Pulse contour analysis and transesophageal echocardiography: a comparison of measurements of cardiac output during laparoscopic colon surgery.
BACKGROUND
Pulse wave analysis (PWA) allows cardiac output (CO) measurement after calibration by transpulmonary thermodilution. A PWA system that does not require previous calibration, the FloTrac/Vigileo (FTV), has been recently developed. We compared determinations of CO made with the FTV to simultaneous measurements using transesophageal echocardiography (TEE).


METHODS
Ten ASA I-II patients scheduled for laparoscopic colorectal surgery were studied. A radial 20-gauge cannula was inserted and connected to a hemodynamic monitor and a FTV system for PWA and determination of CO (CO(PWA)). TEE CO (CO(TEE)) was determined as previously described. Measurements were made after intubation, 5 min after establishing the lithotomy position, 5 min after establishing pneumoperitoneum, every 30 min, or each time mean arterial blood pressure decreased below basal values. Statistical analysis was made with the Bland and Altman method.


RESULTS
Eighty-eight measurements were compared. The CO(TEE) values ranged from 3.23 to 12 Lt/min (mean 6.21 +/- 1.85). Values for CO(PWA) ranged from 2.9 to 8.5 Lt/min (mean 4.84 +/- 1.14). Bias was 1.17 and limits of agreement -2.02 and 4.37. The percentage error between all CO(TEE) and CO(PWA) measurements was 40% (27%-50%) mean (range).


CONCLUSIONS
During laparoscopic colon surgery, clinically important differences were observed between CO determinations made with TEE and FTV.
Concha
Mario R
MR
Department of Anesthesiology, Escuela de Medicina, Pontificia Universidad Católica de Chile, Hospital Clínico Universidad Católica de Chile, Santiago, Chile. mconcha@med.puc.cl
Mertz
Verónica F
VF
Cortínez
Luis I
LI
González
Katya A
KA
Butte
Jean M
JM
D000368:Aged; D002302:Cardiac Output / Q000502:physiology*; D003106:Colon / Q000502:physiology / Q000601:surgery*; D017548:Echocardiography, Transesophageal / Q000379:methods* / Q000592:standards; D005260:Female; D006801:Humans; D010535:Laparoscopy / Q000379:methods* / Q000592:standards; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods* / Q000592:standards; D011674:Pulse / Q000379:methods* / Q000592:standards