This randomized double blind clinical trial focuses on patients with Body Masse Index ≥ 40 kg/m2, undergoing scheduled surgery. Neuromuscular transmission monitoring at the adductor is performed using. Anaesthesia is induced with anaesthesic and maintained with curare. At the end of the procedure, patients with profound neuromuscular blockade receive either 1 mg/kg, 2 mg/kg or 4 mg/kg Sugammadex based on ideal body weight. A complete reversal failure is defined by a Train Of Four ratio < 0.9 within 10 min after administration of Sugammadex or if recurarization occurs within 15 min after complete reversal success.

Inclusion Criteria:

• General anaesthesia
• Neuromuscular blockade induce by rocuronium
• Body Masse Indice ≥ 40 kg/m2
• informed consent

Exclusion Criteria:

• Contraindication to rocuronium or sugammadex
• Pregnant women
• Severe renal insufficiency