[Experts consensus on the management of the right heart function in critically ill patients].

To establish the experts consensus on the right heart function management in critically ill patients. The panel of consensus was composed of 30 experts in critical care medicine who are all members of Critical Hemodynamic Therapy Collaboration Group (CHTC Group). Each statement was assessed based on the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) principle. Then the Delphi method was adopted by 52 experts to reassess all the statements. (1) Right heart function is prone to be affected in critically illness, which will result in a auto-exaggerated vicious cycle. (2) Right heart function management is a key step of the hemodynamic therapy in critically ill patients. (3) Fluid resuscitation means the process of fluid therapy through rapid adjustment of intravascular volume aiming to improve tissue perfusion. Reversed fluid resuscitation means reducing volume. (4) The right ventricle afterload should be taken into consideration when using stroke volume variation (SVV) or pulse pressure variation (PPV) to assess fluid responsiveness.(5)Volume overload alone could lead to septal displacement and damage the diastolic function of the left ventricle. (6) The Starling curve of the right ventricle is not the same as the one applied to the left ventricle,the judgement of the different states for the right ventricle is the key of volume management. (7) The alteration of right heart function has its own characteristics, volume assessment and adjustment is an important part of the treatment of right ventricular dysfunction (8) Right ventricular enlargement is the prerequisite for increased cardiac output during reversed fluid resuscitation; Nonetheless, right heart enlargement does not mandate reversed fluid resuscitation.(9)Increased pulmonary vascular resistance induced by a variety of factors could affect right heart function by obstructing the blood flow. (10) When pulmonary hypertension was detected in clinical scenario, the differentiation of critical care-related pulmonary hypertension should be a priority. (11) Attention should be paid to the change of right heart function before and after implementation of mechanical ventilation and adjustment of ventilator parameter. (12) The pulmonary arterial pressure should be monitored timingly when dealing with critical care-related pulmonary hypertension accompanied with circulatory failure.(13) The elevation of pulmonary aterial pressure should be taken into account in critical patients with acute right heart dysfunction. (14) Prone position ventilation is an important measure to reduce pulmonary vascular resistance when treating acute respiratory distress syndrome patients accompanied with acute cor pulmonale. (15) Attention should be paid to right ventricle-pulmonary artery coupling during the management of right heart function. (16) Right ventricular diastolic function is more prone to be affected in critically ill patients, the application of critical ultrasound is more conducive to quantitative assessment of right ventricular diastolic function. (17) As one of the parameters to assess the filling pressure of right heart, central venous pressure can be used to assess right heart diastolic function. (18). The early and prominent manifestation of non-focal cardiac tamponade is right ventricular diastolic involvement, the elevated right atrial pressure should be noticed. (19) The effect of increased intrathoracic pressure on right heart diastolic function should be valued. (20) Ttricuspid annular plane systolic excursion (TAPSE) is an important parameter that reflects right ventricular systolic function, and it is recommended as a general indicator of critically ill patient. (21) Circulation management with right heart protection as the core strategy is the key point of the treatment of acute respiratory distress syndrome. (22) Right heart function involvement after cardiac surgery is very common and should be highly valued. (23) Right ventricular dysfunction should not be considered as a routine excuse for maintaining higher central venous pressure. (24) When left ventricular dilation, attention should be paid to the effect of left ventricle on right ventricular diastolic function. (25) The impact of left ventricular function should be excluded when the contractility of the right ventricle is decreased. (26) When the right heart load increases acutely, the shunt between the left and right heart should be monitored. (27) Attention should be paid to the increase of central venous pressure caused by right ventricular dysfunction and its influence on microcirculation blood flow. (28) When the vasoactive drugs was used to reduce the pressure of pulmonary circulation, different effects on pulmonary and systemic circulation should be evaluated. (29) Right atrial pressure is an important factor affecting venous return. Attention should be paid to the influence of the pressure composition of the right atrium on the venous return. (30) Attention should be paid to the role of the right ventricle in the acute pulmonary edema. (31) Monitoring the difference between the mean systemic filling pressure and the right atrial pressure is helpful to determine whether the infusion increases the venous return. (32) Venous return resistance is often considered to be a insignificant factor that affects venous return, but attention should be paid to the effect of the specific pathophysiological status, such as intrathoracic hypertension, intra-abdominal hypertension and so on. Consensus can promote right heart function management in critically ill patients, optimize hemodynamic therapy, and even affect prognosis.

Prediction of volatile anaesthetic solubility in blood and priming fluids for extracorporeal circulation.

Volatile anaesthetics are often used during cardiopulmonary bypass (CPB). To understand the kinetics of inhaled anaesthetics during CPB, anaesthetists should understand changes in blood solubility caused by fluid use. We set out to predict the solubility of three volatile anaesthetics, desflurane, isoflurane and halothane, during CPB by determining: (i) their solubility in fresh whole blood and eight CPB priming fluids at 37 degrees C; (ii) the effect of temperature on the solubility of these anaesthetics in lactated Ringer's, gelofusin, banked blood and plasma; (iii) their solubility in different mixtures of these four priming fluids at different temperatures; and (iv) their estimated and actual solubility in blood during hypothermic CPB. We calculated solubility using a concept of volume fraction partition coefficient and compared estimated and measured solubilities. For the three anaesthetics tested, solubilities are in the order: fresh whole blood approximately = plasma > banked blood > normal saline approximately = lactated Ringer's approximately = gelofusin approximately = Haemaccel approximately = hydroxyethyl starch > mannitol. The solubilities of the anaesthetics in all priming fluids increased logarithmically at lower temperatures (P<0.05). The volume-fraction estimates of the partition coefficients were within approximately +/-20% of the measured values for all values of solubility. The corresponding estimates of solubility for CPB blood samples were between -36% and +24% of the measured values. During normothermic CPB, blood solubility of volatile anaesthetics would be unchanged when using plasma, slightly reduced when using banked blood and markedly reduced when using crystalloids and colloids.

[Optimization of mobile phase composition for RP-HPLC separation and determination of long acting steroidal contraceptives].

The optimization of the reversed phase high performance liquid chromatographic separation of six steroids of long acting contraceptives is described. A procedure is used to determine the design space, calculate the coefficients of a seven-term special cubic equation, and modify the model using the optimum experiment. Assisted with the computer, an optimum area could be predicted by overlapping the minimum resolution map with the analysis time map. It is likely that the method described in this paper will provide the basis or the simultaneous optimization of both separation and analysis time and prove to be a useful tool for the optimization of RP-HPLC of known compounds. We firstly utilized the time programming function to improve the detection sensitivities of estrogenic compounds. This method is successfully applied to the analysis of compound megestrol acetate injection and compound hydroxyprogesterone caproate injection. The method is sufficiently simple and rapid yet sensitive and accurate enough for the quality assurance of these types of pharmaceuticals.

[Quantitative analysis of midecamycin by HPLC].

A reversed phase high performance liquid chromatographic method for the assay of midecamycin was developed. The method used a Hitachi Gel 3050 column at 50 degrees C and a mobile phase of methanol--0.01 mol/L phosphate buffer solution at pH 5.8 (45:55). The column effluent was monitored Z at 231 nm. SF-837A1, leucomycin A6 and minor components could be separated in less than 15 min. The retention times of SF-837A1 and leucomycin A6 are 7 and 10 min respectively. The method is very simple and rapid.

[Use of the Powell method to optimize the composition of HPLC mobile phase--the separation of ephedrine and pseudoephedrine].

The isomers ephedrine and pseudoephedrine are difficult to be separated by HPLC. In this paper, the Powell method was successfully introduced to optimize the composition of mobile phase in HPLC. On a mu Bondapak C18 column (8-10 microns, 3.9 mm x 30 cm), KH2PO4 solution methanol mobile phase system was optimized for separating ephedrine and pseudoephedrine by the Powell method. The optimized composition of the mobile phase was found as: 0.01 mol/L KH2PO4 -MeOH = 94: 6 (V/V). The Powell method was carried out in a process illustrated by tables and figures and 0.95 peak separation function was achieved.

[Determination of ephedrine, pseudoephedrine and strychnine in jiufen san by HPLC].

An HPLC method was established to separate and determine ephedrine (I), pseudoephedrine (II) and strychnine (III) in Chinese traditional medicine, Jiufen San, on a mu-Bondapak C18 column (10 microns, 3.9 mm x 30 cm) by using 0.01 mol/L KH2PO4-methanol as mobile phase. The programmed gradient elution was carried out and recoveries were determined as 98.94 +/- 2.2% for I, 97.37 +/- 1.9% for II and 100.7 +/- 1.9% for III respectively. An extracting and pretreatment method was designed and the result showed that the extracting efficiency of this method was 1.33 times (I) and 1.29 times (II) higher than those of the Chinese Pharmacopoeia method.