Table 2.

Results from short-term experiments

	Placebo		Nalbuphine			Placebo		Nalbuphine
			1 mg/kg/h infusion		Placebo vs Nalbuphine 1 mg/kg/h			5 mg/kg/h infusion		Placebo vs Nalbuphine 5 mg/kg/h	Nalbuphine 1 mg/kg/h vs 5 mg/kg/h
	(n = 6)		(n = 6)			(n = 6)		(n = 6)
	mean	±SD	mean	±SD	p value	mean	±SD	mean	±SD	p value	p value
Respiratory parameters
Respiration rate [1/min]	55	7.7	45	4.1	0.021	51	9.1	41	4.7	0.035	0.10
pO2 [kPa]	8.85	1.39	7.86	2.41	0.41	9.42	2.17	6.81	0.89	0.022	0.19
SaO2 [%]	91	4.7	84	8.1	0.09	90	8.2	78	6.6	0.017	0.024
pCO2 [kPa]	6.13	0.68	7.72	1.28	0.023	6.60	1.11	8.49	0.95	0.010	0.07
HCO3 [mmol/l]	27.0	3.0	29.7	3.6	0.19	27.2	1.9	28.5	3.5	0.42	0.30
pH	7.38	0.04	7.32	0.03	0.018	7.35	0.06	7.26	0.03	0.007	0.004
Base excess [mmol/l]	1.9	3.4	3.6	3.3	0.40	1.6	1.6	1.5	3.7	0.94	0.08
Hemodynamic parameters
Heart rate (1/min)	409	23.5	336	30.2	<0.001	408	30.4	332	40.3	0.004	0.58
Mean arterial pressure (mmHg)	96	14.7	78	10.3	0.037	89	13.1	70	6.4	0.010	0.09
Lactate [mmol/l]	1.0	0.3	0.9	0.2	0.22	1.1	0.3	0.9	0.1	0.20	0.71
Haematocit [%]	36	5.9	37	3.6	0.82	34	3.1	33	3.5	0.45	0.031

Legend: Data are shown as mean ± standard deviation (SD). All data were obtained while animals were under isoflurane anesthesia. Blood sampling was performed twice in each animal (Fig. 1). Nalbuphine 1 vs 5 mg/kg/h was compared using a paired t test. Nalbuphine vs placebo was compared using an unpaired t-test, as these two groups were independent. italic values indicate significance p < 0.05