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

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.

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

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.

Arterial Blood Pressure and Heart Rate Response to Lightwand or Direct Laryngoscopy for Endotracheal Intubation / 대한마취과학회지

BACKGROUND: Tracheal intubation commonly results in sympathetic stimulation manifested by increased heart rate and arterial blood pressure. This study was carried out to determine whether lightwand would result in less hemodynamic changes than direct laryngoscopy. METHODS: With informed consent, fourty healthy female patients scheduled of elective surgical procedures were randomly allocated into two groups; lightwand (LW) or direct laryngoscopy (DL) group. Mean arterial pressure (MAP) and heart rate (HR) were recorded upon arrival. Under a standardized anesthetic technique, the patients were intubated either with no. 3 curved blade direct laryngoscopy (DL group) or with lightwand (LW group). The MAP and HR were recorded before intubation and every 1 minutes following intubaion. Time to intubation (TTI) was also recorded. All patients were intubated by a same fourth grade resident. RESULTS: Fourty patients were studied. Every intubation was successed in first attempt. The TTI was significantly shorter in LW group. Even while there was no significant difference in HR changes, there was significant difference in the increase of MAP following intubation. The increase of MAP was significantly greater with DL than with LW. CONCLUSIONS: This study suggests that lightwand intubation requires shorter TTI and may give rise to less blood pressure change than direct laryngoscopy. So we found no difference in disadvantage and may offers advantage in terms of hemodynamic stability.