Experimental-design Specific Changes in Spontaneous EEG and During Intermittent Photic Stimulation by High Definition Transcranial Direct Current Stimulation.

Electroencephalography (EEG) as a biomarker of neuromodulation by High Definition transcranial Direct Current Stimulation (HD-tDCS) offers promise as both techniques are deployable and can be integrated into a single head-gear. The present research addresses experimental design for separating focal EEG effect of HD-tDCS in the '4-cathode × 1-anode' (4 × 1) montage over the left motor area (C3). We assessed change in offline EEG at the homologous central (C3, C4), and occipital (O1, O2) locations. Interhemispheric asymmetry was accessed for background EEG at standard frequency bands; and for the intermittent photic stimulation (IPS). EEG was compared post- vs pre-intervention in three HD-tDCS arms: Active (2 mA), Sham (ramp up/down at the start and end), and No-Stimulation (device was not powered), each intervention lasting 20 min. The asymmetric background EEG changes were only in the central areas with right-side amplitude spectra prevalence, most pronounced in the no-stimulation arm, where they depended on comparison time-points and were consistent with markers of transition between drowsiness and vigilance - bilateral decrease in the delta and asymmetric central increase in the alpha and beta1 bands. For the active arm, similar but less pronounced changes occurred in the alpha band. In contrast, responses to IPS developed similar asymmetric amplitude increase at four harmonics of the IPS of 3 Hz only in the active arm, against a background of a brain-wide symmetric increase in both active and sham arms. Our protocols and analyses suggest methodological caveats for how EEG of tDCS studies could be conducted to isolate putative brain polarization outcomes.

[About rare causes of the loss of hearing].

The present paper reports a clinical case of local syphilitic meningoencephalitis known as Argyll-Robertson syndrome and manifested in the form of acute sensorineural loss of hearing. The patient was a 46 year old resident of the city of Irkutsk. He experienced the sharp impairment of hearing involving both ears with the accompanying feeling of dizziness, disturbed orientation of the locomotorbehaviour, the lurching gate, subfebrility, the loss of the ability to speak and write. The diagnosis was based on the presence of anisocoria, the absence of consensual pupillary reaction to the light, weak atropine action on the pupils, well expressed positive results of the VRDL (blood) and RW (liquor) tests, an enhanced signal from the left temporal region in the T-2 regime during MRI, positive hearing dynamics within 12 hours after the onset of anti-inflammatory, antibacterial and infusion therapy. The specific feature of the clinical case being considered is differential diagnostics was performed with the purpose of distinguishing it from otogenic brain abscess associated with chronic left-hand mesotympanitis.

[Effect of succinate-containing solution on the level of metabolism during perioperative period in children].

DESIGN: A randomized prospective study. PATIENTS AND METHODS: The study included 87 children aged from 5 to 18, ASA I-II. The patients were divided into two groups. We assessed the impact of reamberin 1.5% (succinate-containing infusion solution) on the level of metabolism and recovery after surgery in patients of main group (n = 44) and control group (n = 43) during different surgeries. All patients received general anaesthesia with sevoflurane, fentanyl, and rocuronium. RESULTS: Reamberin 1.5% promotes to increase the level of basal metabolism in the early postoperative period, decreases the duration of awakening periods, improves recovery of motor activity and adequate breathing.

[Haemodynamics during kidney transplantation and general anaesthesia in combination with epidural block and without it in pediatric patients].

RESEARCH OBJECTIVE: To compare haemodynamic effects of general anaesthesia in combination with epidural block and without it during kidney transplantation in Pediatric patients. METHODS: 61 Pediatric patients undergoing kidney transplantation were divided into two groups. General anaesthesia with sevoflurane, propofol, phentanilum and regional ropivacaine epidural block were used in the group 1. General anaesthesia was used only in the group 2. Haemodynamic parameters were assessed: Arterial blood pressure, stroke volume, central venous pressure and cardiac index. RESULTS: Both techniques of anaesthesia were adequate. CONCLUSION: regional ropivacaine epidural block and general anaesthesia combination provides more stable haemodynamic parameters than general anaesthesia single use.

[Oxygenation state of brain in children upon reamberin infusion during post-anesthesia recovery].

The effect of reamberin (1.5% solution of succinic acid and ion complex) on the oxygenation status of the brain was studied in children aged 1 - 14 years during recovery from anesthesia. It is established that reamberin in a dose of 2 ml/kg administered twice at the end of an operation increases the fraction of oxidized hemoglobin and cytochrome oxidase and enhances the regional saturation of brain tissue with oxygen, which is indicative of an increase in the potential of metabolism activation in neurons.

[Reamberin administration for early postnarcosis recovery in children].

The possibility of using 1.5% succinic acid solution (reamberin) in order to activate recovery from anesthesia was studied in a group of 91 patients aged 1-14 years. Based on clinical data and BIS-index, it is established that the administration of reamberin during exit from anesthesia stage shortens the wake-up period, decreases the time of restoration of the motor activity and adequate respiration, and accelerates brain function recovery.

[Postoperative infusion therapy in children].

The study investigates the influence of Voluven 6% and HAES-steril 10% on the hemodynamics and organism water balance of 40 children from 3 months to 17 years of age, which were divided into two groups according to the type of the administered colloid. It is acquired that infusion of colloids with 1:3 ratio compared to crystalloids in general volume of infused liquids (Voluven 6% in the dose of 5 ml/kg/hour in case of median blood loss of 15% of the total circulating blood volume during two hour long surgery and HAES-steril 10% in the dose of 4 ml/kg/hour in case of the blood loss up to 25% of TCBV) allows to effectively neutralize hemodynamic changes based upon administration of anesthetic agents and intraoperative fluid loss. While administration of Voluven 6% is accompanied by significant, statistically accurate decrease of lower limb impedance, which indicates the increased amount of water in them, HAES-steril 10% administration leads to redistribution of water in the body segments with its predominant significant increase in the torso.

[Pharmacokinetics of fentanyl during sevoflurane based general anesthesia in children].

The research is based on the analysis of 50 cases of anesthesia during reconstructive surgeries in children. The anesthesia was based on inhalation of sevolflurane and injection of fentanyl by the bolus infusion scheme. During the different stages of anesthesia the opioid concentration in plasma was measured. Analysis of hemodynamic parameters showed no statistically significant differences in changes in performance, indicating the steady flow of anesthesia. Infusion of fentanyl provided a smooth, gradual decrease in its concentration in plasma, while analgesia remained adequate. The combination of sevoflurane in a concentration of 1.3 MAC and infusion of fentanyl to a total dose 6 mkg/kg/h was effective in provisioning stable anesthesia in the given category of patients with surgical pathology.

[Postanesthetic agitation syndrome after inhalation anesthesia with sevofluorane in children].

The paper analyzes the publications dedicated to the problem of agitation after inhalation anesthesia with sevofluorane. A brief explanation of the conception "agitation" is given in the context of interpretation of explanatory and psychological dictionaries. According to most of the analyzed papers, it is concluded that the incidence of the postanesthetic agitation syndrome occurs after anesthesia with sevofluorane than after that with halothane. The leading risk factors of agitation are preschool age, significant psychoemotional lability in the preoperative period (difficult parting with parents), fear. The efficiency of the preventive measures given in the analyzed paper is disputable. These include opioids (fentanyl), benzodiazepines (midasolam), clonidine, ketamine, dexmedotomidine, nitrous oxide, propofol, etc. The authors conclude that this problem is of no high significance in the aspect of priority, the width and safety of sevofluorane use in the anesthetic maintenance of children although it by far needs further more detailed study.

Interhemispheric asymmetry in EEG photic driving coherence in childhood autism.

OBJECTIVE: Examination of the EEG photic driving coherence during intermittent photic stimulation in autistic patients with relatively intact verbal and intellectual functions in order to enhance the likely latent interhemispheric asymmetry in neural connectivity. METHODS: Fourteen autistic boys, aged 6-14years, free of drug treatment, with I.Q. 91.4+/-22.8, and 19 normally developing boys were subject to stimulation of 12 fixed frequencies of 3-27Hz. The number of high coherent connections (HCC) (coherence >0.6-0.8) was estimated among 7 leads in each hemisphere. RESULTS: In contrast to the spectral characteristics showing the right hemisphere deficit in the photic driving reactivity, the number of HCC differentiated the groups only in the left hemisphere where it was higher in autistics at the EEG frequencies corresponding to those of stimulation at 6-27Hz without asymmetry at other frequencies, the left-side prevalence increasing with frequency. No asymmetry was observed in the resting state. CONCLUSIONS: Spectral and coherence characteristics of the EEG photic driving show different aspects of latent abnormal interhemispheric asymmetry in autistics: the right hemisphere "hyporeactivity" and potential "hyperconectivity" of likely compensatory nature in the left hemisphere. SIGNIFICANCE: The EEG photic driving can reveal functional topographic alterations not present in the spontaneous EEG.

[EEG bispectral index as an indicator of the electrical activity of the central nervous system in children during anesthetic maintenance and intensive care].

The paper presents different investigators' data on the use of the bispectral (BIS) index in children during anesthetic maintenance and intensive care. The most of publications deal with the use of the BIS index during anesthesia with sevoflurane, which shows its high efficiency in estimating the depth of sleep. There are positive aspects in the use of the BIS index in the evaluation of sedative tolerance and central nervous system function, when brain death is diagnosed, cerebral oxygenation adequateness, etc. Data are given on the ambiguity of BIS index values in infants less than a year of age.

Liquid crystal as laser medium with tunable gain spectra.

Amplified spontaneous emission intensity and gain spectra in polarized light have been measured in a dye doped nematic liquid crystal for different orientation of its optical axis and pump intensity. A possibility for switching the gain of the liquid crystal by an external electric field is shown experimentally. The liquid crystal materials with field controlled gain can be used in microlasers and light micro-amplifiers in both planar and waveguiding geometry.

[Effect of volatile inhalational anesthetics on cerebral blood volume and oxygen status in children].

The investigation evaluated the effect of various volatile anesthetics on cerebral blood volume and oxygen status in sick children at the stage of anesthesia induction. Ninety-two children were distributed into 3 groups: Groups 1 (n = 36) and 2 (n = 24) underwent stepwise induction with halothane and enflurane, respectively. Group 3 (n = 32) had vital capacity rapid inhalation induction with sevoflurane. Cerebral oximetry (NIRS method) was used to measure the content of hydroxyhemoglobin, deoxyhemoglobin, the total level of hemoglobin and to assess regional cerebral tissue saturation (rSO2). Halothane was ascertained to increase cerebral blood volume by 20.5% whereas enflurane and sevoflurane increased it only by 8.8 and 9.0%, respectively. In all cases, the value of rSO2 remained comparatively high, by exceeding the baseline level by 3-5%.

[Central and cerebral hemodynamics during gynecological laparoscopic interventions in children].

The authors examined central and cerebral hemodynamics in children during gynecological laparoscopic interventions. The course of 64 anesthesias was analyzed in girls aged 3 to 16 years, who had undergone laparoscopic surgery. Central hemodynamics was studied by tetrapolar rheography on a Diamant apparatus; cerebral oximetry was examined on a Critikon RedOx Monitor 2020 device. The findings demonstrate that pneumoperitoneum application causes immediate cardiovascular changes. Transfer of patients to Trendelenburg's position had a beneficial impact on central hemodynamics, by facilitating the normalization of venous return, thus maintaining cardiac output. Central hemodynamic disorders promptly affected cerebral blood volume and oxygen status. After pneumoperitoneum application, there was an average of 3% reduction in regional cerebral tissue saturation.

[Temperature balance and the possibility of its maintenance during general anesthesia in children].

The problems of hypothermia in the perioperative period, which are one of the most important ones in pediatric practice, in babies in particular, are solved, by using a broad spectrum of methods for preventing and correcting the patients' thermal balance. Convection heating systems exercise an on-line control over the baby's thermal regime during a surgical intervention and intensive care. The authors' own experience allows these systems to be recommended for wide practical application in the activities of anesthesiology and intensive care services.

Topographic aspects of photic driving in the electroencephalogram of children and adolescents.

The electroencephalogram amplitude spectra at 11 fixed frequencies of intermittent photic stimulation of 3 to 24 Hz were combined into driving "profiles" for 14 scalp points in 8 male and 7 female normal subjects aged 9 to 17 years. The driving response varied over frequency and was detected in 70 to 100% of cases in the occipital areas (maximum) and in 27 to 77% of cases in the frontal areas (minimum) using as a criterion peak amplitude 20% higher than those of the neighbors. Each subject responded, on average, to 9.7 +/- 1.15 intermittent photic stimulation frequencies in the right occipital area and to 6.8 +/- 1.97 frequencies in the right frontal area. Most of the driving responses (in relation to the previous background) were significant according to the spectral F-test (alpha = 0.05), which also detected changes in some cases of low amplitude responses not revealed by the peak criterion. The profiles had two maxima in the alpha and theta bands in all leads. The latter was not present in the background spectra in the posterior areas and was less pronounced in the anterior ones. The weight of the profile theta maximum increased towards the frontal areas where the two maxima were similar, while the profile amplitudes decreased. The profiles repeated the shape of the background spectra, except for the theta band. The interhemispheric correlation between profiles was high. The theta driving detected in all areas recorded suggests a generalized influence of the theta generators in prepubertal and pubertal subjects.

[Water balance and pharmacokinetics of ketamine during anesthesia in roentgen-endovascular procedures in children]. / Vodnyi balans i farmakokinetika ketamina pri anesteziologicheskom obespechenii rentgenoéndovaskuliarnykh vmeshatel'stv u detei.

Forty-seven children, aged 2 to 12, with different pathologies, who underwent the abdominal aortography with the bolus introduction of 60% verografin, i.e. a radiopaque contrast agent (RCA), 2-3 ml/kg for 2-3 sec. The osmolar index of blood went up sharply, diuresis increased 7-fold and the aldosterone content topped 2-fold the original level. Simultaneously, the plasma concentration of ketamine was reducing by 2 times faster than in children who were not administered RCA. An additional introduction of an anesthetic made on minute 3 after RCA injection was suggested to modify the anesthesia management scheme.

[Nutritional therapy in children during perioperative period]. / Nutritivnaia terapiia u detei v perioperatsionnom periode.

The efficiency of nutritive therapy was analyzed in cases of 37 patients with gastrointestinal pathologies. Group 1 comprised 12 patients with fistulas of different etiologies and localizations; and group 2 comprised 15 patients with esophageal pathologies, including 7 children with esophageal atresia and 8 children with post-burn cicatricial stenosis of the esophagus. A method of nutrition-status correction by means of both enteral and parenteral feeding is suggested on the basis of examination findings comprising both clinical and laboratory-and-instrumental data. Preparations for parenteral feeding, i.e. 10-20% fatty emulsions, 10% amino acids solutions and 15-20% glucose solutions, were made use of. Enteral diets: semi-element oligopeptide solutions, like Nutrilon pepti TSC, Alphare. Balanced mixtures: sour-milk Nan, AL 110, Nutrizon, Nutridrink. Practical recommendations were defined, on the basis of study results, as to the therapeutic feeding schemes during the in-hospital treatment stages.