The Effect of Lung Disease in the Arterial to End-Tidal Carbon Dioxide Tension Difference / 대한마취과학회지

BACKGROUND: The purpose of this study was to evaluate the effects of lung disease on the difference between arterial and end-tidal carbon dioxide tension by placing patients from the supine to the lateral decubitus position and by the changes from two lung ventilation (TLV) to one lung ventilation (OLV) during thoracic surgery. METHOD: Fifteen patients who had no parenchymal lung disease were selected for control group and 15 patients who had parenchymal lung disease on non-dependent lung were selected for disease group. All patients had been intubated with double lumen endobronchial tubes and respiration was controlled with a rate of 14-15 breaths per minute and tidal volume 8 ml/kg. End-tidal and arterial carbon dioxide tension were measured at three different measurement periods (supine plus TLV, lateral decubitus plus TLV, lateral decubitus plus OLV). RESULTS: The arterial to end-tidal carbon dioxide tension difference was more increased in disease group than control group. But there was no significant difference in arterial to end-tidal carbon dioxide tension with position change, ventilation method change in each groups. CONCLUSION: We conclude that the arterial to end-tidal carbon dioxide tension difference is increased in lung disease, but it does not changed with position and ventilation method change.

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.

The Relationship between End Tidal and Arterial Carbon Dioxide Tension during Endobronchial Anesthesia / 대한마취과학회지

The purpose of this study is to evaulate the relationship between end-tidal PCO2(PetCO2) and arterial PCO2(PaCO2) by placing patients from the supine to the lateraI decubitus position and by the changes from two lung ventilation(TLV) to one lung ventilation(OLV) during noncardiac thoracic surgery in 20 patients. All patients had been intubated with double-lumen endobronchial tubes and respirations were controlled with a rate of 14- l7 breaths per minute and tidal volume of 8 ml/kg by an anesthetic ventilator. End tidal PCO2 and arterial PCO2 were measured at three different measurement points(supine plus TLV, lateral decubitus plus TLV, and lateral decubitus plus OLV). End tidal PCO was obtained by mainstream infrared analysis, and arterial blood samples for arterial PCO2 were taken from the radial artery simultaneously. The results were as follows: l) The mean difference between arterial and end tidal carbon dioxide tension(Pa-etCO2) was 7.5+/-2.9mmHg at the supine position, TLV(r=0.76, P<0.01). 2) The mean Pa-etCO2 was 6.2+/-3.1 mmHg at the lateral decubitus position, TLV(r =0.68, P < O.ol ). 3) The mean Pa-etCO2 was 7.1+/-2.5 mmHg at the lateral decubitus position, OLV(r=0.85, P< 0.01). 4) The changes in Pa-etCO2 were very slight during thoracotomy and endobronchial anesthesia, these were of negligible clinical importance. We conclude that measurement of PetCO2 is reliable as a guideline of ventilation during endobronchial anesthesia.

End - tidal Carbon Dioxide Measurements in the Pediatric Patients : A Comparison of End - tidal PCO2 Sampled from the Proximal and Distal Ends of Pediatric Uncuffed Tracheal Tube / 대한마취과학회지

To determine the accuracy of end-tidal PCO2(PetCO2) measurement analysed with Ohmeda 5210 capnometer in the pediatric patients whose jung were ventilated with Ohio infant Circle Absorber and Ohio Ventilatior 7200, we compared PetCO2, measurements sampled from the proximal(PetCO2-p) and distal(PetCO2-d) ends of the tracheal tube to arterial PCO2(PaCO2) in 22 healthy pediatric patients between 6.8 to 18.5kg. The results were as follow: 1) Proximal PetCO2 and distal PetCO2 correlated with PaCO2(r=0.76%, SEE=2.79, r=0.70:SEE=3.01, respectively)(p<0.05). 2)Arterial to end-tidal PCO2 difference(delta(a-et)PCO2) was significantyly greater with distal(3.53+/-4.68 mmhg) than proximal(0.35+/-2.72 mmhg) sampling(p<0.05). 3) In subgroup of patients whose proximal to distal concentration of nitrous oxide difference was more than 2%, the delta(a-et)PCO2 using distal sampling(7.90+/-5.15 mmhg) was also significantly greater then it was using proximal sampling(-1.73+/-2.39 mmhg)(p<0.05).. We conclude that distal estimates of PetCO2-P can not provide accepatbale estimate of PaCO2 in healthy pediatric patients who are intubated with pediatric uncuffed tracheal tube.

Comparison of the End-Tidal PCO2 Measurements Sampled at the Distal and Proximal Ends of the Endotracheal Tube in Adults / 대한마취과학회지

To determine whether the site of gas sampling affects end-tidal gas measurements in adult patients during anesthesia, end-tidal pCO2(PetCO2) was measuredcontinuously from the distal and proximal ends of the endotracheal tube(SHERIDAN) in 33 adults ventilated with Drager anesthesia ventilator. These data were compared with simultaneous arterial PCO2 (PaCO2) measurements. The study was commenced after each patients was ventilated no less than 15 minutes at the desired ventilator settings. Gas was continuously aspirated at 230 ml/min. for measurement of the PetCO2 using SARA Cap.A.G,Capnometer'sampled from the distal and proximal ends of the endotracheal tube for 3-minutes of each sampling port, alternativiely measured at 5 minutes interval. And each measurement was repeated twice and calculated mean values. The results were as follows: The mean PetCO2 sampling from the distal end was 31.6+/-2.4 mmHg. and the proximal end was 31.0+/-2.3mmHg. The difference between two results was statistically not significant(p> 0.05). The correlation coefficients of PetCO2 vslues for the distal end and the proximal end samplings to the PaCO2 values were r =0.48 and r=0.45 respectively, and statistically significant(p< 0.05) We concluded that the measured PetCO2 sampled from the distal end of the ETCO cuffed endotracheal tube' does not show any statistically significance to the proximal one. However, distally sampled PetCO2 measurements were more approximate PaCO2 measurements than proximally sampled one.