Fig. 3. The predicted effect of patient hematocrit on the carboxyhemoglobin (COHb) saturation in a 70-kg patient receiving an anesthetic at 1,000 ml/min fresh gas flow, tidal volume of 15 ml/kg, respiratory rate of 10 breaths/min, and fraction of inspired oxygen of 40%. Solid lines 1, 2, 3, and 4 represent hematocrits of 18, 30, 42, and 60%, respectively, with a 24-h barium hydroxide lime desiccation time and 7.5% end-tidal desflurane. Dashed lines 5, 6, 7, and 8 represent hematocrits of 18, 30, 42, and 60%, respectively, with a 66-h barium hydroxide lime desiccation time and 1.5% end-tidal isoflurane.