Identification of independent predictors for intravenous thiopental-induced yawning.

PURPOSE: To explore risk factors for the yawning response induced by the intravenous administration of thiopental during the induction of general anesthesia. METHODS: We analyzed data from a cohort of 1322 patients who underwent elective surgery under general anesthesia plus intravenous thiopental. The data collected were: (a) the patients' demographic findings (age, sex, height, weight, cigarette smoking, hypertension, and presence of cerebral lesion), and (b) anesthesia-related findings (the kind of preanesthetic medication, i.e., atropine, epidural lidocaine, priming dose of vecuronium, fentanyl, and the dose of intravenous thiopental). An association between an individual variable in the evaluation model and the likelihood of thiopental-induced yawning behavior was characterized by means of the odds ratio. Multiple logistic regression was used to examine the independent contribution of each candidate variable, while controlling for all variables. RESULTS: After the intravenous administration of thiopental, 461 patients exhibited a yawning response. The probability of this response was decreased by the prior use of intravenous fentanyl, by female sex, and by premedication with clonidine, but the probability was unaffected by premedication with hydroxyzine, by the prior use of atropine, or by the presence of hypertension or a cerebral lesion. CONCLUSION: Thiopental-induced yawning may be suppressed by female sex, prior use of intravenous fentanyl, and premedication with clonidine. These findings may allow insights into the physiologic and pharmacological aspects of yawning in humans, thereby leading to the development methods to prevent thiopental-induced yawning.

Role of basal ganglia-brainstem systems in the control of postural muscle tone and locomotion.

This chapter argues that a basal ganglia-brainstem system throughout the mesopontine tegmentum contributes to an automatic control of movement that operates in conjunction with voluntary control processes. Activity of a muscle tone inhibitory system and the locomotion executing system can be steadily balanced by a net excitatory cortical input and a net inhibitory basal ganglia input to these systems. We further propose that dysfunction of the basal ganglia-brainstem system, together with that of the cortico-basal ganglia loop, underlies the pathogenesis of motor disturbances expressed in basal ganglia diseases.

Potentially harmful sleep habits of 3-year-old children in Japan.

To examine the sleep habits of 3-year-old children, we questioned guardians during a routine health examination for 3-year-old children at a public health center. According to the 1105 questionnaires analyzed, the proportion of children who fell asleep at 10 p.m. or later was 49.6%. The nocturnal sleep onset time was significantly correlated with the wake-up time in the morning and was significantly negatively correlated with the nocturnal sleep duration. The average daily total sleep duration (nocturnal sleep duration + nap duration) of regular nap-takers showed a significant negative correlation with the nocturnal sleep onset time. The average values for height, weight, and body mass index (BMI) were not correlated with the nocturnal sleep onset time. Children who went to sleep later got less sleep than those who went to sleep earlier. Because sleep debt has a harmful impact on older children and adults, late sleep onset may have adverse health consequences in young children.