Comparative Study of Light Wand and Direct Laryngoscope: Correlation of Time to Intubation and Thyromental Distance, and Change of Blood Pressure and Heart Rate after Intubation / 대한마취과학회지

ABSTRACT

BACKGROUND: Direct laryngoscope may be less useful under conditions of limited visualization. Light wand is a lighted stylet to transilluminate neck tissues allowing intubation without visualization. Thus, difficult intubation due to anatomy can be overcome. For comparison of light wand and direct laryngoscope, we checked time to intubation (TTI), success rate, relation of TTI and thyromental distance (TMD), and change of blood pressure and heart rate after intubation. METHODS: We selected and randomly allocated sixty adults to direct layngoscope group (D) and light wand group (L). Without premedication, propofol and vecuronium were injected for intubation. Time to intubation was measured from the time of grasping direct laryngoscope or light wand until the time of inserting endotracheal tube into trachea. We checked the change of blood pressure and heart rate after intubation, and studied the correlation of TTI and TMD. RESULTS: TTI was 16.5 sec (6.53~115.3 sec) for group D and 11.8 sec (4.31~36.0 sec) for group L. There was no significant difference between the groups. The rise of blood pressure and heart rate was less with light wand. There was a correlation of [TTI]=1248- 388[TMD]-30[TMD]2 in group L patients whose TMD is less than 7 cm. CONCLUSION: Compared with direct laryngoscope, light wand is as easy to use and can be more effective especially for patients whose anatomy may make intubation difficult or whose cardiovascular system is unstable.