Objective: To compare I–Gel versus endotracheal tube effects on hemodynamic stability and intraocular pressure in patients undergoing elective ophthalmological surgeries. Study Design: Quasi-experimental study. Place and Duration of Study: Armed Forces Institute of Ophthalmology, Rawalpindi Pakistan, from Nov 2019 to Oct 2020. Methodology: A total of 108 patients undergoing elective ophthalmological surgeries under general anesthesia from both genders, age range between 18-45 years, American Society of Anesthesiologists status I or II were included. General anesthesia given following standard procedures and monitoring. Heart rate, Systolic & Diastolic blood pressure monitored and intraocular pressure measured in each eye with Reichert ton open at baseline, upon insertion of airway device and 5 minutes after insertion. Results: Total 108 patients enrolled in the study with a mean age of 37.74 ± 6.0 years and age-range of 18-45. Heart rate at Insertion in I-Gel group was 78.14 ± 3.41 beats per minute whereas in intubated group was 97.20 ± 2.84 beats per minute, mean systolic blood pressure at insertion in group A and B was 115.28 ± 5.3 and 130.44 ± 2.81mm of Hg respectively. Intraocular pressure at insertion right eye in group A and B was 12.04 ± 0.48 and 17.98 ± 0.42 mm of Hg respectively. Intraocular pressure at insertion left eye in group A was 12.12 ± 0.45 whereas in group B was 17.95 ± 0.38mm of Hg (p-value=0.001). Conclusion: I–Gel provides better hemodynamic profile and intraocular pressure stability when compared with endotracheal tube.

The creep ageing process can have a significant influence on the mechanical properties of aluminum alloys. In the present work, microstructural analysis and mechanical testing were implemented to characterize the age hardening effect and microstructure evolution, and to investigate how the stress applied under creep ageing conditions can affect a material’s microstructure. The curves depicting yield strength in relation to creep ageing time suggested that the stress applied in creep ageing can result in a reduction of the strength of aluminum alloy 7050; the yield strength decreases with increasing applied stress. Microstructural analysis by transmission electron microscopy (TEM) revealed that by applying stress, the growth and coarsening rate of the Guinier-Preston (GP) zones and η′ precipitates can be sped up. Even after pure/creep ageing for 8 h, there are still some GP zones in the aluminum matrix, demonstrating that the GP zones’ nucleation is a continuous process.