Study the effect of adding Magnesium sulfate to TAP block in analgesia after laparoscopic cholecystectomy.

After approval of local ethical committee, consent will be obtained from 90 patients scheduled for laparoscopic cholecystectomy in GEC center, Mansoura University, Egypt. Patients will be of either ASA I and II, with Age ranging from 18-40 years, and BMI less than 35. Patients will be randomized into 3 groups (using closed envelope technique in blocks of 18); Controlled group (C group), Bupivacaine group (B group), Bupivacaine Magnesium group (M group).

Anesthesia induction will be the same in the three groups (Propofol 1-1.5mglkg, Fentanyl 1 mic/kg, Atracrium 0.5 mg/kg) then Sevoflorane inhalational anesthesia for maintainace in 0.4 oxygen/air mixtures.

In both M group and B group, preemptive US guided Subcostal TAP block (Toshiba Xario, Japan) was performed on both sides using 20 ml volume (0.25 Bupivacaine in B group or 0.25 Bupivacaine plus 0.5 gm MgSo4 in M group). Surgical sterilization will be started 5 minutes after the block and surgery started5 minutes later. Hemodynamic data (HR, MAP) will be collected immediately after induction, at start of surgery, and each 10 minutes later.

At the end of surgery, and after closure of surgical ports, anesthesia was terminated and extubation done when patients fulfilled the required criteria. Postoperative hemodynamic data (HR, MAP), VAS, and PONV will berecorded at 0, 1, 2, 6, 12, 24 hours after surgery, Ramsay sedation was recorded at 0, 1, 2, 6 hours postoperatively. Boluses of Morphine (0.02 mg/kg) will be given whenever VAS ≥4.

Inclusion Criteria:

• ASA I, II for lap cholecystectomy

Exclusion Criteria:

• ASA III, IV