PT  - JOURNAL ARTICLE
AU  - Susanna Desole
AU  - Susann Czekay
AU  - Tom Bollmann
AU  - Katharina Lau
AU  - Ralf Ewert
AU  - Christian M. Kaehler
TI  - The indirect Fick method is an unfeasible method for hemodynamic assessment in pulmonary arterial hypertension patients
DP  - 2011 Sep 01
TA  - European Respiratory Journal
PG  - p2310
VI  - 38
IP  - Suppl 55
4099  - http://erj.ersjournals.com/content/38/Suppl_55/p2310.short
4100  - http://erj.ersjournals.com/content/38/Suppl_55/p2310.full
SO  - Eur Respir J2011 Sep 01; 38
AB  - The indirect Fick method (FickInd) is often used for the hemodynamic evaluation in pulmonary arterial hypertension (PAH). As the FickInd calculates the cardiac output (CO) assuming physiological VO2 values, this method might be unfeasible for patients with pulmonary vascular diseases. We evaluated the suitability of hemodynamic data obtained by FickInd in PAH.Right heart catheterization was performed in 43 PAH patients (age 61±13 yrs) and 9 controls. 61% of patients suffered from idiopathic PAH, 30% from PAH associated with connective tissue diseases, the remaining 9% from other forms of PAH. Hemodynamic results obtained by FickInd were compared to data from the thermodilution (TD) method.Patients and controls did not differ in age and BSA. No significant difference between heart rates during the different techniques was detected in either group. Mean CO determined by FickInd (COFick) was 4.3±1.8 and 4.7±1.2 L/min in PAH patients and controls, respectively. In PAH patients CO by TD method (COThermo) was consistently higher than COFick (4.9±2.0 L/min) showing a significant difference (Wilcoxon; p<0.001). In controls COThermo was 5.4±1.4 L/min (not significant to COFick). Agreement analysis of COThermo with COFick revealed a comparable bias between methods in both groups (0.5±1.1 L/min in patients; 0.65±0.82 L/min in controls) with wider limits of agreement for the patient cohort (-1.6 to 2.6 L/min versus -1.0 to 2.3 L/min in controls).Determination of CO by the FickInd cannot be used in PAH patients as this method consequently underestimates CO. It can be suggested that the estimated VO2 values in use for the calculation of the CO are invalid for PAH patients.