The effect of tulobuterol patches on the respiratory system after endotracheal intubation

BACKGROUND: Endotracheal intubation during anesthesia induction may increase airway resistance (R(aw)) and decrease dynamic lung compliance (Cdyn). We hypothesized that prophylactic treatment with a transdermal β2-agonist tulobuterol patch (TP) would help to reduce the risk of bronchospasm after placement of the endotracheal tube. METHODS: Eighty-two American Society of Anesthesiologists (ASA) category I or II adult patients showing obstructive patterns were divided randomly into a control and a TP group (n = 41 each). The night before surgery, a 2-mg TP was applied to patients in the TP group. Standard monitors were recorded, and target controlled infusion (TCI) with propofol and remifentanil was used for anesthesia induction and maintenance. Simultaneously, end-tidal carbon dioxide, R(aw), and Cdyn were determined at 5, 10, and 15 min intervals after endotracheal intubation. RESULTS: There was no significant difference in demographic data between the two groups. The TP group was associated with a lower R(aw) and a higher Cdyn, as compared to the control group. R(aw) was significantly lower at 10 min (P < 0.05) and 15 min (P < 0.01), and Cdyn was significantly higher at 5 min (P < 0.05) and 15 min (P < 0.01) in the TP group. A trend towards a lower R(aw) was observed showing a statistically significant difference 5 min after endotracheal intubation (P < 0.01) in each group. CONCLUSIONS: Prophylactic treatment with TP showed a bronchodilatory effect through suppressing an increase in R(aw) and a decrease in C(dyn) after anesthesia induction without severe adverse effects.

The EC50 of remifentanil to minimize the cardiovascular changes during head holder pinning in neurosurgery / 대한마취과학회지

BACKGROUND: During neuroanesthesia, head holder pinning commonly results in sympathetic stimulation manifested by hemodynamic changes, such as increased heart rate and arterial blood pressure. Remifentanil has been used successfully to control acute autonomic responses during neurosurgical procedures. The objective of this study was to determine effect-site concentration of remifentanil for suppressing the hemodynamic response to head holder pinning with the probability of 50% (EC50). METHODS: Forty-one ASA physical status I or II patients, between the ages of 20-70, who were scheduled for neurosurgery were recruited into this study. After arrival in the operating room, standard monitoring was applied throughout the study, which included a bispectral index monitor. Both propofol and remifentanil were administered by Target-control infusion device. The Dixon "up-and-down" sequential allocation method was used to determine the EC50 of remifentanil. RESULTS: The EC50 of remifentanil was 2.19 +/- 0.76 ng/ml by the turning point estimate (TPE). In probit analysis, EC50 was 2.42 ng/ml (95% CI : -0.62-4.66) and EC95 was 5.70 ng/ml (95% CI : 4.02-67.53). The EC50 estimator comes from isotonic regression is 2.90 ng/ml (95% CI : 1.78-3.65). The EC95 estimator comes from isotonic regression is 4.28 ng/ml (95% CI : 3.85-4.41). CONCLUSIONS: This study showed that EC50 of remifentanil was 2.19 +/- 0.76 ng/ml by TPE. EC50 was 2.42 ng/ml (95% CI -0.62-4.66) in probit analysis, as back up analysis. The EC50 estimator comes from isotonic regression is 2.90 ng/ml (95% CI : 1.78-3.65).

Effect of the separated airway on the Intubating condition in fiberoptic bronchoscope-guided intubation fiberoptic intubation using separated airway

BACKGROUND: Fiberoptic bronchoscope guided intubation is an important method of difficult airway management. The use of specific airways has been devised to assist the fiberoptic intubation. The authours compared effectiveness of separated airway with fiberoptic bronchoscope guided intubation and the hemodynamic responses. METHODS: 104 adult patients of American Society of Anesthesiologists grading (ASA) I-II who scheduled for surgery under general anesthesia were randomly divided into the Laryngoscope group (L group, n = 30) or the Fiberoptic bronchoscope group (F group, n = 36) or the Fiberoptic bronchoscope with separated airway (MF group, n = 38). A Fiberoptic bronchoscope guided intubation and a fiberoptic bronchoscope with separated airway and a direct laryngoscope was performed after inducing anesthesia. Intubation time, Jaw thrust incidence, mean blood pressure and heart rate after anaesthesia induction, at intubation and every two minute for a further 7 min were recorded. RESULTS: The intubation time was significantly shorter in the MF group (58.3 +/- 13.7 sec) than F group (71.9 +/- 22.1 sec). Jaw thrust incidence was lower in the MF group (60.5%) than F group (100%). The changes of MAPs and HRs during the observation were not significantly different in three group. CONCLUSIONS: Fiberoptic intubation using separated airway reduced intubation time and the incidence of jaw thrust.