Table 2. Respiratory and Hemodynamic Parameters during Controlled Mechanical Ventilation

*P < 0.05 vs.  V^T12 ml/kg, RR 10 breaths/min.

†P < 0.05 vs.  V^T6 ml/kg, RR 20 breaths/min.

CO^NI= cardiac output with carbon dioxide rebreathing; CO^TD= cardiac output with thermodilution; Paco²= arterial carbon dioxide tension; Petco²= end-tidal carbon dioxide pressure; P/F = ratio of arterial oxygen tension to inspired oxygen fraction; Q̇^S/Q̇^T= venous admixture fraction; RR = respiratory rate; V̇co²= carbon dioxide production; V^D/V^T= dead-space fraction; V̇^E= minute ventilation; V^T= tidal volume.