Objective To investigate whether pulse pressure variation( ΔPP) reflect the effects of PEEP and fluid resuscitation ( FR) on hemodynamic effects. Methods Twenty critical patients with acute lung injury was ventilated with volume control ( VT =8 mL/kg, Ti/Te = 1∶2) , and PaCO2 was kept at 35 to 45 mm Hg. PEEP was setted as 5 cm H2O and 15 cmH2O in randomized order. Hemodynamic parameters including cardiac index, pulse pressure, central venous pressure, etc. were monitered by PiCCO system.Measurements were performed after the application of 5 cmH2O PEEP ( PEEP5 group) and 15 cm H2OPEEP ( PEEP15 group) respectively. When the PEEP-induced decrease in cardiac index ( CI) was gt; 10% ,measurements were also performed after fluid resuscitation. Results Compared with PEEP5 group, CI was decreased significantly in PEEP15 group( P lt;0. 05) , and ΔPP was increased significantly( P lt; 0. 05) . In 14 patients whose PEEP-induced decrease in CI was gt; 10% , fluid resuscitation increased CI from ( 3. 01 ±0. 57) L·min - 1·m- 2 to ( 3. 62 ±0. 68) L·min- 1 ·m- 2 ( P lt;0. 01) , and decreased ΔPP from ( 17 ±3) % to ( 10 ±2) % ( P lt;0. 01) . PEEP15 -induced decrease in CI was correlated negatively with ΔPP on PEEP5 ( r= - 0.91, P lt;0. 01) and with the PEEP15 -induced increase in ΔPP ( r = - 0. 79, P lt;0. 01) . FR-induced changes in CI correlated with ΔPP before FR ( r =0. 96, P lt; 0. 01) and with the FR-induced decrease in ΔPP ( r= - 0. 95, P lt; 0. 01) . Conclusions In ventilated patients with ALI, ΔPP may be a simple anduseful parameter in predicting and assessing the hemodynamic effects of PEEP and FR.
【Abstract】 Objective To isolate and culture human amniotic fluid-derived mesenchymal stem cells (HAFMSCs),to investigate a better cryopreservation protocol of HAFMSCs and to observe the biocharacteristics and the multi-potential of HAFMSCs after cryopreservation for the further fundamental researches and cl inical appl ications. Methods HAFMSCswere isolated from the amniotic fluid of pregnant women during the second trimester by the improved two-step method.HAFMSCs were cryopreserved with different cryopreservation protocols (containing different contents of FBS and DMSO atcryoprotectant) in l iquid nitrogen for 12 weeks. The biocharacteristics of the HAFMSCs after cryopreservation were analyzed. The growth characteristics were observed by MTT method and the growth curves were drawn. The surface antigens of HAFMSCs were detected using flow cytometry, including CD29, CD34, CD44, CD45, CD73, and CD90. The adi pogenic and osteogenic differentiation abil ities of HAFMSCs were observed. The mRNA levels of Oct-4 and Nanog of the HAFMSCs were compared between before and after cryopreservations. Results At 12 weeks after cryopreservation, different protocols had different effects on the cell viabil ity; the better formula of cryoprotectant was 50% DMEM, 40% FBS, and 10% DMSO. After cryopreservation, the cells proliferated rapidly and the growth curves showed “S” shape, which was the same as the cells before cryopreservation. Phenotype showed that HAFMSCs were positive for the surface markers CD29, CD44, CD73, and CD90, and negative for CD34 and CD45. After 21 days of adi pogenic differentiation, the l ipid droplets were observed by oil red O staining. After 21 days of osteogenic differentiation, the calcium mineralizations were verified by von Kossa staining. There was no significant difference (P gt; 0.05) in the mRNA levels of Oct-4 and Nanog between before and after cryopreservations. Conclusion HAFMSCs have rapid proliferation and multi-potential in vitro. The cells have high viabil ities and no changes of the biocharacteristics and differentiation potential ities after cryopreservation for 12 weeks. Cryoprotectant containing 50% DMEM, 40% FBS, and 10% DMSO is a better cryopreservation protocol.
Objective To evaluate the effects and the clinical significances of liquid resuscitation on blood gas analysis， acid-base balance， electrolytes， acute physiology and chronic health evaluationsⅡ（APACHEⅡ） score of patients with septic shock， and then to analyze the relations between serum chlorine （Cl－） level and APACHEⅡscore and the volume of liquid resuscitation. Methods According to the target of resuscitation （centre venous pressure 8-12mm Hg and mean arterial pressure≥65mm Hg）， 21 patients with septic shock received enough fluid for resuscitation during 24h . The results of blood gas analysis， acid-base balance， electrolytes， and APACHE Ⅱ score were compared between pre-resuscitation and 24h post-resuscitation by self-controlled prospective study. The relationships of the level of serum Cl－ and APACHEⅡ score with the volume of liquid used in resuscitation were analyzed . Results The mean resus-citation duration was （18.09±4.57） h， and the volume of liquid during 24 h resuscitation was 5 320-11 028mL with mean volume of （7 775±1 735） mL in 21 patients with septic shock. Serum sodium （Na＋， mmol/L） and Cl－（mmol/L）levels of post-resuscitation were significant higher than those of pre-resuscitation （Na＋：138.71±5.67 versus 135.62±7.23， P=0.024；Cl－：109.10±4.90 versus 101.67±8.59， P=0.000）. Compared with the levels of pre-resuscitation， the blood pH value， hematocrit （Hct，%）， anion gap （AG， mmol/L）， lactic acid （mmol/L）， and APACHE Ⅱscore significantly decreased （pH：7.31±0.05 versus 7.37±0.06， P=0.000；Hct：28.48±2.56 versus 32.76±9.19， P=0.049；AG：8.33±3.45 versus 14.17±8.83， P=0.004；lactic acid：1.66±0.89 versus 2.96±1.23， P=0.001；APACHEⅡ：10.90±3.73 versus 17.24±4.06， P=0.000） after 24h resuscitation. The correlation analysis showed that the level of serum Cl- was positively correlated with the volume of liquid used in resuscitation （r=0.717，P＜0.01）. However， there was no correlation between APACHEⅡscore and the volume of liquid used in resuscitation （P＞0.05）. Conclusions The target of liquid resuscitation in patients with septic shock should be cautiously determined， including control of the volume of crystal liquid for resuscitation， in order to avoid acid-base imbalance or hyperchloraemia. At the same time， the change in internal environment should be monitored. An optimistic fluid resuscitation to decrease APACHE Ⅱ score in patients with septic shock is unrelated to the volume of liquid resuscitation.
Objective To evaluate the effectiveness of fluid therapy on an early goal-directed approach to resuscitation basis and the standard fluid therapy of adequate resuscitation on the prognosis of severe acute pancreatitis （SAP）in early stage. Methods The clinical data of SAP patients admitted to surgical intensive care unit within 72 h after onset of symptoms from January 2000 to November 2011 were analyzed retrospectively. A total of 97 patients with a confirmed diagnosis of SAP were divided into two groups based on whether adopting the early goal-directed fluid resuscitation strategies or not. Patients admitted from January 2000 to December 2004 did not adopt the early goal-directed fluid resuscitation strategies，therefore，being allocated into standard fluid therapy group （n=34）； patients admitted from January 2005 to November 2011 adopted the early goal-directed fluid resuscitation strategies and who were allocated into early goal-directed fluid therapy group （n=63）. With the exception of the fluid therapy strategies，the two group patients received standard treatment for SAP. The acute physiology and chronic health evaluation Ⅱ score （APACHEⅡ） and multiple organ dysfunction score （Marshall）， rate of multiple organ dysfunction syndrome （MODS） within the first week after admission，pancreatic infection rate，and in-hospital mortality were compared between the two groups. Results Compared with the standard fluid therapy group on day 3 after admission，APACHEⅡ score and Marshall score decreased significantly in the early goal-directed fluid therapy group （APACHEⅡ score：7.38±4.01 versus 11.35±4.27， P=0.011；Marshall score：4.13±2.06 versus 6.82±3.15， P=0.016）. In addition，patients in the early goal-directed fluid therapy group experienced a trend toward lower rates of MODS with the first week after admission，pancreatic infection，and in-hospital mortality （rate of MODS：46.0% versus 61.8%，P=0.139；rate of pancreatic infection：31.7% versus 44.1%， P=0.226；in-hospital mortality：15.8% versus 23.5%，P=0.355） that did not reach statistical significance. Conclusion Although early goal-directed fluid therapy for SAP in acute response stage may have ameliorated the patient’s condition and improved outcome to a certain degree，carefully designed human clinical trials should be performed in a randomized controlled manner to assess the role of such fluid resuscitation in SAP.
This paper introduces the development and animal tests of a miniaturized electrical chest compression device. Based on pulse width modulation technology produced by micro control unit, the device can control the frequency and depth of the compression accurately, as well as perform real-time adjustment. Therefore, it can perform continuous and stable chest compression for long time, which may increase the successful rate of cardiopulmonary resuscitation (CPR). Besides, the device can also produce different types of compression waveforms, including trapezoidal and triangular waveforms. Then, the performance and efficacy of the device was assessed with a rat model of asphyxial cardiac arrest (CA).
The inspiratory impedance threshold device (ITD) was put forward by Lurie in 1995, and was assigned as a class Ⅱa recommendation by the International Liaison Committee on Resuscitation (ILCOR) resuscitation guidelines in 2005. The ITD is used to augment negative intrathoracic pressure during recoil of the chest so as to enhance venous return and cardiac output, and to decrease intracranial pressure. In the recent years many researches on the ITD have been1 carried out, but all the researches can not take out a clear evidence to support or refute the use of the ITD. This paper introduces the structure and working principle of the ITD in detail, the research results and the debates about the use of the ITD for the past years.
Sudden cardiac arrest is one of the critical clinical syndromes in emergency situations. A cardiopulmonary resuscitation (CPR) is a necessary curing means for those patients with sudden cardiac arrest. In order to simulate effectively the hemodynamic effects of human under AEI-CPR, which is active compression-decompression CPR coupled with enhanced external counter-pulsation and inspiratory impedance threshold valve, and research physiological parameters of each part of lower limbs in more detail, a CPR simulation model established by Babbs was refined. The part of lower limbs was divided into iliac, thigh and calf, which had 15 physiological parameters. Then, these 15 physiological parameters based on genetic algorithm were optimized, and ideal simulation results were obtained finally.
ObjectiveTo investigate the effects of different peak flow on the airway pressure to explore a preferable value of peak flow in ventilation during cardiopulmonary resuscitation (CPR) under volume control ventilation (VCV) mode and decreasing-wave. Methods30 patients who underwent CRP in the emergency unit between January 2012 and 2014 was recruited in the study. When the chest compressions came into a stable state by a same doctor,the peak flow was set at 50 L/min and 30 L/min respectively while other parameters fixed in the same patient. Then the pressure-time curve of a respiratory cycle was randomly frozen to achieve the highest peak pressure in inspiratory phase. ResultsThe highest peak airway pressures were (54.1±4.9)cm H2O and (35.5±5.3)cm H2O when the peak flow were set at 50 L/min and 30 L/min respectively with significant difference. The incidence of peak airway pressure greater than 40 cm H2O was 96.7% and 26.7%,and the incidence of peak airway pressure greater than 50 cm H2O was 76.7% and 0%,respectively. Compared with 50 L/min,the peak flow of 30 L/min obviously reduced the peak pressure (P=0.000). ConclusionIn the mechanical ventilation during CPR using VCV mode and decreasing-wave,compared with peak flow of 50 L/min,smaller peak flow of 30 L/min can significantly reduce peak airway pressure,and significantly reduce the adverse effects to ventilation by repeated violent changes in airway pressure caused by continuing chest compressions,and make airway peak pressure under 40 cm H2O in most patients,so it is a reasonable and safe choice.
ObjectiveTo determine the effects of different volume fluid resuscitation on intestinal injury and the permeability of intestine in hemorrhagic shock rats. MethodsSprague-Dawley male rats(n=72) were randomly equally divided into 4 groups after the model establishment of blood pressure-controlled hemorrhage, 45, 30, and 15 mL/(kg·h) of fluid resuscitation were performed in high dosage of resuscitation(HLR), moderate dosage of resuscitation(MLR), and low dosage of resuscitation(LLR) group respectively, but rats of Sham group didn't accept fluid resuscitation. After resuscitation, ten centimeters ileum was harvested for testing intestinal permeability. Then 6 rats of each group were sacrificed at 24, 48, and 72 hours after fluid resuscitation respectively. Over the specified time interval, blood was collected for testing levels of lactic acid and plasma tumor necrosis factor-α(TNF-α). The ileums of 3 resuscitation groups were obtained for testing the ratio of wet weight to dry weight and observing the histological changes. ResultsAfter resuscitation, the intestinal permeability was higher in HLR group(P<0.05). At 3-8 hours after resuscitation, rats of Sham group were all died, and the other rats of 3 groups were all alive. The level of plasma lactic acid was lower in LLR group than those of other 2 groups at 24 hours(P<0.05). The levels of TNF-α were higher in HLR group than those of other 2 groups at 24, 48, and 72 hours(P<0.05), and at 48 hours, level of TNF-α in LLR group was lower than MLR group(P<0.05). At 24 hours after resuscitation, ratio of intestinal wet weight to dry weight in LLR group was the lowest, and HLR group was the highest(P<0.05). According to the histopathology, intestinal injuries of the 3 groups were tend to be remission with the time, and at 48 and 72 hours after resuscitation, intestinal villus of LLR group appeared to be normal. ConclusionLimited fluid resuscitation of 15 mL/(kg·h) could not only decrease the levels of lactic acid and TNF-α, but also moderate the intestinal permeability and the intestinal injury in early stage after shock and surgery.
From aortic declamping to weaning from cardiopulmonary bypass (CPB), myocardium needs recovery not only from surgical and ischemia/reperfusion injury, but also of its full performance of pumping function as quickly as possible. In the early period of resuming myocardial perfusion, coronary blood flow should be increased, but ventricular volume overload, large dosage of adrenaline and isoprenaline, and high-energy defibrillation should be avoided. Thenappropriate management according to cardiac function and ECG changes is needed for successful weaning from CPB.