1 3 2 4 6 7 10 11 1 12 15 16 17 Fasting before operation and induction of anesthesia leads to relative hypovolemia and the goal is therefore to compensate this before PP is started. In this study, we compared three different fluid regimes in LDN patients, in which the effect of pre-hydration together with a bolus of colloids given just before induction of anesthesia and a second one just before inflation of PP on hemodynamics was of special interest. Methods N 1 Table 1. Infusion protocols used in the three groups Group n a b c d e ml HES/ IBW total 1 7 3 13 6 6  12 2 7 2 13 6  3 × 2 12 3 7  16   3 × 4 12 IBW = ideal body weight  n a b c d e HES = 6% HES 130/0.4 Induction of anesthesia was performed with propofol (2 mg/kg) after a bolus of sufentanil (0.3 μg/kg). Muscle relaxation was achieved with rocuronium (0.8 mg/kg) and monitored by train-of-four (TOF) guard, a bolus of rocuronium (0.3 mg/kg) was given for three or more twitches. Anesthesia was maintained with propofol by continuous infusion (4–11 mg/kg/h), aiming at a bispectral index between 45 and 55 (BIS monitor; Aspect Medical Systems, Newton, MA, USA), and analgesia was achieved by continuous infusion of sufentanil (0.4 μg/kg/h) until nephrectomy. One hour after the start of operation 20 mg mannitol was given intravenously. ® 2 2 2 2 TM 18 20 21 22 Statistical analysis t p Results 2 1 1 1 Table 2. Demographic data on the three groups, mean (SD)  Group 1 Group 2 Group 3 Age (yrs) 56 (11) 53 (9) 55 (12) Weight (kg) 72 (9) 82 (8) 74 (7) IBW (kg) 70 (8) 78 (8) 71 (6) Male/female  2/5 4/3 3/4 Operation time (min) 237 (37) 251 (46) 226 (31) IBW = ideal body weight Fig. 1. p p p  3 p 3 Table 3. Data on hemodynamic parameters: heart rate (HR), mean arterial pressure (MAP) and left ventricular ejection time (LVETc), mean (SD). Columns correspond to seven times: before anesthesia (preop); after induction of anesthesia, supine position (supine); full lateral position (lateral); and mean measurement for the first, second, third and fourth 30 minutes after installation of pneumoperitoneum (PP30, PP60, PP90 and PP120, respectively)  Preop Supine Lateral PP30 PP60 PP90 PP120 HR   Group 1 65 (6) 65 (13) 63 (20) 60 (9) 61 (8) 60 (10) 61 (9)   Group 2 63 (11) 60 (9) 61 (14) 62 (11) 61 (9) 63 (6) 63 (8)   Group 3 (control)  73 (9) 69 (14) 61 (6) 65 (10) 63 (6) 60 (7) 61 (6) MAP   Group 1 102 (11) # 81 (19)* 93 (14) 96 (15) 94 (17) 98 (20)   Group 2 102 (14) 73 (10)* 81 (15)* 107 (10) 107 (18) 104 (8) 102 (12)   Group 3 (control)  105 (12) 70 (11)* 79 (7)* 103 (9) 98 (11) 95 (12) 95 (15) LVETc   Group 1  # # # 345 (31) 335 (30) 336 (33)   Group 2  313 (29) 308 (39) 295 (58)° 311 (20)° 308 (27) 300 (28)   Group 3 (control)   294 (26) 284 (31) 292 (26) 307 (18) 309 (18) 311 (25) p p p p 4 4 Table 4. Creatinine clearance [mean (SD)] in the three groups at six measurement points: one day before operation; just after induction of anesthesia; at 14:30, six hours after installation of pneumoperitoneum T6; two days after operation; one month after operation; and one year after operation  Group 1 Group 2 Group 3 (control) CrCl preop (ml/min) 89 (19) 101 (25) 102 (34) CrCl after induction (ml/min) 104 (18) 109 (20) 96 (31) CrCl after the operation (ml/min) 87 (17) 94 (14) 73 (23)ª CrCl D2 (ml/min) 63 (10)* 65 (11)* 64 (19)* CrCl after 1 month (ml/min) 63 (12)* 67 (11)* 63 (24)* CrCl after 1 year (ml/min) 71 (13) 71 (13)* 66 (25)* p p Discussion This study showed that during LDN preoperative hydration together with a bolus of colloid given before induction of anesthesia and before installation of PP resulted in higher SV and higher urine output compared to a fluid regimen with only an intraoperative aggressive fluid infusion. The second group, which received no bolus of colloid before PP in contrast to group 1, showed a significant reduction in SV after installation of PP. In the control group, LVETc and urine output at the moment of kidney extraction showed significantly lower values compared to both pre-hydration groups. CrCl values six hours after the start of the operation was significantly reduced in the control group compared to preoperative values but not in the two pre-hydrated groups; this difference was reduced two days postoperatively. 4 23 11 24 25 1 26 27 28 29 30 31 TM 18 32 20 33 2 Some other limitations of this study should be noted. In only four patients a MAG3 scan was performed, which provides the distribution of the function from the two kidneys of the donor. In the four measured patients the harvested kidney contributed 43–48% of the total kidney function, these four patients were divided over all three study groups. However because we do not have the data on the other patients, this could have biased our data on postoperative CrCl. Prehydration of the donor patients conform our protocol, started the night before operation, which contradicts fast-track surgery where kidney donor patients are admitted to hospital on the day of surgery. Also these patients can receive adequate pre-hydration, but further research should be done. 34