Optimal Dose of Dexmedetomidine for Sedation During Spinal Anesthesia.

Optimal dose of dexmedetomidine for sedation during spinal anesthesia.

Korean J Anesthesiol. 2013 May; 64(5): 426-31
Ok HG, Baek SH, Baik SW, Kim HK, Shin SW, Kim KH

Sedation in spinal anesthesia can reduce patient’s anxiety and discomfort. Dexmedetomidine has a sedative, hypnotic, analgesic, and minimal respiratory depression effect. However, use of the dexmedetomidine is associated with prolonged recovery. This study was designed to investigate the optimal dose of intravenous dexmedetomidine for proper sedation with minimal recovery time in spinal anesthesia.One hundred twenty eight patients, aged 20-70 years (58.8 ± 0.7), were recruited. After performing the spinal anesthesia with hyperbaric bupivacaine (13 mg), a loading dose of dexmedetomidine (1 µg/kg) was administered for 10 min, followed by the maintenance infusion of the following: Group A (n = 33; normal saline), Group B (n = 35; dexmedetomidine 0.2 µg/kg/hr), and Group C (n = 39; dexmedetomidine 0.4 µg/kg/hr). Heart rate, blood pressure, and the bispectral index score (BIS) were recorded during the operation. In the recovery room, modified aldrete score (MAS) was measured.There were no significant differences in mean blood pressure and heart rate among the three groups. BIS was not significantly different among the three groups from baseline to 60 min after the infusion of dexmedetomidine. BIS were significantly increased in Group A after 70 and 80 min, and Group A and B after 90, 100, 110 min of dexmedetomidine infusion (P < 0.05). MAS was higher in Group A as compared to Group B and C, within 30 min after admission in the recovery room (P < 0.05).The loading dose (1 µg/kg/10 min) of dexmedetomidine was sufficient for surgery of less than 60 min. Dexmedetomidine infusion followed by maintenance dose (0.2 µg/kg/hr) was sufficient for surgery within 90 min. HubMed – depression


Gating of long-term potentiation by nicotinic acetylcholine receptors at the cerebellum input stage.

PLoS One. 2013; 8(5): e64828
Prestori F, Bonardi C, Mapelli L, Lombardo P, Goselink R, De Stefano ME, Gandolfi D, Mapelli J, Bertrand D, Schonewille M, De Zeeuw C, D’Angelo E

The brain needs mechanisms able to correlate plastic changes with local circuit activity and internal functional states. At the cerebellum input stage, uncontrolled induction of long-term potentiation or depression (LTP or LTD) between mossy fibres and granule cells can saturate synaptic capacity and impair cerebellar functioning, which suggests that neuromodulators are required to gate plasticity processes. Cholinergic systems innervating the cerebellum are thought to enhance procedural learning and memory. Here we show that a specific subtype of acetylcholine receptors, the ?7-nAChRs, are distributed both in cerebellar mossy fibre terminals and granule cell dendrites and contribute substantially to synaptic regulation. Selective ?7-nAChR activation enhances the postsynaptic calcium increase, allowing weak mossy fibre bursts, which would otherwise cause LTD, to generate robust LTP. The local microperfusion of ?7-nAChR agonists could also lead to in vivo switching of LTD to LTP following sensory stimulation of the whisker pad. In the cerebellar flocculus, ?7-nAChR pharmacological activation impaired vestibulo-ocular-reflex adaptation, probably because LTP was saturated, preventing the fine adjustment of synaptic weights. These results show that gating mechanisms mediated by specific subtypes of nicotinic receptors are required to control the LTD/LTP balance at the mossy fibre-granule cell relay in order to regulate cerebellar plasticity and behavioural adaptation. HubMed – depression


Association of galanin and major depressive disorder in the chinese han population.

PLoS One. 2013; 8(5): e64617
Wang YJ, Li H, Yang YT, Tie CL, Li F, Xu ZQ, Wang CY

This study aimed to investigate the association of galanin (GAL) gene and the development of depression in the Chinese Han population.A total of 700 patients with depression who met the diagnostic criteria of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) and 673 healthy controls were used in this study. Ligase detection reactions were performed on 10 selected single nucleotide polymorphism (SNP) sites in the GAL gene. A series of statistical methods were carried out to investigate the correlation between the GAL gene SNP and the patient susceptibility to depression.The SNPs of rs694066 in the GAL gene showed a positive correlation with MDD. Compared with the healthy controls, lower frequency of G/G genotype and higher frequency of A/G genotype were observed in rs694066 in MDD patients, a lower frequency of G-allele and higher frequency of A-allele were observed in rs694066. These correlations were more pronounced in the 376 female patients and 360 female control subjects than in the 324 male patients and 313 healthy male subjects.This study investigated the relationship between the GAL gene SNP and the susceptibility to depression in the Chinese Han population. The findings clearly indicate that the GAL gene polymorphism is closely correlated to the incidence of depression in the Chinese Han female patients. HubMed – depression


Depression and marital intimacy level in parents of infants with sleep onset association disorder: a preliminary study on the effect of sleep education.

Korean J Pediatr. 2013 May; 56(5): 211-7
Lee S, Rhie S, Chae KY

Sleep onset association disorder (SOAD) is a form of behavioral insomnia observed in children that is caused by inappropriate sleep training. SOAD typically disturbs the sleep of not only infants and children but also their parents. We investigated levels of depression and marital intimacy among parents of infants with typical SOAD, to understand the influence of SOAD on family dynamics, as well as examine ways for improving depression and marital intimacy through behavioral training.Depression and marital intimacy were assessed using the Beck Depression Inventory (BDI) and Waring Intimacy Questionnaire (WIQ). These measures were administered to 65 parents of infants (n=50) diagnosed with SOAD. We conducted sleep education and behavioral training for the parents and compared levels of depression and marital intimacy after 2-6 weeks of training.The 65 parents consisted of 50 mothers and 15 fathers. Depressive symptoms were higher among mothers than fathers (P =0.007). Marital intimacy was negatively correlated with depressive symptoms. Twenty-six parents were assessed again after sleep training. We found that mothers’ depressive symptoms and marital intimacy improved post training.SOAD can be detrimental to both infants and parents, especially for parents who sleep with their infants. For instance, disruption of sleep patterns in such parents can reduce marital intimacy. However, behavioral modification is an effective treatment for infants with frequent nighttime waking, as well as for diminishing the depressive symptoms of sleep-deprived parents. HubMed – depression