Introduction: Successful anesthetic management of microlaryngeal cases requires a high degree of cooperation with the surgeon, a reciprocal understanding of the potential problems, and adequate preparation on both sides to meet the anticipated challenges that may arise. The Aim of the study is to determine the hemodynamic complications during microlaryngeal surgery. Materials and Methods: A 5-year prospective cohort study of 200 patients who underwent microlaryngeal surgery in the

To provide designed oil production and to minimize non-productive time new approaches in hydraulic fracturing have been tried and introduced for several years in Uvat project. During this optimization process, several new technologies were pilot tested including fiber-laden fluid, rod-shaped proppant and channel fracturing technique. The main goal was to improve fracturing fluid reliability and to decrease the risk of premature screen-outs in combination with more aggressive fracturing design to maximize oil production. Uvat project oil field is located in Western Siberia. Jurassic formation is the main oil producer from the field, presented by significant net height (up to 45 m), relatively high permeability which varies in wide range from 2 md to more than 50 mD. The formation temperature is 80-90°C. The requirements to fracture geometry is gradually increase in these conditions. The greater fracture width must be accompanied with sufficient effective fracture half-length. This goal cannot be achieved with standard hydraulic fracturing techniques because of limitations in proppant pack conductivity. Besides, the more aggressive design is associated with the higher risk of premature job screen-out that consequently results in non-productive time. Paper describes the results of pilot projects for the following new technologies introduction: fibers that allow better proppant distribution in the fracture and decrease polymer concentration without sacrificing proppant transportation ability of the fluid (the new generation of fibers was implemented which is for low temperature formation); rod-shaped proppant to prevent particles flowback and to increase fracture conductivity; channel fracturing technology that allows to decrease treatment costs and risk of premature screen-out while keeping or even increasing the flow capacity of the fracture. In channel fracturing application a proppant is added in short pulses alternated with clean fluid pulses. This becomes even more vital in remote locations as the same stimulation result can be achieved with less proppant amount replaced by clean fluid pulses that leads to decrease in spending on logistics and time optimization for fracturing job. The manuscript describes the candidate selection methods for re-fracturing jobs and states the main success criteria (such as presence of formation energy and current skin calculation). The authors represent comparative analysis of horizontal wells and multistage fracturing effectiveness in low productive regions resulted in high incremental oil rate when compared to vertical wells with a single fracture.

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Theoretical basis: Microlaryngeal surgery can be conducted in an awake patient, frequently under conscious sedation, or with the patient anesthetized. The ventilation options under general anesthesia consist of "tube" (i.e., endotracheal intubation) and "tubeless" techniques, with the latter represented by the techniques of Spontaneous ventilation, Apneic intermittent ventilation (AIV), and Jet Ventilation (JV). Results: The use of a small (5.0-mm ID) MLT tube with positive-pressure ventilation remains the standard for airway management in most nonlaser microlaryngeal surgery, and it is associated with minimal or no intraoperative complications. Spontaneous ventilation is rarely used in adult microlaryngeal surgery, but it is commonly employed in the pediatric patient population. AIV remains a relatively popular technique for microlaryngeal surgical procedures of short duration in some surgical centers. Superimposed High-Frequency Jet Ventilation (SHFJV), which combines highfrequency and low-frequency ventilation modes, has been used effectively in surgical treatment of high-grade laryngeal and tracheal stenosis. Conclusion: General anesthesia for microlaryngeal surgery represents a unique example of close cooperation between the surgeon and the anesthesiologist.

Introduction: Pseudocholinesterase deficiency is a genetic or acquired alteration in the metabolism of choline esters such as succinylcholine. Case description: A 70 years old female patient (body weight 48 kg, height 157 cm) was admitted to the hospital for microlaryngeal surgery. The preoperative interrogation revealed no significant personal or family history of adverse reaction to anesthetics. ASA classification is III. We performed a general anesthesia with intubation to the patient. Fentanyl 0.25 mg, propofol 150 mg and succinylcholine 70 mg were administered for anesthesia induction. After intubation 2% sevoflurane was used for anesthesia maintenance. The patient was unresponsive to external stimuli for 40 min since the end of the operation. Tree hours after operation, the patient had totally recovered from paralysis and tracheal tube was removed. Four days after operation the patient was discharged from hospital with no special discomfort. Discussion: Reduced plasma cholinesterase activity may occur as a result of inherited, acquired defects or iatrogenic causes. If the acquired defects are excluded low butyrylcholinesterase enzyme (BChE) activity is usually considered to be caused by mutations in butyrylcholinesterase gene (BCHE). There is no specific treatment for butyrylcholinesterase deficiency and the mainstream is to maintain ventilatory support until succinylcholine is metabolized out of the myoneural junction and neuromuscular function recovers. Transfusion of fresh frozen plasma is also viable. Conclusion:There is no specific treatment for plasma cholinesterase deficiency. The best and safest way is to let the patient recover spontaneously. Mechanical ventilation support is very important.