Comparison of the effects of the McGRATH MAC, C-MAC, and Macintosh laryngoscopes on the intraocular pressures of non-ophthalmic patients: A prospective, randomised, clinical trial.

Abstract Introduction In this prospective, randomised study, we compared the effects of the Macintosh, McGRATH MAC, and C-MAC laryngoscopes on intraocular pressure (IOP) and hemodynamics of nonophthalmic patients during endotracheal intubation. Methods 120 adult patients undergoing nonophthalmic surgeries performed in the supine position under general anesthesia requiring orotracheal intubation, were included in this study. The patients were separated randomly and prospectively into 3 groups: Macintosh group (n = 40), McGRATH MAC group (n = 40), and C-MAC group (n = 40). Mean Arterial Pressure (MAP), Heart Rate (HR) and IOP of left and right eye were measured at specified times. Results There were no significant differences with regard to patients characteristics. After intubation, the HR increased significantly in the Macintosh group when compared to the other groups (p = 0.001) and the MAP increased significantly in the Macintosh group when compared to the McGRATH MAC group (p = 0.001) and the C-MAC group (p  Additionally, there was a significant difference between the McGRATH MAC group and C-MAC group in the IOP values of the eyes after intubation (p  Conclusions In this study, we concluded that the C-MAC VL may be preferable when compared to the Macintosh and McGRATH MAC laryngoscopes for use in ophthalmic patients in whom a rise in the IOP is undesirable.