Fabrication and tunable reinforcement of net-shaped aluminum matrix composite parts via 3D printing.

Advanced materials, such as metal matrix composites (MMCs), are important for innovation, national security, and addressing climate change. MMCs are used in military, aerospace, and automotive applications because of their exceptional mechanical and thermal properties, however adoption has been slow due to costly and onerous manufacturing processes. A new process using fused filament fabrication 3D printing has been developed to make net shape MMCs without tooling or machining.

[Subclavian-carotid replacement in chronic cerebrovascular insufficiency management].

Aim: To present own experience of subclavian-carotid replacement for chronic cerebrovascular insufficiency management.

Material And Methods: For 12 years 7 subclavian-carotid reconstructions were performed that was 1.2% of all carotid repairs during this period.

[MODERN TECHNOLOGIES OF THE SAVING OF PATIENT'S BLOOD AND REDUCTION OF THE USE OF DONOR BLOOD DURING OPERATIONS ON THE ASCENDING AORTA AND AORTIC ARCH].

Questions of saving of the patient's blood and limitation of the use of donated blood in the aortic surgery remain relevant in contrast with interventions on the valves of the heart and coronary arteries. In this regard, the aim of the study was to develop and introduce ofcomplex of technologies for saving the patient's blood in order to minimize transfusion of donor blood components during operations on the ascending aorta and aortic arch under hypothermic arrest. The study included 37 patients operated on the ascending aorta and aortic arch under cardiopulmonary bypass (CPB) and hypothermic cardiac arrest (CA) in 2013-2014 (Group 1).

Note: High-speed optical imaging powered by acoustic emission triggering.

Aiming at high speed video recording of rapid events, which occur in loaded solids with unpredictable timing, the efficient triggering method is proposed for optical imaging systems with an aid from the highly sensitive acoustic emission technique. The efficiency of the proposed method is demonstrated on two examples: observation of initiation and propagation of highly localized shear bands in metallic glasses and mechanical twinning in Mg polycrystals.

[Simultaneous coronary bypass grafting and hemicolectomy].

The simultaneous surgical treatment of ischemic heart disease (coronary bypass grafting) and ascending colon cancer (right hemicolectomy) is described. Literature review showed that these simultaneous surgical heart and colon procedures are reasonable and should become a method of choice for such patients.

[Grafting of carotid arteries].

Over 5-years, 167 reconstructive surgeries for stenosis of internal carotid arteries (ICA) were performed in 124 patients. Mean age of the patients was 63.5 years.

[Anesthesia in surgical treatment of the ascending aorta-arch aneurysms].

The paper analyzes anesthesiological maintenance of infusion therapy, optimal criteria for effective brain protection, complications and mortality in 42 patients during operations on the ascending portion and arch of the aorta under deep hypothermic circulatory arrest. For this purpose, the patients were divided into 2 groups: Group 1 comprised 20 patients operated on before 1998; Group 2 included 22 patients operated on in 1998 to 2001. In both groups, circulatory arrest lasted 44 +/- 7 min.

[Anesthesia, changes in hemodynamics and metabolism in surgical treatment of thoracic and abdominal aortic aneurysms].

45 patients aged 32-63 years operated on for dissecting aneurysm of the thoracoabdominal part of the aorta were divided into 2 groups. Group 1 patients (n = 36) were operated on with application of the bypass using centrifuge pump. Group 2 patients (n = 9) were operated on without the bypass.

[Combined spinal-epidural and epidural anesthesia in operations on the vessels of the lower extremities].

Eighty-eight anesthesias in patients operated on the lower limb vessels are analyzed. In group 1 (77 pts) combined spinal-epidural anesthesia (CSEA) was used, in group 2 (16 pts) epidural anesthesia (EA). Segmentary blocking was induced by 2% lidocaine and 0.

[Use of a new Russian antihypertensive drug dilazin in surgery of the coronary arteries and abdominal aorta].

Dilazin in a dose of 0.2 mg/kg/min (n = 20) and 0.4 mg/kg/min (n = 20) was used to normalize arterial blood pressure during and after surgery.

[Use of combined lidocaine and bupivacaine spinal-epidural anesthesia in vascular surgery of lower limbs].

The efficacy of combined spinal epidural anesthesia (CSEA) for femoral to distal artery bypass surgery is assessed. Thirty-eight patients were divided into 3 groups. CSE block was performed at L3-L4 (26G pensil-point spinal needle and 18G catheter).

[Changes in bioelectric activity and metabolism of the brain during surgery of the aorta under deep hypothermic arrest of circulation].

Bioelectric activity and metabolism of the brain were studied during surgery on the aorta with deep hypothermal arrest of circulation. The study included 9 patients (7 men and 2 women) aged 13 to 66 years. The mean duration of circulation arrest under deep hypothermia was 48.

[The use of continuous spinal anesthesia and combined spinal-epidural anesthesia in operations on lower extremity vessels].

Continuous spinal anesthesia with hyperbaric solution of 1% lidocaine and 0.375% bupivacaine and combined spinal-epidural anesthesia with solutions of 2% lidocaine and 0.375% bupivacaine by using in-run anesthesia ensure adequate anesthesia and persistent hemodynamic parameters during operations on lower extremity vessels.

[The monitoring of brain metabolism as the basis for the control of its adequate protection during circulatory arrest under deep hypothermia].

Monitoring of brain metabolism is used to assess the adequacy of brain cooling during operations performed under conditions of deep hypothermal perfusion and temporary arrest of circulation. Such monitoring consists in continuous recording of hemoglobin saturation of the blood flowing from the brain by fiberoptic oximetry and testing of blood samples collected from the upper internal jugular bulb. A patient is described, who had been operated with good results under conditions of deep hypothermal perfusion and 30-min arrest of circulation.

[Anesthesia, changes in hemodynamics and metabolism in resection of abdominal aortic aneurysms].

Changes in hemodynamics and some metabolic parameters were studied in 78 patients during anesthesia for resection of the abdominal aorta aneurysms. The steps of the operation associated with the most profound hemodynamic changes were distinguished and measures aimed at stabilization of hemodynamics, blood volume, and electrolyte balance considered. No appreciable changes in the hemodynamics or depression of the myocardium were observed at stages of anesthesia and operation.

[Effects of nitroglycerin on myocardial contraction in patients with ischemic heart disease].

The effects of nitroglycerin on central hemodynamics and direct myocardial contractility were directly studied in 32 patients with functional class III-IV heart failure during aortocoronary bypass surgery. When nitroglycerin was used, hemodynamic parameters changed in two stages: 1) systemic blood pressure initially slightly increased; 2) decreases in this and other central hemodynamic parameters occurred. The dynamics of myocardial function was determined by its baseline state, dyskinetic intensity, i.

[Effects of halothane on cerebral blood flow and its protective action in ischemia].

Halothane impact on cerebral blood flow, brain metabolism and its protective effect in ischemia have been assessed in 30 patients operated on for the occlusion of brachiocephalic arteries. The data obtained indicate that additional use of halothane in N2O:O2 anesthesia during reconstructive surgery on brachiocephalic arteries makes it possible to enhance collateral blood flow, increase retrograde pressure, and decrease O2 consumption by the brain, without considerable changes in systemic hemodynamics. In addition, the studies have shown that halothane decreases lipid peroxidation processes.

[Balanced anesthesia using the new Russian analgesic fenaridina in cardiovascular surgery and its effect on hemodynamics and respiration].

A new analgesic fenaridine which was used as a component of balanced anesthesia in 160 operations of aortocoronary bypass has been studied. It has been shown that fenaridine is a potent analgesic, exceeding fentanyl in the duration of action and in its analgetic effect. Fenaridine has a pronounced sedative effect and like other analgesics causes a dose-dependent depression of respiration.

[Anesthesia and brain protection in reconstructive surgery of brachiocephalic arteries].

Application of a shunt is not the principal factor preventing brain blood flow disorders in reconstructive surgery on the carotid arteries in conditions of general anesthesia with anesthetics of an antihypoxic action, reducing oxygen consumption by the brain, combined with adequate compensation of the circulating blood volume, moderate hemodilution, elevation of the systemic arterial pressure and heparin. The authors claim that even in patients with bilateral stenosis of the carotid arteries or with occlusion of one of these arteries surgery may be carried out without shunts or craniocerebral hypothermia. Still, they do not deny a bypass application, particularly by the surgeons who always use it, or in cases with a drastic inhibition of the brain electrical activity, evidenced by EEG, which they consider a sufficiently reliable indicator of the brain blood flow adequacy.

[The concentration of potassium in the blood and 2,3-diphosphoglyceric acid in the erythrocytes during surgery of the abdominal aorta accompanied by massive blood loss].

It has been demonstrated that transfusions of large amounts of stabilized donor blood and prolonged ischemia due to clamping of the abdominal aorta during surgery were not accompanied by an increase in K+ plasma level thanks to therapy aimed at the correction of hypovolemia and hemodynamic stabilization. A decrease in K+ plasma level directly depended on the volume of the liquid transfused, the degree of hemodilution and to some extent on 2,3-DPG level. There was a drop in 2,3-DPG level intraoperatively, which was due to the use of stored donor blood for blood loss compensation and to mounting metabolic acidosis (lactate acidosis included) and gaseous acidosis.