Impedance cardiography accurately measures cardiac output during exercise in children with cystic fibrosis.
OBJECTIVE
After validation of impedance cardiography (ICG) in healthy children, this same device was tested in children with cystic fibrosis (CF) to validate its capability of measuring cardiac output (Q) in this population.


METHODS
Comparative study of ICG vs the indirect Fick (CO2) method.


METHODS
Tertiary care children's teaching hospital.


METHODS
Twenty-one CF children with mean FEV1 of 77 +/- 21% predicted.


METHODS
ICG results were compared with CO2 rebreathing (RB) measurements of Q with sampling of capillary blood gases at two levels of exercise (0.5 and 1.5 W/kg). ICG measurements were made each minute, and duplicate RB measurements from 6 to 8 min at each workload. Q was regressed against oxygen uptake and results by each method were compared.


RESULTS
Mean bias (QRB-QICG) was -0.09 +/- 0.94 L/min. The largest deviation of QICG from QRB was +33%, and 83% of corresponding QICG values were within +/-20% of QRB result.


CONCLUSIONS
This device gives rapid, accurate, noninvasive Q measurements in children with CF.
Pianosi
P T
PT
Department of Pediatrics and Child Health, Children's Hospital of Winnipeg, Canada.
D000293:Adolescent; D002302:Cardiac Output; D002307:Cardiography, Impedance; D002648:Child; D003550:Cystic Fibrosis / Q000503:physiopathology*; D017097:Electric Impedance; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D015203:Reproducibility of Results