Ischemic preconditioning-induced hyperperfusion correlates with hepatoprotection after liver resection

Table 1 Baseline data of study patients

Group	Age (yr)	Sex (n) M/F	Tumor (n) mal/non mal	Fibrosis (n) none/mod/sev	Steatosis (n) none/min/mod/sev
Control (A) (n = 30)	57 ± 14 (26-81)	18/12	26/4	10/15/5	8/16/5/1
IP (B) (n = 31)	55 ± 13 (28-77)	19/12	28/3	12/14/5	10/14/5/2
P-value	0.61	0.92	0.65	0.39	0.39

There were no significant differences between the control and ischemic preconditioning (IP) groups. Fibrosis: min (≤ 10%); mod (≤ 40%); liver steatosis: min (≤ 25%); mod (≤ 50%); sev (≥ 50%); mal: malignant. Examination by pathologist of non-cancerrous adjacent liver tissue; all patients included.

Table 2 No differences in the intraoperative data of the 2 groups of patients

Group	OP time (min) mean/range	PM time (min) mean/range	LR time (min) mean/range	LV resected (mL) mean/range	Segments resected (n) mean/range
Control (A) (n = 30)	260 ± 63 (170-420)	34 ± 14 (15-82)	30 ± 10 (10-50)	390 ± 303 (80-1400)	2.7 ± 1.3 (1-5)
IP (B) (n = 31)	271 ± 58 (180-420)	33 ± 12 (8-67)	31 ± 11 (15-56)	426 ± 453 (30-2000)	2.7 ± 1.1 (1-5)
P-value	0.36	0.70	0.83	0.77	0.69

OP: Operation; PM: Pringle maneuver; LR: Liver resection; LV: Liver volume.

Table 3 Flow characteristics of patients undergoing PM (control, n = 30) and IP + PM (study group, n = 31)

Group	Vessel	Baseline (mL/min)	After IP (mL/min)	15 min (mL/min)	Before abd. closure (mL/min)
Control	HA	141 ± 24	-	152 ± 29	146 ± 18
IP	HA	126 ± 19	263 ± 51	196 ± 38a	174 ± 22a
Control	PV	1023 ± 130	-	726 ± 121	757 ± 58
IP	PV	930 ± 94	920 ± 81	919 ± 75a	949 ± 62a
Total (Co)	HA + PV	1164 ± 72	-	878 ± 77	903 ± 37c
Total (IP)	HA + PV	1056 ± 53	1183 ± 64	1115 ± 49b	1123 ± 58b

There were significantly enhanced PV, HA, and total flows in IP-treated patients. PM: Pringle maneuver; HA: Hepatic artery; PV: Portal vein; abd: Abdomen; Co: Control.

^aP < 0.05,

^bP < 0.01 vs control;

^cP < 0.05 vs baseline.

Table 4 Outcome data of patients undergoing liver resection with PM (A) or with IP + PM (B)

Group	RPC (units) mean/range	ALT (U/L) mean/range	Bilirubin (mg/dL) mean/range	LF (n) transient/fatala	Biliary compl. (n) major/minor
Control (A) (n = 30)	0.90 ± 1.24 (0-5)	550 ± 650 (54-2888)	1.73 (0.40-9.83)	2 (2)	2b (4)
IP (B) (n = 31)	0.47 ± 1.31 (0-6)	247 ± 210 (45-852)	1.40 ± 1.26 (0.23-5.59)	0 (1)	1 (2)
P-value	0.014	0.04	0.69	0.04	0.04

^aDeath;

^bRequiring re-operation. Total complication rate was 14/30 (45%) in controls (A) and 6/31 (20%) in the IP group (B). One death in the study group (B) resulted from a perforated duodenal ulcer (postoperative day 21). RPC: Red packed cells; ALT: Alanine aminotransferase; LF: Liver failure; compl.: Complications.

Table 5 Factors predicting occurrence of postoperative complications by multivariate logistic regression (backward selection) of factors of importance or significance on univariate analysis

Analysis (P-value)	IP treatment	Length of PM	Resected LV	HA flow	PV flow	Liver steatosis	Liver fibrosis
Univariate	0.038	0.043	0.067	0.044	0.72	0.81	0.94
Multivariate	0.047	0.022	NS	NS	NS	NS	NS

Treatment with IP and length of the PM are the only independent predictors of complications. NS: Not significant.