Comparison of the effects of intubation with a Machintosh Laryngoscope, McGrath videolaryngoscope and C-Mac videolaryngoscope on intra-ocular pressure, optic nerve sheath diameter and haemodynamic parameters

Background: Optic nerve sheath diameter (ONSD) indirectly reflects intracranial pressure (ICP). Measurement of optic nerve sheath diameter (ONSD) is a non-invasive method. We aimed to compare the effects of the Macintosh laryngoscope, McGrath videolaryngoscope, and C-MAC videolaryngoscope on intracranial pressure (ICP), intraocular pressure (IOP), and hemodynamic parameters, and to identify the laryngoscope associated with the smallest increase in ICP and IOP. Methods: The study included a total of 120 patients aged ≥18 years. Patients were assigned to three groups according to the type of laryngoscope used. IOP, ONSD, and vital parameters were measured before laryngoscopy (T1), directly after intubation (T2), at the 5th (T3) and 10th (T4) minutes after intubation. Results: In both eyes, the increase in IOP at T2 was lower in the McGrath videolaryngoscope group compared to the other groups. ONSD values in the Macintosh laryngoscope group were significantly higher at T2, T3, and T4 compared to the McGrath and C-MAC groups (p < 0.05). Conclusions: The McGrath videolaryngoscope may be more advantageous in patients at risk of increased ICP and IOP. Furthermore, intubation with the McGrath videolaryngoscope appears to be associated with more stable hemodynamic parameters than those observed with the Macintosh and C-MAC laryngoscopes. Keywords: macintosh laryngoscope; mcGrath videolaryngoscope; optic nerve sheath diameter