The Effect of Pneumoperitoneum and Trendelenburg position on respiratory mechanics under general anesthesia during gynecological laparoscopic surgery / Монголын Анагаах Ухаан

Background@#Gynecological laparoscopic surgery requires pneumoperitoneum(PP) with CO₂ gas insufflation and Trendelenburg position. Pneumoperitoneum and Trendelenburg position may impact intraoperative respiratory mechanics in anesthetic management.The goal of this study was to evaluate the influence of Pneumoperitoneum and Trendelenburg position on respiratory mechanics and ventilation. @*Methods@#Twenty one patients scheduled for elective gynecological laparoscopy were evaluated. The patients had no preexisting lung and heart disease or pathologic lung function. Conventional general anesthesia with thiopental sodium, fentanyl, аtracrium and isoflurane was administered. The peak inspiratory pressure, plateau pressure, and end-tidal CO₂ were compared before after creation of pneumoperitoneum with an intraabdominal pressure of 15 mmH₂O, then after PP10, PP20, PP30 minutes in the 20° Trendelenburg position, and after deflation of pneumoperitoneum. The dynamic lung compliance was calculated.@*Results@#During of pneumoperitoneum, there were a significant increase in peak inspiratory pressure by 6 cmH₂O, plateau pressure by 5 cmH₂O, while dynamic lung compliance decreased by 11 ml/cmH₂O. General, the Trendelenburg position induced no significant hemodynamic and pulmonary changes.@*Conclusion@#The effects of pneumoperitoneum significantly reduced dynamic lung compliance and increased peak inspiratory and plateau pressures. The Tredelenburg position did not change these parameters. The end-tidal CO₂ significantly increased after pneumoperitoneum and CO₂ deflation.

Comparison of arterial-to-end-tidal carbon dioxide tension difference during cardiac surgery in children with cyanotic or acyanotic congenital heart disease / 临床麻醉学杂志

Objective To estimate the arterial-to-end-tidal carbon dioxide tension difference (Pa-ET CO 2 )in children with cyanotic or acyanotic congenital heart diseases;evaluate whether hyper-ventilation can reduce the tension difference or not;analyze the effect of sevofleurane on Pa-ET CO 2 . Methods One hundred and twenty patients (male 60 cases,female 60 cases,aged 1 month-6 years, ASA class Ⅱ or Ⅲ)undergoing selective cardiac surgery were randomly divided into 6 groups (n =20 each)based on right-to-left or left-to-right intracardic shunts:group A1,cyanotic with sevoflurane of 0.5 MAC;group A2,cyanotic with sevoflurane of 1.0 MAC;group B1,acyanotic with sevoflurane of 0.5 MAC;group B2,acyanotic with sevoflurane of 1.0 MAC;group C1,cyanotic with no inter-vention factors;group C2,acyanotic with no intervention factors.All the children received general an-aesthesia after placing an intravenous and arterial catheter.The value of PET CO 2 ,SpO 2 ,PaCO 2 , SaO 2 ,Hct and temperature(nasopharyngeal temperature and rectal temperature)were obtained before operation,after hyperventilation(the control groups without hyperventilation)and five minutes before surture sternum.Results The values of Pa-ET CO 2 were more than the normal one in six groups before operation.The value of Pa-ET CO 2 in group B1 was less than that in group A1,that in group B2 was less than that in group A2 and that in group C2 was less than that in group C1 before operation (P <0.01).Compared with the time point before operation,the values of Pa-ET CO 2 in groups A1,A2,B1 and B2 decreased significantly after hyperventilation (P < 0.05 or P < 0.01 ).Moreover, this reduction was more significant in groups B1 and B2.Compared with the time point before operation, the values of Pa-ET CO 2 in groups B1,B2,C2 increased significantly (P <0.01)and that in groups A1, A2,C1 decreased significantly (P <0.05)at 5 minutes before surture sternum.There was no statisti-cal difference at three different time points between group A1 and A2,B1 and B2.Conclusion The value of Pa-ET CO 2 in cyanotic children increased more significantly than that in acyanotic children.Hy-perventilation can reduce the value of Pa-ET CO 2 especially in acynanotic children with pulmonary con-gestion.The concentration (from 0.5 MAC to 1.0 MAC)of sevoflurane had little effect on the value of Pa-ET CO 2 .

Effect of PaCO2, PETCO2, P(a-ET)CO2 and Regional Cortical Blood Flow on the Prognosis of Craniotomy Patients / 대한마취과학회지

BACKGROUND: Carbon dioxide is a potent cerebral vasodilator. The change of carbon dioxide partial pressure may influence the intracranial pressure and the patients' neurological outcome. There are few reports about the influence of end-tidal CO2 (ETCO2), arterial CO2 (PaCO2) and its pressure difference P(a-ET)CO2 during a craniotomy on the Glasgow coma scale (GCS) score for evaluation of neurological status. In this study, authors tried to discover the influence of PaCO2, PETCO2, and P(a-ET)CO2 on neurological outcome. METHODS: The data of PaCO2 and PETCO2 and P(a-ET)CO2 during a craniotomy was saved. The correlations between each parameter, the GCS score and rCoBF were analyzed. To prevent a direct effect on carbon dioxide tension, blood pressure and body temperature were maintained within a normal range. At the same time, we inserted a probe of the thermal diffusion flowmetry monitor in the subdural space to monitor the regional cortical cerebral blood flow (rCoBF). All the data was saved simultaneously, at the moment of dura closure. RESULTS: There was a fair correlation between the PaCO2 and PETCO2. A low PaCO2 level correlated well with a good GCS score but, not with PETCO2. The mean P(a-ET)CO2 value was 4.4 +/- 3.1 mmHg. The high P(a-ET)CO2 level correlated well with a poor GCS score. High rCoBF correlated well with a good GCS score. However, the changes of PaCO2 and PETCO2 showed no correlations with the rCoBF. CONCLUSIONS: As a result, if we decrease the PaCO2 level by hyperventilation and increase the rCoBF level through proper management during anesthesia, we can improve the patients' neurological outcome.

Correlation between PaCO2 and PETCO2 during Laparoscopic Cholecystectomy / 대한마취과학회지

During the laparoscopic cholecystectomy, the ventilatory and hemodynamic changes could occur due to the peritoneal insufflation of CO2 as well as the position change. Various sults of the relationship between arterial and end-tidal PCO2 in different conditions have been reported. The authars studied to determine how closely end-tidal PCO2 reflects arterial PCO2 before, during, and after laparoscopic cholecystectomy. Peak inspiratory airway pressures, arterial blood pressures and heart rates were also measured simultaneously. Peritoneal insufflation of CO2 resulted in significant increase in peak inspiratory airway pressure and arterial blood pressure, but there were no significant changes in heart rates. Arterial and end-tidal PCO2 increased during laproscopy and, although there was no statistical significance in P(a-ET)CO2, P(a-ET)CO2 increased during laparoscopy and retumed to perinsufflation level after deflation of CO2. There was positive correlation between arterial and end-tidal PCO2 before CO2 insufflation, 10 minutes after CO2 insufflation and 10 minutes after deflation of CO2. However there was no correlation at 30 and 50 minutes after CO2 insufflation. These results suggested that the arterial PCO2 could not reflect end-tidal PCO2 exactly, and intermittent arterial blood gas studies should be warranted during laparoscopic cholecystectomy.

End Tidal CO2 Monitoring with Salter Divided Nasal Cannula in Post-extubated Spontaneous Breathing Patients / 대한마취과학회지

For the evaluation of the correlation between the ETCO2 and the PaCO2 in post-extubated spontaneously breathing patients, we tested 30 patients in recovery room with Salter Divided Nasal Cannula, which have permanent bamer in the face piece and a dual tubing set that allows end tidal sampling from one nare and oxygen delivery to the other. When the wave form of capnogram looked regular and normal, the value of ETCO2 was recorded and the arterial blood was taken from the radial artery to analize blood gas immediately. The results were as following; 1. The mean value of PaCO2 was 42.0+/-4.8 mmHg. 2. The mean value of P(ET)CO2 was 39.3+/-5.1 mmHg. 3. The value of P(ET)CO2 acquired with Salter Divided Nasal Cannula hase close positive correlation with the values of the PaCO2. (PaCO2=0.75 x P(ET)CO2+/-12.64, r=0.79, p<0.001)