Comparing the effect of Propofol-Alfentanil with Ketamine-Alfentanil on endotracheal intubation without muscle relaxation

INTERVENTION: Control group: Propofol (2/5ml/kg), Alfentanil (40mic/kg) Intervention 1: Interventional group : Ketamine (2mg/kg), Alfentanil (40mic/kg). Intervention 2: Control group: Propofol (2/5ml/kg), Alfentanil (40mic/kg). Interventional group : Ketamine (2mg/kg), Alfentanil (40mic/kg) CONDITION: Endotracheal intubation without muscle relaxation. ; Other complications of anaesthesia Other complications of anaesthesia PRIMARY OUTCOME: Ability of mask Ventilation. Timepoint: After drug infusion. Method of measurement: Chest wall movement. Blood pressure. Timepoint: 2 minutes after drug infusion, 5 minutes after of intubation. Method of measurement: mmHg with Mercury barometers. Heart rate. Timepoint: 2 minutes after drug infusion, 5 minutes after of intubation. Method of measurement: Heart rate in 1 minutes. Jaw relaxation. Timepoint: 90 seconds after drug infusion. Method of measurement: Examined by hand. Reaction to endotracheal intubation. Timepoint: During intubation. Method of measurement: Cough, Buckying. Vocal cord position. Timepoint: During intubation. Method of measurement: Observation. INCLUSION CRITERIA: INCLUSION CRITERIA: patients chosen for elective surgery, age range between 18‐50 years, ASA class I‐II of anesthesia. Exclusion criteria: Hypertension, Rising ICP, Coronary Artery Disease , Convulsion, Gastroesophageal reflux, Sensitive airway, Use of opioid and alcohol, Maxillofacial abnormalities , Difficult airway (mallempathy 3,4).