Comparative induction of controlled circulation by magnesium and remifentanil in spine surgery

Table 2 Perioperative variables

	MGS	REM	P value
	n = 20	n = 19
Duration of surgery (min)	168 ± 54	162 ± 42	0.32
Lowest recorded MAP (mmHg)	52 ± 13	55 ± 15	0.72
Intravenous fluids (L)	3.6 ± 0.9	3.3 ± 1.02	0.39
Urine output (mL)	959 ± 368	1043 ± 508	0.56
Intraoperative blood loss (mL)	650 ± 336	681 ± 313	0.77
Transfusion frequency (%)	3 (15%)	5 (26%)	0.21
PRBC transfused (units)	1.75 ± 0.46	1.50 ± 0.54	0.33
Preop. serum magnesium (mEq/L)	2.16 ± 0.21	2.18 ± 0.19	0.76

MGS: Magnesium sulfate; REM: Remifentanil; MAP: Mean arterial pressure; PRBC: Packed red blood cells; Preop.: Preoperative.