In this study, the investigators will compare the effect of magnesium sulphate pretreatment on the onset and duration of intense and deep neuromuscular Block of rocuronium versus Cis-Atracurium and on the period of no response to nerve stimulation in children undergoing elective open abdominal surgeries.

Deep neuromuscular blockade is known to improve surgical conditions in procedures such as abdominal or pelvic laparoscopic surgery, laparotomy and laryngeal surgery. In addition, deep neuromuscular blockade enables a reduction in pneumoperitoneal pressure, postoperative pain and the incidence of intra-operative and postoperative adverse events. Correspondingly, the use of deep neuromuscular blockade is increasing, and for its maintenance neuromuscular monitoring is essential; the use of neostigmine may also be helpful in achieving a rapid recovery. Magnesium sulphate has gained prominence as an adjuvant drug in multimodal anesthesia and pain medicine. It has several clinical indications, including attenuation of the adrenergic response to tracheal intubation and improved peri-operative analgesia. Magnesium sulphate also enhances the action of non-depolarizing neuromuscular blocking drugs, resulting in potentiation of neuromuscular blockade (NMB).The site of magnesium potentiation of neuromuscular blocking drugs is the motor end plate, where magnesium reduces the release of prejunctional acetylcholine, thereby decreasing the muscle membrane excitability. However, limited data exist concerning the effect of magnesium sulphate on the duration of deep or intense NMB and on the period of no response to nerve stimulation. In this study, the investigators will compare the effect of magnesium sulphate pretreatment on the onset and duration of intense and deep neuromuscular Block of rocuronium versus Cis-Atracurium and on the period of no response to nerve stimulation in children undergoing elective open abdominal surgeries.

Inclusion Criteria:

1. Age group 2-12 years old
2. Both genders
3. Children who will be scheduled to undergo elective laparoscopic surgeries.
4. Patients with American Society of Anesthesiologist physical status classification of 1 or 2-

Exclusion Criteria:

1. Patients who are beyond the selected age group.
2. Patients on medications that interfered with muscle activity.
3. Allergy to medications used in this study.
4. Neuro-muscular diseases.
5. Renal or hepatic impairment.
6. Hypermagnesemia (>2.5 mmol) or hypomagnesemia (<1.7 mmol).
7. Parental refusal to participate in the study

The dose of the administered muscle relaxants will be given by an investigator not included in the study.