Tae Ho Jang

The cardiovascular effects of midazolam co-induction to propofol for induction in aged patients.

Background The aim of this study was to investigate whether a small dose of midazolam and lessening the propofol dosage could prevent cardiovascular change at tracheal intubation for induction in aged patients. Methods Eighty patients over 65 years (ASA physical status 1, 2) scheduled for elective surgery received general anesthesia with remifentanil and propofol or midazolam. Patients in group P (n = 40) were induced with 0.9% NaCl 0.03 ml/kg, propofol 1. 2 mg/kg and remifentanil. Patients in group MP (n = 40) were induced with midazolam 0.03 mg/kg, propofol 0.8 mg/kg and remifentanil. The time taken to reach loss of consciousness (LOC) and the value of bispectral index score (BIS) at LOC were recorded. After LOC, 0.8 mg/kg of rocuronium was given and tracheal intubation was performed. The mean blood pressure (MBP) and heart rate (HR) were recorded before induction as the base value, before intubation, immediately post-intubation and 3 minutes after intubation. Results Compared with the base values, MBP at before intubation and 3 minutes after intubation was significantly decreased in group P and group MP (P < 0.05). Compared with group P, the decrease of MBP was significantly less at before intubation, immediately after intubation and 3 minutes after intubation in group MP (P < 0.05). The time taken to reach LOC was significantly decreased in group MP compared with that in group P (P < 0.05). There were no significant differences of HR at any time between the two groups. Conclusions Co-induction with midazolam and propofol could prevent a marked BP decrease at tracheal intubation for induction in aged patients.

Difference of the hemodynamic changes induced by tracheal intubation using remifentanil between smokers and nonsmokers

Background It was well-known that smoking affects the cardiovascular system, and remifentanil can suppress the sympathetic stimulations induced by tracheal intubation. The purpose of this study was to investigate whether there was any difference in the hemodynamic changes induced by tracheal intubation with using remifentanil between smokers and nonsmokers. Methods Eighty patients were enrolled: male smokers (MS), male nonsmokers (MN), female smokers (FS) and female nonsmokers (FN). Anesthesia was induced with diluted remifentanil (20 µg/ml) at a rate of 10 µg/kg/hr using an infusion pump, and 2 min later, midazolam 0.05 mg/kg and propofol 0.8 mg/kg were injected for achieving unconsciousness. Rocuronium 1 mg/kg was used for muscle relaxation, and tracheal intubation was performed 2 min after rocuronium injection. After tracheal intubation, the remifentanil was decreased to 2 µg/kg/hr. The mean arterial pressure (MAP) and heart rate (HR) were checked before induction, on unconsciousness, just before intubation, just after intubation and 1, 2 and 3 minutes after intubation, and these values were compared between the groups. Results In men, the MAP and HR just after intubation and at 1, 2 and 3 minutes after intubation in Group MS were significantly higher than those of Group MN (P < 0.05). For the women, the HR in both groups (the FS and FN groups) were increased just after intubation and 1, 2 and 3 minutes after intubation compared with that at the baseline, respectively, but there was no difference between the two groups. Conclusions There was a difference of the hemodynamic changes induced by tracheal intubation with using remifentanil between the male smokers and nonsmokers, but not in women.