Background: Endotracheal intubation during anesthesia induction may increase airway resistance (Raw) 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, Raw, 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 Raw and a higher Cdyn, as compared to the control group. Raw 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 Raw 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 Raw and a decrease in Cdyn after anesthesia induction without severe adverse effects.
Keywords: Bronchospasm; Endotracheal Intubation; Tulobuterol Patch.