ObjectiveTo evaluate the effect of positive end-expiratory pressure (PEEP) on respiratory function and hemodynamics in acute lung injury (ALI) with intra-abdominal hypertension (IAH). MethodsSix pigs were anesthetized and received mechanical ventilation (MV). Volume controlled ventilation was set with tidal volumn(VT) of 8 mL/kg,respiratory rate(RR) of 16 bpm,inspired oxygen concentration (FiO2) of 0.40,and PEEP of 5 cm H2O. ALI was induced by repeated lung lavage with diluted hydrochloric acid (pH<2.5) until PaO2/FiO2 declined to 150 mm Hg or less to established ALI model. Intra-abdominal hypertension was induced by an nitrogen inflator to reach intra-abdominal pressure of 20 mm Hg. Respiratory parameters and hemodynamics were continuously recorded at different PEEP levels(5,10,15,and 20 cm H2O). Every level was maintained for one hour. ResultsPaO2/FiO2 in PEEP5,10,15 and 20 were 90±11,102±10,172±23 and 200±34 mm Hg respectively. PaO2/FiO2 in PEEP15 and 20 were significantly higher than those in PEEP5 and 10 (P<0.05). Chest wall compliance (Ccw) in PEEP5,15 and 20 were 26±3,76±15 and 85±14 mL/cm H2O respectively. Ccw in PEEP15 and 20 were significantly higher than those in PEEP5 (P<0.05). There was no significant difference in lung compliance (CL) in different PEEP levels (P>0.05). Plateau pressure(Pplat) in PEEP5,10,15 and 20 were 30±3,31±2,36±2 and 38±4 cm H2O respectively. Pplat in PEEP15 and 20 were significantly higher than those in PEEP5 and 10 (P<0.05). There was no significant difference in Pplat between PEEP15 and 20 (P>0.05). Heart rate (HR) in PEEP5,15 and 20 were 113±17,147±30,and 160±30 beat/min respectively. HR in PEEP15 and 20 were significantly higher than those in PEEP5 (P<0.05). There was no significant difference in HR between PEEP15 and 20 (P>0.05).Cardiac index (CI) in PEEP5 and 20 were 4.5±0.6 and 3.5±0.6 L·min-1·m-2 respectively. CI in PEEP20 was significantly lower than that in PEEP5 (P<0.05). There was no significant difference in CI in PEEP5,10 or 15(P>0.05). Central venous pressure(CVP) in PEEP5,15 and 20 were 12±2,17±2,and 18±3 mm Hg respectively. CVP in PEEP15 and 20 were significantly higher than those in PEEP5 (P<0.05). There was no significant difference in CVP between PEEP15 and 20 (P>0.05). There were no significant differences in MAP,SVRI,ITBVI,GEDI,PVPI,or EVLWI between different PEEP levels. ConclusionConcomitant ALI and IAH can induce great impairments in respiratory physiology. When PEEP is gradually increased,oxygenation and the respiratory function are improved without significant secondary hemodynamic disturbances.
ObjectiveTo investigate the safety and efficacy of intermittent pneumatic compression (IPC) in the treatment of deep venous thrombosis (DVT). MethodsThe clinical data of 496 patients with DVT who were treated in our hospital from January 2010 to October 2014 were analyzed retrospectively, to compare the time of venous pressure decreased to normal (T1) and time of circumference difference decreased to normal (T2) in patients received pure therapy (control group) and pure therapy combined with IPC (combination group), according to different types of patients in acute, sub-acute, and chronic phase. In addition, comparison of the remission rate of pulmonary embolism (PE), incidence of PE, and recurrence of DVT was performed between the control group and combination group too. Results① For DVT patients in acute stage, the time of T1 and T2 of patients in central type, peripheral type, and mixed type who received anticoagulant therapy/systemic thrombolysis/catheter thrombolysis+IPC, were significantly shorter than those patients who received only anticoagulant therapy/systemic thrombolysis/catheter thrombolysis (P<0.05). For DVT patients in sub-acute stage, the time of T1 and T2 of patients in central type and mixed type who received anticoagulant therapy/systemic thrombolysis+IPC, were significantly shorter than those of patients who received only anticoagulant therapy/systemic thrombolysis (P<0.05), the time of T1 of patients in peripheral type who received anticoagulant therapy/systemic thrombolysis+IPC, were significantly shorter than those of patients who received only anticoagulant therapy/systemic thrombolysis (P<0.01), but the time of T2 of patients in peripheral type didn't differed between patients who received only anticoagulant therapy/systemic thrombolysis and anticoagulant therapy/systemic thrombolysis +IPC (P>0.05). For DVT patients in chronic stage, the time of T1 and T2 of patients in central type and mixed type didn't differed between patients who received only anticoagulant therapy and anticoagulant therapy +IPC (P>0.05); the time of T1 of patients in peripheral type who received anticoagulant therapy+IPC, were significantly shorter than those of patients who received only anticoagulant therapy (P<0.05), but the time of T2 didn't differed with each other (P>0.05). ② There were 63 patients in control group and 47 patients in combination group had PE before treatment. After the treatment, the PE symptom of control group relieved in 56 patients (88.89%, 56/63) and maintained in 7 patients (11.11%, 7/63), the symptom of combination group relieved in 44 patients (93.62%, 44/47) and maintained in 3 patients (6.38%, 3/47), so the remission rate of PE symptom in combination group was higher (P<0.05). There were 6 patients suffered from new PE in control group[4.26% (6/141)] and 0 in combination group[0 (0/245)] after treatment in patients who hadn't PE before treatment, and the incidence of PE was lower in combination group (P<0.05). ③ There were 325 patients were followed up for 3-36 months with the median time of 27 months, including 157 patents in control group and 168 patients in combination group. During the follow-up period, 74 patients recurred[47.13% (74/157)] in control group and 46 patients recurred[27.38% (46/168)] in combination group, and the recurrence rate was lower in combination group (P<0.05). In addition, 41 patients suffered from post-thrombotic syndrome[26.11% (41/157)] in control group and 27 patients[16.07% (27/168)] in combination group, and the incidence of post-thrombotic syndrome was lower in combination group (P<0.05). ConclusionsIPC can significantly shorten the time of venous pressure and the circumference difference decreased to normal for DVT patients in acute stage and majority DVT patients in sub-acute stage, and it can relieve the clinical symptoms of PE, reduce the incidence rate of PE and recurrence rate of DVT. Therefore, IPC is a safe, reliable, and effective treatment for DVT patients in acute stage and majority DVT patients in sub-acute stage.
To evaluate the influence of different brands of syringes on performance parameters and application quality of syringe pump, we carried out matching experiment of infusion/syringe pump analyzer Rigel Multi-Flo, made by ALK Co. in Sweden, for 3 different types of syringes to measure the flow rate, occlusion alarm pressure, occlusion time and bolus volume of 26 syringe pumps. Data of quality control were analyzed with statistical method. The results demonstrated that there were significant differences in the flow rate, occlusion alarm pressure, occlusion time and bolus volume (P<0.01) between those of common syringes and original syringes. This study points out that the health care providers should select compatible syringes for syringe pumps, which provides evidence and guidance to assure the reasonable and safe application of syringe pumps in clinical practice.
Objective To study the influence of low-tidal volume and positive end expiratory pressure (PEEP) protective ventilation on cardiac output volume in elderly patients under general anesthesia. Methods From August 2012 to July 2014, 60 elderly patients undergoing selective surgery were divided into three groups with 20 patients in each. Group A was treated with conventional ventilation: tidal volume at 8 mL/kg, PEEP at 0 cm H2O (1 cm H2O=0.098 kPa); group B was treated with a tidal volume of 6 mL/kg and a PEEP of 5 cm H2O; group C was treated with a tidal volume of 6 mL/kg and a PEEP of 8 cm H2O. We then observed and analyzed the blood pressure, heart rate, cardiac output, arterial blood gas and airway mean pressure before induction of anesthesia (T0), 15 minutes of mechanical ventilation after the induction of anesthesia (T1), 60 minutes after anesthesia induction (T2), and 15 minutes after tracheal extubation (T3). Results In all the three groups, the mean arterial pressure and cardiac output were stable. In group B and C, central venous pressure increased significantly, the mean airway pressure and lung compliance increased, and the arterial oxygen branch pressure also increased significantly (P < 0.05). Conclusion Low-tidal volume combined with 5-cm H2O or 8-cm H2O positive end expiratory pressure lung-protective ventilation had a small influence on the cardiac output of elderly patients under anesthesia, which can be safely used.
Objective To observe the characteristics of changes of 24hour ambulatory blood pressure and heart rate of 50 patients with anterior ischemic optic neuropathy (AION). Methods Fifty patients with AION and the persons without in the control group, which had the same number, gender and age as the patients with AION, underwent 24-hour ambulatory blood pressure and heart rate measurement. Results Both groups had no difference in mean blood pressure and heart rate during the daytime (t=1.25,0.93; P＞0.05), higher than those in the nighttime (t=3.63,3.16; P＜0.05). Mean blood pressure and heart rate of AION group at night were lower than those of the control group (t=3.82,1.77; P＜0.01,0.05), especially diastolic pressure of AION group was lower than that of the control group from 2 am to 7 am (P＜0.01), as well as the heart rate from 2 am to 5 am (P＜0.05 or P＜0.01). The curves of blood pressure of AION group showed more gradual and fluctuant rising, while those of the control group showed sharper and less fluctuant rising. Conclusion According to the curves of blood pressure rising, the patients with AION may have some defects in auto-regulatory mechanism of blood pressure. The low spots of blood pressure and heart rate in early morning, which might be a critical point leading to AION. (Chin J Ocul Fundus Dis, 2002, 18: 259-261)
Objective To investigate the effects of long time different negative pressures on osteogenic diffe-rentiation of rabbit bone mesenchymal stem cells (BMSCs). Methods The rabbit BMSCs were isolated and cultured by density gradient centrifugation. Flow cytometry was used to analyze expression of surface markers. The third passage cells cultured under condition of osteogenic induction and under different negative pressure of 0 mm Hg (control group), 75 mm Hg (low negative pressure group), and 150 mm Hg (high negative pressure group) (1 mm Hg=0.133 kPa), and the negative pressure time was 30 min/h. Cell growth was observed under phase contrast microscopy, and the growth curve was drawn; alkaline phosphatase (ALP) activity was detected by ELISA after induced for 3, 7, and 14 days. The mRNA and protein expressions of collagen type I (COL-I) and osteocalcin (OC) in BMSCs were analyzed by real-time fluorescence quantitative PCR and Western blot. Results The cultured cells were identified as BMSCs by flow cytometry. The third passage BMSCs exhibited typical long shuttle and irregular shape. Cell proliferation was inhibited with the increase of negative pressure. After induced for 4 days, the cell number of high negative pressure group was significantly less than that in control group and low negative pressure group (P<0.05), but there was no significant difference between the low negative pressure group and the control group (P>0.05); at 5-7 days, the cell number showed significant difference between 3 groups (P<0.05). The greater the negative pressure was, the greater the inhibition of cell proliferation was. There was no significant difference in ALP activity between groups at 3 days after induction (P>0.05); the ALP activity showed significant difference (P<0.05) between the high negative pressure group and the control group at 7 days after induction; and significant difference was found in the ALP activity between 3 groups at 14 days after induction (P<0.05). The greater the negative pressure was, the higher the ALP activity was. Real-time fluorescence quantitative PCR and Western blot detection showed that the mRNA and protein expressions of COL-I and OC protein were significantly higher in low negative pressure group and high negative pressure group than control group (P<0.05), and in the high negative pressure group than the low negative pressure group (P<0.05). Conclusion With the increase of the negative pressure, the osteogenic differentiation ability of BMSCs increases gradually, but the cell proliferation is inhibited.
Objective Sedation and/or analgesia is often applied during noninvasive positive pressure ventilation (NIPPV) to make patients comfortable, and thus improve the synchronization between patients and ventilator. Nevertheless, the effect of sedation and/or analgesia on the clinical outcome of the patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) after extubation remains controversial. Methods A retrospective study was conducted on patients with AECOPD who received NIPPV after extubation in seven intensive care units in West China Hospital, Sichuan University between December 2013 and December 2017 . A logistic regression model was used to analyze the association between the use of sedation and/or analgesia and clinical outcomes including rate of NIPPV failure (defined as the need for reintubation and mechanical ventilation), hospital mortality, and length of intensive care unit stay after extubation. Results A total of 193 patients were included in the analysis, and 62 cases of these patients received sedation and/or analgesia during NIPPV. The usage of sedation and/or analgesia could result in failure of NIPPV (adjusted odd ratio [OR] 0.10, 95% confidence interval [CI] 0.02 - 0.52, P=0.006) and death (adjusted OR=0.13, 95%CI 0.04 - 0.42, P=0.001). Additionally, intensive care unit stay after extubation was longer in the patients who did not receive sedation and/or analgesia than those who did (11.02 d vs. 6.10 d, P< 0.01). Conclusion The usage of sedation and/or analgesia during NIPPV can decrease both the rate of NIPPV failure and hospital mortality in AECOPD patients after extubation.
ObjectiveTo investigate the clinical effect of combined air pressure wave and oral glucosamine in the treatment of knee osteoarthritis. MethodsWe chose 200 patients with knee osteoarthritis treated in the Department of Rehabilitation between April 2013 and March 2015 as our research subjects. The patients were randomly divided into observation group and control group with 100 in each. The control group accepted conventional physical therapy, while the observation group underwent normal physical therapy in combination with air pressure wave and oral glucosamine treatment. We compared the two groups in terms of curative effects. ResultsThe total effective rate was not significantly different between the two groups (P＞0.05) , but in terms of efficiency rate, the observation group (85.0%) was significantly superior to the control group (73.0%) (P ＜ 0.05) . ConclusionCombined air pressure wave and oral glucosamine treatment for knee osteoarthritis is high efficient, which is worthy of being popularized.
Simulation of the human biological lung is a crucial method for medical professionals to learn and practice the use of new pulmonary interventional diagnostic and therapeutic devices. The study on ventilation effects of the simulation under positive pressure ventilation mode provide valuable guidance for clinical ventilation treatment. This study focused on establishing an electrical simulation ventilation model, which aims to address the complexities in parameter configuration and slow display of air pressure and airflow waveforms in simulating the human biological lung under positive pressure ventilation mode. A simulated ventilation experiment was conducted under pressure-regulated volume control (PRVC) positive pressure ventilation mode, and the resulting ventilation waveform was compared with that of normal adults. The experimental findings indicated that the average error of the main reference index moisture value was 9.8% under PRVC positive pressure ventilation mode, effectively simulating the ventilatory effect observed in normal adults. So the established electrical simulation ventilation model is feasible, and provides a foundation for further research on the simulation of human biological lung positive pressure ventilation experimental platform.
ObjectiveTo investigate the methodology of a newly developed highpressure liquid chromatography electrochemical system in urinary 8hydroxydeoxyguanosine (8OHdG) quantification. MethodsQuantification of urinary 8OHdG with ESA 5600 Coularray system among 21 children from liver cancer highrisk areas, Fusui country, in contrast with 63 controls from Nanning city, Guangxi province.ResultsThe resolution, sensitivity, linearity, precision and recovery of this approach all fully meet the requirement of routine urinary 8OHdG quantification. The mean 8OHdG level of this population was (5.26±0.41) ng/mg creatinine, higher than previous report 〔(4.62±0.091) ng/mg creatinine〕 by similar method.ConclusionWith cautious design and modification, this method is reliable and accurate in high throughput quantification of urinary 8OHdG.