Effects of Neostigmine and Sugammadex on QT Interval and QT Dispersion

Dispersion of QT dispersion(QTD)in 12-lead electrocardiogram is a useful index for assessment of ventricular arrhythmia risk and cardiovascular event. To determine the effects of reversal of nondepolarizing neuromuscular blockade on cardiovascular event, we evaluated the QT interval QTD after reversal of the neuromuscular blockade by neostigmine or sugammadex.After obtaining the approval of the ethics committee of Dokkyo Medical University Hospital, 40 patients with ASA physical status I or II were allocated to following two groups. Patients in the groups N(n=16)and S(n=15)received combination of neostigmine(40?μg/kg)and atropine(20?μg/kg)or sugammadex(2?mg/kg)as a reversal of neuromuscular blockade after the operation under 1% sevoflurane anesthesia, respectively. The RR interval, QT interval(QT), corrected QT interval(QTc), QT dispersion and corrected QT dispersion(QTcD)were consecutively recorded using computerized measurement before and after administration of reversal agents in both groups.RR interval in the group N significantly decreased 1-4?min after reversal of the neuromuscular blockade, but not in the group S. However, in the groups N and S, QT interval, QTc interval, QTD and QTcD were not changed after reversal of the neuromuscular blockade. Moreover, there was no significant difference between both groups in QT interval, QTc interval, QTD and QTcD during the study.Our results suggest that neither neostigmine nor sugammadex may increase the risk of ventricular arrhythmia and cardiovascular events in reversal of the neuromuscular blockade under sevoflurane anesthesia

Comparison of Remifentanil and Landiolol on Hemodynamic and Plasma Catecholamine Responses to Tracheal Intubation

The purpose of this study is to compare remifentanil with landiolol to examine the effects of hemodynamic and plasma catecholamine responses to tracheal intubation. Sixty patients scheduled for elective surgery were randomly divided into three groups, to receive either normal saline( group C), a 1-minute loading infusion of remifentanil 0.5 m g/kg followed by an infusion of remifentanil 0.25/m g/kg/min during the study(group R), or a 1-minute loading infusion of landiolol 0.125 mg/kg followed by an infusion of landiolol0.04 mg/kg/min during the study (group L). After the 1-minute loading infusion of each drug, anesthesia was induced with intravenous injection of propofol 2 mg/kg, and vecuronium 0.1 mg/kg. Five minutes after the administration of each drug, tracheal intubation was performed within 30 seconds. Mean arterial pressure remained below the baseline value after tracheal intubation in group R, but not in groups L and C.Heart rate significantly increased after tracheal intubation in group C, but not in groups R and L. Plasma concentration of adrenaline remained below the baseline value after tracheal intubation in all groups, but it was significantly lower in group R, compared with other groups. Plasma concentration of noradrenaline significantlyincreased after tracheal intubation in groups L and C, but not in group R. Bispectral index in group R remained lower than that in groups L and C after tracheal intubation. Remifentanil may be preferableto landiolol to provide cardiovascular stability after tracheal intubation

NMDA Component of the Excitatory Synaptic Transmission of Neurons Containing Serotonin or GABA in the Ventrolateral Subdivision of the Periaqueductal Gray Matter of Mouse

The midbrain periaqueductal gray( PAG) plays a crucial role in the descending pain modulating system.NMDA receptors (NMDARs) and serotonergic and GABAergic neurons have been identified in the PAG and are involved in the descending pain-modulating pathway. We characterized the NMDA component of the excitatory synaptic transmission within the ventrolateral subdivision of the PAG( vlPAG) using a whole cell patch clamp technique and then detected the expression of tryptophan hydroxylase (TPH), serotonin synthesizing enzyme, and glutamate decarboxylase (GAD), GABA synthesizing enzyme to understand thevlPAG intrinsic neurotransmission. The NMDA/non-NMDA ratio and the decay time constant of theNMDA component of the non-serotonergic GABAergic neurons were significantly larger than those of nonserotonergicnon-GABAergic neurons and serotonergic GABAergic neurons. This suggests that the non-serotonergic GABAergic neurons might play an important role in the descending pain modulating system originated from the PAG. The decay time constant of the NMDA component of the non-serotonergic non-GABAergic neuron was significantly greater in the mouse with partial sciatic nerve ligation compared with the control mouse. These results suggest that the subunit composition of the NMDAR in the non-serotonergicnon-GABAergic neurons change during neuropathic pain

ザッシュ セイケン ニ オケル ワンシンケイソウ ブロック ガ ジョウシ ケツリュウ リョウ ニ オヨボ ス エイキョウ ニ ツ イテ

雑種成犬の腕神経叢ブロック(BPB)モデルを作製し,ブロック後の上肢血流量の変化について調べた.【方法】雑種雄性成犬を対象とし,全身麻酔下にBPB モデルを作製し,生理食塩水1 mL(生理食塩水群:8 例)と1%メピバカイン1 mL(局所麻酔薬群:8 例)投与後の正中動脈血流量(MABF)の変化を記録,比較検討した.BPB は,超音波下に21 ゲージ針を腕神経叢内に進め,電気刺激装置にて刺激を確認しながら薬液を注入し,測定終了時に頚部を開創してインジゴカルミン含有の薬液の神経叢内に限局した広がり確認した.BPB による上肢血流量の変化は超音波血流計を用いてMABF を測定することにより評価した.【結果】局所麻酔薬群では,薬液注入30 分後よりブロック側のMABF が有意に増加し,その増加は60 分後に最大値(136.7±35.3%)に達し,有意な血流増加は140 分後まで持続した.局所麻酔薬群のブロック反対側のMABF の変動は認められなかった.一方,生理食塩水群では,薬液注入後のMABF の変動は,ブロック側,反対側ともに認められなかった.【結語】雑種成犬のBPB を作製し,交感神経遮断によると考えられる上肢の動脈血流増加作用を確認した.The purpose of this study is to establish a model of brachial plexus block( BPB) in anesthetized dogs and evaluate changes in the arterial blood flow after BPB. Sixteen anesthetized dogs were enrolled into this study and divided into two groups as follows;M group( 1% mepivacaine 1 mL:n=8) and C group (physiological saline solution (PSS)1 mL:n=8). For BPB, a block needle was inserted into the left brachial plexus under ultrasonic imaging, the brachial plexus was identified using a nerve stimulator and the spread of drug solutions was confirmed by indigo carmine under dissection after the study. Changes in the arterial blood flow were evaluated by the median arterial blood flow (MABF) using the ultrasonic blood flowmeter. In group M,left MABF was significantly increased from 30 min to 120 min after BPB, and maximum increase in MABF was 136.7±35 % at 60 min after BPB. In group C, changes in left MABF were not observed during the study. In both groups, right MABF was not changed after BPB. Our results suggest that BPB may have a vasodilating effect induced by sympathetic block