Influence of GlideScope assisted endotracheal intubation on intraocular pressure in ophthalmic patients

Abstract

Background:Traditional Macintoch laryngoscopy is known to cause a rise in intraocular pressure (IOP), tachycardia and hypertension. These changes are not desirable in patients with glaucoma and open globe injury. GlideScope is a video laryngoscope that functions independent of the line of sight, reduces upward lifting forces for glottic exposure and requires less cervical neck movement for intubation, making it less stimulating than Macintosh laryngoscopy.Aim:The aim was to assess the variations in IOP and hemodynamic changes after GlideScope assisted intubation.Materials and Methods:After approval of the local Institutional Research and Ethical Board and informed patient consent, 50 adult American Society of Anesthesiologist I and II patients with normal IOP were enrolled in a prospective, randomized study for ophthalmic surgery requiring tracheal intubation. In all patients, trachea was intubated using either GlideScope or Macintoch laryngoscope. IOP of nonoperated eye, heart rate and blood pressure were measured as baseline, 1 min after induction, 1 min and 5 min after tracheal intubation.Results:IOP was not significantly different between groups before and after anesthetic induction and 5 min after tracheal intubation (P = 0.217, 0.726, and 0.110 respectively). The only significant difference in IOP was at 1 min after intubation (P = 0.041). No significant difference noted between groups in mean arterial pressure (P = 0.899, 0.62, 0.47, 0.82 respectively) and heart rate (P = 0.21, 0.72, 0.07, 0.29, respectively) at all measurements.Conclusion:GlideScope assisted tracheal intubation shown lesser rise in IOP at 1 min after intubation in comparison to Macintoch laryngoscope, suggesting that GlideScope may be preferable to Macintosh laryngoscope.

Use of the GlideScope does not lower the hemodynamic response to tracheal intubation more than the Macintosh laryngoscope: a systematic review and meta-analysis

“…Twelve of these studies were excluded because they did not investigate hemodynamic response (n = 5), compared laryngoscopes other than the GlideScope and Macintosh (n = 6), or involved use of a double-lumen tube (n = 2). Thirteen trials [ 10 , 21 – 32 ] were confirmed to meet the inclusion criteria (Fig. 1 ) and are summarized in detail in Table 1 (see Table 1 , which illustrates the characteristics of trials included in this meta analysis).…”

“…Eight trials were for patients with American Society of Anesthesiologists-Physical Status classification 1-2. [ 10 , 21 , 25 – 30 ] There were 4 trials including American Society of Anesthesiologists-Physical Status classification 3 patients. [ 22 – 24 , 31 ] In our study, 11 out of 13 trials were tracheal intubated with oral intubation.…”

“…[ 22 – 24 , 31 ] In our study, 11 out of 13 trials were tracheal intubated with oral intubation. [ 10 , 21 – 26 , 29 , 31 , 32 ] Nasal intubation was only 2 trials. [ 28 , 30 ] In the assessment of airways pre intubation, 10 trials were evaluated as normal airways.…”

“…For example, Ahmad et al reported that suppression of the increase in heart rate after tracheal intubation with normal airway patients was better when the GlideScope was used instead of the Macintosh laryngoscope. [ 10 ] However, other reports have shown no difference in hemodynamic responses during tracheal intubation with both laryngoscopes. [ 11 , 12 ] Further, other studies reported to better suppression of the hemodynamic response during tracheal intubation when the Macintosh laryngoscope than the GlideScope was used.…”

“…One small study found that the hemodynamic response was less pronounced during tracheal intubation with the GlideScope than with the Macintosh laryngoscope [ 10 ] and attempts to confirm this finding have yielded mixed results. For example, Ahmad et al reported that suppression of the increase in heart rate after tracheal intubation with normal airway patients was better when the GlideScope was used instead of the Macintosh laryngoscope.…”