Table 1.

Characteristics of included trials

First author [Ref.], year	Group	Treatment	Anesthesia	Postoperative analgesia
Bhatia [17], 2014	Control (n = 20) TAP block (n = 20) Subcostal TAP block (n = 20)	Bilateral 15 ml of 0.375s% ropivacaine before extubation	Propofol/morphine/nitrous oxide/isoflurane	Acetaminophen 1 g, i.v., every 6 h, tramadol 2 mg/kg, i.v., as an initial dose and 1 mg/kg if needed
Kokulu [18], 2014	Control (n = 20) TAP block (n = 20)	Bilateral 15 ml of 0.5s% bupivacaine after induction	Midazolam/propofol/fentanyl/desflurane	No details provided
Shin [19], 2014	Control (n = 15) TAP block (n = 15) Subcostal TAP block (n = 15)	Bilateral 20 ml of 0.375s% ropivacaine after induction	Propofol/fentanyl/sevoflurane	Fentanyl 25 μg, i.v. s+ ketorolac 30 mg in the recovery room and nalbuphine 10 mg on the ward if needed
Chen [20], 2013	Control (n = 20) Subcostal TAP block (n = 20)	Bilateral 20 ml of 0.375s% ropivacaine after induction	Propofol/fentanyl/sevoflurane	Morphine 0.05 mg/kg, i.v., if needed
Petersen [21], 2012	Control (n = 37) TAP block (n = 37)	Bilateral 20 ml of 0.5s% ropivacaine after induction	Propofol/remifentanil/sufentanil	Oral acetaminophen 1 g and ibuprofen 400 mg every 6 h, morphine 2.5 mg, i.v., in the recovery room and oral ketobemidone 2.5 mg on the ward if needed
Ra [22], 2010	Control (n = 18) TAP block 0.25s% (n = 18) TAP block 0.5s% (n = 18)	Bilateral 15 ml of 0.25s% or 0.5s% l-bupivacaine after induction	Midazolam/propofol/remifentanil	Ketorolac 30 mg and fentanyl 20 μg in the recovery room if needed, ketorolac 30 mg every 8 h on the ward
El-Dawlatly [23], 2009	Control (n = 21) TAP block (n = 21)	Bilateral 15 ml of 0.5s% bupivacaine after induction	Propofol/sufentanil/sevoflurane	PCA morphine bolus 1.5 mg, i.v., with no basic infusion and 15 min lock-out time

PCA = Patient-controlled analgesia.