POSTOPERATIVE PULMONARY COMPLICATIONS AND ACUTE RESPIRATORY DISTRESS SYNDROME -BETTER PREVENT THEN TREAT.

In parallel with increasing number, duration and extensiveness of surgical interventions, postoperative pulmonary complications (PPC) and acute respiratory distress syndrome (ARDS) remain the major challenges for anesthesiologists and surgical ICU physicians. PPC and ARDS have multiple risk factors that should be recognized early and modifed within the appropriate "time window ". Today we possess reliable models (ARISCAT LIPS, EALI etc.) to predict the risk of non-infectious (hypoxemia, atelectases, pleuritis) and infectious PPC (postoperative pneumonia). The bundle of primaty and secondary prevention strategies is available and can be implemented both in the perioperative settings and in the ICU in patients at risk of PPC and ARDS. The prophylactic approach is realized as a bundle of strategies presented in "Checklist for Lung Injury Prevention" (CLIP). The bundle of preventive protective ventilation comprises low tidal volume (6-8 ml/kg predicted body weight), control of respiratory plateau and driving pressures, moderate positive end- expiratory pressure (PEEPS cm H20), and minimal safe level of inspired oxygen fraction. Pharmacological prevention ofARDS has shown quite satisfactory experimental results and needs further clinicql investigations.

[MONITORING OF CEREBRAL OXYGENATION AND COGNITIVE FUNCTION IN CAROTID ENDARTERECTOMY: THE ROLE OF TRANSIENT BYPASS OF CAROTID ARTERY].

UNLABELLED: BACKGROUND AND OBJECTVE: Carotid endarterectomy (CEE) is an effective surgical technique to prevent cerebral ischemia and stroke, but can be associated with intervention-related complications. The surgical shunting of the intervention area may reduce the risk of the intraoperative ipsilateral cerebral ischemia following the carotid artery clamping but is controversial. The goal of this study was to compare the cerebral tissue oxygen saturation (SctO2) and early changes of cognitive functions in CEE in the settings of transient vascular bypass and without this method. METHODS: 45 adult patients were randomized to either the bypass group (the Bypass group, n = 24) or the Controls / No Bypass (the Control group, n = 21). All patients were monitored for invasive arterial pressure, SpO, EtCO,, and cerebral oxygenation (SctO2, Fore-Sight, CASMED, USA) over the contra- and ipsilateral frontal head areas. The cognitive functions were assessed using series of Montreal Cognitive Assessment score (MoCA) before the intervention, and on 6 and 36 hrs after the CEE. RESULTS: We did not find intergroup differences in the surgery duration, degree of stenosis and baseline cognitive function. The values of SctO2 reduced significantly only above contralateral side; these changes were attenuated in the shunt group. There were no intergroup differences in postoperative cognitive function. CONCLUSION: Empiric transient vascular bypass during carotid endarterectomy did not result in significant changes of the ipsilateral cerebral oxygenation, hyperperfusion and cognitive function, but attenuated the decrease of SctO2 over the contralateral hemisphere.

[The age-related characteristics of changes in osmotic and ionic homeostasis in spontaneously hypertensive rats]. / Vozrastnye osobennosti izmenenii osmoticheskogo i ionnogo gomeostaza u spontanno-gipertenzivnykh krys.

The 3-month old SHR differ from the WKY rats in that the former have an increased osmolality, concentration of albumins, activity (but not the concentration) of sodium and a reduced activity of potassium. The shifts in the albumins concentration occur, mainly, on account of the amino acid phenylalanine. The gradient increase of the sodium and potassium concentration between the plasma and muscular tissue in followed by a slight hyperpolarisation of the muscle fibers, a drop in the lability and a increase in pO2. The above shifts of homeostatic parameters were not revealed in the SHR and WKY rats of 1.5 and 6.0 months of age.

[Potassium distribution in rat tissues in relation to its concentration in the blood]. / Raspredelenie kaliia v tkaniakh krys v zavisimosti ot ego kontsentratsii v krovi.

The dynamics of distribution of potassium and sodium among the blood plasma and the tissues (muscle and liver) was studied in Wistar rats at an artificial increase of the potassium content in the blood. After administration of 1.25% solution of potassium chloride into the stomach (5 ml/100 g), into the liver portal vein (0.5 ml/100 g), and into femoral vein (0.1 ml/min during 45 min), the changes of potassium and sodium contents were opposite in the blood plasma and in the tissues under study. The maximal shift of these ions concentration in the plasma and tissues occurs sooner after administration of potassium directly into the blood. In continuous administration of the solution the potassium concentration reaches 10.8 mM/l in the blood plasma and returns to normal values within 2 hrs after cessation of the administration. Therefore, the redistribution of potassium between extra- and intracellular fluid plays a major role in restoration of the potassium homeostasis.

[Effect of the ion composition and osmotic properties of blood plasma on the erythrocytes of normotensive and hypertensive rats]. / Vliianie ionnogo sostava i osmoticheskikh svoistv plazmy krovi na éritrotsity normo- i gipertenzivnykh krys.

Size of the erythrocytes was shown to change depending on the osmolality of "own" plasma in normotensive rats (WKY). Size of the erythrocytes was unaltered in hypoosmotic (the H2O load) and enhanced in hyperosmotic (the NaCl load) and isoosmotic (the KCl load) media in hypertensive rats (SHR). These specific properties of the erythrocytes are supposed to be due to differences in the transport mechanisms of ion transition through membranes.

[Role of tissue depots and the kaliuretic effect of aldosterone in potassium homeostasis]. / Rol' tkanevykh depo i kaliiureticheskogo deistviia al'dosterona v gomeostaze kaliia.

The concentration of potassium in the blood serum and in the skeletal muscle increased in consequence of daily administration of 1.25% KCl solution during 4 days in rats and frogs. The concentration of potassium in frog m. soleus increased by over 50%. DOCA administration together with KCl solution increased the excretion of potassium by kidney. Olivomycin and puromycin inhibited the sodium reabsorption and did not effect the potassium secretion by rat kidney.

[Extrarenal factors regulating the concentration of osmotically active substances and sodium in blood]. / Vnepochechnye faktory reguliatsii kontsentratsii osmoticheski aktivnykh veshchestv i natriia v syvorotke krovi.

After feeding without water the concentration of osmotically active substances changed by 10--12 mosm/l in the blood serum of rabbits and rats. Bilateral section of the renal crus led to osmotic changes in serum after administration of water or sodium solution during first 15 min which disappeared within 45 min. Large concentrations of sodium solution induced considerable changes in these animals which still were lesser than could have been expected. The data obtained emphasize significance of extrarenal factors for regulation of shifts occurring in disturbances of osmotic and ion balance.

[Ion excretion by the rat kidney in depressed reabsorption in proximal tubule and ascending protion of the loop of Henle]. / Vydelenie ionov pochkoi krysy pri ugnetenii reabsorbtsii v proksimal'nom kanal'tse i voskhodiashchem otdele petli Genle.

Simultaneous suppression of reabsorption in the proximal tubule with the aid of polyethylenglucole 400 (PEG) and in ascending part of Henle's loop with furosemide increased diuresis by 121 times and natri-uresis by 242 times on the average. The increase was based on changes in the tubule reabsorption and secretion. The changes of sodium and calcium excretion as well as excretion of potassium and magnesium were parallel. Excretion of sodium and calcium was lesser than the diuresis while that of magnesium and potassium exceeded it. Furosemide reduced the reabsorption of osmotically free water.

[Reparative processes in the liver and adrenal cortex of rats following an experimental vascular crisis]. / Reparativnye protsessy v pecheni i kore nadpochechnikov krys posle éksperimental'nogo sosudistogo kriza.

Reparative processes in the liver and the adrenal cortex of hemiadrenalectomized female rats, which sustained an acute circulatory disturbance as a result of orthostasis, were investigated by means of quantitative methods (cytometry, kariometry, nucleolometry, determination of cell content calculation of nucleo-cytoplasmic, nucleolo-nuclear ratios). Common features in regeneration of the organs under study were found. During the first days of the experiments the count of the dying cells increased and simultaneously the quantity of amitoses and binucleated cells in the liver grew. The cell composition of the organs was stabilized by the 15th day in the adrenal gland and by the 45th day in the liver. During the first week after orthostasis mitotic activity of epithelial cells rose in both the organs. Later the regeneration took place at the intracellular level (activation of the nuclear apparatus and hypertrophy of the cell cytoplasm).