BACKGROUND: Partial pressure of end-tidal carbon dioxide(PETCO2) has been used to monitor the effectiveness of precordial compression(PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation...BACKGROUND: Partial pressure of end-tidal carbon dioxide(PETCO2) has been used to monitor the effectiveness of precordial compression(PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation(CPR). This study was to investigate changes of PETCO2 during CPR in rats with ventricular fi brillation(VF) versus asphyxial cardiac arrest.METHODS: Sixty-two male Sprague-Dawley(SD) rats were randomly divided into an asphyxial group(n=32) and a VF group(n=30). PETCO2 was measured during CPR from a 6-minute period of VF or asphyxial cardiac arrest.RESULTS: The initial values of PETCO2 immediately after PC in the VF group were signifi cantly lower than those in the asphyxial group(12.8±4.87 mmHg vs. 49.2±8.13 mmHg, P=0.000). In the VF group, the values of PETCO2 after 6 minutes of PC were significantly higher in rats with return of spontaneous circulation(ROSC), compared with those in rats without ROSC(16.5±3.07 mmHg vs. 13.2±2.62 mmHg, P=0.004). In the asphyxial group, the values of PETCO2 after 2 minutes of PC in rats with ROSC were signifi cantly higher than those in rats without ROSC(20.8±3.24 mmHg vs. 13.9±1.50 mmHg, P=0.000). Receiver operator characteristic(ROC) curves of PETCO2 showed signifi cant sensitivity and specifi city for predicting ROSC in VF versus asphyxial cardiac arrest.CONCLUSIONS: The initial values of PETCO2 immediately after CPR may be helpful in differentiating the causes of cardiac arrest. Changes of PETCO2 during CPR can predict outcomes of CPR.展开更多
Background: We investigated the differences between partial pressure of arterial carbon dioxide and end-tidal carbon dioxide (P(a-ET)CO2) with respect to the Broca-Katsura index (BKI), which is an obesity index, in ob...Background: We investigated the differences between partial pressure of arterial carbon dioxide and end-tidal carbon dioxide (P(a-ET)CO2) with respect to the Broca-Katsura index (BKI), which is an obesity index, in obese patients during general anesthesia. Materials and Methods: From January 2003 to December 2013, we studied 601 patients aged 16 years old or over undergoing general anesthesia. Patients had American Society of Anesthesiology physical status I and II and we reviewed their anesthetic charts. The P(a-ET)CO2 with respect to the BKI divided patients into two groups: 16 to 2 values between the two groups. Results: In patients aged 16 to 2 was 2.2 ± 3.1 mmHg at BKI 2 was 3.2 ± 4.1 mmHg at BKI 2 tends to increase in obese patients during general anesthesia with increasing BKI in patients aged 16 to < 65 years old.展开更多
The purpose of this study was to investigate the effect of nonadrenergic agents on cardiopulmonary resuscitation (CPR) and end-tidal CO2(ETCO2)during CPR in a rodent model. Our results suggested that: 1) coronary perf...The purpose of this study was to investigate the effect of nonadrenergic agents on cardiopulmonary resuscitation (CPR) and end-tidal CO2(ETCO2)during CPR in a rodent model. Our results suggested that: 1) coronary perfusion pressure (CPP) after drugs infusion was increased significantly by methoxamine, arginine vasopresin (AVP) and angiotension- Ⅱ(ANG- Ⅱ), but not by endothelin-1 (ET-1): 2) ETCO2 prior to defibrillation was decreased significantly by a pure a1 adrenergic agents,methoxamine and were increased significantly by non-adrenergic agents, ANG-Ⅱ and ET-1 during rodent CPR;3) a significant positive correlation between ETCO2 and CPP was observed in AVP group, suggesting that AVP have little effect on pulmonary circulation; and 4) methoxamine, AVP and ANG-Ⅱ have similar effect on resuscitability during rodent CPR.展开更多
The mixed venous-to-arterial carbon dioxide(CO_2)tension difference[P(v-a) CO_2]is the difference between carbon dioxide tension(PCO_2) in mixed venous blood(sampled from a pulmonary artery catheter) and the PCO_2 in ...The mixed venous-to-arterial carbon dioxide(CO_2)tension difference[P(v-a) CO_2]is the difference between carbon dioxide tension(PCO_2) in mixed venous blood(sampled from a pulmonary artery catheter) and the PCO_2 in arterial blood.P(v-a) CO_2 depends on the cardiac output and the global CO_2 production,and on the complex relationship between PCO_2 and CO_2 content.Experimental and clinical studies support the evidence that P(v-a) CO_2 cannot serve as an indicator of tissue hypoxia,and should be regarded as an indicator of the adequacy of venous blood to wash out the total CO_2generated by the peripheral tissues.P(v-a) CO_2 can be replaced by the central venous-to-arterial CO_2 difference(△PCO_2),which is calculated from simultaneous sampling of central venous blood from a central vein catheter and arterial blood and,therefore,more easy to obtain at the bedside.Determining the △PCO_2 during the resuscitation of septic shock patients might be useful when deciding when to continue resuscitation despite a central venous oxygen saturation(SCVO_2) > 70%associated with elevated blood lactate levels.Because high blood lactate levels is not a discriminatory factor in determining the source of that stress,an increased △PCO_2(> 6 mmHg)could be used to identify patients who still remain inadequately resuscitated.Monitoring the △PCO_2 from the beginning of the reanimation of septic shock patients might be a valuable means to evaluate the adequacy of cardiac output in tissue perfusion and,thus,guiding the therapy.In this respect,it can aid to titrate inotropes to adjust oxygen delivery to CO_2 production,or to choose between hemoglobin correction or fluid/inotrope infusion in patients with a too low ScvO_2 related to metabolic demand.The combination of P(v-a) CO_2 or △PCO_2 with oxygen-derived parameters through the calculation of the P(v-a) CO_2 or △PCO_2/arteriovenous oxygen content difference ratio can detect the presence of global anaerobic metabolism.展开更多
BACKGROUND Endoscopic thyroidectomy has obvious advantages over conventional surgical techniques in terms of postoperative cosmetic outcome.Although the incidence of carbon dioxide embolism(CDE)during endoscopic thyro...BACKGROUND Endoscopic thyroidectomy has obvious advantages over conventional surgical techniques in terms of postoperative cosmetic outcome.Although the incidence of carbon dioxide embolism(CDE)during endoscopic thyroidectomy is very low,it is potentially fatal.The clinical manifestations of CDE vary,and more attention should be paid to this disorder.CASE SUMMARY A 27-year-old man was scheduled for thyroidectomy by the transoral vestibular approach.The patient had no other diseases or surgical history.During the operation,he developed a CDE following inadvertent injury of the anterior jugular vein.The clinical manifestation in this patient was a transient sharp rise in end-tidal carbon dioxide,and his remaining vital signs were stable.In addition,loud coarse systolic and diastolic murmurs were heard over the precordium.The patient was discharged on day 4 after surgery without complications.CONCLUSION A transient sharp rise in end-tidal carbon dioxide is considered a helpful early sign of CDE during endoscopic thyroidectomy.展开更多
Introduction:With the continuous progress being made in medicine and surgery,increasingly more advanced technology and monitoring equipment are being used in anesthesia,end-tidal carbon dioxide(PETCO_(2))monitoring re...Introduction:With the continuous progress being made in medicine and surgery,increasingly more advanced technology and monitoring equipment are being used in anesthesia,end-tidal carbon dioxide(PETCO_(2))monitoring revealed serious complications of cardiothoracic surgery.Case presentation:A 3-year-old boy with a body weight of 15 kg presented with a>1-month history of a heart murmur.At the moment of arterial catheter ligation,the PETCO_(2) decreased from 37 to 15 mmHg,while the blood pressure,heart rate,and airway resistance did not change significantly.After re-separation of the ligation catheter,the surgeons carefully exposed the ductus and left pulmonary artery again and ligated the ductus arteriosus.Conclusion:This case suggests that PETCO_(2) monitoring reflects the circulatory status and pulmonary blood flow.展开更多
BACKGROUND:Unsustained return of spontaneous circulation(ROSC)is a critical barrier to survival in cardiac arrest patients.This study examined whether end-tidal carbon dioxide(ETCO_(2))and pulse oximetry photoplethysm...BACKGROUND:Unsustained return of spontaneous circulation(ROSC)is a critical barrier to survival in cardiac arrest patients.This study examined whether end-tidal carbon dioxide(ETCO_(2))and pulse oximetry photoplethysmogram(POP)parameters can be used to identify unsustained ROSC.METHODS:We conducted a multicenter observational prospective cohort study of consecutive patients with cardiac arrest from 2013 to 2014.Patients’general information,ETCO_(2),and POP parameters were collected and statistically analyzed.RESULTS:The included 105 ROSC episodes(from 80 cardiac arrest patients)comprised 51 sustained ROSC episodes and 54 unsustained ROSC episodes.The 24-hour survival rate was significantly higher in the sustained ROSC group than in the unsustained ROSC group(29.2%vs.9.4%,P<0.05).The logistic regression analysis showed that the difference between after and before ROSC in ETCO_(2)(ΔETCO_(2))and the difference between after and before ROCS in area under the curve of POP(ΔAUCp)were independently associated with sustained ROSC(odds ratio[OR]=0.931,95%confi dence interval[95%CI]0.881-0.984,P=0.011 and OR=0.998,95%CI 0.997-0.999,P<0.001).The area under the receiver operating characteristic curve ofΔETCO_(2),ΔAUCp,and the combination of both to predict unsustained ROSC were 0.752(95%CI 0.660-0.844),0.883(95%CI 0.818-0.948),and 0.902(95%CI 0.842-0.962),respectively.CONCLUSION:Patients with unsustained ROSC have a poor prognosis.The combination ofΔETCO_(2) andΔAUCp showed signifi cant predictive value for unsustained ROSC.展开更多
In order to investigate the effect of organic liquid molecular structure and the intermolecular force operating with CO2 molecules and organic liquid molecules on interfacial tension(IFT) between CO2 and organic liqui...In order to investigate the effect of organic liquid molecular structure and the intermolecular force operating with CO2 molecules and organic liquid molecules on interfacial tension(IFT) between CO2 and organic liquid at the first contact, the interfacial tension between CO2 and hexane, octane, ethanol and cyclohexane at different temperatures and pressures is measured by using the pendant drop method and the axisymmetric drop shape analysis(ADSA). The results show that the interfacial tension between CO2 and organic liquids is affected by the polarity and the structure of the organic liquid molecule obviously. The intermolecular force operating within CO2 molecules or organic liquid, and that between CO2 and organic liquids molecules play a dominate role on the interfacial tension between CO2 and the organic liquids.展开更多
基金supported in part by grants from the National Natural Science Foundation of China(30700303)the National Clinical Key Subject Construction Project
文摘BACKGROUND: Partial pressure of end-tidal carbon dioxide(PETCO2) has been used to monitor the effectiveness of precordial compression(PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation(CPR). This study was to investigate changes of PETCO2 during CPR in rats with ventricular fi brillation(VF) versus asphyxial cardiac arrest.METHODS: Sixty-two male Sprague-Dawley(SD) rats were randomly divided into an asphyxial group(n=32) and a VF group(n=30). PETCO2 was measured during CPR from a 6-minute period of VF or asphyxial cardiac arrest.RESULTS: The initial values of PETCO2 immediately after PC in the VF group were signifi cantly lower than those in the asphyxial group(12.8±4.87 mmHg vs. 49.2±8.13 mmHg, P=0.000). In the VF group, the values of PETCO2 after 6 minutes of PC were significantly higher in rats with return of spontaneous circulation(ROSC), compared with those in rats without ROSC(16.5±3.07 mmHg vs. 13.2±2.62 mmHg, P=0.004). In the asphyxial group, the values of PETCO2 after 2 minutes of PC in rats with ROSC were signifi cantly higher than those in rats without ROSC(20.8±3.24 mmHg vs. 13.9±1.50 mmHg, P=0.000). Receiver operator characteristic(ROC) curves of PETCO2 showed signifi cant sensitivity and specifi city for predicting ROSC in VF versus asphyxial cardiac arrest.CONCLUSIONS: The initial values of PETCO2 immediately after CPR may be helpful in differentiating the causes of cardiac arrest. Changes of PETCO2 during CPR can predict outcomes of CPR.
文摘Background: We investigated the differences between partial pressure of arterial carbon dioxide and end-tidal carbon dioxide (P(a-ET)CO2) with respect to the Broca-Katsura index (BKI), which is an obesity index, in obese patients during general anesthesia. Materials and Methods: From January 2003 to December 2013, we studied 601 patients aged 16 years old or over undergoing general anesthesia. Patients had American Society of Anesthesiology physical status I and II and we reviewed their anesthetic charts. The P(a-ET)CO2 with respect to the BKI divided patients into two groups: 16 to 2 values between the two groups. Results: In patients aged 16 to 2 was 2.2 ± 3.1 mmHg at BKI 2 was 3.2 ± 4.1 mmHg at BKI 2 tends to increase in obese patients during general anesthesia with increasing BKI in patients aged 16 to < 65 years old.
文摘The purpose of this study was to investigate the effect of nonadrenergic agents on cardiopulmonary resuscitation (CPR) and end-tidal CO2(ETCO2)during CPR in a rodent model. Our results suggested that: 1) coronary perfusion pressure (CPP) after drugs infusion was increased significantly by methoxamine, arginine vasopresin (AVP) and angiotension- Ⅱ(ANG- Ⅱ), but not by endothelin-1 (ET-1): 2) ETCO2 prior to defibrillation was decreased significantly by a pure a1 adrenergic agents,methoxamine and were increased significantly by non-adrenergic agents, ANG-Ⅱ and ET-1 during rodent CPR;3) a significant positive correlation between ETCO2 and CPP was observed in AVP group, suggesting that AVP have little effect on pulmonary circulation; and 4) methoxamine, AVP and ANG-Ⅱ have similar effect on resuscitability during rodent CPR.
文摘The mixed venous-to-arterial carbon dioxide(CO_2)tension difference[P(v-a) CO_2]is the difference between carbon dioxide tension(PCO_2) in mixed venous blood(sampled from a pulmonary artery catheter) and the PCO_2 in arterial blood.P(v-a) CO_2 depends on the cardiac output and the global CO_2 production,and on the complex relationship between PCO_2 and CO_2 content.Experimental and clinical studies support the evidence that P(v-a) CO_2 cannot serve as an indicator of tissue hypoxia,and should be regarded as an indicator of the adequacy of venous blood to wash out the total CO_2generated by the peripheral tissues.P(v-a) CO_2 can be replaced by the central venous-to-arterial CO_2 difference(△PCO_2),which is calculated from simultaneous sampling of central venous blood from a central vein catheter and arterial blood and,therefore,more easy to obtain at the bedside.Determining the △PCO_2 during the resuscitation of septic shock patients might be useful when deciding when to continue resuscitation despite a central venous oxygen saturation(SCVO_2) > 70%associated with elevated blood lactate levels.Because high blood lactate levels is not a discriminatory factor in determining the source of that stress,an increased △PCO_2(> 6 mmHg)could be used to identify patients who still remain inadequately resuscitated.Monitoring the △PCO_2 from the beginning of the reanimation of septic shock patients might be a valuable means to evaluate the adequacy of cardiac output in tissue perfusion and,thus,guiding the therapy.In this respect,it can aid to titrate inotropes to adjust oxygen delivery to CO_2 production,or to choose between hemoglobin correction or fluid/inotrope infusion in patients with a too low ScvO_2 related to metabolic demand.The combination of P(v-a) CO_2 or △PCO_2 with oxygen-derived parameters through the calculation of the P(v-a) CO_2 or △PCO_2/arteriovenous oxygen content difference ratio can detect the presence of global anaerobic metabolism.
基金Science and Technology Bureau of Shapingba District,Chongqing,China,No.JCD202041and Science and Technology Bureau of Chongqing,China,No.CSTC2019JXJL130029.
文摘BACKGROUND Endoscopic thyroidectomy has obvious advantages over conventional surgical techniques in terms of postoperative cosmetic outcome.Although the incidence of carbon dioxide embolism(CDE)during endoscopic thyroidectomy is very low,it is potentially fatal.The clinical manifestations of CDE vary,and more attention should be paid to this disorder.CASE SUMMARY A 27-year-old man was scheduled for thyroidectomy by the transoral vestibular approach.The patient had no other diseases or surgical history.During the operation,he developed a CDE following inadvertent injury of the anterior jugular vein.The clinical manifestation in this patient was a transient sharp rise in end-tidal carbon dioxide,and his remaining vital signs were stable.In addition,loud coarse systolic and diastolic murmurs were heard over the precordium.The patient was discharged on day 4 after surgery without complications.CONCLUSION A transient sharp rise in end-tidal carbon dioxide is considered a helpful early sign of CDE during endoscopic thyroidectomy.
文摘Introduction:With the continuous progress being made in medicine and surgery,increasingly more advanced technology and monitoring equipment are being used in anesthesia,end-tidal carbon dioxide(PETCO_(2))monitoring revealed serious complications of cardiothoracic surgery.Case presentation:A 3-year-old boy with a body weight of 15 kg presented with a>1-month history of a heart murmur.At the moment of arterial catheter ligation,the PETCO_(2) decreased from 37 to 15 mmHg,while the blood pressure,heart rate,and airway resistance did not change significantly.After re-separation of the ligation catheter,the surgeons carefully exposed the ductus and left pulmonary artery again and ligated the ductus arteriosus.Conclusion:This case suggests that PETCO_(2) monitoring reflects the circulatory status and pulmonary blood flow.
基金supported by National Natural Science Foundation of China General Program (82172179)Mathematics Tianyuan Fund (12126604)Central High-level Hospital Clinical Research Project (2022-PUMCH-B-110)
文摘BACKGROUND:Unsustained return of spontaneous circulation(ROSC)is a critical barrier to survival in cardiac arrest patients.This study examined whether end-tidal carbon dioxide(ETCO_(2))and pulse oximetry photoplethysmogram(POP)parameters can be used to identify unsustained ROSC.METHODS:We conducted a multicenter observational prospective cohort study of consecutive patients with cardiac arrest from 2013 to 2014.Patients’general information,ETCO_(2),and POP parameters were collected and statistically analyzed.RESULTS:The included 105 ROSC episodes(from 80 cardiac arrest patients)comprised 51 sustained ROSC episodes and 54 unsustained ROSC episodes.The 24-hour survival rate was significantly higher in the sustained ROSC group than in the unsustained ROSC group(29.2%vs.9.4%,P<0.05).The logistic regression analysis showed that the difference between after and before ROSC in ETCO_(2)(ΔETCO_(2))and the difference between after and before ROCS in area under the curve of POP(ΔAUCp)were independently associated with sustained ROSC(odds ratio[OR]=0.931,95%confi dence interval[95%CI]0.881-0.984,P=0.011 and OR=0.998,95%CI 0.997-0.999,P<0.001).The area under the receiver operating characteristic curve ofΔETCO_(2),ΔAUCp,and the combination of both to predict unsustained ROSC were 0.752(95%CI 0.660-0.844),0.883(95%CI 0.818-0.948),and 0.902(95%CI 0.842-0.962),respectively.CONCLUSION:Patients with unsustained ROSC have a poor prognosis.The combination ofΔETCO_(2) andΔAUCp showed signifi cant predictive value for unsustained ROSC.
基金Supported by the National Basic Research Program of China(2011CB707305)the National Key Technologies R & D Program(2012BAC24B00)+2 种基金National Nature Science Foundation of China(51304222)the CNPC Innovation Foundation(2013D-5006-0204)the Science Foundation of China University of Petroleum(YJRC-2013-20)
文摘In order to investigate the effect of organic liquid molecular structure and the intermolecular force operating with CO2 molecules and organic liquid molecules on interfacial tension(IFT) between CO2 and organic liquid at the first contact, the interfacial tension between CO2 and hexane, octane, ethanol and cyclohexane at different temperatures and pressures is measured by using the pendant drop method and the axisymmetric drop shape analysis(ADSA). The results show that the interfacial tension between CO2 and organic liquids is affected by the polarity and the structure of the organic liquid molecule obviously. The intermolecular force operating within CO2 molecules or organic liquid, and that between CO2 and organic liquids molecules play a dominate role on the interfacial tension between CO2 and the organic liquids.
