Intracranial Neurosurgical Procedures Research Articles

Multimodal Use of Contact Endoscopy in Neurosurgery: Case Series with Technical Note and Literature Review

BackgroundOriginally adopted for the cytological screening of cervical and uterine cancer, contact endoscopy (CE) is now widely used in several fields of oncological surgery. The CE method, with magnification power up to 150x, was designed to enhance visualization and identify microscopic changes indicative of pre-cancerous and cancerous lesions at early stages. In this pilot study, we evaluated the multimodal applications of CE during different endoscopic intracranial neurosurgical procedures. MethodsTwenty patients with skull base lesions underwent surgery using different minimally invasive endoscopic approaches (endonasal, transorbital, and supraorbital). CE was used to distinguish the pathology from the surrounding healthy tissue by positioning the endoscope either in proximity or directly onto the target tissue. Special attention was given to the visualization of the margins of the lesion to differentiate compression/displacement from infiltration of the normal surrounding tissue. ResultsWith its unprecedented range of magnification, CE could clearly identify the microvascular pattern and cytological architecture of a tissue not detectable by simple white light endoscopy, with no reported damage due to heat transmission or iatrogenic injuries. All the lesions diagnosed as “presumed neoplastic tissue” by CE were confirmed by histopathology. The most promising results were observed in surgeries for meningioma and pituitary adenoma, as these lesions exhibit distinctive microvascular networks. ConclusionCE represents a new and effective technique for the in vivo identification of pathological microvascular and tissue features, allowing preservation of normal tissue during different endoscopic approaches. The use of CE could improve diagnostic accuracy and assist in intraoperative decision-making, becoming a key tool in various applications in neurosurgical field.

Nonsteroidal Anti-inflammatory Medications in Cranial Neurosurgery: Balancing Opioid-Sparing Analgesia with Bleeding Risk

Post-craniotomy pain is a common problem frequently encountered by neurosurgeons. This is typically managed with opioids; however, opioids have been shown to increase intracranial pressure by way of hypercapnia and straining from the associated constipation. Additionally, opioids can confound and mask the neurologic examination of post-craniotomy patients as well as be the nidus for a potential opioid addiction. Thus, alternative solutions for opioids have been a major topic of investigation within the neurosurgical community. Non-steroidal anti-inflammatory drugs (NSAIDs), present as a potential solution due to their non-addictive and analgesic properties, but utilization of NSAIDs in neurosurgical patients has been controversial given that NSAIDs alter platelet function. Whether the degree to which NSAIDs alter platelet function and bleeding time to clinically relevant manner has remained controversial; although, there have been several well-designed studies concluding that the utilization of NSAIDs in post-craniotomy patients does not increase the risk of postoperative bleeding. Herein, we review the pharmacology, efficacy, and safety of NSAIDs with a particular emphasis on NSAID use for post intracranial neurosurgical procedure pain management.

Letter to the Editor Regarding “Perioperative Risk Factors Associated with Unplanned Neurological Intensive Care Unit Events Following Elective Infratentorial Brain Tumor Resection”

Awake craniotomy (AC) is the preferred option for the resection of tumors adjacent to eloquent cortical areas and in cases of intractable epilepsy. It is mostly used to maintain the integrity of the brain during intracranial neurosurgical procedures. Awake craniotomy requires the use of ideal anesthetics, hypnotics, and analgesics to balance sedation, prompt the reversal of sedation, and prevent respiratory depression while maintaining communication between patient and medical team. Although a wide variety of anesthetics and hypnotics have been used for awake craniotomy over the past several decades, the optimal drug for the procedure has yet to be determined. The purpose of this meta-analysis was to compare dexmedetomidine and propofol in terms of intraoperative adverse events (i.e., hypertension, hypotension, nausea, vomiting, respiratory depression), patient and surgeon satisfaction, and procedure duration.We searched PubMed, Google Scholar, and the Cochrane Library for relevant articles published between the inception of these databases and April of 2022. The systematic search yielded 781 articles. After screening, we excluded 778 articles. The remaining three articles reporting 138 patients were selected for meta-analysis.This meta-analysis showed no statistically significant difference between propofol and dexmedetomidine related to intraoperative adverse events, patient satisfaction, or procedure duration. The only statistically significant result was surgeon satisfaction, which appeared to be higher in the dexmedetomidine group.Further high-quality randomized and controlled trials are needed to find a preferred agent for intraoperative sedation in awake craniotomy.

Holographic patient tracking after bed movement for augmented reality neuronavigation using a head-mounted display

BackgroundHolographic neuronavigation has several potential advantages compared to conventional neuronavigation systems. We present the first report of a holographic neuronavigation system with patient-to-image registration and patient tracking with a reference array using an augmented reality head-mounted display (AR-HMD).MethodsThree patients undergoing an intracranial neurosurgical procedure were included in this pilot study. The relevant anatomy was first segmented in 3D and then uploaded as holographic scene in our custom neuronavigation software. Registration was performed using point-based matching using anatomical landmarks. We measured the fiducial registration error (FRE) as the outcome measure for registration accuracy. A custom-made reference array with QR codes was integrated in the neurosurgical setup and used for patient tracking after bed movement.ResultsSix registrations were performed with a mean FRE of 8.5 mm. Patient tracking was achieved with no visual difference between the registration before and after movement.ConclusionsThis first report shows a proof of principle of intraoperative patient tracking using a standalone holographic neuronavigation system. The navigation accuracy should be further optimized to be clinically applicable. However, it is likely that this technology will be incorporated in future neurosurgical workflows because the system improves spatial anatomical understanding for the surgeon.

Therapeutic anticoagulation for venous thromboembolism after recent brain surgery: Evaluating the risk of intracranial hemorrhage

ObjectiveVenous thromboembolism (VTE) is particularly prevalent in neurosurgical patients. A major dilemma arises when a patient needs to be treated with therapeutic anticoagulation during the early days after brain surgery due to the concern of intracranial hemorrhage (ICH). There is still a lack of studies regarding the optimal time to start therapeutic anticoagulation and risk assessment of ICH in this setting. This study aims to assess the risk of ICH for patients with venous thromboembolism treated with therapeutic anticoagulation started within the first 30 days after intracranial neurosurgical procedure. Patients and methodsThis study was an analytical observational research based on a retrospective record review of VTE patients submitted to therapeutic anticoagulation started within the first 30 days after intracranial neurosurgical procedure at Paulo Niemeyer State Brain Institute, from September 2013 to February 2020. Patients’ clinical and surgical data, anticoagulation drug therapy, time interval between surgery and start of therapeutic anticoagulation, bleeding complications and hemorrhage-related deaths were some of variables evaluated. A p value < 0.05 was considered statistically significant. ResultsA series of 53 consecutive patients and 54 intracranial neurosurgical procedures met the criteria. Twenty-nine (53.7 %) patients were treated with warfarin, 21 (38.9 %) with new oral anticoagulant (NOAC) and 4 (7.4 %) only with enoxaparin. VTE diagnosis between the postoperative days 0 and 4 was statistically associated with a delay in starting therapeutic anticoagulation of more than two days (p < 0.001). The frequency of bleeding complication was statistically significant higher in patients treated with warfarin (p = 0.03). Although with no statistical significance, there were a higher rate of ICH in patients receiving warfarin (13.8 % vs. 0% in NOAC group, p = 0.13). There was no statistical difference about ICH incidence between the postoperative intervals from 2nd to 7th, 8th to 14th, 15th to 21 st and 22th to 29th days (p = 0.35). Hemorrhage-related mortality rate was 3.7 %. ConclusionICH was not statistically associated with the timing of therapeutic anticoagulation after brain surgery between the 2nd and 29th postoperative days, which may encourage the strategy of early treatment considering the life-threatening potential of VTE. However, the risk of ICH should not be ignored in the setting of warfarin use, which had a remarkable incidence of 13.8 %. Warfarin must be used cautiously, especially in high-grade gliomas.

Risk Factors and Mechanisms of Postoperative Delirium After Intracranial Neurosurgical Procedures

Postoperative delirium (POD) is a condition characterized by cerebral dysfunction or failure and associated with high morbidity and mortality, prolonged intensive care unit and hospital stay, increased costs and long-term disability. The risk factors can be divided into three categories: preoperative, intraoperative, and postoperative. POD is underrecognized, underdiagnosed, and undertreated condition which can also lead to potentially life-threatening conditions. Prevention and treatment of POD include adequate perioperative pain control, maintenance of optimal blood pressure, water-electrolyte balance, hypo- and hyperglycemia, sleep hygiene. Despite POD has been extensively studied in various types of surgery, there is not enough evidence on POD in intracranial neurosurgery. Patients undergoing open craniotomy might be at particular risk because on top of the above-mentioned factors, they also might have a direct neurosurgical brain injury. Future research on the POD in neurosurgical patients after intracranial interventions is needed. A bibliographic search was performed in the MEDLINE and PubMed virtual library. The following descriptors were used: POD, neurosurgery, anesthesia, and POD, postoperative pain management and POD, water and electrolyte imbalance and POD, neurochemistry of POD. We included in this review original and review articles in the English language. Majority of non-neurosurgical patients have multiple risk factors for POD (preoperative, intraoperative, and postoperative); patients undergoing intracranial neurosurgery on top of that might have additional risks associated with neurosurgical pathology (brain tumor, cerebral hemorrhage, and severe traumatic injury) as well as neurosurgery-induced brain injury can also appear to be a contributing factor.

Risk Factors and Mechanisms of Postoperative Delirium After Intracranial Neurosurgical Procedures.

Postoperative delirium (POD) is a condition characterized by cerebral dysfunction or failure and associated with high morbidity and mortality, prolonged intensive care unit and hospital stay, increased costs and long-term disability. The risk factors can be divided into three categories: preoperative, intraoperative, and postoperative. POD is underrecognized, underdiagnosed, and undertreated condition which can lead to potentially life-threatening conditions. Prevention and treatment of POD include adequate perioperative pain control, maintenance of optimal blood pressure, water-electrolyte balance, hypoglycemia, hyperglycemia, sleep hygiene. Despite POD has been extensively studied in various types of surgery, there is not enough evidence on POD in intracranial neurosurgery. Patients undergoing open craniotomy might be at particular risk because on top of the above-mentioned factors, they also can have a direct neurosurgical brain injury. Future research on the POD in neurosurgical patients after intracranial interventions is needed. A bibliographic search was performed in the MEDLINE and PubMed virtual library. The following descriptors were used: POD, neurosurgery, anesthesia and POD, postoperative pain management and POD, water and electrolyte imbalance and POD, neurochemistry of POD. We included in this review original and review articles in the English language. Majority of non-neurosurgical patients have multiple risk factors for POD (preoperative, intraoperative, and postoperative); patients undergoing intracranial neurosurgery might have additional risks associated with neurosurgical pathology (brain tumor, cerebral hemorrhage, and severe traumatic brain injury) as well as neurosurgery-induced brain injury can also appear to be a contributing factor.

Development of a novel frameless skull-mounted ball-joint guide array for use in image-guided neurosurgery.

Successful convection-enhanced delivery of therapeutic agents to subcortical brain structures requires accurate cannula placement. Stereotactic guiding devices have been developed to accurately target brain nuclei. However, technologies remain limited by a lack of MRI compatibility, or by devices' size, making them suboptimal for direct gene delivery to brain parenchyma. The goal of this study was to validate the accuracy of a novel frameless skull-mounted ball-joint guide array (BJGA) in targeting the nonhuman primate (NHP) brain. Fifteen MRI-guided cannula insertions were performed on 9 NHPs, each targeting the putamen. Optimal trajectories were planned on a standard MRI console using 3D multiplanar baseline images. After cannula insertion, the intended trajectory was compared to the final trajectory to assess deviation (euclidean error) of the cannula tip. The average cannula tip deviation was 1.18 ± 0.60 mm (mean ± SD) as measured by 2 independent reviewers. Topological analysis showed a superior, posterior, and rightward directional bias, and the intra- and interclass correlation coefficients were > 0.85, indicating valid and reliable intra- and interobserver evaluation. The data demonstrate that the BJGA can be used to reliably target subcortical brain structures by using MRI guidance, with accuracy comparable to current frameless stereotactic systems. The size and versatility of the BJGA, combined with a streamlined workflow, allows for its potential applicability to a variety of intracranial neurosurgical procedures, and for greater flexibility in executing MRI-guided experiments within the NHP brain.

General anesthesia considerations in CADASIL disease

CADASIL (cerebral arteriopathy, autosomal dominant, with subcortical infarcts and leukoencephalopathy) disease is an inherited systemic arterial disease that affects the small and medium calibre cerebral vessels. Around 500 families are affected in the world, most of them in Europe. It is characterised by migraine attacks, subcortical dementia, neuropsychiatric disorders, and recurrent ischaemic strokes. The objective of this article is to describe, for the first time in the literature, the management by general anaesthesia of an intracranial neurosurgical procedure in a patient with CADASIL disease. Continuous monitoring of blood pressure is considered essential, as well as the maintenance of normocapnia and normothermia to avoid the development of new cerebrovascular accidents. This disease is relevant due to its anaesthetic implications and the few publications to date.

Prospective Multicenter Surveillance Study of Surgical Site Infection after Intracranial Procedures in Korea : A Preliminary Study.

ObjectiveThis study aimed to investigate the rates, types, and risk factors of surgical site infection (SSI) following intracranial neurosurgical procedures evaluated by a Korean SSI surveillance system. MethodsThis was a prospective observational study of patients who underwent neurosurgical procedures at 29 hospitals in South Korea from January 2017 to June 2017. The procedures included craniectomy, craniotomy, cranioplasty, burr hole, and ventriculoperitoneal shunt. Univariate and multivariate logistic regression analyses were performed. ResultsOf the 1576 cases included, 30 showed infection, for an overall SSI rate of 1.9%. Organ/space infection was the most common, found in 21 out of the 30 cases (70%). Staphylococcus aureus was the most common (41%) of all bacteria, and Serratia marcescens (12%) was the most common among gram-negative bacteria. In univariate analyses, the p-values for age, preoperative hospital stay duration, and over T-hour were <0.2. In a multivariate analysis of these variables, only preoperative hospital stay was significantly associated with the incidence of SSI (p<0.001), whereas age and over T-hour showed a tendency to increase the risk of SSI (p=0.09 and 0.06). ConclusionSurveillance systems play important roles in the accurate analysis of SSI. The incidence of SSI after neurosurgical procedures assessed by a national surveillance system was 1.9%. Future studies will provide clinically useful results for SSI when data are accumulated.

Accuracy Validation of Neuronavigation Comparing Headholder-Based System with Head-Mounted Array—A Cadaveric Study

Neuronavigation is widely used for intracranial neurosurgical procedures and is commonly based on the standard reference array being fixed to the headholder. Some cases require the reference array to be attached directly to the head. The aim of this cadaveric study was to compare operational accuracy of a head-mounted reference array with the standard headholder-based system. Navigation accuracy was evaluated with 10 cadaveric specimens. Each specimen was prepared with 8 titanium microscrews that served as reference points on the external skull, and computed tomography was performed. Registration of all specimens was done using surface matching with infrared laser on three-dimensional reconstructed high-resolution computed tomography. In all 10 specimens, the head-mounted reference array and headholder-based system were compared by 10 repetitive measurements. The deviation was evaluated for each screw and compared using nonparametric Mann-Whitney U test between groups and screws. A Bland-Altman plot was generated for comparison. A total of 1600 measurements were conducted. Mean deviation was 1.97 mm (95% confidence interval, 1.90-2.03 mm) with the head-mounted reference array and 2.10 mm (95% confidence interval, 2.04-2.18 mm) with the headholder based system. There was no significant difference between methods in 9 of 10 specimens. In 1 specimen, the head-mounted array was superior. The deviation in either method showed a significant correlation, indicating high pertinence for registration (P < 0.001). Navigation with the head-mounted reference array demonstrated comparable accuracy to the headholder-based system and can be used without reduced accuracy. Careful registration is mandatory.

The Utility of Routine Intensive Care Admission for Patients Undergoing Intracranial Neurosurgical Procedures: A Systematic Review.

Patients who have undergone intracranial neurosurgical procedures have traditionally been admitted to an intensive care unit (ICU) for close postoperative neurological observation. The purpose of this study was to systematically review the evidence for routine ICU admission in patients undergoing intracranial neurosurgical procedures and to evaluate the safety of alternative postoperative pathways. We were interested in identifying studies that examined selected patients who presented for elective, non-emergent intracranial surgery whose postoperative outcomes were compared as a function of ICU versus non-ICU admission. A systematic review was performed in July 2016 using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist of the Medline database. The search strategy was created based on the following key words: "craniotomy," "neurosurgical procedure," and "intensive care unit." The nine articles that satisfied the inclusion criteria yielded a total of 2227 patients. Of these patients, 879 were observed in a non-ICU setting. The most frequent diagnoses were supratentorial brain tumors, followed by patients with cerebrovascular diseases and infratentorial brain tumors. Three percent (30/879) of the patients originally assigned to floor or intermediate care status were transferred to the ICU. The most frequently observed neurological complications leading to ICU transfer were delayed postoperative neurological recovery, seizures, worsening of neurological deficits, hemiparesis, and cranial nerves deficits. Our systematic review demonstrates that routine postoperative ICU admission may not benefit carefully selected patients who have undergone elective intracranial neurosurgical procedures. In addition, limiting routine ICU admission may result in significant cost savings.

Dexmedetomidine versus labetalol infusions for controlling emergence hypertension in cranial surgeries for supratentorial tumors

BackgroundAcute hypertension is a common accompaniment during emergence from anesthesia especially in intracranial neurosurgical procedures and may be associated with the development of intracranial hematoma. Although various drugs have been evaluated, management of emergence hypertension in this subset of patients continues to be a challenge for anesthesiologists.MethodologySeventy-five patients ASA (I-II) scheduled for supratentorial craniotomy under general anesthesia were randomly allocated to one of three groups at the time of dural closure: Group “dex” received dexmedetomidine infusion in a rate of 1 μg/kg/hr, Group “labetalol” received labetalol infusion in a rate of 0.5 mg/kg/hr, and Group “control” a control group where patients received saline infusion at the same rate of dexmedetomidine and labetalol. Hypertensive episodes were managed with nitroglycerin at a dose starting from 1 μg/kg/min if systolic blood pressure exceeded 25% of its preinduction value. Hemodynamic parameters as well as the number of patients, the total dose of nitroglycerin required in each group and the time to extubation were recorded.ResultsDexmedetomidine and labetalol had a significant effect in reducing SBP, MAP, DBP, HR during emergence from anesthesia, with more reduction of the SBP, MAP and DBP in the dexmedetomidine group and of the HR in the labetalol group in comparison with the other two groups. The number of patients needing nitroglycerin was 8 representing 32% of patients in dexmedetomidine group, 5 representing 20% of patients in labetalol group and 22 representing 88% of patients in control group (P value = 0.032). Time to emergence from anesthesia was comparable in the three groups.ConclusionBoth dexmedetomidine and labetalol had favorable effects on hemodynamics at time of emergence from anesthesia in comparison with control group without prolongation of the time of extubation.

Body temperature affects cerebral hemodynamics in acutely brain injured patients: an observational transcranial color-coded duplex sonography study.

IntroductionTemperature changes are common in patients in a neurosurgical intensive care unit (NICU): fever is frequent among severe cases and hypothermia is used after cardiac arrest and is currently being tested in clinical trials to lower intracranial pressure (ICP). This study investigated cerebral hemodynamics when body temperature varies in acute brain injured patients.MethodsWe enrolled 26 patients, 14 with acute brain injury who developed fever and were given antipyretic therapy (defervescence group) and 12 who underwent an intracranial neurosurgical procedure and developed hypothermia in the operating room; once admitted to the NICU, still under anesthesia, they were re-warmed before waking (re-warming group). We measured cerebral blood flow velocity (CBF-V) and pulsatility index (PI) at the middle cerebral artery using transcranial color-coded duplex sonography (TCCDS).ResultsIn the defervescence group mean CBF-V decreased from 75 ± 26 (95% CI 65 to 85) to 70 ± 22 cm/s (95% CI 61 to 79) (P = 0.04); the PI also fell, from 1.36 ± 0.33 (95% CI 1.23 to 1.50) to 1.16 ± 0.26 (95% CI 1.05 to 1.26) (P = 0.0005). In the subset of patients with ICP monitoring, ICP dropped from 16 ± 8 to 12 ± 6 mmHg (P = 0.003). In the re-warming group mean CBF-V increased from 36 ± 10 (95% CI 31 to 41) to 39 ± 13 (95% CI 33 to 45) cm/s (P = 0.04); the PI rose from 0.98 ± 0.14 (95% CI 0.91 to 1.04) to 1.09 ± 0.22 (95% CI 0.98 to 1.19) (P = 0.02).ConclusionsBody temperature affects cerebral hemodynamics as evaluated by TCCDS; when temperature rises, CBF-V increases in parallel, and viceversa when temperature decreases. When cerebral compliance is reduced and compensation mechanisms are exhausted, even modest temperature changes can greatly affect ICP.

Anesthetic Management of Neurosurgical Procedures During Pregnancy

Neurosurgical disorders are rare during pregnancy and challenge the anesthesiologist with conflicting anesthetic considerations and little evidence to guide decision-making. Our objective was to review the anesthetic management of pregnant patients undergoing intracranial neurosurgery at our institution and to describe the perioperative complications and outcomes. We used our institutional Discharge Abstract Database to identify patients assigned both neurological and obstetrical International Classification of Disease 10-A codes between April 1, 2001 and March 1, 2012. Pregnant patients who underwent intracranial neurosurgical procedures underwent a detailed chart review to extract demographic data and details about their anesthetic management and outcome. Nine patients underwent full chart review with a median age of 28 (range, 17 to 35) years and a gestational age of 23 (range, 7 to 30) weeks. Patients underwent a craniotomy for vascular lesions (4), neoplasms (3), and traumatic brain injuries (2). One patient was hyperventilated (PaCO2 28 mmHg), and mannitol and furosemide were used in 6 and 3 patients, respectively, without complication. Maternal neurological outcomes were good in 5 patients (Glasgow Outcome Scale of >3), poor in 3 patients (Glasgow Outcome Scale 3), and 1 patient died. Fetal outcomes were good in 5 patients and poor in 4 patients (1 therapeutic abortion, 3 intrauterine fetal demises). All cases of fetal distress or demise were either remote or occurred before the anesthetic management. Pregnant patients undergoing neurosurgery experience a high rate of morbidity and mortality. There were no adverse outcomes directly attributed to the use of osmotic diuretics and hyperventilation in our series.

Surgical site infections in standard neurosurgery procedures– a study of incidence, impact and potential risk factors

Objectives. Surgical site infections (SSIs) may be devastating for the patient and they carry high economic costs. Studies of SSI after neurosurgery report an incidence of 1–11%. However, patient material, follow-up time and definition of SSI have varied. In the present study we prospectively recorded the prevalence of SSI 3 months after standard intracranial neurosurgical procedures. The incidence, impact and risk factors of SSI were analysed. Methods. We included patients admitted during 2010 to our unit for postoperative care after standard neurosurgical procedures. SSI was defined as evident with positive cultures from surgical samples or CSF, and/or purulent discharge during reoperation. Follow-up was done after 3 and 12 months and statistics was obtained after 3 months. The predictive values on the outcome of demographic and clinical factors describing the surgical procedure were evaluated using linear regression. Results. A total of 448 patients were included in the study and underwent a total of 466 procedures. Within 3 and 12 months, 33 and 88 patients, respectively, had died. Of the surviving patients, 20 (4.3% of procedures) developed infections within 3 months and another 3 (4.9% of procedures) within 12 months. Risk factors for SSI were meningioma, longer operation time, craniotomy, dural substitute, and staples in wound closure. Patients with SSI had significantly longer hospital stay. Multivariate analysis showed that factors found significant in univariate analysis frequently occur together. Discussion. We studied the prevalence of SSI after 3 and 12 months in a prospective 1-year material with standard neurosurgical procedures and found it to be 4.3% and 4.9%, respectively. The analysis of the results showed that a combination of parameters indicating a longer and more complicated procedure predicted the development of SSI. Our conclusion is that the prevention of SSI has to be done at many levels, especially with patients undergoing long surgical procedures.

P196: Post-neurosurgical meningitis

Objectives To study the etiology, management and risk factors of post-neurosurgical meningitis. Methods A prospective and retrospective observational study of six patients admitted over a period of one year, who developed meningitis following various neurosurgical procedures. Antimicrobial treatment was initiated empirically based on clinical and epidemiological background and later modified based on results of culture and susceptibility. Retrospectively, risk factors associated with each case were analyzed. Results Patients had undergone either intracranial or spinal neurosurgical procedures with placement of ventricular or spinal drains. Features of meningitis developed between 3 days to 2 months after surgery. Various organisms isolated were Staphylococcus aureus, vancomycin resistant enterococci (VRE), Escherichia coli, Pseudomonas aeruginosa, Pseudomonas stutzeri and Klebsiella pneumoniae. Antibiotics used for treatment included cloxacillin, linezolid, daptomycin, meropenem, ceftriaxone, ciprofloxacin and colistin; based on organism identification and susceptibility. 1 patient with lumbar drain related meningitis, treated with meropenem and intrathecal colistin showed dramatic response. 1 patient with external ventricular drain (EVD) related meningitis caused by Klebsiella pneumoniae and another with infected pseudomeningocele by Pseudomonas stutzeri, also improved. 3 patients did not respond well and expired. Of these, 1 had infection with VRE, and 2 had incomplete source control with retention of foreign implants. Risk factors presumed to have role in etiology and poor outcomes were uncontrolled diabetes, obesity, non-removal of ventriculoperitoneal shunt, suboptimal duration of antimicrobial treatment, disconnection of lumbar drain; prolonged duration (>5 days), blockage and multiple changes of EVD. Factors related to surgical technique like intraoperative dural tear and injury to lumbar vertebrae were also involved. Conclusion Although post-neurosurgical meningitis is a low incidence infection, the consequences are grave. Therefore, effective prevention with stringent infection control measures should be the goal.

Changes in serum electrolytes after intracranial neurosurgical procedures

University Hospital Center ‘Mother Theresa’, Department of Anaesthesiology and Intensive Care, Tirana, Albania

Comparison of Functional Outcomes in Low- and High-Grade Astrocytoma Rehabilitation Inpatients

To compare inpatient rehabilitation outcomes between patients with low- and high-grade astrocytoma. A retrospective review of medical records for patients admitted from September 1, 1996, to June 30, 2008, to the inpatient rehabilitation unit at a tertiary care cancer center. A high-grade (21 of 443 patients) and low-grade astrocytoma (21 of 24 patients) group were matched on three of five criteria in the order of importance: area of brain involvement (divided into left cerebral, right cerebral, midline and/or bilateral cerebral, and infratentorial), single vs. multiple intracranial neurosurgical procedures, age (within 10 yrs), period of rehabilitation admission (within 3 yrs), and sex. Descriptive statistics were used to compare demographic data and scores in four categories (total, activities of daily living, mobility, and cognition) from the patients' functional independence measure assessment. No significant (P > 0.05) differences were found in demographics or efficiency between the two groups. The high-grade group had significantly (P < 0.05) higher total gain and longer stay in inpatient rehabilitation (mean +/- standard deviation, 21.7 +/- 10.1 vs. 13.0 +/- 9.3 and 13 +/- 7.1 day vs. 9 +/- 6.2 days, respectively) than did the low-grade astrocytoma group. Compared with patients with low-grade astrocytoma, patients with high-grade astrocytoma had higher total functional independence measure gain but also longer lengths of stay. Functional independence measure efficiencies were comparable between the two groups. Our results parallel those of previous rehabilitation outcome studies comparing patients with brain tumors with patients with brain injuries of other etiologies. Larger matched studies are needed for this patient population.

Transfusion practice in neuroanesthesia

Perioperative transfusion thresholds in the neurosurgical patient are undefined. Many neurosurgical procedures are associated with significant risk of bleeding. This review will summarize the current understanding of blood transfusion in the neurosurgical patient, as well as other blood component therapies and blood conservation strategies. Transfusion of red blood cells has been demonstrated to improve cerebral oxygen delivery. Clinical studies on transfusion-related morbidity and mortality in the neurosurgical patient are limited. Recent findings in both subarachnoid hemorrhage and traumatic brain injured patients have shown worse outcomes in patients with anemia (Hb <9.0 g/dl) yet transfusion of red blood cells may not be associated with improved outcome. Perioperative transfusion management for intracranial neurosurgical procedures presents the clinician with multiple challenges. Clinical evidence is sparse with view to an optimal hemoglobin level, yet anemia is known to be a predictor of poor outcome in many neurosurgical patients. Transfusion thresholds from other patient populations may not apply to this group and further prospective investigations are desperately needed. Until then, clinicians should focus on an individualized assessment of anemia tolerance, consider blood conservation strategies and understand the potential risks and benefits of blood transfusion.