Evaluation of partial carbon dioxide rebreathing cardiac output measurement during thoracic surgery.
OBJECTIVE
Noninvasive partial CO2 rebreathing (NICO; Novametrix Medical Systems, Inc, Wallingford, CT) is a relatively new alternative to thermodilution (TDCO) for measurement of cardiac output. This study compares the 2 methods during thoracic surgery and one-lung ventilation.


METHODS
A prospective, observational study.


METHODS
A tertiary hospital.


METHODS
Twelve adult patients undergoing elective thoracotomy and one-lung ventilation in the lateral decubitus position.


METHODS
Paired measurements of cardiac output were performed during (1) 2-lung ventilation in the supine position (postinduction of anesthesia), (2) 10 minutes after initiation of one-lung ventilation in the lateral decubitus position with the nondependent chest open, and (3) after 30 minutes on one-lung ventilation. An average of 3 consecutive (10 mL 20 degrees C saline) TDCO measurements made during end-expiration was compared with corresponding NICO measurements.


RESULTS
The NICO showed a tendency to underestimate cardiac output compared with TDCO at all measurement times. Overall, bias was -0.29 L/min and limits of agreement -1.69 to 1.43 L/min.


CONCLUSIONS
There was a moderate agreement between cardiac output measurements obtained with the NICO and TDCO. The present data suggest that the NICO technique may be useful during thoracic surgery.
Ng
Ju-Mei
JM
Department of Anaesthesia and Surgical Intensive Care, Singapore General Hospital, Singapore. jng1@partners.org
Chow
Mark Y
MY
Ip-Yam
Pierre C
PC
Goh
Meng-Huat
MH
Agasthian
Thirugnanam
T
D000368:Aged; D002245:Carbon Dioxide / Q000008:administration & dosage; D002302:Cardiac Output / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation / Q000379:methods*; D011446:Prospective Studies; D012119:Respiration; D012121:Respiration, Artificial / Q000379:methods*; D013815:Thermodilution / Q000379:methods*; D013908:Thoracotomy
D002245:Carbon Dioxide