Intraoperative Neurophysiologic Monitoring in Predicting Dysphagia After Brainstem and Fourth Ventricle Surgery.

OBJECTIVE: Dysphagia represents the main complication of posterior fossa neurosurgery. Adequate diagnosis of this complication is warranted to prevent untimely extubation with subsequent aspiration. Intraoperative neurophysiologic monitoring (IONM) modalities may be used for this purpose. However, it is not known which IONM modality may be significant for diagnosis. This study aimed to define the most significant IONM modality for dysphagia prognostication after posterior fossa neurosurgery. METHODS: The analysis included 46 patients (34 with tumors of the fourth ventricle and 12 with brainstem localization) who underwent surgical excision of the tumor. Neurologic symptoms before and after neurosurgery were noted and magnetic resonance imaging with the subsequent volume estimation of the removed mass was performed, followed by an IONM findings analysis (mapping of the nucleus of the caudal cranial nerves [CN] and corticobulbar motor-evoked potentials [CoMEP]). RESULTS: Aggravation of dysphagia was noted in 24% of the patients, more often in patients with tumor localization in the fourth ventricle (26%) than in those with brainstem mass lesions (16%). Mapping of the caudal cranial nerve nuclei did not correlate with the dysfunction of these structures. CoMEP was significantly associated with the neurologic state of the CN. The decrease in CoMEP is a significant prognostic factor for postoperative bulbar symptoms appearance or aggravation. CONCLUSIONS: Mapping the CN is an important identification tool. The CoMEP modality should be used intraoperatively to determine the functional state of the CN and predict postoperative dysphagia.

Accuracy of Manual Intracranial Pressure Recording Compared to a Computerized High-Resolution System: A CENTER-TBI Analysis.

BACKGROUND: Monitoring intracranial pressure (ICP) and cerebral perfusion pressure (CPP) is crucial in the management of the patient with severe traumatic brain injury (TBI). In several institutions ICP and CPP are summarized hourly and entered manually on bedside charts; these data have been used in large observational and interventional trials. However, ICP and CPP may change rapidly and frequently, so data recorded in medical charts might underestimate actual ICP and CPP shifts. The aim of this study was to evaluate the accuracy of manual data annotation for proper capturing of ICP and CPP. For this aim, we (1) compared end-hour ICP and CPP values manually recorded (MR) with values recorded continuously by computerized high-resolution (HR) systems and (2) analyzed whether MR ICP and MR CPP are reliable indicators of the burden of intracranial hypertension and low CPP. METHODS: One hundred patients were included. First, we compared the MR data with the values stored in the computerized system during the first 7 days after admission. For this point-to-point analysis, we calculated the difference between end-hour MR and HR ICP and CPP. Then we analyzed the burden of high ICP (> 20 mm Hg) and low CPP (< 60 mm Hg) measured by the computerized system, in which continuous data were stored, compared with the pressure-time dose based on end-hour measurements. RESULTS: The mean difference between MR and HR end-hour values was 0.02 mm Hg for ICP (SD 3.86 mm Hg) and 1.54 mm Hg for CPP (SD 8.81 mm Hg). ICP > 20 mm Hg and CPP < 60 mm Hg were not detected by MR in 1.6% and 5.8% of synchronized measurements, respectively. Analysis of the pathological ICP and CPP throughout the recording, however, indicated that calculations based on manual recording seriously underestimated the ICP and CPP burden (in 42% and 28% of patients, respectively). CONCLUSIONS: Manual entries fairly represent end-hour HR ICP and CPP. However, compared with a computerized system, they may prove inadequate, with a serious risk of underestimation of the ICP and CPP burden.

Giant Middle Cerebral Artery Aneurysms: A 55-Patient Series.

BACKGROUND: The treatment of middle cerebral artery (MCA) giant aneurysms (GAs) represents a challenging task. METHODS: The data for 55 patients treated for MCA GA (≥25 mm) at the N.N. Burdenko NMRCN between 2010 and 2019 were analyZed. RESULTS: The GAs were located in the M1 segment in 11 (20%) patients, MCA bifurcation in 33 (60%), M2 in 7 (12.7%), and M3 in 4 (7.3%). There were 32 (58.2%) saccular and 23 (41.8%) fusiform GAs. MCA GAs were treated with neck clipping (50.9%), clipping with the artery lumen formation (3.6%), bypass surgeries (34.5%), wrapping (3.6%), and endovascular surgery (7.3%). A worsening of the neurologic state in the perioperative period was observed in 50.9% of patients. The complete closure of GA was achieved in 78.2%. Surgery-related mortality was 1.8%. The long-term outcome was favorable in 76.9% of patients. Surgery-related and disease-related plus treatment failures-related mortality was 9.6%. CONCLUSIONS: Microsurgical clipping and bypass surgery are the main operative interventions for MCA GA treatment. These operations are technically complex and are followed by a relatively high percentage of complications. The main tasks that require further investigations are the introduction of new precise diagnostic methods for the collateral circulation assessment in the cortical MCA branches, the perfection of the algorithm for the bypass selection, and investigation of the long-term results of the endovascular and combined treatments. It is of major importance to thoroughly observe the patients long-term after the surgery and ensure the possibility for further angiographic studies.

Severe vancomycin-induced thrombocytopenia in a patient with meningitis.

Vancomycin is a widely used antibiotic and rarely can cause drug-induced thrombocytopenia. A patient with hospital-acquired meningitis after neurosurgery was treated with systemic and intrathecal vancomycin. On 9th day of antibiotic treatment, the patient's platelets dropped to 0.68×109/L. Multiple platelet transfusions had minimal influence on platelet count. After cessation of vancomycin therapy, platelets returned to normal values without any additional interventions. Diagnosis of vancomycin-induced thrombocytopenia was confirmed by detection of drug-dependent antiplatelet IgG antibodies.

Brain Temperature Influences Intracranial Pressure and Cerebral Perfusion Pressure After Traumatic Brain Injury: A CENTER-TBI Study.

BACKGROUND: After traumatic brain injury (TBI), fever is frequent. Brain temperature (BT), which is directly linked to body temperature, may influence brain physiology. Increased body and/or BT may cause secondary brain damage, with deleterious effects on intracranial pressure (ICP), cerebral perfusion pressure (CPP), and outcome. METHODS: Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI), a prospective multicenter longitudinal study on TBI in Europe and Israel, includes a high resolution cohort of patients with data sampled at a high frequency (from 100 to 500 Hz). In this study, simultaneous BT, ICP, and CPP recordings were investigated. A mixed-effects linear model was used to examine the association between different BT levels and ICP. We additionally focused on changes in ICP and CPP during the episodes of BT changes (Δ BT ≥ 0.5 °C lasting from 15 min to 3 h) up or downward. The significance of ICP and CPP variations was estimated with the paired samples Wilcoxon test (also known as Wilcoxon signed-rank test). RESULTS: Twenty-one patients with 2,435 h of simultaneous BT and ICP monitoring were studied. All patients reached a BT of 38 °C and experienced at least one episode of ICP above 20 mm Hg. The linear mixed-effects model revealed an association between BT above 37.5 °C and higher ICP levels that was not confirmed for lower BT. We identified 149 episodes of BT changes. During BT elevations (n = 79) ICP increased, whereas CPP was reduced; opposite ICP and CPP variations occurred during episodes of BT reduction (n = 70). All these changes were of moderate clinical relevance (increase of ICP of 4.5 and CPP decrease of 7.5 mm Hg for BT rise, and ICP reduction of 1.7 and CPP elevation of 3.7 mm Hg during BT defervescence), even if statistically significant (p < 0.0001). It has to be noted, however, that a number of therapeutic interventions against intracranial hypertension was documented during those episodes. CONCLUSIONS: Patients after TBI usually develop BT > 38 °C soon after the injury. BT may influence brain physiology, as reflected by ICP and CPP. An association between BT exceeding 37.5 °C and a higher ICP was identified but not confirmed for lower BT ranges. The relationship between BT, ICP, and CPP become clearer during rapid temperature changes. During episodes of temperature elevation, BT seems to have a significant impact on ICP and CPP.

Optic Nerve Sheath Diameter is not Related to Intracranial Pressure in Subarachnoid Hemorrhage Patients.

BACKGROUND: Intracranial pressure (ICP) monitoring is essential after subarachnoid hemorrhage (SAH) to prevent secondary brain insults and to tailor individualized treatments. Optic nerve sheath diameter (ONSD), measured using ultrasound (US), could serve as a noninvasive bedside tool to estimate ICP, avoiding the risks of hemorrhage or infection related to intracranial catheters. The aims of this study were twofold: first, to explore the reliability of US for measuring ONSD; second, to establish whether the US-ONSD can be considered a proxy for ICP in SAH patients early after bleeding. For the first aim, we compared the ONSD measurements given by magnetic resonance imaging (MRI-ONSD) with the US-ONSD findings. For the second aim, we analyzed the relationship between US-ONSD measurements and ICP values. METHODS: Adult patients with diagnosis of aneurysmal SAH and external ventricular drainage system (EVD) were included. Ten patients were examined by MRI to assess ONSD, and the results were compared to the diameter given by US. In 20 patients, the US-ONSD values were related to ICP measured simultaneously through EVD. In ten of these patients, we explored the changes in the US-ONSD at the time of controlled and fairly rapid changes in ICP after cerebrospinal fluid (CSF) drainage. RESULTS: US-ONSD measurements at the bedside were accurate, very similar to the diameters measured by MRI (the mean difference in the Bland-Altman plot was 0.08 mm, 95% limits of agreement: - 1.13; + 1.23 mm). No clear relationship was detectable between the ICP and US-ONSD, and a linear regression model showed an angular coefficient very close to 0 (p > 0.05). US-ONSD and ICP values were in agreement after CSF drainage and shifts in ICP in a limited number of patients. CONCLUSIONS: US-ONSD measurement does not accurately estimate ICP in SAH patients in the intensive care unit.

Changing care pathways and between-center practice variations in intensive care for traumatic brain injury across Europe: a CENTER-TBI analysis.

PURPOSE: To describe ICU stay, selected management aspects, and outcome of Intensive Care Unit (ICU) patients with traumatic brain injury (TBI) in Europe, and to quantify variation across centers. METHODS: This is a prospective observational multicenter study conducted across 18 countries in Europe and Israel. Admission characteristics, clinical data, and outcome were described at patient- and center levels. Between-center variation in the total ICU population was quantified with the median odds ratio (MOR), with correction for case-mix and random variation between centers. RESULTS: A total of 2138 patients were admitted to the ICU, with median age of 49 years; 36% of which were mild TBI (Glasgow Coma Scale; GCS 13-15). Within, 72 h 636 (30%) were discharged and 128 (6%) died. Early deaths and long-stay patients (> 72 h) had more severe injuries based on the GCS and neuroimaging characteristics, compared with short-stay patients. Long-stay patients received more monitoring and were treated at higher intensity, and experienced worse 6-month outcome compared to short-stay patients. Between-center variations were prominent in the proportion of short-stay patients (MOR = 2.3, p < 0.001), use of intracranial pressure (ICP) monitoring (MOR = 2.5, p < 0.001) and aggressive treatments (MOR = 2.9, p < 0.001); and smaller in 6-month outcome (MOR = 1.2, p = 0.01). CONCLUSIONS: Half of contemporary TBI patients at the ICU have mild to moderate head injury. Substantial between-center variations exist in ICU stay and treatment policies, and less so in outcome. It remains unclear whether admission of short-stay patients represents appropriate prudence or inappropriate use of clinical resources.