Direct, remote and combined ischemic conditioning in liver surgery

Table 1 Randomized controlled trials on remote ischemic preconditioning in liver surgery

Ref.	Intervention (patients, n)	Ischemia-reperfusion	Place of ischemia	Cirrhosis, n	Pringle maneuver	Primary endpoint
Kanoria et al[49], 2017	RIPC (8)	2 × 10 + 10	Lower limb	-	No	Feasibility, safety
	Control (8)	-	-	-
Rakić et al[50], 2018	RIPC (20)	3 × 5 + 5	Upper limb	-	Yes	Liver function tests
	IPC (20)	15 + 10	Portal triad	-
	Control (20)	-	-	-
Teo et al[51], 2020	RIPC (24)	4 × 5 + 5	Upper limb	13	Selectively	Serum ALT
	Control (26)	-	-	19
Liu et al[52], 2019	RIPC (69)	3 × 5 + 5	Upper limb	56	Yes (in 20 min cycles)	Peak level of total bilirubin
	Control (67)	-	-	51
Wu et al[53], 2020	RIPC (34)	3 × 5 + 5	Upper limb	23	Yes	Serum ALT and AST
	IPC (32)	10 + 10	Portal triad	26
	Control (39)	-	-	25

ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; IPC: Ischemic preconditioning; RIPC: Remote ischemic preconditioning.