Biocompatibility of biphasic α,ß-tricalcium phosphate ceramics in vitro.

The biocompatibility of biphasic α,ß-tricalcium phosphate ceramics, obtained by annealing a compact preform based on ß-tricalcium phosphate powder, was studied in vitro. It was found that within 10-30 days the adhesion of primary dental pulp stem cells located on the surface of biphasic α,ß-tricalcium phosphate ceramics is suppressed. Decrease of the cell number on the surface of biphasic α,ß-tricalcium phosphate ceramics, most likely, can be associated with both the pH level (acidic) as a result of hydrolysis of the more soluble phase of α-tricalcium phosphate and with the nature of surface that changes as a result of the formation and growth of hydroxyapatite crystals.

[Analysis of respiratory complications during artificial ventilation of the lungs in patients with organophosphorus compound poisoning]. / Analiz respiratornykh oslozhnenii pri provedenii IVL u bol'nykh s otravleniiami fosfororganicheskimi soedineniiami.

The authors analyze the respiratory complications in patients with acute respiratory failure (ARF) developing as a result of poisoning with organophosphorous (OPC). Twenty-two percent of 470 patients had to be maintained on forced ventilation because of ARF. The indications for forced ventilation of the lungs are as follows: paralysis of respiratory muscles, 90% drop of vital capacity of the lungs, and disorders of the gaseous composition of the blood (PaCO2 over 56 +/- 3 mm Hg and PaO2 below 67 +/- 5 mm Hg). The incidence of respiratory complications among patients on forced ventilation was as high as 92%, which is due to the pathogenesis of the chemical disease developing after OPC poisoning. The complications are the most incident among men aged 30 to 60. The respiratory distress syndrome of adults ranks first among the respiratory complications. It was diagnosed in 70.6% of dead subjects in 34.4% of convalescents. This syndrome is one main cause of high mortality, particularly so in subjects dying in three or more days of intensive care. The duration of forced ventilation of the lungs does not depend on the time when the patient was transferred on ventilation or on the poison. Analysis of mortality indicates that it is lower among patients administered forced ventilation at the prehospital stage.

[Optimization of artificial pulmonary ventilation in patients with organophosphorus compound poisoning complicated by development of exotoxic shock]. / Optimizatsiia provedeniia IVL u bol'nykh s otravleniiami fosfororganicheskimi soedineniiami, oslozhnennymi razvitiem ékzotoksicheskogo shoka.

Central hemodynamics, phase structure of left-ventricular systole, and paO2 were studied in 104 patients with organophosphorus poisoning complicated by exotoxic shock during forced ventilation of the lungs (FVL) with positive zero expiration pressure, positive end expiration pressure +5, +7, +10 cm H2O, and high-frequency FVL. FVL with positive end expiration pressure +5 or +10 cm H2O was found to be the optimal for patients with compensated shock. In patients with decompensated phase of exotoxic shock FVL with positive zero expiration pressure and FVL with positive end expiration pressure +5 cm H2O, although having no negative impact on the hemo- and cardiodynamics, did not provide sufficient oxygenation of the blood. Higher values of positive end expiration pressure (+7, +10 cm H2O) brought about disorders of heart work. High-frequency FVL appears to be the most rational in patients with decompensated phase of shock.