Table 1. Demographic Characteristics of Two Groups ^a,b,c.

Patients (n = 90)	IVPCA (n = 45)	PCEA (n = 45)	P Value
Age, y	53.8 ± 11.4	49.9 ± 8.8	0.73
Weight, kg	67.96 ± 8.45	69.84 ± 7. 7	0.78
ASA			0.20
I	22 (48.8)	16 (35.5)
II	23 (51.1)	29 (64.4)
Operation time, h	3.08 ± 0.85	3.7 ± 0.79	0.001

^a Abbreviations: ASA, American Society of Anesthesiologists; IVPCA, Intravenous Patient-controlled Analgesia; PCEA, Patient Controlled Epidural Analgesia.

^b P < 0.05 is considered significant.

^c Values are presented as mean ± SD or No. (%).