Блокада грудных нервов как компонент мультимодальной анальгезии при операциях по поводу рака молочной железы

Objective: to evaluate the efficacy and safety of adding pectoral nerve block to anesthesia regimen in radical mastectomy.Subjects and methods. 65 female patients underwent unilateral radical mastectomy under general anesthesia. All patients enrolled into the study were divided into two groups. Group 1 included patients (the main one, n = 33) who had PEC block and general anesthesia; Group 2 (the control one, n = 32) had general anesthesia only.Results. The group of patients with PEC block versus the Control Group, demonstrated a lower score of the visual analogue scale at all stages of the study. The intra-operative fentanyl consumption was statistically significantly lower in Group 1 versus the Control Group (290.91 ± 67.84 and 393.75 ± 66.90 μg, respectively, p < 0.033). The consumption of opioid analgesics during the 1st day in the Main Group was 2-fold lower compared to the Control Group – 30.91 ± 12.34 and 63.75 ± 9.42 mg, respectively (p < 0.026). In Group 1, the time till the first analgesia with promedol made 309.55 ± 56.59 minutes.Conclusions. Pectoral nerves block combined with general anesthesia provides effective analgesia during breast surgery with axillary lymph node dissection.Цель исследования: оценить эффективность и безопасность включения блокады грудных нервов в схему обезболивания при радикальной мастэктомии.Материал и методы: 65 пациенткам выполнена односторонняя радикальная мастэктомия под общей анестезией. Все пациентки, включенные в исследование, разделены на две группы. В 1-ю группу включены пациентки (основная, n = 33), которым проведены PEC block и общая анестезия; во 2-й группе (контрольная, n = 32) проведена только общая анестезия.Результаты. В группе пациентов с PEC block в сравнении с контрольной группой выявлен более низкий показатель по визуально-аналоговой шкале на всех этапах исследования. Интраоперационная потребность в фентаниле статистически значимо была меньше в 1-й группе по сравнению с контрольной (290,91 ± 67,84 и 393,75 ± 66,90 мкг соответственно, p < 0,033). Потребность в опиоидных анальгетиках в 1-е сут в основной группе была в 2 раза меньше, чем в контрольной ‒ 30,91±12,34 и 63,75 ± 9,42 мг соответственно (p < 0,026). Время до первого обезболивания промедолом в 1-й группе составило 309,55 ± 56,59 мин.Выводы. Блокада грудных нервов в комбинации с общей анестезией обеспечивает эффективную анальгезию при операции на молочной железе с подмышечной лимфодиссекцией

Transport Properties of Silicon δ-Doped Gaas in High Electron Density Regime

We report results for Si layers embedded in GaAs, extending from the delta-doped (δ-doped) range up to 6 monolayers derived by means of variable temperature resistivity and Hall effect measurements, secondary ion mass spectrometry and high resolution X-ray diffractometry techniques. The conductivity transition from free carrier transport in ordered δ-layers (4 ML) is clearly observed. This observation is in good agreement with the secondary ion mass spectrometry and high resolution X-ray diffractometry data. Results from the intermediate case with 2-3 MLs are also discussed

Pectoral nerves block as a component of multimodal analgesia in breast cancer surgery

Objective: to evaluate the efficacy and safety of adding pectoral nerve block to anesthesia regimen in radical mastectomy.Subjects and methods. 65 female patients underwent unilateral radical mastectomy under general anesthesia. All patients enrolled into the study were divided into two groups. Group 1 included patients (the main one, n = 33) who had PEC block and general anesthesia; Group 2 (the control one, n = 32) had general anesthesia only.Results. The group of patients with PEC block versus the Control Group, demonstrated a lower score of the visual analogue scale at all stages of the study. The intra-operative fentanyl consumption was statistically significantly lower in Group 1 versus the Control Group (290.91 ± 67.84 and 393.75 ± 66.90 μg, respectively, p < 0.033). The consumption of opioid analgesics during the 1st day in the Main Group was 2-fold lower compared to the Control Group – 30.91 ± 12.34 and 63.75 ± 9.42 mg, respectively (p < 0.026). In Group 1, the time till the first analgesia with promedol made 309.55 ± 56.59 minutes.Conclusions. Pectoral nerves block combined with general anesthesia provides effective analgesia during breast surgery with axillary lymph node dissection

Fermi-Edge Singularity in Excitonic Spectra of Modulation Doped AlGaAs/GaAs Quantum Wells

The dynamic response of an electron Fermi sea to the presence of optically generated holes gives rise to an enhanced interaction of correlated electron-hole pairs near the Fermi level, resulting in an enhanced oscillator strength for optical transitions, referred to as the Fermi-edge singularity. We studied this effect in modulation-doped quantum wells which provide confined dense Fermi sea, spatially separated from dopant atoms, easily accessible for investigations under low excitation conditions. The Fermi-edge singularity was observed in both photoluminescence and photoluminescence excitation experiments, although in the case of photoluminescence the samples had to be either co-doped with acceptors in the wells to provide necessary localization of holes or designed to allow for nearly resonant scattering between the electronic states near the Fermi energy and the next unoccupied subband of the 2D electron gas