often necessary analgesia, sedation and mechanical ventilation, neuromonitoring should ideally be employed. This consists of bedside invasive and non-invasive methods for monitoring cerebral perfusion, oxygenation, metabolism and neurophysiology. Modern treatment principles in neurocritical care mainly aim at avoiding or attenuating secondary neurological brain damage, in particular directed at sufficient perfusion and oxygenation. These include measures such as neuroprotective ventilation, stabilization of the circulation, decreasing intracranial pressure in brain edema and space-occupying processes, anticonvulsive treatment, temperature management and targeted disease-specific treatment.

Prevention and Treatment of Postoperative Pain after Lumbar Spine Procedures: A Systematic Review.

BACKGROUND AND OBJECTIVE: In the past 2 decades, in developed countries, spine procedures (surgical and percutaneous) had the highest absolute increase in case volume trend. The optimal approach to prevent and treat postoperative pain is continuously evolving. This systematic literature review presents evidence on safety and efficacy of pharmacological and nonpharmacological therapies to prevent and treat postoperative pain after lumbar spine procedures. DATABASES AND DATA TREATMENT: Publications listed in PUBMED and EMBASE were considered to identify randomized clinical trials suitable for inclusion in this systematic review. Key words for literature search were selected, with authors' agreement, using the PICOS approach (participants, interventions, comparisons, outcomes, and study design). RESULTS: Fifty-nine randomized clinical trials (involving a total of 4,238 patients, with ages ranging from 18 to 86 years) published between January 2012 and September 2017 were retrieved. Data are presented according to the timing of therapy administration. CONCLUSION AND RECOMMENDATIONS: Clinical evidence on perioperative pain management in patients undergoing spine procedures have significantly evolved after the review published in 2012. The aim of this systematic review was to report the latest evidence published. These include the preoperative use of dexamethasone, which was shown to be able to reduce pain at mobilization but not to reduce pain at rest or total morphine consumption; the use of gabapentinoids as part of a multimodal analgesic approach; and the safety and effectiveness of the intraoperative use of ketamine, dexketoprofen, and tramadol. Finally, electrical nerve stimulation is gaining interest and is potentially suitable for clinical needs.

How I do it: Awake craniotomy.

BACKGROUND: Awake craniotomy allows continuous assessment of a patient's clinical and neurological status during open brain surgery. This facilitates early detection of interference with eloquent cortex, and hence can allow a surgeon to maximize resection margins without compromising neurological function. METHODS: Awake craniotomy requires an effective scalp blockade, intraoperative assessment, and a carefully co-ordinated theatre team. A variety of clinical and electrophysiological techniques can be used to assess cortical function. CONCLUSIONS: Effective scalp blockade and awake craniotomy provides the opportunity to intraoperatively assess cortical function in the awake patient, thus providing an important neurosurgical option for lesions near eloquent cortex.

Effects of propofol or sevoflurane anesthesia induction on hemodynamics in patients undergoing fiberoptic intubation for cervical spine surgery: A randomized, controlled, clinical trial.

BACKGROUND AND AIMS: In patients undergoing surgery for cervical myelopathy, induction of general anesthesia can induce systemic arterial hypotension that may worsen spinal cord hypoperfusion and precipitate spinal injury. In this randomized, controlled, clinical trial study, we compared the hemodynamic changes related to anesthesia induction with intravenous (IV) propofol- and sevoflurane-based inhalational induction in patients undergoing fiberoptic intubation for cervical spine surgery. MATERIAL AND METHODS: A total of 72 patients were studied. Hemodynamic effects were assessed measuring mean arterial pressure (MAP), and the echocardiographic evaluation of the left ventricular function. A Student's t-test with Bonferroni correction or Chi-squared test was used, when appropriate, to assess differences in hemodynamic (extent of MAP drop and incidence of episodes of severe arterial hypotension) and other variables (occurrence and duration of episodes of apnea). RESULTS: Patients assigned to total IV anesthetic approach had a lower MAP, and more significant changes in cardiac function compared to those who received the inhalational approach (68.1 ± 9.3 mmHg vs. 75.5 ± 10.3 mmHg; 25% vs. 5.5%). CONCLUSION: Anesthesia induction with both propofol or sevoflurane is safe and effective. However, total IV anesthesia induction is associated with more pronounced MAP drop which can worsen spinal cord hypoperfusion.

Safety, feasibility and complications during resective pediatric epilepsy surgery: a retrospective analysis.

BACKGROUND: Resective epilepsy surgery is an established and effective method to reduce seizure burden in drug-resistant epilepsy. It was the objective of this study to assess intraoperative blood loss, transfusion requirements and the degree of hypothermia of pediatric epilepsy surgery in our center. METHODS: Patients were identified by our epilepsy surgery database, and data were collected via retrospective chart review over the past 25 years. Patients up to the age of 6 years were included, and patients with insufficient data were excluded. RESULTS: Forty-five patients with an age of 3.2 ± 1.6 (mean ± SD) years and a body weight of 17 [14; 21.5] kg (median [25%, 75% percentile]) were analysed. Duration of surgery was 3 h 49 min ± 53 min, which was accompanied by an intraoperative blood loss of 150 [90; 300] ml. This corresponded to 11.7 [5.2; 21.4] % of estimated total blood volume, ranging from 0 to 75%. A minimal haemoglobin count of 8.8 ± 1.4 g/dl was measured, which was substituted with erythrocyte concentrate (100 [0; 250] ml) in 23 patients. Body core temperature dropped from 36.0 ± 0.7°C at baseline to a minimum of 35.7 ± 0.7°C, and increased significantly (p < 0.001) thereafter to 37.1 ± 0.7°C until the end of surgery. A significant (p = 0.0003) correlation between duration of surgery and blood loss (Pearson r = 0.52) was observed. However, age, minimal body temperature or number of antiepileptic drugs seemed to have no impact on blood loss. CONCLUSION: Resective epilepsy surgery is a safe procedure even in the pediatric population, however it is associated with significant blood loss especially during long surgical procedures.

Principles of neuroanesthesia in aneurysmal subarachnoid hemorrhage.

Aneurysmal subarachnoid hemorrhage is associated with high mortality. Understanding of the underlying pathophysiology is important as early intervention can improve outcome. Increasing age, altered sensorium and poor Hunt and Hess grade are independent predictors of adverse outcome. Early operative interventions imposes an onus on anesthesiologists to provide brain relaxation. Coiling and clipping are the two treatment options with increasing trends toward coiling. Intraoperatively, tight control of blood pressure and adequate brain relaxation is desirable, so that accidental aneurysm rupture can be averted. Patients with poor grades tolerate higher blood pressures, but are prone to ischemia whereas patients with lower grades tolerate lower blood pressure, but are prone to aneurysm rupture if blood pressure increases. Patients with Hunt and Hess Grade I or II with uneventful intraoperative course are extubated in operation theater, whereas, higher grades are kept electively ventilated. Postoperative management includes attention toward fluid status and early management of vasospasm.

Intraoperative goal-directed fluid therapy in neurosurgical patients: A systematic review.

Background: Perioperative fluid management is critical in neurosurgery as over perfusion can lead to brain edema whereas under perfusion may lead to brain hypoperfusion or ischemia. We aimed to determine the effectiveness of intraoperative goal-directed fluid therapy (GDFT) in patients undergoing intracranial surgeries. Methods: We searched MEDLINE, Cochrane, and PubMed databases and forward-backward citations for studies published between database inception and February 22, 2024. Randomized controlled trials where intraoperative GDFT was performed in neurosurgery and compared to the conventional regime were included in the study. GDFT was compared with the conventional regime as per primary outcomes - total intraoperative fluid requirement, serum lactate, hemodynamics, brain relaxation, urine output, serum biochemistry, and secondary outcomes - intensive care unit and hospital length of stay. The quality of evidence was assessed with the Cochrane risk of bias tool. This study is registered on PROSPERO (CRD42024518816). Results: Of 75 records identified, eight were eligible, the majority of which had a low to moderate risk of overall bias. In four studies, more fluid was given in the control group. No difference in postoperative lactate values was noted in 50% of studies. In the remaining 50%, lactate was more in the control group. Three out of four studies did not find any significant difference in the incidence of intraoperative hypotension, and four out of six studies did not find a significant difference in vasopressor requirement. The majority of studies did not show significant differences in urine output, brain relaxation, and length of stay between both groups. None found any difference in acid base status or electrolyte levels. Conclusion: GDFT, when compared to the conventional regime in neurosurgery, showed that the total volume of fluids administered was lesser in the GDFT group with no increase in serum lactate. There was no difference in the hemodynamics, urine output, brain relaxation, urine output, length of stay, and biochemical parameters.