Fig. 2. Bias analysis comparing cardiac output measurement results during controlled mechanical ventilation, from partial carbon dioxide rebreathing (CO^NI) and thermodilution (CO^TD) methods. (A ) Large tidal volume (V^T, 12 ml/kg) with respiratory rate (RR) of 10 breaths/min. (B ) Small tidal volume (6 ml/kg) with respiratory rate of 20 breaths/min. (C ) Small tidal volume (6 ml/kg) with respiratory rate of 10 breaths/min. Dotted lines show bias and limits of agreement between the two methods.