Yawning elicited by IV anesthetic induction was related to a transient increase during the continuing decrease in the electroencephalographic bispectral index value (sensitivity and specificity, 77% and 80%, respectively). This type of yawning may be a clinical indicator of a transient arousal-shift during progressive loss of consciousness.

Purpose:To determine how the probability of fentanyl-induced cough is affected by patient characteristics and/or anesthetic technique. Methods:We analyzed data from a cohort of 1,311 adult patients undergoing elective surgery under general anesthesia, accompanied by iv fentanyl. The following data were collected: patient demographics, history of cigarette smoking, presence of bronchial asthma or chronic obstructive pulmonary disease, administration of angiotensin converting enzyme inhibitors; and anesthetic technique, including: preanesthetic anxiolytic medication, prior use of atropine, epidural lidocaine, a priming dose of vecuronium, and the dose of iv fentanyl. Associations between individual variables in the clinical evaluation model and the likelihood of fentanyl-induced cough were characterized by calculating odds ratios. Multiple logistic regression analysis was used to examine the independent contribution of each variable while controlling for all variables.Results: Fentanyl-induced cough was independently associated with the following: aging, cigarette smoking, a prior epidural injection of lidocaine, and a priming dose of vecuronium. Fentanyl-induced cough was unaffected by gender, the presence of either bronchial asthma or chronic obstructive pulmonary disease, or prior use of atropine. Conclusions:Fentanyl-induced cough may be suppressed by aging, cigarette smoking, prior epidural injection of lidocaine, or a priming dose of vecuronium. These findings may allow insights into the mechanism of this phenomenon, thereby leading to its prevention. Objectif