Table 1.

Serial blood gas analyses prior and after administration of methylene blue (1 mg/kg IV) in a dog with hereditary methemoglobinemia

Day	1	2	3	3	4	4	5
Time	13:32	16.45a	11:25	17:50	9:36	18:58	9:51
Sample	Arterial	Arterial	Arterial	Venous	Venous	Venous	Venous	Reference interval
pH	7.401	7.425	7.457	7.44	7.425	7.412	7.397	7.36–7.44 (arterial)
								7.34–7.43 (venous)
pCO2	35.3	32	32.4	38.2	33.4	35.1	35.9	27.1–38.7 mmHg (arterial)
								29.7–46 mmHg (venous)
pO2	85.8	93.8	101	46.7	61.7	53.9	56.4	82.7–120 mmHg (arterial)
								31.6–63.9 mmHg (venous)
HCO3	21.4	20.6	22.6	25.6	21.5	21.9	21.6	17.2–23 mEq/L (arterial)
								18.7–25.6 mEq/L (venous)
HCT	48.1	52.3	51.6	50.7	47.6	49.6	47.3
MetHb	27.2	3.6	5.8	5.7	8.8	12	13.9	0.0–1.0%
FiO2(%)	21	21	21	21	21	21	21

^a1 hour postintravenous MB administration.