Respiration and The Airway With Supraglottic Airway Devices

The study will be carried on adult female patients to reduce variability in size of the chosen device to enable the investigators to analyze the performance parameters of the two devices with greater authority. The study will be done on anesthetized paralyzed adult female patients undergoing elective gynecological operations that require neuromuscular block but not necessarily tracheal intubation. The investigators will recruit 40 adult female(18-55 years old, ASAI&II) patients to a prospective randomized crossover clinical trial. Patients with history of upper respiratory tract infections, obstructive sleep apnea , potentially full stomach( trauma, morbid obesity BMI> 35, pregnancy, history of gastric regurgitation and heart burn), those with esophageal reflux (hiatus hernia), and those of coagulation disorders will be excluded from the study. All patients will be assessed pre-operatively El-Ganzouri airway score to assess the expected difficulty of intubation and patients with airway scores ≥ 5 will be excluded from the study.The patients will be randomly allocated into two groups(the SP-Blocker group & the P-LMA group; each group is 40 patients) using computer generated program . An online randomization program (http://www.randomizer.org) will be used to generate random list and to allocate patients into the study groups. Random allocation numbers will be concealed in opaque closed envelops. The patient and investigator assessing study outcomes will all be blinded to the study groups allocation.