The Experts below are selected from a list of 39 Experts worldwide ranked by ideXlab platform

Yi-jun Deng - One of the best experts on this subject based on the ideXlab platform.

  • The comparison of dexmedetomidine and morphine on respiratory mechanics in patients with chronic obstructive pulmonary disease during mechanical ventilation
    International Journal of Anesthesiology and Resuscitation, 2013
    Co-Authors: Yi-jun Deng
    Abstract:

    Objective To study the effect of dexmedetomidine(DEX) and morphine hydrochloride on respiratory mechanics in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) undergoing mechanical ventilation.Methods Forty patients of AECOPD with respiratory failure undergoing mechanically ventilated were randomly divided into two groups (n=20).The control group were treated with morphine for sedation while the experimental group with DEX.APACHE Ⅱ score,bispectral index (BIS) score,ramsay score were recorded.Respiratory mechanical parameters after sedation,and changes in vital signs as well as blood gas were compared before and after sedation.Results Compared with the control group,the mean arterial Pressure (MAP) and pulse in the experimental group were decreased after sedation[(80±3) mm Hg vs (75±4) mm Hg(1 mm Hg=0.133 kPa),(90±3) bpm vs (79±3) bpm](P＜0.01).The mean airway Pressure(Paw) and plateau Pressure(Pplat) were significantly downregulated in experimental group [(7.5±0.7) cm H2O vs (6.2±0.6) cm H2O (1 cm H2O=0.098 kPa),(19.8±1.7) cm H2O vs (18.0±1.1) cm H2O] (P＜0.05).peak esophageal Pressure (PPEAK ES) and the peak esophageal manometry reference Esophagus Pressure difference (dPES) was increased [(-3.4±0.7) cm H2O vs (-5.4±1.0) cm H2O,(-6.9±1.0) cm H2O vs (-9.8±1.3) cm H2O] (P＜0.01).There were no significant difference between the two groups in folding screen the end of the suction gas during transpulmonary Pressure (Ptp Plat) and pulmonary static compliance (Cst)[(25.5±2.3) cm H2O vs (26.0±2.6) cm H2O,(20.5±1.9)em H2O vs (20.1±1.2) cm H2O].The airway resistance (Raw)[(20.3±0.9) cm H2O·L-1·s-1 vs (15.6±1.4) cm H2O·L1·s-1](P＜0.01)and mechanical work of breathing (WOBv)[(0.49±0.10) j/L vs (0.43±0.06) j/L](P＜0.05) were increased.The patient work of breathing (WOBp) was significantly increased [(0.11 ±0.02)j/L vs (0.16±0.04)j/L] (P＜0.01).The time of mechanical ventilation and the intensive care unit (ICU)staying time were reduced [(76±5) h vs (64±3) h、(6.0±1.5) d vs (4.6±0.9) d](P＜0.05).Conclusions DEX increased the sedative effect and lung compliance,and decreased Raw in patients undergoing mechanical ventilation compared with morphine.DEX would also unload respiratory muscle oxygen consumption estimated by reducing the inspiratory load and work of breathing. Key words: Dexmedetomidine;  Chronic obstructive pulmonary disease;  Mechanical ventilation;  Respiratory mechanics

Nanshan Zhong - One of the best experts on this subject based on the ideXlab platform.

  • The relationship between mouth Pressure or tracheal Pressure and Esophagus Pressure and diaphragmatic Pressure
    Zhonghua jie he he hu xi za zhi = Zhonghua jiehe he huxi zazhi = Chinese journal of tuberculosis and respiratory diseases, 2006
    Co-Authors: Zeguang Zheng, Rongchang Chen, Feng-quan Yang, Xing-jie Zhang, Jing-ping Zheng, Nanshan Zhong
    Abstract:

    Objective To investigate the relationship between mouth Pressure(Pmo) or tracheal Pressure(Ptr) and Esophagus Pressure(Pes) or transdiaphragmatic Pressure.Methods Seventeen patients were involved in the study.Maximal inspiratory Pressure(MIP),maximal trandiaphragmatic Pressure(Pdi_(max)),maximal Esophagus Pressure(Pes_(max)),twitch mouth Pressure(TwPmo),twitch transdiaphragmatic Pressure(TwPdi) and twitch Esophagus Pressure(TwPes) were measured before narcotization as a normal procedure for the abdominal operation and twitch tracheal Pressure(TwPtr_(nar)),twitch Esophagus Pressure(TwPes_(nar)) and twitch transdiaphragmatic Pressure(TwPdi_(nar)) were dynamically monitored during narcotization.Results (1)The correlation coefficient(r) values between Pdi_(max) and MIP,TwPdi and TwPmo,TwPdi_(nar) and TwPtr_(nar),Pes_(max) and MIP,TwPes and TwPmo,TwPes_(nar) and TwPtr_(nar) were 0.976±0.030,0.816±0.155,0.923±0.446,0.981±0.185,0.829±0.168 and 0.955±0.292,respectively.(2)The coefficient variation(CV) of MIP,Pes_(max),Pdi_(max),TwPmo,TwPes and TwPdi were(14.2±4.7)%,(15.2±4.3)%,(15.5±4.1)%,(30.4±15.9)%,(10.8±5.1)% and(9.9±4.0)%,respectively.The CV of TwPmo was the highest(compare with others,all P0.05) and that of TwPes and TwPdi was the lowest(compare with others,all P0.05).There was no significant difference among MIP,Pes_(max) and Pdi_(max)(P0.05).(3)The r value between the changing values of TwPtr_(nar) and TwPdi_(nar) or TwPes_(nar) during narcotization were 0.839 or 0.894(P=0.000,respectively).Conclusion The measurement of MIP and TwPmo should be repeated and the highest value should be chosen in order to reduce the possibility of underestimating the function of diaphragm,which could be dynamically monitored by TwPtr_(nar).

Xin-zhi Weng - One of the best experts on this subject based on the ideXlab platform.

  • The effects of extrinsic positive end-expiratory Pressure on work of breathing in patients with chronic obstructive pulmonary disease
    Chinese Journal of Internal Medicine, 2001
    Co-Authors: Kong W, Yuanhua Yang, Kewu Huang, Jiang C, Chunxue Wang, Xin-zhi Weng
    Abstract:

    OBJECTIVE: To study the effect of extrinsic positive end-expiratory Pressure(PEEPe) on work of breathing in chronic obstructive pulmonary disease (COPD) patients and its mechanism. METHODS: 10 ventilated patients [4 males and 6 females with mean age of (70.1 +/- 5.5) years] with exacerbation of COPD were admitted into the study. All the patients' cardiopulmonary functions were stable, and they could receive Pressure support ventilation (PSV). Patients with sever heart dysfunction, hepatic dysfunction, renal dysfunction or fever were ruled out. Each patient had an Esophagus balloon Pressure sensor inserted, and the Esophagus balloon was properly positioned using "occlusion test". Flow sensor was placed at the end of tracheal tube opening. Then Esophagus balloon Pressure sensor and flow sensor were connected with Bicore CP-100 pulmonary monitor. Dynamic intrinsic positive end-expiratory Pressure (PEEPi, dyn), difference of Esophagus Pressure (dPes), work of breathing patient (WOBp), work of breathing ventilator (WOBv), Pressure time product (PTP), tidal volume (Vt), respiratory rate (RR), minute ventilation (MV), peak inspiratory flow rate (PIFR), peak expiratory flow rate (PEFR), expiratory airway resistance (Rawe), fraction of inspiration (Ti/Ttot) and so on were measured. PEEPi,dyn was measured by Esophagus balloon technique. Electrocardiogram and noninvasive blood Pressure modes were added to HP M1165A monitor. Heart rate (HR) and blood Pressure (BP) were also measured. Arterial blood was analyzed to measure pH, partial Pressure of oxygen in arterial blood (PaO(2)), partial Pressure of carbon dioxide in arterial blood (PaCO(2)) and saturation of arterial blood oxygen (SaO(2)). At first, PEEPi, dyn was measured when PEEPe was zero, which was called PEEPi, dynz and was set as baseline. Then PEEPe was set randomly, which was 0%, 40%, 60%, 80% and 100% of PEEPi, dynz respectively. Other parameters remained stable. All the indexes were measured 30 minutes after the level of PEEPe was changed. RESULTS: WOBp decreased as PEEPe increased, from (1.08 +/- 0.49) J/L of PEEPe-0% of PEEPi,dynz to (0.57 +/- 0.32) J/L of PEEPe-100% of PEEPi, dynz, and significant difference was found between each level of PEEPe and the baseline (P < 0.01). But we didn't find significant difference between PEEPe-80% of PEEPi,dynz and PEEPe-100% of PEEPi, dynz. WOBv increased significantly as PEEPe increased, from (1.50 +/- 0.47) J/L of PEEPe-0% of PEEPi, dynz to (1.82 +/- 0.56) J/L of PEEPe-80% of PEEPi, dynz and (1.85 +/- 0.48) J/L of PEEPe-100% of PEEPi,dynz(P < 0.01). The total WOB (WOBp + WOBv) remained steady. PTP trended to decrease, from (153.6 +/- 76.8) cm H(2)O x s x m(-1) of PEEPe-0% of PEEPi, dynz to (86.9 +/- 45.9) cm H(2)O x s x m(-1) of PEEPe-100% of PEEPi, dynz; the difference of PTP between PEEPe-40% of PEEPi,dynz and PEEPe-0% of PEEPi, dynz was significant(P < 0.05), the differences between other levels of PEEPe and PEEPe-0% of PEEPi, dynz were very significant (P < 0.01), but no significant difference was found between PEEPe-80% of PEEPi, dynz and PEEPe-100% of PEEPi, dynz. PEEPi,dyn also decreased significantly as PEEPe increased, from (7.70 +/- 1.42) cm H(2)O of PEEPe-0% of PEEPi, dynz to (2.10 +/- 0.57) cm H(2)O of PEEPe-100% of PEEPi, dynz, very significant differences were found between each level of PEEPe and the baseline (P < 0.01). Significant positive linear correlation was found between DeltaWOBp and DeltaPEEPi, dyn were(r = 0.609, P < 0.01, n = 10). dPes decreased as PEEPe increased, from (15.20 +/- 4.16) cm H(2)O of PEEPe-0% of PEEPi, dynz to (8.20 +/- 4.13) cm H(2)O of PEEPe-100% of PEEPi, dynz, and very significant differences were found between each level of PEEPe and the baseline (P < 0.01). But the difference between PEEPe-80% of PEEPi, dynz and PEEPe-100% of PEEPi, dynz wasn't significant, even dPes of PEEPe-100% of PEEPi, dynz was higher than that of PEEPe-80% of PEEPi, dynz. Vt didn't change markedly. RR, MV and f/Vt increased slightly. Both PIFR and PEFR didn't change markedly. At the same time, HR, BP and blood gas analysis were investigated, but no significant change was found. CONCLUSION: PEEPe can reduce WOBp significantly and improve the coordination between the patient and ventilator. It is shown that decrement of Pressure difference between alveolar and central airway leads to decrement of WOBp.

Zeguang Zheng - One of the best experts on this subject based on the ideXlab platform.

  • The relationship between mouth Pressure or tracheal Pressure and Esophagus Pressure and diaphragmatic Pressure
    Zhonghua jie he he hu xi za zhi = Zhonghua jiehe he huxi zazhi = Chinese journal of tuberculosis and respiratory diseases, 2006
    Co-Authors: Zeguang Zheng, Rongchang Chen, Feng-quan Yang, Xing-jie Zhang, Jing-ping Zheng, Nanshan Zhong
    Abstract:

    Objective To investigate the relationship between mouth Pressure(Pmo) or tracheal Pressure(Ptr) and Esophagus Pressure(Pes) or transdiaphragmatic Pressure.Methods Seventeen patients were involved in the study.Maximal inspiratory Pressure(MIP),maximal trandiaphragmatic Pressure(Pdi_(max)),maximal Esophagus Pressure(Pes_(max)),twitch mouth Pressure(TwPmo),twitch transdiaphragmatic Pressure(TwPdi) and twitch Esophagus Pressure(TwPes) were measured before narcotization as a normal procedure for the abdominal operation and twitch tracheal Pressure(TwPtr_(nar)),twitch Esophagus Pressure(TwPes_(nar)) and twitch transdiaphragmatic Pressure(TwPdi_(nar)) were dynamically monitored during narcotization.Results (1)The correlation coefficient(r) values between Pdi_(max) and MIP,TwPdi and TwPmo,TwPdi_(nar) and TwPtr_(nar),Pes_(max) and MIP,TwPes and TwPmo,TwPes_(nar) and TwPtr_(nar) were 0.976±0.030,0.816±0.155,0.923±0.446,0.981±0.185,0.829±0.168 and 0.955±0.292,respectively.(2)The coefficient variation(CV) of MIP,Pes_(max),Pdi_(max),TwPmo,TwPes and TwPdi were(14.2±4.7)%,(15.2±4.3)%,(15.5±4.1)%,(30.4±15.9)%,(10.8±5.1)% and(9.9±4.0)%,respectively.The CV of TwPmo was the highest(compare with others,all P0.05) and that of TwPes and TwPdi was the lowest(compare with others,all P0.05).There was no significant difference among MIP,Pes_(max) and Pdi_(max)(P0.05).(3)The r value between the changing values of TwPtr_(nar) and TwPdi_(nar) or TwPes_(nar) during narcotization were 0.839 or 0.894(P=0.000,respectively).Conclusion The measurement of MIP and TwPmo should be repeated and the highest value should be chosen in order to reduce the possibility of underestimating the function of diaphragm,which could be dynamically monitored by TwPtr_(nar).

Kong W - One of the best experts on this subject based on the ideXlab platform.

  • The effects of extrinsic positive end-expiratory Pressure on work of breathing in patients with chronic obstructive pulmonary disease
    Chinese Journal of Internal Medicine, 2001
    Co-Authors: Kong W, Yuanhua Yang, Kewu Huang, Jiang C, Chunxue Wang, Xin-zhi Weng
    Abstract:

    OBJECTIVE: To study the effect of extrinsic positive end-expiratory Pressure(PEEPe) on work of breathing in chronic obstructive pulmonary disease (COPD) patients and its mechanism. METHODS: 10 ventilated patients [4 males and 6 females with mean age of (70.1 +/- 5.5) years] with exacerbation of COPD were admitted into the study. All the patients' cardiopulmonary functions were stable, and they could receive Pressure support ventilation (PSV). Patients with sever heart dysfunction, hepatic dysfunction, renal dysfunction or fever were ruled out. Each patient had an Esophagus balloon Pressure sensor inserted, and the Esophagus balloon was properly positioned using "occlusion test". Flow sensor was placed at the end of tracheal tube opening. Then Esophagus balloon Pressure sensor and flow sensor were connected with Bicore CP-100 pulmonary monitor. Dynamic intrinsic positive end-expiratory Pressure (PEEPi, dyn), difference of Esophagus Pressure (dPes), work of breathing patient (WOBp), work of breathing ventilator (WOBv), Pressure time product (PTP), tidal volume (Vt), respiratory rate (RR), minute ventilation (MV), peak inspiratory flow rate (PIFR), peak expiratory flow rate (PEFR), expiratory airway resistance (Rawe), fraction of inspiration (Ti/Ttot) and so on were measured. PEEPi,dyn was measured by Esophagus balloon technique. Electrocardiogram and noninvasive blood Pressure modes were added to HP M1165A monitor. Heart rate (HR) and blood Pressure (BP) were also measured. Arterial blood was analyzed to measure pH, partial Pressure of oxygen in arterial blood (PaO(2)), partial Pressure of carbon dioxide in arterial blood (PaCO(2)) and saturation of arterial blood oxygen (SaO(2)). At first, PEEPi, dyn was measured when PEEPe was zero, which was called PEEPi, dynz and was set as baseline. Then PEEPe was set randomly, which was 0%, 40%, 60%, 80% and 100% of PEEPi, dynz respectively. Other parameters remained stable. All the indexes were measured 30 minutes after the level of PEEPe was changed. RESULTS: WOBp decreased as PEEPe increased, from (1.08 +/- 0.49) J/L of PEEPe-0% of PEEPi,dynz to (0.57 +/- 0.32) J/L of PEEPe-100% of PEEPi, dynz, and significant difference was found between each level of PEEPe and the baseline (P < 0.01). But we didn't find significant difference between PEEPe-80% of PEEPi,dynz and PEEPe-100% of PEEPi, dynz. WOBv increased significantly as PEEPe increased, from (1.50 +/- 0.47) J/L of PEEPe-0% of PEEPi, dynz to (1.82 +/- 0.56) J/L of PEEPe-80% of PEEPi, dynz and (1.85 +/- 0.48) J/L of PEEPe-100% of PEEPi,dynz(P < 0.01). The total WOB (WOBp + WOBv) remained steady. PTP trended to decrease, from (153.6 +/- 76.8) cm H(2)O x s x m(-1) of PEEPe-0% of PEEPi, dynz to (86.9 +/- 45.9) cm H(2)O x s x m(-1) of PEEPe-100% of PEEPi, dynz; the difference of PTP between PEEPe-40% of PEEPi,dynz and PEEPe-0% of PEEPi, dynz was significant(P < 0.05), the differences between other levels of PEEPe and PEEPe-0% of PEEPi, dynz were very significant (P < 0.01), but no significant difference was found between PEEPe-80% of PEEPi, dynz and PEEPe-100% of PEEPi, dynz. PEEPi,dyn also decreased significantly as PEEPe increased, from (7.70 +/- 1.42) cm H(2)O of PEEPe-0% of PEEPi, dynz to (2.10 +/- 0.57) cm H(2)O of PEEPe-100% of PEEPi, dynz, very significant differences were found between each level of PEEPe and the baseline (P < 0.01). Significant positive linear correlation was found between DeltaWOBp and DeltaPEEPi, dyn were(r = 0.609, P < 0.01, n = 10). dPes decreased as PEEPe increased, from (15.20 +/- 4.16) cm H(2)O of PEEPe-0% of PEEPi, dynz to (8.20 +/- 4.13) cm H(2)O of PEEPe-100% of PEEPi, dynz, and very significant differences were found between each level of PEEPe and the baseline (P < 0.01). But the difference between PEEPe-80% of PEEPi, dynz and PEEPe-100% of PEEPi, dynz wasn't significant, even dPes of PEEPe-100% of PEEPi, dynz was higher than that of PEEPe-80% of PEEPi, dynz. Vt didn't change markedly. RR, MV and f/Vt increased slightly. Both PIFR and PEFR didn't change markedly. At the same time, HR, BP and blood gas analysis were investigated, but no significant change was found. CONCLUSION: PEEPe can reduce WOBp significantly and improve the coordination between the patient and ventilator. It is shown that decrement of Pressure difference between alveolar and central airway leads to decrement of WOBp.