Polyspikes and Rhythmic Polyspikes During Volatile Induction of General Anesthesia With Sevoflurane Result in Bispectral Index Variations.

BACKGROUND: Although electroencephalography (EEG)-based indices may show artifactual values, raw EEG signal is seldom used to monitor the depth of volatile induction of general anesthesia (VIGA). The current analysis aimed to identify whether bispectral index (BIS) variations reliably reflect the actual depth of general anesthesia during presence of different types of epileptiform patterns (EPs) in EEGs during induction of general anesthesia. METHODS: Sixty patients receiving either VIGA with sevoflurane using increasing concentrations (group VIMA) or vital capacity (group VCRII) technique or intravenous single dose of propofol (group PROP) were included. Monitoring included facial electromyography (fEMG), fraction of inspired sevoflurane (FiAA), fraction of expired sevoflurane (FeAA), minimal alveolar concentration (MAC) of sevoflurane, BIS, standard EEG, and hemodynamic parameters. RESULTS: In the PROP group no EPs were observed. During different stages of VIGA with sevoflurane in the VIMA and VCRII groups, presence of polyspikes and rhythmic polyspikes in patients' EEGs resulted in artifactual BIS values indicating a false awareness/wakefulness from anesthesia, despite no concomitant change of FiAA, FeAA, and MAC of sevoflurane. Periodic epileptiform discharges did not result in aberrant BIS values. CONCLUSION: Our results suggest that raw EEG correlate it with values of BIS, FiAA, FeAA, and MAC of sevoflurane during VIGA. It seems that because artifactual BIS values indicating false awareness/wakefulness as a result of presence of polyspikes and rhythmic polyspikes in patients' EEGs may be misleading to an anesthesiologist, leading to unintentional administration of toxic concentration of sevoflurane in ventilation gas.

Biology, Physics and Genetics of Intracranial Aneurysm Formation: A Review.

Intracranial aneurysms (IAs) are persistent, localised dilatations of the arterial wall that are found in approximately 3% of the general population. The most severe complication of IAs is rupture, which results in devastating consequences such as subarachnoid haemorrhage and brain damage with serious neurological sequelae. Numerous studies have characterised the mechanisms underlying IA development and growth and identified a number of environmental modifiable (smoking, hypertension) and nonmodifiable risk factors (related to the histology of cerebral arteries and genetic factors) in its pathogenesis. Haemodynamic stress also likely plays a crucial role in the formation of IAs and is conditioned by the geometry and morphology of the vessel tree, but its role in the natural history of unruptured IAs remains poorly understood; it is believed that changes in blood flow might generate the haemodynamic forces that are responsible for damage to the vascular wall and vessel remodelling that lead to IA formation. This review summarises the most relevant data on the current theories on the formation of IAs, with particular emphasis on the roles of special conditions resulting from the microscopic anatomy of intracranial arteries, haemodynamic factors, bifurcation morphometry, inflammatory pathways, and the genetic factors involved in IA formation.

Preservation of the Hypoxic Transcriptome in Glioblastoma Patient-Derived Cell Lines Maintained at Lowered Oxygen Tension.

Despite numerous efforts aiming to characterise glioblastoma pathology (GBM) and discover new therapeutic strategies, GBM remains one of the most challenging tumours to treat. Here we propose the optimisation of in vitro culturing of GBM patient-derived cells, namely the establishment of GBM-derived cultures and their maintenance at oxygen tension mimicking oxygenation conditions occurring within the tumour. To globally analyse cell states, we performed the transcriptome analysis of GBM patient-derived cells kept as spheroids in serum-free conditions at the reduced oxygen tension (5% O2), cells cultured at atmospheric oxygen (20% O2), and parental tumour. Immune cells present in the tumour were depleted, resulting in the decreased expression of the immune system and inflammation-related genes. The expression of genes promoting cell proliferation and DNA repair was higher in GBM cell cultures when compared to the relevant tumour sample. However, lowering oxygen tension to 5% did not affect the proliferation rate and expression of cell cycle and DNA repair genes in GBM cell cultures. Culturing GBM cells at 5% oxygen was sufficient to increase the expression of specific stemness markers, particularly the PROM1 gene, without affecting neural cell differentiation markers. GBM spheroids cultured at 5% oxygen expressed higher levels of hypoxia-inducible genes, including those encoding glycolytic enzymes and pro-angiogenic factors. The genes up-regulated in cells cultured at 5% oxygen had higher expression in parental GBMs compared to that observed in 20% cell cultures, suggesting the preservation of the hypoxic component of GBM transcriptome at 5% oxygen and its loss in standard culture conditions. Evaluation of expression of those genes in The Cancer Genome Atlas dataset comprising samples of normal brain tissue, lower-grade gliomas and GBMs indicated the expression pattern of the indicated genes was specific for GBM. Moreover, GBM cells cultured at 5% oxygen were more resistant to temozolomide, the chemotherapeutic used in GBM therapy. The presented comparison of GBM cultures maintained at high and low oxygen tension together with analysis of tumour transcriptome indicates that lowering oxygen tension during cell culture may more allegedly reproduce tumour cell behaviour within GBM than standard culture conditions (e.g., atmospheric oxygen tension). Low oxygen culture conditions should be considered as a more appropriate model for further studies on glioblastoma pathology and therapy.

Surgical treatment of brainstem cavernomas using diffusion tensor imaging and diffusion tensor tractography.

INTRODUCTION: The aims of this study were to assess the prognosis of patients after a single haemorrhage from the cavernoma, and also in the case of rehaemorrhage, and to determine the indications for surgical treatment of brainstem cavernomas. MATERIAL AND METHODS: The study included a group of 35 patients with brainstem cavernomas, 23 women and 12 men aged 27 to 57 years (mean age 38.4). Up to 2005, MRI perfusion-weighted imaging/diffusion-weighted imaging had been carried out in 13 surgically treated patients. From 2005 onwards, the other 22 patients also underwent MRI diffusion tensor imaging and diffusion tensor tractography (DTI/DTT). DTI/DTT assessed the course of long fibre tracts. The course of the corticospinal tract, medial lemniscus and transverse pontine tracts was entered into the neuronavigation system. The surgical approach and the safe entry zone were determined based on the DTI/DTT. RESULTS: Our study showed that rehaemorrhage from a cavernoma depends on its size and volume. However, it is not related to its location. Based on the modified Rankin scale, the results of treatment of our patients after the first haemorrhage were better compared to the assessment after another haemorrhage. Complete resection was performed in 32 cases (91%) and partial resection in the remaining three (9%). Two patients underwent another surgery after several years due to partial resection. One patient presented with another haemorrhage after three years. New deficits developed postoperatively. Already existing deficits were exacerbated, but gradually resolved. Symptoms of cerebellar dysfunction and cranial nerve injury (including respiratory disorders) were the most difficult to resolve. CONCLUSIONS: Patients with brainstem cavernomas should undergo surgical treatment after their first haemorrhage, especially in the case of a large cavernoma. DTI/DTT should be used to determine the trajectory to the cavernoma, particularly to the deep cavernoma, and to determine the safe entry zone. Total resection of the cavernoma should be performed even where this means that reoperation is required.

Comprehensive assessment of a nationwide simulation-based course for artificial life support.

BACKGROUND: Successful implementation of medical technologies applied in life-threatening conditions, including extracorporeal membrane oxygenation (ECMO) requires appropriate preparation and training of medical personnel. The pandemic has accelerated the creation of new ECMO centers and has highlighted continuous training in adapting to new pandemic standards. To reach high standards of patients' care, we created the first of its kind, National Education Centre for Artificial Life Support (NEC-ALS) in 40 million inhabitants' country in the Central and Eastern Europe (CEE). The role of the Center is to test and promote the novel or commonly used procedures as well as to develop staff skills on management of patients needing ECMO. METHOD: In 2020, nine approved and endorsed by ELSO courses of "Artificial Life Support with ECMO" were organized. Physicians participated in the three-day high-fidelity simulation-based training that was adapted to abide by the social distancing norms of the COVID-19 pandemic. Knowledge as well as crucial cognitive, behavioral and technical aspects (on a 5-point Likert scale) of management on ECMO were assessed before and after course completion. Moreover, the results of training in mechanical chest compression were also evaluated. RESULTS: There were 115 participants (60% men) predominantly in the age of 30-40 years. Majority of them (63%) were anesthesiologists or intensivists with more than 5-year clinical experience, but 54% had no previous ECMO experience. There was significant improvement after the course in all cognitive, behavioral, and technical self-assessments. Among aspects of management with ECMO that all increased significantly following the course, the most pronounced was related to the technical one (from approximately 1.0 to more 4.0 points). Knowledge scores significantly increased post-course from 11.4 ± SD to 13 ± SD (out of 15 points). The quality of manual chest compression relatively poor before course improved significantly after training. CONCLUSIONS: Our course confirmed that simulation as an educational approach is invaluable not only in training and testing of novel or commonly used procedures, skills upgrading, but also in practicing very rare cases. The implementation of the education program during COVID-19 pandemic may be helpful in founding specialized Advanced Life Support centers and teams including mobile ones. The dedicated R&D Innovation Ecosystem established in the "ECMO for Greater Poland" program, with developed National Education Center can play a crucial role in the knowledge and know-how transfer but future research is needed.

Wall shear stress gradient is independently associated with middle cerebral artery aneurysm development: a case-control CFD patient-specific study based on 77 patients.

BACKGROUND: Previously published computational fluid dynamics (CFD) studies regarding intracranial aneurysm (IA) formation present conflicting results. Our study analysed the involvement of the combination of high wall shear stress (WSS) and a positive WSS gradient (WSSG) in IA formation. METHODS: We designed a case-control study with a selection of 38 patients with an unruptured middle cerebral artery (MCA) aneurysm and 39 non-aneurysmal controls to determine the involvement of WSS, oscillatory shear index (OSI), the WSSG and its absolute value (absWSSG) in aneurysm formation based on patient-specific CFD simulations using velocity profiles obtained from transcranial colour-coded sonography. RESULTS: Among the analysed parameters, only the WSSG had significantly higher values compared to the controls (11.05 vs - 14.76 [Pa/mm], P = 0.020). The WSS, absWSSG and OSI values were not significantly different between the analysed groups. Logistic regression analysis identified WSS and WSSG as significant co-predictors for MCA aneurysm formation, but only the WSSG turned out to be a significant independent prognosticator (OR: 1.009; 95% CI: 1.001-1.017; P = 0.025). Significantly more patients (23/38) in the case group had haemodynamic regions of high WSS combined with a positive WSSG near the bifurcation apex, while in the control group, high WSS was usually accompanied by a negative WSSG (14/39). From the analysis of the ROC curve for WSSG, the area under the curve (AUC) was 0.654, with the optimal cut-off value -0.37 Pa/mm. The largest AUC was recognised for combined WSS and WSSG (AUC = 0.671). Our data confirmed that aneurysms tend to form near the bifurcation apices in regions of high WSS values accompanied by positive WSSG. CONCLUSIONS: The development of IAs is determined by an independent effect of haemodynamic factors. High WSS impacts MCA aneurysm formation, while a positive WSSG mainly promotes this process.

Prophylactic use of dural tenting sutures in elective craniotomies in adults-is it necessary? A study protocol for a multicentre, investigator- and participant-blinded randomised, parallel-group, non-inferiority trial.

BACKGROUND: In the early days of neurosurgery, extradural haemorrhages (EDHs) contributed to a high mortality rate after craniotomies. Almost a century ago, Walter Dandy reported dural tenting sutures as an effective way to prevent postoperative EDH. Over time, his technique gained in popularity and significance to finally become a neurosurgical standard. Yet, several retrospective reports and one prospective report have questioned the ongoing need for dural tenting sutures. Dandy's explanation that the haemostasis observed under hypotensive conditions is deceiving and eventually causes EDH may be obsolete. Today, proper intra- and postoperative care, including maintenance of normovolemia and normotension and the use of modern haemostatic agents, may be sufficient for effective haemostasis. Thus, there is a fundamental need to evaluate the necessity of dural tenting sutures in a solid, unbiased, evidence-based manner. METHODS: This study is designed as a randomised, multicentre, double-blinded, controlled interventional trial with 1:1 allocation. About one half of the participants will undergo craniotomy without dural tenting sutures and will be considered an intervention group. The other half will undergo craniotomy with these sutures. Both groups will be followed clinically and radiologically. The primary outcome is reoperation due to extradural haematoma. Secondary outcomes aim to evaluate the impact of dural tenting sutures on mortality, readmission risk, postoperative headaches, size of extradural collection, cerebrospinal fluid leak risk and the presence of any new neurological deficit. The study protocol follows the SPIRIT 2013 statement. DISCUSSION: It is possible that many neurosurgeons around the globe are tenting the dura in elective craniotomies which brings no benefit and only extends the operation. Unfortunately, there is not enough data to support or reject this technique in modern neurosurgery. This is the first study that may produce strong, evidence-based recommendations on using dural tenting sutures. TRIAL REGISTRATION, ETHICS AND DISSEMINATION: The Bioethics Committee of the Medical University of Warsaw approved the study protocol (KB/106/2018). The trial is registered at http://www.clinicaltrials.gov ( NCT03658941 ) on September 6, 2018. The findings of this trial will be submitted to a peer-reviewed neurosurgical journal. Abstracts will be submitted to relevant national and international conferences. TRIAL STATUS: Protocol version and date: version 1.5, 14.01.2020 First recruitment: September 7, 2018 Estimated recruitment completion: September 1, 2021.

Variations in Values of State, Response Entropy and Haemodynamic Parameters Associated with Development of Different Epileptiform Patterns during Volatile Induction of General Anaesthesia with Two Different Anaesthetic Regimens Using Sevoflurane in Comparison with Intravenous Induct: A Comparative Study.

BACKGROUND AND OBJECTIVES: Raw electroencephalographic (EEG) signals are rarely used to monitor the depth of volatile induction of general anaesthesia (VIGA) with sevoflurane, even though EEG-based indices may show aberrant values. We aimed to identify whether response (RE) and state entropy (SE) variations reliably reflect the actual depth of general anaesthesia in the presence of different types of epileptiform patterns (EPs) in EEGs during induction of general anaesthesia. MATERIALS AND METHODS: A randomized, prospective clinical study was performed with 60 patients receiving VIGA using sevoflurane with the increasing concentrations (group VIMA) or the vital capacity (group VCRII) technique or an intravenous single dose of propofol (group PROP). Facial electromyography (fEMG), fraction of inspired sevoflurane (FiAA), fraction of expired sevoflurane (FeAA), minimal alveolar concentration (MAC) of sevoflurane, RE and SE, and standard electroencephalographic evaluations were performed in these patients. RESULTS: In contrast to periodic epileptiform discharges, erroneous SE and RE values in the patients' EEGs were associated with the presence of polyspikes (PS) and rhythmic polyspikes (PSR), which were more likely to indicate toxic depth rather than false emergence from anaesthesia with no changes in the FiAA, FeAA, and MAC of sevoflurane. CONCLUSION: Calculated RE and SE values may be misleading during VIGA when EPs are present in patients' EEGs. During VIGA with sevoflurane, we recommend monitoring raw EEG data in scientific studies to correlate it with potentially erroneous RE and SE values and the end-tidal concentration of sevoflurane in everyday clinical practice, when monitoring raw EEG is not available, because they can mislead anaesthesiologists to reduce sevoflurane levels in the ventilation gas and result in unintentional true emergence from anaesthesia. Further studies are required to investigate the behaviour of EEG-based indices during rapid changes in sevoflurane concentrations at different stages of VIGA and the influence of polyspikes and rhythmic polyspikes on the transformation of EEG signals into a digital form.

Morphological and Hemodynamic Risk Factors for Middle Cerebral Artery Aneurysm: a Case-Control Study of 190 Patients.

This study analyzed morphometric and hemodynamic parameters of aneurysmal and non-aneurysmal middle cerebral artery (MCA) bifurcations and their relationship with optimal values derived from the principle of minimum work (PMW). The study included 96 patients with MCA aneurysm and 94 controls. Aneurysm patients presented with significantly higher values of the radius and cross-sectional area of the MCA trunk, angle between the post-bifurcation branches (α angle) and volume flow rate (VFR) and had significantly lower values of junction exponent and pulsatility index than the controls. The Φ1 and Φ2 angles (angles between the MCA trunk axis and the larger and smaller branch, respectively) and α angle in all groups were significantly larger than the optimal PMW-derived angles. The most important independent predictors of MCA aneurysm were junction exponent (odds ratio, OR = 0.42), α angle (OR = 1.07) and VFR (OR = 2.36). Development of cerebral aneurysms might be an independent effect of abnormalities in hemodynamic and morphometric factors. The risk of aneurysm increased proportionally to the deviation of morphometric parameters of the bifurcation from their optimal PMW-derived values. The role of bifurcation angle in aneurysm development needs to be explained in future research as the values of this parameter in both aneurysm patients and non-aneurysmal controls in were scattered considerably around the PMW-derived optimum.

Influence of infiltration anaesthesia on perioperative outcomes following lumbar discectomy under surgical pleth index-guided general anaesthesia: A preliminary report from a randomised controlled prospective trial.

PURPOSE: Severe postoperative pain (SPP) may occur after lumbar discectomy. To prevent SPP and reduce rescue opioid consumption, infiltration anaesthesia (IA) has been combined with general anaesthesia (GA). This study verified how GA combined with IA facilitated intra- and postoperative demand for opioids and affected the incidence of SPP in patients subjected to open lumbar discectomy. MATERIALS/METHODS: Ninety-nine patients undergoing lumbar discectomy under GA with Surgical Pleth Index (SPI)-guided fentanyl (FNT) administration were randomly assigned to receive IA combined with either 0.2% bupivacaine (BPV) or 0.2% ropivacaine (RPV) with FNT 50 µg and compared with controls (BF, RF, and C groups, respectively). RESULTS: Ninety-four patients were included in the final analysis. Adjusted according to SPI, total intraoperative FNT dosages did not differ between the study groups (p = 0.23). The proportion of patients who reported SPP was the highest in group C (41.9%) than in the RF (12.9%) and BF groups (31.3%) (p < 0.05). Mild pain was experienced by 67.7%, 53.1% and 32.3% of patients from the RF, BF and C groups, respectively (p < 0.01). Morphine requirement was the highest in the control group (7.1 ± 5.9 mg), followed by the RF (2.7 ± 5.3 mg) and BF groups (4 ± 4.9 mg) (p < 0.05). CONCLUSIONS: IA using RPV/FNT mixture significantly reduced SPP and postoperative demand for morphine in patients subjected to lumbar discectomy under GA.

Hadad-Bassagasteguy flap in skull base reconstruction - current reconstructive techniques and evaluation of criteria used for qualification for harvesting the flap.

INTRODUCTION: Cerebrospinal fluid (CSF) leakage is a common consequence or complication in the operations of skull base tumors. The Hadad-Bassagasteguy flap (HBF) is the most common local flap used in the reconstruction of the meninges. It is a nasoseptal flap (NSF) vascularized by the sphenopalatine artery (SPA). Improvement of the already existing techniques is necessary. AIM: To present our experience in HBF and to evaluate the criteria used for qualification (relative and absolute indications) for the NSF reconstructive technique. MATERIAL AND METHODS: The retrospective study included 25 patients who underwent expanded endonasal approach (EEA) operations with the NSF. The correctness of qualification based on our own criteria was assessed. The most important modifications of the original HBF as well as the reasons for failures are discussed. RESULTS: There were 12 relative and 13 absolute indications for NSF harvesting. In 2 cases no anticipated CSF leakage was observed. No complications were reported. CONCLUSIONS: Skull base reconstruction with HBF and its various modifications is a highly effective technique. Absolute indications for NSF harvesting prior to resection are: reoperations in the case of a previous open approach, preoperative CSF leakage, intradural localization of a tumor related to its etiopathogenesis, suspicion of intradural diffusion of a neoplasm in magnetic resonance imaging if the etiopathogenesis cannot clarify the tumor's relation to the meninges. Relative indications concern mostly pituitary macroadenomas of at least 2.5 cm in diameter.

Necessity of dural tenting sutures in modern neurosurgery: protocol for a systematic review.

INTRODUCTION: The ongoing need for dural tenting sutures in a contemporary neurosurgical practice has been questioned in the literature for over two decades. In the past, these sutures were supposed to prevent blood collecting in the potential space between the skull and the dura by elevating the latter. Theoretically, with modern haemostasis and proper postoperative care, this technique should not be necessary and the surgery time can be shortened. Unfortunately, there is no evidence-based proof to either support or reject this hypothesis. METHODS AND ANALYSIS: The systematic review will be performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement and The Cochrane Handbook for Systematic Reviews of Interventions. Eight electronic databases of peer-reviewed journals will be searched, as well as other sources. Eligible articles will be assessed against inclusion criteria. The intervention is not tenting the dura and this will be compared with the usual dural tenting sutures. Where possible, 'summary of findings' tables will be generated. ETHICS AND DISSEMINATION: Ethical committee approval is not required for a systematic review protocol. Findings will be presented at international neurosurgical conferences and published in a peer-reviewed medical journal. PROSPERO REGISTRATION NUMBER: CRD42018097089.

Coincidence of craniocerebral and craniofacial injuries.

PURPOSE: To determine the incidence of craniocerebral injuries in patients who experienced upper facial or midfacial traumas associated with the disorders of consciousness. To find which types of craniofacial traumas predisposed to craniocerebral injuries. To analyze a relationship between the site of the force application and the type of resultant craniocerebral injury. MATERIALS AND METHODS: The study included 3,481 patients with upper facial and midfacial traumas. All 425 patients with craniofacial traumas and disorders of consciousness at the time of the event or hospital admission, were qualified for computed tomography (CT) of the head. RESULTS: In 85/425 patients (20%), 70 men and 15 women (age 14-71 years), craniofacial trauma coincided with a craniocerebral injury. Upper facial dislocation and zygomatic-orbital-maxillary complex fracture significantly more often co-existed with skull, dura mater or cranial nerve injuries, and zygomatico-orbital fracture with the injuries of the brain. Application of force both centrally and laterally to the horizontal plane predisposed to skull, dura mater and cranial nerve injuries. CONCLUSION: The recommendation to perform head CT in each patient with craniofacial trauma who experienced the disorders of consciousness is as simple as possible, yet provides high diagnostic sensitivity, facilitating proper management at initial stages post-injury.

Neuropsychological assessment of patients undergoing surgery due to low-grade glioma involving the supplementary motor area.

OBJECTIVE: The aim of the study was to establish the usefulness of various neuropsychological tests in patients undergoing surgery due to low-grade glioma (LGG) involving supplementary motor area (SMA). PATIENTS AND METHODS: 21 patients diagnosed with LGG involving the SMA underwent, before and after surgery, screening tests (Mini Mental State Examination - MMSE, Montreal Cognitive Assessment - MoCA and Frontal Assessment Battery - FAB), tests to assess language functions (Addenbrook's Cognitive Examination-III - ACE-III, phonetic fluency tests and semantic fluency tests), tests to assess memory functions (Rey's 15-word test - RAVLT and Diagnostic Test for Brain Damage by Hillers- DCS), tests to assess executive functions (Wisconsin Card Sorting Test - WCST, Ruff Figural Fluency Test - RFFT and Trail Making Test). RESULTS: Before surgery, in the screening tests the patients obtained below normal scores in the MoCA test only. After surgery, the scores of such tests were significantly worse than the scores before surgery, while the MMSE test scores continued to be within the normal range. In phonetic and semantic fluency tests, the patients obtained worse scores, both before and after surgery. The differences in the test scores between the two periods, i.e. before and after surgery, were statistically significant. Although the patients obtained worse scores both before and after surgery in the ACE III test, the differences in the test scores were not statistically significant. The scores obtained in all tests assessing the executive and memory functions before and after surgery were within the normal range. The scores in such tests (except the WCCT) dropped significantly after surgery. CONCLUSIONS: Patients diagnosed with LGG involving the SMA reveal the impairment of cognitive functions, in particular language functions. After surgery, a significant impairment of all elementary cognitive functions, such as attention, memory, language and executive functions and complex cognitive functions, occurs. The most sensitive tests to detect cognitive disorders, executive dysfunctions and speech disturbances in patients undergoing surgery due to glioma include the MoCA, FAB and Phonetic and Semantic Fluency Tests.

Surgical treatment and prognosis of adult patients with brainstem gliomas.

The paper presents 47 adult patients who were surgically treated due to brainstem gliomas. Thirteen patients presented with contrast-enhancing Grades III and IV gliomas, according to the WHO classification, 13 patients with contrast-enhancing tumours originating from the glial cells (Grade I; WHO classification), 9 patients with diffuse gliomas, 5 patients with tectal brainstem gliomas and 7 patients with exophytic brainstem gliomas. During the surgical procedure, neuronavigation and the diffusion tensor tractography (DTI) of the corticospinal tract were used with the examination of motor evoked potentials (MEPs) and somatosensory evoked potentials (SSEPs) with direct stimulation of the fundus of the fourth brain ventricle in order to define the localization of the nuclei of nerves VII, IX, X and XII. Cerebellar dysfunction, damage to cranial nerves and dysphagia were the most frequent postoperative sequelae which were also the most difficult to resolve. The Karnofsky score established preoperatively and the extent of tumour resection were the factors affecting the prognosis. The mean time of progression-free survival (14 months) and the mean survival time after surgery (20 months) were the shortest for malignant brainstem gliomas. In the group with tectal brainstem gliomas, no cases of progression were found and none of the patients died during the follow-up. Some patients were professionally active. Partial resection of diffuse brainstem gliomas did not prolong the mean survival above 5 years. However, some patients survived over 5 years in good condition.

Type of cardioplegic solution as a factor influencing the clinical outcome of open-heart congenital procedures.

INTRODUCTION: Cardioplegia is one of the most important modalities of myocardial protection during heart surgery. AIM: To assess the impact of blood cardioplegia on postoperative variables, in comparison with two types of crystalloid cardioplegic solutions during pediatric heart surgery. MATERIAL AND METHODS: One thousand one hundred and twenty-nine patients underwent surgical correction of congenital heart disease with cardioplegia administration between 2006 and 2012. Nonlinear regression models of postoperative low cardiac output syndrome (LCOS) incidence, catecholamine index and total complication count were developed using a genetic algorithm. The Akaike information criterion was applied for selection of the best model. The following explanatory variables were evaluated: cardioplegia type (ST - Saint Thomas, n = 440; FR - Fresenius, n = 432; BL - Calafiore, n = 257), congenital heart diseases (CHD) type, age, sex, genetic disorder presence, body surface area (BSA), cardiopulmonary bypass (CBP) time, aortic cross-clamp time, operation urgency, redo surgery, surgeon. RESULTS: Low cardiac output syndrome presence and higher than average catecholamine indexes were negatively influenced by use of crystalloid cardioplegia (ST or FR), presence of specific CHDs, redo surgery and prolonged CBP time. Increased complication count was related to: crystalloid cardioplegia, presence of specific CHDs, redo surgery, urgency of operation, operation time and CBP time. Higher BSA had a protective effect against higher catecholamine index and increased complication count. Older age was protective against LCOS. CONCLUSIONS: Cardioplegic solutions type influences postoperative variables in children after heart surgery by the negative impact of crystalloid cardioplegia. Blood cardioplegia presents potential advantages for patients - its application may reduce the incidence of low cardiac output syndrome and related complications.

Surgical treatment of adult patients with thalamic tumors with the aid of tractography, fMRI, transcranial electrical stimulation and direct electrical stimulation of the subcortical white matter.

The aim of investigation was to assess treatment outcomes in adult patients with thalamic tumors, operated on with the aid of tractography (DTI) and monitoring of motor evoked potentials (MEPs) generated due to transcranial electrical stimulation (TES) and direct electrical stimulation (DES) of the subcortical white matter. 38 subsequent patients with thalamic tumors were operated on using tractography (DTI)-integrated neuronavigation, transcranial electrical stimulation (TES) and direct electrical stimulation (DES). The volumetric method was used to calculate pre- and postoperative tumor volume. Total tumor resection (100%) was performed in 18 (47%) patients, subtotal in 9 (24%) (mean extent of resection -89.4%) and partial in 11 (29%) patients (mean extent of resection -77.18%). The mean extent of resection for all surgical patients was 86.5%. Two (5.2%) patients died postoperatively. Preoperative hemiparesis was present in 18 (47%) patients. Postoperative hemiparesis was observed in 11 (29%) patients of whom only in 5 (13%) new paresis was noted due to surgical intervention. In patients with hemiparesis significantly more frequently larger tumor volume was detected preoperatively. Low mean normal fractional anisotropy (nFA) values in the internal capsule were observed statistically significantly more frequently in patients with preoperative hemiparesis as compared to the internal capsule of the unaffected hemisphere. Transcranial electrical stimulation helps to predict postoperative paresis of extremities. Direct electrical stimulation is an effective tool for intraoperative localization of the internal capsule thus helping to avoid postoperative deficit. In patients with tumor grade I and II the median time to tumor progression was 36 months. In the case of patients with grades III and IV it was 14 months. The median survival time in patients with grades I and II it was 60 months. In patients with grades III and IV it was 18 months. Basing on our results, patients with glioma grade I/II according to WHO classification are the best candidates for surgical treatment of thalamic tumors. In this group of the patients more often resection is radical, median time to progression and survival time are longer than in patients with gliomas grade III and IV. Within a 7-year follow-up none of the patients with GI/GII grade glioma died.

BEST Life-"Bringing ECMO Simulation To Life"-How Medical Simulation Improved a Regional ECMO Program.

The implemented "ECMO for Greater Poland" program takes full advantage of the ECMO (extracorporeal membrane oxygenation) perfusion therapy to promote health for 3.5 million inhabitants in the region. The predominant subjects of implementation are patients with hypothermia, with severe reversible respiratory failure (RRF), and treatment of other critical states leading to heart failure such as sudden cardiac arrest, cardiogenic shock or acute intoxication. Finally, it promotes donation after circulatory death (DCD) strategy in selected organ donor cases. ECMO enables recovery of organs' function after unsuccessful lifesaving treatment. Because this organizational model is complex and expensive, we use advanced high-fidelity medical simulation to prepare for real-life implementation. During the first four months, we performed scenarios mimicking "ECMO for DCD," "ECMO for ECPR (extended cardiopulmonary resuscitation)," "ECMO for RRF" and "ECMO in hypothermia." It helped to create algorithms for aforementioned program arms. In the following months, three ECMO courses for five departments in Poznan (capitol city of Greater Poland) were organized and standardized operating procedures for road ECMO transportation within Medical Emergency System were created. Soon after simulation program, 38 procedures with ECMO perfusion therapy including five road transportations on ECMO were performed. The Maastricht category II DCD procedures were done four times on real patients and in two cases double successful kidney transplantations were carried out for the first time in Poland. ECMO was applied in two patients with hypothermia, nine adult patients with heart failure, and five with RRF, for the first time in the region. In the pediatric group, ECMO was applied in four patients with RRF and 14 with heart failure after cardiac surgery procedures. Additionally, one child was treated successfully following 200 km-long road transport on ECMO. We achieved good and promising results especially in VV ECMO therapy. Simulation-based training enabled us to build a successful procedural chain, and to eliminate errors at the stage of identification, notification, transportation, and providing ECMO perfusion therapy. We discovered the important role of medical simulation, not only to test the medical professional's skills, but also to promote ECMO therapy in patients with critical/life-threatening states. Moreover, it also resulted in increase of the potential organ pool from DCD in the Greater Poland region.

Effects of Polylactide Copolymer Implants and Platelet-Rich Plasma on Bone Regeneration within a Large Calvarial Defect in Sheep.

The aim of this study was to verify whether L-lactide/DL-lactide copolymer 80/20 (PLDLLA) and platelet-rich plasma (PRP) trigger bone formation within critical-sized calvarial defects in adult sheep (n = 6). Two craniectomies, each ca. 3 cm in diameter, were created in each animal. The first craniectomy was protected with an inner polylactide membrane, filled with PRP-polylactide granules, and covered with outer polylactide membrane. The second control craniectomy was left untreated. The animals were euthanized at 6, 7, 17, 19, 33, and 34 weeks after surgery, and the quality and the rate of reossification were assessed histomorphometrically and microtomographically. The study demonstrated that application of implants made of PLDLLA 80/20 combined with an osteopromotive substance (e.g., PRP) may promote bone healing in large calvarial defect in sheep. These promising proof-of-concept studies need to be verified in the future on a larger cohort of animals and over a longer period of time in order to draw definitive conclusions.

Usefulness of intraoperative monitoring of oculomotor and abducens nerves during surgical treatment of the cavernous sinus meningiomas.

PURPOSE: We analyzed the usefulness and prognostic value of intraoperative monitoring for identification of the oculomotor (III) and the abducens (VI) nerve in patients with cavernous sinus meningiomas. MATERIAL/METHODS: 43 patients diagnosed with cavernous sinus meningiomas were divided according to their topography. Function of the nerves was scored on original clinical and neurophysiological scales. RESULTS: The percentage of nerves identified correctly with the monitoring was significantly higher (91% vs. 53% for nerve III and 70% vs. 23% for nerve VI, p<0.001). The fractions of nerves III and VI identified correctly by means of the monitoring were significantly higher in the case of tumors with intra- and extracavernous location (89% vs. 32%, p<0.01) and intracavernous tumors (80% vs. 20%, p<0.05), respectively. The quality of post-resection recording correlated with functional status of both the nerves determined 9 months after the surgery (R=0.51, p<0.001 for nerve III and R=0.57, p<0.01 for nerve VI). Even a trace or pathological response to the post-resection stimulation was associated with improved functional status (90% vs. 50%, p<0.05 for nerve III and 93% vs. 38%, p<0.01 for nerve VI). CONCLUSIONS: Neurophysiological monitoring of ocular motor nerves enables their intraoperative identification during resections of the cavernous sinus meningiomas. Intraoperative monitoring of nerve III is particularly important in the case of tumors with extra- and intracavernous location, and the monitoring of nerve VI in the case of intracavernous tumors. The outcome of the post-resection monitoring has prognostic value with regard to the clinical status of the nerves on long-term follow-up.