Noninvasive carbon dioxide monitoring during one-lung ventilation: end-tidal versus transcutaneous techniques.
OBJECTIVE
To compare transcutaneous CO(2) (TCCO(2)) and end-tidal CO(2) (ETCO(2)) monitoring during one-lung ventilation (OLV).


METHODS
Prospective study.


METHODS
Operating room of a University Hospital.


METHODS
Fifteen patients undergoing thoracic surgical procedures in whom one-lung ventilation was deemed necessary.


METHODS
TC and ETCO(2) monitors were used simultaneously in the patients and compared with arterial blood gases (ABGs) during 2-lung ventilation and OLV.


RESULTS
During 2-lung ventilation (TLV), the ET to PaCO(2) difference was 3.9 +/- 1.6 mmHg, whereas the TC to PaCO(2) difference was 2.5 +/- 0.8 mmHg (p = 0.0049). During OLV, the ET to PaCO(2) difference increased to 5.8 +/- 2.3 mmHg, whereas the TC to PaCO(2) difference was 2.7 +/- 1.4 mmHg (p = 0.0049 for ET to PaCO(2) difference during OLV v TLV and p = 0.0004 for ET to PaCO(2) gradient v TC to PaCO(2) gradient during OLV). During TLV, the difference between the ET and PaCO(2) was < or = 5 mmHg in 13 of 15 patients, whereas the difference between the TC and PaCO(2) was < or = 5 mmHg in 15 of 15 patients (p = not significant). During OLV, the difference between the ET and the PaCO(2) was < or = 5 mmHg in 6 of 15 patients, whereas the difference between the TC and PaCO(2) was < or = 5 mmHg in 14 of 15 patients (p = 0.0052, odds ratio 21.0 for ET v TC techniques and p = 0.02, odds ratio 9.75 for ET to PaCO(2) during TLV v OLV).


CONCLUSIONS
During OLV, TCCO(2) monitoring provides a more accurate estimate of PaCO(2) than ET techniques.
Tobias
Joseph D
JD
Department of Anesthesiology and Pediatrics, The University of Missouri, Columbia, MO 65212, USA. Tobiasj@health.missouri.edu
D000293:Adolescent; D000328:Adult; D001785:Blood Gas Monitoring, Transcutaneous; D002245:Carbon Dioxide / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D006801:Humans; D016343:Monitoring, Intraoperative; D011446:Prospective Studies; D012121:Respiration, Artificial; D019616:Thoracic Surgical Procedures; D013990:Tidal Volume / Q000502:physiology
D002245:Carbon Dioxide