“Scalp Block” During Craniotomy: A Classic Technique Revisited

Scalp Nerve Block Alleviates Headaches Associated With Sonication During Transcranial Magnetic Resonance-Guided Focused Ultrasound

BACKGROUND AND OBJECTIVES

In magnetic resonance-guided focused ultrasound (MRgFUS) procedures, headache is a frequent symptom and cause of treatment discontinuation. Herein, we assessed the efficacy of scalp nerve block (SNB) for alleviating headache during MRgFUS procedures.

METHODS

The effect of SNB on intraprocedural headache was examined by retrospectively comparing 2 patient cohorts at a single institution. During the study period from April 2020 to February 2022, an SNB protocol for all patients with a skull density ratio ≤0.55 was instituted on October 6, 2021. The number of patients with a skull density ratio ≤0.55 was 34 before the protocol and 36 afterward. Headache intensity was evaluated using a numerical rating scale (NRS) after each sonication. To evaluate the effect of SNB on headache intensity, multiple regression analysis was performed per patient and per sonication. In the per-patient analysis, the effect of SNB was evaluated using the maximum NRS, mean NRS, and NRS at the first ultrasound exposure that reached 52.5°C. In the per-sonication analysis, the effect of SNB was evaluated not only for the entire sonication but also for sonications classified into ≤9999 J, 10 000 to 29 999 J, and ≥30 000 J energy doses.

RESULTS

With SNB, headache alleviation was observed in the NRS after the first sonication that reached 52.5°C in each patient (β = -2.40, 95% CI -4.05 to -0.758, P = .00499), in the NRS when all sonications were evaluated (β = -0.647, 95% CI -1.19 to -0.106, P = .0201), and in the NRS when all sonications were classified into 10 000 to 29 999 J (β = -1.83, 95% CI -3.17 to -0.485, P = .00889).

CONCLUSION

SNB significantly reduced headache intensity during MRgFUS, especially that caused by sonication with a moderate-energy dose. These findings suggest that scalp nerves play a role in headache mechanisms during MRgFUS.

Neural assemblies coordinated by cortical waves are associated with waking and hallucinatory brain states

The relationship between sensory stimuli and perceptions is brain-state dependent: in wakefulness, suprathreshold stimuli evoke perceptions; under anesthesia, perceptions are abolished; and during dreaming and in dissociated states, percepts are internally generated. Here, we exploit this state dependence to identify brain activity associated with internally generated or stimulus-evoked perceptions. In awake mice, visual stimuli phase reset spontaneous cortical waves to elicit 3-6 Hz feedback traveling waves. These stimulus-evoked waves traverse the cortex and entrain visual and parietal neurons. Under anesthesia as well as during ketamine-induced dissociation, visual stimuli do not disrupt spontaneous waves. Uniquely, in the dissociated state, spontaneous waves traverse the cortex caudally and entrain visual and parietal neurons, akin to stimulus-evoked waves in wakefulness. Thus, coordinated neuronal assemblies orchestrated by traveling cortical waves emerge in states in which perception can manifest. The awake state is privileged in that this coordination is reliably elicited by external visual stimuli.

Regional Anesthesia Techniques in Modern Neuroanesthesia Practice: A Narrative Review of the Clinical Evidence

Neurosurgical procedures are often associated with significant postoperative pain that is both underrecognized and undertreated. Given the potentially undesirable side effects associated with general anesthesia and with various pharmacological analgesic regimens, regional anesthetic techniques have gained in popularity as alternatives for providing both anesthesia and analgesia for the neurosurgical patient. The aim of this narrative review is to present an overview of the regional techniques that have been incorporated and continue to be incorporated into modern neuroanesthesia practice, presenting in a comprehensive way the evidence, where available, in support of such practice for the neurosurgical patient.

Ultrasound-guided Greater Occipital Nerve Block in Children Undergoing Posterior Fossa Craniotomy: A Randomized, Controlled Trial

BACKGROUND

Posterior fossa surgery is commonly associated with severe postoperative pain. This study assessed the impact of ultrasound-guided greater occipital nerve (GON) block on postoperative pain and hemodynamic profiles in pediatric posterior fossa craniotomy.

MATERIALS AND METHODS

Children aged 2 to 12 years undergoing elective posterior fossa craniotomy with general anesthesia were randomly allocated to a control group receiving standard care (n=18) or a GON block group receiving standard care plus bilateral ultrasound-guided GON block (=17). Outcomes were postoperative pain assessed using the objective pain scale, time to first postoperative analgesia, intraoperative fentanyl consumption, perioperative blood pressure and heart rate, incidence of nausea and vomiting, and nerve-block-related complications.

RESULTS

Objective pain scale scores were lower in the GON block group than in the control group at 2, 4, 6, 8 (all P =0.0001), 12 ( P =0.001), 16 ( P =0.03), and 24-hour ( P =0.004) postoperatively. The time to first analgesic request was 13.4±7.4 hours in the GON block group and 1.8±1.5 hours in the control group ( P <0.001). Intraoperative fentanyl consumption was 2.68±0.53 μg/kg -1 in the GON block group and 4.1±0.53 μg/kg -1 in the control group ( P =0.0001). Systolic blood pressure was lower in the GON block group at several intraoperative and postoperative time points, whereas heart rate was similar in the two groups at most time points. The incidence of postoperative nausea and vomiting was similar between groups ( P =0.38), and there were no nerve-block-related complications.

CONCLUSIONS

In children undergoing posterior fossa craniotomy, GON block was associated with superior quality and duration of postoperative analgesia and better hemodynamic profile compared with standard care.

Systemic and local immunosuppression in glioblastoma and its prognostic significance

The effectiveness of tumor therapy, especially immunotherapy and oncolytic virotherapy, critically depends on the activity of the host immune cells. However, various local and systemic mechanisms of immunosuppression operate in cancer patients. Tumor-associated immunosuppression involves deregulation of many components of immunity, including a decrease in the number of T lymphocytes (lymphopenia), an increase in the levels or ratios of circulating and tumor-infiltrating immunosuppressive subsets [e.g., macrophages, microglia, myeloid-derived suppressor cells (MDSCs), and regulatory T cells (Tregs)], as well as defective functions of subsets of antigen-presenting, helper and effector immune cell due to altered expression of various soluble and membrane proteins (receptors, costimulatory molecules, and cytokines). In this review, we specifically focus on data from patients with glioblastoma/glioma before standard chemoradiotherapy. We discuss glioblastoma-related immunosuppression at baseline and the prognostic significance of different subsets of circulating and tumor-infiltrating immune cells (lymphocytes, CD4+ and CD8+ T cells, Tregs, natural killer (NK) cells, neutrophils, macrophages, MDSCs, and dendritic cells), including neutrophil-to-lymphocyte ratio (NLR), focus on the immune landscape and prognostic significance of isocitrate dehydrogenase (IDH)-mutant gliomas, proneural, classical and mesenchymal molecular subtypes, and highlight the features of immune surveillance in the brain. All attempts to identify a reliable prognostic immune marker in glioblastoma tissue have led to contradictory results, which can be explained, among other things, by the unprecedented level of spatial heterogeneity of the immune infiltrate and the significant phenotypic diversity and (dys)functional states of immune subpopulations. High NLR is one of the most repeatedly confirmed independent prognostic factors for shorter overall survival in patients with glioblastoma and carcinoma, and its combination with other markers of the immune response or systemic inflammation significantly improves the accuracy of prediction; however, more prospective studies are needed to confirm the prognostic/predictive power of NLR. We call for the inclusion of dynamic assessment of NLR and other blood inflammatory markers (e.g., absolute/total lymphocyte count, platelet-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, systemic immune-inflammation index, and systemic immune response index) in all neuro-oncology studies for rigorous evaluation and comparison of their individual and combinatorial prognostic/predictive significance and relative superiority.

Closed reduction of fracture-dislocation of the sub-axial cervical spine with Gardner-Wells tongs. Technical note

Study design

Technical note.

Purpose

To provide a technical description of the placement of Gardner-Wells tongs and the performance of awake cranio-cervical traction to reduce AO type C injuries of the sub-axial cervical spine with Gardner-Wells tongs.

Methods

In this technical note, the authors present the indications, the contraindications, the pull-out of the pins, a detailed description of the technique for its proper placement, traction reduction technique, reduction maneuvers, complications and post-reduction care.

Results

Awake reduction of AO type C injuries of the sub-axial cervical spine can be successfully performed using Gardner-Wells tongs.

Conclusions

There is sufficient evidence to recommend the use of cranio-cervical traction in these vertebral injuries; however, we lack a detailed technical note to guide its proper placement.

The AANS Harvey Cushing Medal: a demographic and academic analysis of its recipients

Background

The Harvey Cushing Medal, awarded by the American Association of Neurological Surgeons, is the premier accolade in neurosurgery. The study's purpose was to examine the qualities and accomplishments of previous winners, emphasizing potential selection biases, with the aim to promote social justice and guide young neurosurgeons in their career paths.

Results

Predominantly, recipients graduated from top-ranked United States News and World Report institutions and specialized in cerebrovascular and neuro-oncologic/skull base neurosurgery. A significant proportion held roles as department or division chairs and led neurosurgical organizations. All awardees were male, and there was a notable trend of increasing publication counts among more recent recipients.

Conclusions

Commonalities among Harvey Cushing Medal winners include graduating from top institutions, holding significant leadership roles, and having an extensive publication history. However, the absence of female and underrepresented minority awardees underscores an urgent need for greater diversity in the selection process.

Effects of Scalp Nerve Block on the Quality of Recovery after Minicraniotomy for Clipping of Unruptured Intracranial Aneurysms : A Randomized Controlled Trial

OBJECTIVE

This study compared the quality of recovery (QoR) after minicraniotomy for clipping of unruptured intracranial aneurysms (UIAs) between patients with and without scalp nerve block (SNB).

METHODS

Patients were randomly assigned to the SNB (SNB using ropivacaine with epinephrine, n=27) and control (SNB using normal saline, n=25) groups. SNB was performed at the end of surgery. To assess postoperative QoR, the QoR-40, a patient-reported questionnaire, was used. The QoR-40 scores were measured preoperatively, 1-3 days postoperatively, at hospital discharge, and 1 month postoperatively. Pain and intravenous patient-controlled analgesia (IV-PCA) consumption were evaluated 3, 6, 9, and 12 hours and 1-3 days postoperatively.

RESULTS

All QoR-40 scores, including those measured 1 day postoperatively (primary outcome measure; 155.0 [141.0-176.0] vs. 161.0 [140.5-179.5], p=0.464), did not significantly differ between the SNB and control groups. The SNB group had significantly less severe pain 3 (numeric rating scale [NRS]; 3.0 [2.0-4.0] vs. 5.0 [3.5-5.5], p=0.029), 9 (NRS; 3.0 [2.0-4.0] vs. 4.0 [3.0-5.0], p=0.048), and 12 (NRS; 3.0 [2.0-4.0] vs. 4.0 [3.0-5.0], p=0.035) hours postoperatively. The total amount of IV-PCA consumed was significantly less 3 hours postoperatively in the SNB group (2.0 [1.0-4.0] vs. 4.0 [2.0-5.0] mL, p=0.044).

CONCLUSION

After minicraniotomy for clipping of UIAs, SNB reduced pain and IV-PCA consumption in the early postoperative period but did not improve the QoR-40 scores.

Scalp Nerve Block, Local Anesthetic Infiltration, and Postoperative Pain After Craniotomy: A Systematic Review and Network Meta-analysis of Randomized Trials

The most efficacious methods for controlling postoperative pain in craniotomy remain unknown. A systematic review and network meta-analysis were performed to compare the efficacies of different strategies of scalp nerve block (SNB), scalp infiltration (SI), and control in patients undergoing craniotomy. MEDLINE, Embase, and CENTRAL databases were searched for randomized controlled trials. The primary outcome was postoperative 24-hour pain score, and the secondary outcome was opioid consumption within the first 24 hour after surgery. The effect was estimated using the between-group mean difference and ranked using the surface under the cumulative ranking curve (SUCRA) score. Twenty-four randomized trials were identified for inclusion. SNB using ropivacaine reduced postoperative 24-hour pain score when compared with control (mean difference [95% credible interval], -2.04 [-3.13, -0.94]; low quality), and when compared with SI using ropivacaine (-1.77 [-3.04, -0.51]; low quality) or bupivacaine (-1.96 [-3.65, -0.22]; low quality). SNB using ropivacaine was likely the most efficacious method for pain control (SUCRA, 91%), and also reduced opioid consumption within the first postoperative 24 hours as compared with control (mean difference [95% credible interval], -11.91 [-22.42, -1.4]; low quality). SNB using bupivacaine, lidocaine, and epinephrine combined, and SNB using ropivacaine, were likely the most efficacious methods for opioid consumption reduction (SUCRA, 88% and 80%, respectively). In summary, different methods of SNB / SI seem to have different efficacies after craniotomy. SNB using ropivacaine may be superior to other methods for postcraniotomy pain control; however, the overall quality of evidence was low.

Anesthetic Management for Awake Craniotomy Applied to Neurosurgery

Our anesthetic technique proposed for awake craniotomy is the monitored anesthesia care (MAC) technique, with the patient in sedation throughout the intervention. Our protocol involves analgo-sedation through the administration of dexmedetomidine and remifentanil in a continuous intravenous infusion, allowing the patient to be sedated and in comfort, but contactable and spontaneously breathing. Pre-surgery, the patient is pre-medicated with intramuscular clonidine (2 µg/kg); it acts both as an anxiolytic and as an adjuvant in pain management and improves hemodynamic stability. In the operating setting, dexmedetomidine in infusion and remifentanil in target controlled infusion (TCI) for effect are started. The purpose of the association is to exploit the pharmacodynamics of dexmedetomidine which guarantees the control of respiratory drive, and the pharmacokinetics of remifentanil characterized by insensitivity to the drug. Post-operative management: at the end of the surgical procedure, the infusion of drugs was suspended. Wake-up craniotomy is associated with reduced hospital costs compared to craniotomy performed in general anesthesia, mainly due to reduced costs in the operating room and shorter hospital stays. Greater patient satisfaction and the benefits of avoiding hospital stay have led to the evolution of outpatient intracranial neurosurgery.

Systematic Review and Meta-Analysis of Randomized Controlled Trials for Scalp Block in Craniotomy

BACKGROUND

Scalp block is regional anesthetic injection along nerves innervating the cranium. Scalp blocks for craniotomy may decrease postoperative pain and opioid consumption. Benefits may extend beyond the anesthetic period.

OBJECTIVE

To analyze evidence for scalp block on postoperative pain and opioid use.

METHODS

This systematic review and meta-analysis, Prospective Register of Systematic Reviews registration (CRD42022308048), included Ovid Medical Literature Analysis and Retrieval System Online, Embase, and Cochrane Central Register of Controlled Trials inception through February 9, 2022. Only randomized controlled trials were included. We excluded studies not reporting either main outcome. Duplicate reviewers performed study selection, risk of bias assessment, data extraction, and evidence certainty Grading of Recommendations Assessment, Development, and Evaluation appraisal. Main outcomes were postoperative pain by visual analog scale within 72 hours and opioid consumption as morphine milligram equivalent (MME) within 48 hours.

RESULTS

Screening filtered 955 studies to 23 trials containing 1532 patients. Risk of bias was overall low. Scalp block reduced postoperative pain at 2 through 72 hours, visual analog scale mean differences of 0.79 to 1.40. Opioid requirements were reduced at 24 hours by 16.52 MME and 48 hours by 15.63 MME.

CONCLUSION

Scalp block reduces postoperative pain at 2 through 48 hours and may reduce pain at 72 hours. Scalp block likely reduces opioid consumption within 24 hours and may reduce opioid consumption to 48 hours. The clinical utility of these differences should be interpreted within the context of modest absolute reductions, overall care optimization, and patient populations. This is the first level 1A evidence to evaluate scalp block efficacy in craniotomy.

The Efficacy of Scalp Nerve Block in Postoperative Pain Management after Microvascular Decompression: A Randomized Clinical Trial

The scalp nerve block, created by injecting local anesthetics around the scalp nerves, is reported to effectively reduce pain after surgery. In this study, we evaluated the efficacy of scalp nerve block in patients with hemifacial spasm (HFS) undergoing microvascular decompression (MVD). Seventy-four patients who underwent MVD for HFS were enrolled. The block group received scalp nerve block with 0.5% ropivacaine before surgery. The primary outcome was cumulative dose of rescue analgesics 24 h postoperatively. The secondary outcomes were included pain scores, postoperative antiemetic consumption, and Quality of Recovery-15 scale. The cumulative dose of rescue analgesics at 24 h postoperatively was not significantly different between the two groups (4.80 ± 3.64 mg vs. 5.92 ± 3.95 mg, p = 0.633). However, the pain score was significantly reduced in the block group at 6, 12, and 24 h postoperatively. Postoperative antiemetic consumption was lower in the block group than the control group at 12 h. There were no significant differences between the two groups for other secondary outcomes. In MVD for HFS, a preoperative scalp nerve block might reduce postoperative pain in the early postoperative period, but a larger study using a multimodal approach is needed to confirm the efficacy of a scalp block.

Neural assemblies coordinated by cortical waves are associated with waking and hallucinatory brain states

The relationship between sensory stimuli and perceptions is brain-state dependent: in wakefulness stimuli evoke perceptions; under anesthesia perceptions are abolished; during dreaming and in dissociated states, percepts are internally generated. Here, we exploit this state dependence to identify brain activity associated with internally generated or stimulus-evoked perception. In awake mice, visual stimuli phase reset spontaneous cortical waves to elicit 3-6 Hz feedback traveling waves. These stimulus-evoked waves traverse the cortex and entrain visual and parietal neurons. Under anesthesia and during ketamine-induced dissociation, visual stimuli do not disrupt spontaneous waves. Uniquely in the dissociated state, spontaneous waves traverse the cortex caudally and entrain visual and parietal neurons, akin to stimulus-evoked waves in wakefulness. Thus, coordinated neuronal assemblies orchestrated by traveling cortical waves emerge in states in which perception can manifest. The awake state is privileged in that this coordination is elicited by specifically by external visual stimuli.

Evaluating the Anatomic Spread of Selective Nerve Scalp Blocks Using Methylene Blue: A Cadaveric Analysis

BACKGROUND

The modern scalp block consists of local anesthesia injections that target the supraorbital, supratrochlear, zygomaticotemporal, auriculotemporal, and greater and lesser occipital nerves. Limited data exist on the local anesthetic spread that occurs with this technique. This study examines the extent of the spread of a scalp block using methylene blue in a cadaveric model.

METHODS

A traditional landmark-based scalp block was performed on 6 unembalmed human cadavers using 25-G, 1.5-inch needles to inject 1 to 2 mL of methylene blue 0.1% at each nerve bilaterally; a total volume of 20 mL was injected. The cadavers were then dissected, and the spread of injectate was measured and recorded.

RESULTS

All the nerves required for analgesic coverage were appropriately stained by the injections, except for in 2 specimens where the lesser occipital nerve could not be identified. The zygomatic (stained in 2 of 8 specimens) and temporal (stained in 5 of 8 specimens) branches of the facial nerve were stained as a result of the zygomaticotemporal and/or auriculotemporal injections. Tracking from the zygomatic injection site was noted as far inferior as the temporalis muscle attachments on the mandible.

CONCLUSIONS

This cadaveric study confirms that the landmark-based technique for scalp blocks consistently stained all 6 nerves involved in scalp innervation. There was significant unintentional spread to the branches of the facial nerve when using the landmark technique.

Monitored Anesthesia Care Protocol for Awake Craniotomy and Patient's Perspective on the Procedure

OBJECTIVE

There is ongoing discussion on pros and cons in terms of different anesthesia protocols for awake craniotomy (AC) with direct brain stimulation. The aim of this study is to share our anesthesia protocol and present our patients' perspectives.

METHODS

We conducted an analysis of prospectively collected data from 53 (54 procedures) consecutive patients. Most of the patients (50) underwent surgery due to primary brain lesions. Eight procedures were performed in patients with lesions in the nondominant hemisphere for language. Four of all procedures were reoperations, and one patient was operated on in awake conditions twice. The psychological evaluation of patients was performed 2 times: 2 days before and after surgery. A visual analog scale for pain and stress levels as well as structured interviews was used.

RESULTS

Most patients tolerated ACwell. Patients reported that discomfort was mostly related to urinary catheter insertion, head holder placement, and temporal muscle detachment in cases of frontotemporal craniotomies. The intensity of stress measured with the visual analog scale before surgery was negatively associated with age and positively correlated with stress experienced in the operating room. In all patients, we were able to finish the procedure according to the monitored anesthesia care protocol without the need for conversion to general anesthesia. We observed 3 (5.6%) intraoperative seizures that required deepening of sedation.

CONCLUSION

AC using the monitored anesthesia care protocol was a safe and well-tolerated procedure with satisfactory patient experience. Extensive preoperative preparation should be considered a key part of the procedure.

Neurosurgical Anesthesia: Optimizing Outcomes with Agent Selection

Anesthesia in neurosurgery embodies a vital element in the development of neurosurgical intervention. This undisputed interest has offered surgeons and anesthesiologists an array of anesthetic selections to utilize, though with this allowance comes the equally essential requirement of implementing a maximally appropriate agent. To date, there remains a lack of consensus and official guidance on optimizing anesthetic choice based on operating priorities including hemodynamic parameters (e.g., CPP, ICP, MAP) in addition to the route of procedure and pathology. In this review, the authors detail the development of neuroanesthesia, summarize the advantages and drawbacks of various anesthetic classes and agents, while lastly cohesively organizing the current literature of randomized trials on neuroanesthesia across various procedures.

The effectiveness of scalp nerve block on hemodynamic response in craniotomy: a systematic review and meta-analysis of randomized trials

INTRODUCTION

Strategies that blunt noxious stimuli and stabilize hemodynamics may reduce perioperative cardiovascular complications and enhance recovery after craniotomy.

EVIDENCE ACQUISITION

Our systematic literature review and meta-analysis investigated whether scalp nerve block (SNB) reduces the acute hemodynamic response compared with non-SNB (scalp infiltration or control) in adult patients undergoing elective craniotomy. We searched MEDLINE, EMBASE, CENTRAL, and two Chinese databases for randomized trials. Primary outcomes included mean arterial pressure and heart rate during skull pin insertion and surgical incision in craniotomy. Secondary outcomes included incidence of hypertension and dosage of intraoperative analgesic opioids used. Random-effects models were used for meta-analyses.

EVIDENCE SYNTHESIS

SNB significantly reduced the mean arterial pressure (mean difference: -14.00 mmHg; 95% confidence interval [CI]: -19.71 to -8.28) and heart rate (mean difference: -11.55 beat/min; 95% CI: -19.31 to -3.80), when compared with non-SNB during skull pin insertion. A similar trend was observed during skin incisions (SNB vs. non-SNB, mean difference in mean arterial pressure: -9.46 mmHg; 95% CI: -14.53 to -4.38; mean difference in heart rate: -9.34 beat/min; 95% CI: -15.40 to -3.28). Subgroup analysis showed that, compared with scalp infiltration, SNB reduced mean arterial pressure and heart during pin insertion but not during skin incisions. SNB also reduced the incidence of intraoperative hypertension, but no difference was observed in intraoperative opioid consumption when compared with non-SNB.

CONCLUSIONS

SNB alleviated the craniotomy-associated hemodynamic response. SNB may be superior to scalp infiltration in maintaining hemodynamic stability during pin insertion. However, high-quality trials are still needed to provide more conclusive evidence.

Opioid-Free Anesthesia for Craniotomy

BACKGROUND

Perioperative opioids are problematic following craniotomy as they can impede neurological examination because of excessive sedation and mask surgical complications. Multimodal anesthetic techniques including nerve blocks have been used successfully to deliver opioid-free anesthesia in other surgical populations; however, no clinical data evaluating opioid-free anesthesia for craniotomy exists within the current body of literature.

MATERIALS AND METHODS

Six prospectively identified patients underwent supratentorial craniotomy at Emory University Hospital using a multimodal opioid-free anesthetic (OFA) technique consisting of preoperative scalp block, dexmedetomidine and intravenous acetaminophen. These opioid-free patients were matched by age, sex, incision length, and incision location to 18 retrospectively identified control patients who underwent craniotomy using conventional, opioid-based anesthetic techniques. Postoperative opioid consumption and pain scores were compared and analyzed for noninferiority.

RESULTS

Noninferiority of the OFA technique was demonstrated for opioid consumption at all measured intervals from postanesthesia care unit arrival to 24 hours postoperatively. Noninferiority was also demonstrated with respect to average postoperative pain scores from 0 to 12 hours, 0 to 24 hours, as well as length of postanesthesia care unit stay. Noninferiority was not shown for time to first rescue opioid postoperatively, pain scores for the 12 to 24 hours postoperative period, or time to emergence from anesthesia.

CONCLUSIONS

This pilot study demonstrates the feasibility of an OFA technique for patients undergoing supratentorial craniotomy and suggests that larger prospective randomized controlled trials are indicated to examine the role of multimodal anesthetic techniques for craniotomy.

Anatomical considerations of cutaneous nerves of scalp for an effective anesthetic blockade for procedures on the scalp

Objective

The anatomy of the scalp nerves varies widely with age, race, and individuals of the same race and even within the same individual and hence need to be studied extensively to avoid complications and improve effectiveness during various surgical and anesthetic procedures of the scalp.

Materials and Methods

Gross dissection was carried out on 11 cadavers (22 Hemifaces: 11 right and 11 left) with no obvious scalp deformities or surgeries. The distances of the supraorbital nerve (SON), supratrochlear nerve (STN), and greater occipital nerve (GON) from commonly used bony landmarks were measured. The branching pattern and presence of accessory notches/foramina were noted.

Results

SON and STN were found almost midway and at the junction between medial and middle one-third of the line joining midline and lateral orbital margin, respectively. The distances of STN and SON from the midline were about ½ and 3/4th of the transverse orbital diameters of the individual. GON was found at the medial 2/5 and lateral 3/5 of the line joining inion to the mastoid. In 40.9% cases, SON gave three branches while STN and GON remained as single trunks in 77.27% and 40.0% cases, respectively. Accessory foramina/notches for SON and STN were found in 36.36% and 4.54% of the specimen, respectively. SON and STN remained lateral in the majority while GON ran medially to corresponding vessels.

Conclusion

These parameters on the Indian population would give a comprehensive idea of the distribution of these cutaneous scalp nerves and would be beneficial in the targeted and accurate deposition of local anesthetic.

Ventriculoatrial Shunt Under Locoregional Anesthesia: A Technical Note

BACKGROUND

Ventriculoatrial shunt is routinely performed under general anesthesia and is used to treat various kinds of hydrocephalus. Idiopathic normal pressure hydrocephalus patients are generally elderly and can have high comorbidities; in such patients, avoiding general anesthesia and limiting opioid administration could be beneficial. We started to perform ventriculoatrial shunt under locoregional anesthesia, in order to make this procedure more truly "minimally invasive".

METHODS

Demographic data, American Society of Anesthesiologists (ASA) score and vital signs, Ramsay sedation scale, and procedural duration were collected. All procedures were performed combining sedation with cervical plexus and scalp block. After internal jugular vein cannulation, a catheter was inserted and connected with a programmable valve and then with the ventricular catheter. Outcome was assessed by the Idiopathic Normal Pressure Hydrocephalus Grading Scale and complications were recorded at 3-month follow-up.

RESULTS

Ten consecutive patients were enrolled; the mean age was 74 years, 8 were male, ASA score median value was 3. Opioids were administered only in 4 patients, in 6 patients the value of Ramsay scale was 5. The average duration of surgery was 59.5 minutes. No procedure was converted to general anesthesia.

CONCLUSIONS

Our preliminary experience with ventriculoatrial shunt under locoregional anesthesia demonstrates that this technique is feasible, is not associated with an increase in operating times or complications, can avoid general anesthesia, and helps to limit opioid administration in the elderly. It can therefore represent a valid option in order to improve treatment quality in these complex patients.

Scalp block for postoperative pain after craniotomy: A meta-analysis of randomized control trials

Background

Postoperative pain after craniotomy is an important clinical concern because it might lead to brain hyperemia and elevated intracranial pressure. Considering the side effects of opioid, several studies have been conducted to investigate the effect of local anesthetics, especially the scalp block, on postoperative pain. However, the strength of evidence supporting this practice for postoperative pain after craniotomy was unclear and the best occasion of scalp block was also not identified. Therefore, we conducted a meta-analysis to evaluate the efficacy, safety, and the best occasion of scalp block for postoperative pain after craniotomy.

Methods

PubMed, Embase, and the Cochrane Library databases from database inception to October 10, 2021 were searched for all randomized controlled trials evaluating the effect of scalp block on postoperative pain after craniotomy. Data were assessed by StataMP 16 software.

Results

A total of 12 studies were included. A random-effect model was used to analyze all data. Patients under scalp block earned fewer scores than the non-scalp block group in visual analogue scale at the very early period (MD = −1.97, 95% CI = −3.07 to −0.88), early period (MD = −1.84, 95% CI = −2.95 to −0.73) and intermediate period (MD = −1.16, 95% CI = −1.84 to −0.49). Scalp block could also significantly prolong the time of the first request of rescue analgesia and reduce the use of additional analgesics without a significant difference in the incidence of complications. Subgroup analysis showed there was no significant difference in analgesia effect between pre-incision scalp block and post-incision scalp block in all periods.

Conclusion

Scalp block could lead to lower pain intensity scores, more time of the first request of rescue analgesia, and fewer analgesic drugs applied in the first 12 h after craniotomy. There was no significant difference between pre-incision and post-incision scalp block in the occurrence and severity of postoperative pain.

Ultrasound-guided superficial cervical plexus block reduces opioid consumption in patients undergoing craniotomy via suboccipital retrosigmoid approach: a randomized controlled trial

INTRODUCTION

The effectiveness of superficial cervical plexus block (SCPB) at decreasing opioid use and improving hemodynamic stability during suboccipital retrosigmoid craniotomy has not been established. The aim of this study is to evaluate the analgesic effect of preoperative ultrasound-guided SCPB for craniotomy via a suboccipital retrosigmoid approach.

METHODS

This was a prospective, single-center, randomized, double-blind, parallel-group controlled trial. One hundred and six adult patients undergoing suboccipital retrosigmoid craniotomy were randomly allocated into either the SCPB group (n=53) to receive 10 mL of 0.5% ropivacaine or the control group (n=53) to receive 0.9% normal saline injected into the superficial layer of prevertebral fascia guided by ultrasound. The primary outcome was the cumulative consumption of sufentanil with patient-controlled intravenous analgesia (PCIA) within 24 hours. Secondary outcomes included the overall perioperative consumption of opioids, the area under the curve of the pain score from 1 hour to 48 hours (AUC1-48), intraoperative hemodynamic parameters, and anesthesia depth.

RESULTS

The mean PCIA pump cumulative consumption of sufentanil in the first 24 hour postoperative period was significantly lowered by SCPB (5.0 µg vs 9.8 µg, 95% CI: -8.0 to -2.4; p=0.001). The total perioperative consumption of sufentanil (45.0 µg vs 54.5 µg, 95% CI: -14.8 to -4.1; p=0.001) was also significantly decreased by SCPB. The incidence of severe pain within 24 hours was decreased by SCPB (7.5% vs 26.4%, p=0.01). SCPB significantly decreased the AUC1-48 of the pain score. Intraoperative hemodynamic parameters and anesthesia depth were similar between groups (p>0.05).

DISCUSSION

SCPB provides effective analgesia in patients undergoing craniotomy and tumor resection via suboccipital retrosigmoid approach. SCPB demonstrates an opioid-sparing effect and allows for the maintenance hemodynamic stability at an appropriate depth of anesthesia.

TRIAL REGISTRATION NUMBER

NCT04036812.

Time to medical fitness for discharge following surgical evacuation of chronic subdural haematoma with general or regional anaesthesia: a prospective randomised trial

General or regional anaesthesia can be used for chronic subdural haematoma evacuation, but no study has compared these types of anaesthesia in terms of peri-operative outcomes. This single-centre, prospective, randomised study included adult patients (age ≥ 18 years) undergoing surgical chronic subdural haematoma evacuation. Patients were randomly allocated to general (target-controlled total intravenous anaesthesia with propofol and remifentanil) or regional anaesthesia (bilateral scalp block with remifentanil sedation if required). The primary outcome measure was duration of hospital stay, based on the day patients were judged by an investigator blinded from the allocation group to be medically fit for discharge. Secondary outcomes included: rate of regional anaesthesia failure; rate of intra-operative and postoperative adverse events at 24 hours; and pain scores at 24 hours. Data from 60 patients were analysed (30 general anaesthesia and 30 regional anaesthesia). Median (IQR [range]) time until patients were judged medically fit for discharge was 3 (3-3 [2-10]) days and 3 (2-5 [2-15]) days for general and regional anaesthesia, respectively (p = 0.700). Regional anaesthesia failed in two patients. There were more intra-operative adverse events in patients who received general anaesthesia (25 vs. 11, respectively; p = 0.001). The occurrence of postoperative adverse events was similar for general and regional anaesthesia (16 vs. 13 patients, respectively; p = 0.605). In patients requiring chronic subdural haematoma evacuation, general and regional anaesthesia are comparable in terms of duration of time until medically fit for discharge and occurrence of postoperative complications. The rate of intra-operative adverse events (mainly arterial hypotension) is greater with general anaesthesia.

An Update of Neuroanesthesia for Intraoperative Brain Mapping Craniotomy

The perioperative multidisciplinary team approach has probably been best exemplified by the care of awake craniotomy patients. Advancement in anesthesia and meticulous perioperative care has supported the safety and complexity of the surgical and mapping efforts in glioma resection. The discussions in this review will emphasize on anesthetic and perioperative management strategies to prevent complications and minimize their effects if they occur, including current practice guidelines in anesthesia, updates on the applications of anesthetic medications, and emerging devices. Planning the anesthetic and perioperative management is based on understanding the pharmacology of the medications, the goals of different stages of the surgery and mapping, and anticipating potential problems.

Awake Craniotomy for Resection of Intracranial Meningioma: First Case Series From a Low- and Middle-Income Country

Introduction

Awake craniotomy (AC) has emerged as a better modality for resection of intra-axial brain tumors. The advantages are not just related to the preservation of neurological function, but also include early recovery, short hospital stay and possibly lower costs. However, data on AC for meningioma resection is deficient, likely because of concerns related to intra-operative pain and blood loss.

Methods

All patients who underwent AC, using awake through-out technique for resection of meningioma, during the last five years, were included in the study. Non-probability consecutive sampling technique was employed. Variables for demographics, and details of diagnosis and surgical procedure were recorded. The outcomes measured were length of hospital stay, worsening of neurological function during surgery and significant intra-operative or post-operative pain.

Results

Seventeen patients underwent AC for resection of meningioma during the study period. Eleven of these were grade I meningioma, and six were grade II meningioma. The mean age was 45.8 ± 10.5 years. Presenting complaints were variable, with seizures being the most common (n = 7; 41.2%). The mean duration of surgery was 180.8 ± 36.2 minutes and median estimated blood loss was 450 ml (IQR: 225 ml - 737.5 ml). The mean length of stay in the hospital was 3.1 ± 1.3 days. Only one patient had a prolonged hospital stay of seven days, because of post-operative seizures. Eleven patients (58.3%) had convexity meningioma, 4 (33.3%) had parasagittal meningioma and 1 each had a parafalcine and anterior skull-base meningioma. Simpson grade I resection was performed in 6 (41.7%) patients, grade II resection in 10 (50%) patients, and grade III resection in 1 (5.9%) patient. None of our patients had deterioration in their neurological deficits after surgery and no one required emergency intubation, conversion of surgery to general anesthesia, or redo exploration.

Conclusion

AC may be considered a safe modality for surgical resection of convexity and parasagittal meningioma, with no significant risk of intra-operative or post-operative pain, although it requires more evidence. It can be offered to patients who are at higher risk, or are not willing to undergo general anesthesia. Ultimately, it might also be beneficial in terms of reducing overall costs.

Awake craniotomy in brain tumors - Technique systematization and the state of the art

The anesthesia for awake craniotomy (AC) is a consecrated anesthetic technique that has been perfected over the years. Initially used to map epileptic foci, it later became the standard technique for the removal of glial neoplasms in eloquent brain areas. We present an AC anesthesia technique consisting of three primordial times, called awake-asleep-awake, and their respective particularities, as well as delve into the anesthetic medications used. Its use in patients with low and high-grade gliomas was favorable for the resection of tumors within the functional boundaries of patients, with shorter hospital stay and lower direct costs. The present study aims to systematize the technique based on the experience of the largest philanthropic hospital in Latin America and discusses the most relevant aspects that have consolidated this technique as the most appropriate in the surgery of gliomas in eloquent areas.

Facial palsy after temporal lobectomy for epilepsy: illustrative cases

BACKGROUND

Facial palsy is a rare, unexpected complication of temporal lobectomy (TL) for intractable epilepsy. Even without direct manipulation, the facial nerve fibers may be at risk of injury during supratentorial surgery, including TL.

OBSERVATIONS

The authors presented two cases of facial palsy after unremarkable TL. In the first case, the palsy appeared in a delayed fashion and completely resolved within weeks. In the second case, facial nerve dysfunction was observed immediately after surgery, followed by progressive recovery over 2 years. The second patient had a dehiscence of the roof of the petrous bone overlying the geniculate ganglion, which put the facial nerve at risk of bipolar coagulation thermal injury.

LESSONS

Two major mechanisms could explain the loss of facial nerve function after TL: surgery-related indirect inflammation of the nerve resulting in herpesvirus reactivation and delayed dysfunction (Bell's palsy) or indirect thermal damage to the geniculate ganglion through a dehiscent petrous roof.

Anesthetic Considerations for Functional Neurosurgery

Functional neurosurgery is a rapidly growing field that uses surgical resection, ablation, or neuromodulation to treat an assortment of neurologic and psychiatric disorders, the most common of which are movement disorders and epilepsy. Anesthesiologists caring for patients undergoing neurofunctional procedures should be aware of the anesthetic implications of patients' underlying disease as well as procedure-specific concerns, such as the effects of anesthetics on intraoperative neuromonitoring and limited access to patients due to stereotactic frames or intraoperative imaging.

Evidenced-based local anaesthesia-is there a difference in practice between specialties in a major trauma centre?

Background

Local anaesthesia (LA) is used widely in several clinical scenarios in hospital practice. A number of minor trauma wounds are treated under LA at the North Bristol Trust, and on most occasions, these patients are admitted to the emergency department (ED) and treated there. On other occasions, more complex wounds may be treated by the plastic surgery team. The aim of this study is to compare the preferences of LA agents between these departments in cases of minor trauma. The authors also present a narrative review of the literature and determine best practice.

Methods

A single-centre clinical practice survey was developed and distributed to both departments which involved two case scenarios, one involving a head injury to the occiput (scenario 1) and one nailed repair (scenario 2) both requiring treatment under LA.

Results

In both scenarios ED favoured lidocaine (89%) whereas the plastic surgery team preferred to mix solutions. In scenario 1, 89% of ED participants chose lidocaine 1%, but only 38% of the plastic surgery team chose it. Forty-two percent of ED chose to use adrenaline but 100% plastic surgery team chose it. Both teams refrained from using adrenaline in digits, but 23% of the plastic surgery team chose it. Eighty-four percent of ED chose 25G needles, and the plastic surgery team’s choices varied.

Conclusions

This study has shown marked differences in the use of LA between two specialties in a major trauma centre. There is good quality evidence to support the safety of adrenaline use in digits with the addition of sodium bicarbonate to decrease the pain inflicted to the patient upon infiltration of LA. This study serves to raise awareness of the surgical dogma around adrenaline use and provide clinicians with an evidence-based guide to managing minor trauma with LA.

Level of evidence: Not ratable.

Result of awake surgery for pediatric eloquent brain area tumors: single-center experience

PURPOSE

About half of brain tumors are located in supratentorial regions and 20% of them in eloquent brain cortex areas. The use of fMRI and intraoperative neuromonitoring allows safe surgery of these areas. Carrying out awake brain surgery (ABS) operations provides additional opportunities for direct-function monitoring. In pediatric practice, this method has not been used widely yet.

METHODS

We present the retrospective analysis of the results of pre-operative examination and surgical treatment of 12 patients with glial tumors located in eloquent cortex areas. Two patients had ABS operations twice. Intraoperative neuromonitoring was used in all the cases.

RESULTS

Twelve patients in total underwent fourteen ABS operations. According to histology results, patients with low-grade tumors prevailed, 11 (91.7%) out of 12. Seven (58.3%) patients had the tumor located in the projection of speech cortex area, four (33.3%) patients in the motor cortex area, and one (8.4%) patient in the visual cortex area. The youngest male was 8 years old. Temporary neurological deficit was diagnosed in three (25%) cases. The tumor was removed completely in 66.7% (eight) cases. Three patients were operated upon twice, two of whom had ABS operations twice. The awake phase of the surgery lasted from 30 to 110 min, 61.2 min on average.

CONCLUSIONS

Our experience has shown sufficient safety of pediatric ABS operations. The achieved functional result and radicality of tumor removal prove that further application and development of this method for children with eloquent brain area tumors (EBATs) is reasonable.

Regional Anesthesia in Neuroanesthesia Practice

Regional anesthesia has been an undervalued entity in neuroanesthetic practice. However, in the past few years, owing to the development of more advanced techniques, drugs and the prolific use of ultrasound guidance, the unrecognised potential of these modalities have been highlighted. These techniques confer the advantages of reduced requirements for local anesthetics, improved hemodynamic stability in the intraoperative period, better pain score postoperatively and reduced analgesic requirements in the postoperative period. Reduced analgesic requirement translates into lesser side effects associated with analgesic use. Furthermore, the transition from the traditional blind landmark-based techniques to the ultrasound guidance has increased the reliability and the safety profile. In this review, we highlight the commonly practised blocks in the neuroanesthesiologist's armamentarium and describe their characteristics, along with their individual particularities.

Effect of bilateral scalp nerve blocks on postoperative pain and discharge times in patients undergoing supratentorial craniotomy and general anesthesia: a randomized-controlled trial

PURPOSE

Post-craniotomy pain is a common clinical issue and its optimal management remains incompletely studied. Utilization of a regional scalp block has the potential advantage of reducing perioperative pain and opioid consumption, thereby facilitating optimal postoperative neurologic assessment. The purpose of this study was to assess the efficacy of regional scalp block on post-craniotomy pain and opioid consumption.

METHODS

We performed a prospective randomized-controlled trial in adults scheduled to undergo elective supratentorial craniotomy under general anesthesia to assess the efficacy of postoperative bilateral scalp block with 0.5% bupivacaine with 1:200,000 epinephrine compared with placebo on postoperative pain and opioid consumption. The primary outcome was the visual analogue scale (VAS) for pain at 24 hr postoperatively.

RESULTS

Eighty-nine patients were enrolled (n = 44 in block group; n = 45 in control group). There was no difference in the mean (standard deviation) VAS score at 24 hr postoperatively between the treatment group and the control group [31.2 (21.4) mm vs 23.0 (19.2) mm, respectively; mean difference, 6.6; 95% confidence interval, -2.3, 15.5; P = 0.15]. There was also no significant difference in postoperative opioid consumption. Distribution of individual VAS score and opioid consumption revealed that postoperative pain was highly variable following craniotomy. Time to hospital discharge was not different between treatment and placebo groups. No adverse events associated with scalp block were identified.

CONCLUSION

These data show that bilateral scalp blocks using bupivacaine with epinephrine did not reduce mean postoperative VAS score or overall opioid consumption at 24 hr nor the time-to-discharge from the postanesthesia care unit or from hospital.

TRIAL REGISTRATION

www.ClinicalTrials.gov, NCT00972790; registered 9 September, 2009.

Intravenous Fentanyl 4 μg per kg Administered before Scalp Pin Application is Inferior to Scalp Block in Preventing Hemodynamic Changes

Background:

Application of scalp pins for craniotomy surgeries is a noxious stimulus, causing tachycardia and hypertension, resulting in increased cerebral blood flow and elevated intracranial pressure, hence measures to attenuate this will have beneficial role.

Aims:

The aim is to compare the effectiveness of scalp block (SB) to 4 μg.kg^-1 intravenous (i.v) fentanyl in attenuating hemodynamic response to scalp pin application in patients who underwent elective craniotomy under general anesthesia.

Settings and Design:

The study design involves prospective, randomized study conducted at Tertiary care center/hospital.

Subjects and Methods:

Forty-four American Society of Anesthesiologists physical status Classes l and II patients were randomly allocated into the following groups: Group-SB (n = 22) received SB using 0.25% injection bupivacaine and Group-F (n = 22) received 1 μg.kg^-1 i.v fentanyl. Patient's heart rate (HR) and mean arterial pressure (MAP) were recorded from the application of pins till 60 min and rescue analgesic/anesthetic agents and their dosage were noted. Statistical analysis was performed comparing HR and MAP changes to application of scalp pins.

Statistical Analysis:

Software developed by the Centre for Disease Control, Atlanta, namely Epidemiological Information Package 2010 was used to derive statistical variables.

Results:

Patients were comparable in age, gender, hypertension as comorbidity, baseline HR, and MAP. Significant rise in HR was noted in Group-F till 20^th min compared to Group-SB. MAP was high from application of pins till 60^th min in Group-F compared to Group-SB. Requirement of rescue analgesics/anesthetics was high in Group-F compared to Group-SB.

Conclusion:

SB effectively attenuates hemodynamic response to application of scalp pins in patients undergoing elective craniotomy and reduces requirement of rescue analgesic and/or anesthetics.

Ultrasound-guided superficial cervical plexus block for analgesia in patients undergoing craniotomy via suboccipital retrosigmoid approach: study protocol of a randomised controlled trial

INTRODUCTION

Scalp nerve block has been proven to be an alternative choice to opioids in multimodal analgesia. However, for the infratentorial space-occupying craniotomy, especially the suboccipital retrosigmoid craniotomy, scalp nerve block is insufficient.

METHODS AND ANALYSIS

The study is a prospective, single-centre, randomised, paralleled-group controlled trial. Patients scheduled to receive elective suboccipital retrosigmoid craniotomy will be randomly assigned to the superficial cervical plexus block group or the control group. After anaesthesia induction, superficial cervical plexus nerve block will be performed under the guidance of ultrasound. The primary outcome is the cumulative consumption of sufentanil by the patient-controlled intravenous analgesia pump within 24 hours after surgery. Secondary outcomes include the cumulative consumption of sufentanil at other four time points and numerical rating scale pain severity score.

ETHICS AND DISSEMINATION

The protocol (version number: 2.0, 10 April 2019) has been approved by the Ethics Review Committee of China Registered Clinical Trials (Ethics Review No. ChiECRCT-20190047). The findings of this study will be disseminated in peer-reviewed journals and at scientific conferences.

TRIAL REGISTRATION NUMBER

NCT04036812.

Scalp Block Is Associated With Improved Recurrence Profiles in Patients Undergoing Primary Glioma Resection Surgery

BACKGROUND

Glioma is associated with high recurrence and poor survival, despite the success of tumor resection surgery. This may be partly because the immune microenvironment within a glioma is susceptible to perioperative immunosuppression. Therefore, intraoperative anesthesia-related immunomodulators, such as scalp block, intravenous anesthesia, the opioid dosage administered, and transfusions, may influence oncological outcomes among patients with glioma. The aim of this retrospective study was to investigate the influence of anesthetic techniques on oncological outcomes after craniotomy for glioma resection, particularly the effects of scalp block, intravenous anesthesia, and inhalation anesthesia.

METHODS

Consecutive patients who underwent primary glioma resection surgeries between January 2010 and December 2017 were analyzed to compare postcraniotomy oncological outcomes (progression-free survival [PFS] and overall survival) by using the Kaplan-Meier method and multivariate Cox regression analysis. A propensity score-matched regression analysis including prognostic covariates was also conducted to analyze the selected relevant anesthetic factors of the unmatched regression model.

RESULTS

A total of 230 patients were included in the final analysis. No analyzed anesthetic factor was associated with overall survival. Patients who received scalp block had a more favorable median (95% confidence interval [CI]) PFS (55.37 [95% CI, 12.63-62.23] vs. 14.07 [95% CI, 11.27-17.67] mo; P=0.0053). Scalp block was associated with improved PFS before (hazard ratio, 0.465; 95% CI, 0.272-0.794; P=0.0050) and after (hazard ratio, 0.367; 95% CI, 0.173-0.779; P=0.0091) propensity score-matched Cox regression analysis. By contrast, intravenous anesthesia, amount of opioid consumed, and transfusion were not associated with PFS.

CONCLUSIONS

The study results suggest that the scalp block improves the recurrence profiles of patients receiving primary glioma resection.

Effect of local anesthesia with lidocaine on perioperative proinflammatory cytokine levels in plasma and cerebrospinal fluid in cerebral aneurysm patients: Study protocol for a randomized clinical trial

BACKGROUND

Cerebral aneurysm surgery has significant mortality and morbidity rate. Inflammation plays a key role in the pathogenesis of intracranial aneurysms, their rupture, subarachnoid hemorrhage and neurologic complications. Proinflammatory cytokine level in blood and cerebrospinal fluid (CSF) is an indicator of inflammatory response. Cytokines contribute to secondary brain injury and can worsen the outcome of the treatment. Lidocaine is local anesthetic that can be applied in neurosurgery as regional anesthesia of the scalp and as topical anesthesia of the throat before direct laryngoscopy and endotracheal intubation. Besides analgesic, lidocaine has systemic anti-inflammatory and neuroprotective effect.Primary aim of this trial is to determine the influence of local anesthesia with lidocaine on the perioperative levels of pro-inflammatory cytokines interleukin-1β, interleukin-6, and tumor necrosis factor-α in plasma and CSF in cerebral aneurysm patients.

METHODS

We will conduct prospective randomized clinical trial among patients undergoing craniotomy and cerebral aneurysm clipping surgery in general anesthesia. Patients included in the trial will be randomly assigned to the lidocaine group (Group L) or to the control group (Group C). Patients in Group L, following general anesthesia induction, will receive topical anesthesia of the throat before endotracheal intubation and also regional anesthesia of the scalp before Mayfield frame placement, both done with lidocaine. Patients in Group C will have general anesthesia only without any lidocaine administration. The primary outcomes are concentrations of cytokines interleukin-1β, interleukin-6 and tumor necrosis factor-α in plasma and CSF, measured at specific timepoints perioperatively. Secondary outcome is incidence of major neurological and infectious complications, as well as treatment outcome in both groups.

DISCUSSION

Results of the trial could provide insight into influence of lidocaine on local and systemic inflammatory response in cerebrovascular surgery, and might improve future anesthesia practice and treatment outcome. TRIAL IS REGISTERED AT CLINICALTRIALS.GOV:: NCT03823482.

REGIONAL ANESTHESIA FOR NEUROSURGERY

During neurosurgery procedures it is vital to assure optimal cerebral perfusion and oxygenation. Despite physiological autoregulation of brain perfusion, maintaining hemodynamic stability and good oxygenation during anesthesia is vital for success. General anesthesia with mechanical ventilation and current drugs provide excellent hemodynamic condition and it is the first choice for most neurosurgery procedures. However, sometimes it is very hard to avoid brief increase or decrease in blood pressure especially during period of intense pain, or without pain stimulation. This could be detrimental for patients presented with high intracranial pressure and brain edema. Modifying anesthesia depth or treatment with vasoactive drugs usually is needed to overcome such circumstances. On the other hand it is important to wake the patients quickly after anesthesia for neurological exam. That is why regional anesthesia of scalp and spine could show beneficial effects by decreasing pain stimuli and hemodynamic variability with sparing effect of anesthetics drugs. Also regional techniques provide excellent postoperative pain relief, especially after spinal surgery

Conscious sedation with dexmedetomidine compared with asleep-awake-asleep craniotomies in glioma surgery: an analysis of 180 patients

OBJECTIVE

Awake craniotomies have become a feasible tool over time to treat brain tumors located in eloquent regions. Different techniques have been applied in neurooncology centers. Both “asleep-awake-asleep” (asleep) and “conscious sedation” were used subsequently at the authors’ neurosurgical department. Since 2013, the authors have only performed conscious sedation surgeries, predominantly using the α2-receptor agonist dexmedetomidine as the anesthetic drug. The aim of this study was to compare both mentioned techniques and evaluate the clinical use of dexmedetomidine in the setting of awake craniotomies for glioma surgery.

METHODS

The authors retrospectively analyzed patients who underwent operations either under the asleep condition using propofol-remifentanil or under conscious sedation conditions using dexmedetomidine infusions. In the asleep group patients were intubated with a laryngeal mask and extubated for the assessment period. Adverse events, as well as applied drugs with doses and frequency of usage, were recorded.

RESULTS

From 224 awake surgeries between 2009 and 2015, 180 were performed for the resection of gliomas and included in the study. In the conscious sedation group (n = 75) significantly fewer opiates (p < 0.001) and vasoactive (p < 0.001) and antihypertensive (p < 0.001) drugs were used in comparison with the asleep group (n = 105). Furthermore, the postoperative length of stay (p < 0.001) and the surgical duration (p < 0.001) were significantly lower in the conscious sedation group.

CONCLUSIONS

Use of dexmedetomidine creates excellent conditions for awake surgeries. It sedates moderately and acts as an anxiolytic. Thus, after ceasing infusion it enables quick and reliable clinical neurological assessment of patients. This might lead to reducing the amount of administered antihypertensive and vasoactive drugs as well as the length of hospitalization, while likely ensuring more rapid surgery.