Effective doses of cisatracurium in the adult and the elderly.

Background: There are few information about the differences of the effective dose (ED) of cisatracurium between the adult and the elderly. We investigated the ED and the onset time of cisatracurium in the adults and the elderly.

Methods: We studied two hundred patients of the adults aged 20 through 64 years and the elderly aged ≥ 65 years, with American Society of Anesthesiologists physical status I or II.

Effectiveness of Modal Decomposition for Tapping Atomic Force Microscopy Microcantilevers in Liquid Environment.

The modal decomposition of tapping mode atomic force microscopy microcantilevers in liquid environments was studied experimentally. Microcantilevers with different lengths and stiffnesses and two sample surfaces with different elastic moduli were used in the experiment. The response modes of the microcantilevers were extracted as proper orthogonal modes through proper orthogonal decomposition.

The effect of high concentration of magnesium with ropivacaine, gentamicin, rocuronium, and their combination on neuromuscular blockade.

Background: Magnesium, ropivacaine, gentamicin, and rocuronium block neuromuscular (NM) transmission by different mechanisms. Therefore, concurrent administration of these agents may induce prolonged muscle paralysis via synergistic interaction. This study investigated the efficacy and safety of NM block caused by the administration of high concentrations of magnesium in combination with ropivacaine, gentamicin, and rocuronium.

Do bupivacaine, clindamycin, and gentamicin at their clinical concentrations enhance rocuronium-induced neuromuscular block?

Background: Bupivacaine, clindamycin, and gentamicin inhibit neuromuscular (NM) conduction. When they are combined, they may synergistically reduce the effective concentration of each to the therapeutic concentration in augmenting rocuronium-induced NM block. Thus, the aim of this study was to investigate whether combinations of the three drugs, at around their therapeutic concentrations, potentiate rocuronium-induced NM block.

At therapeutic concentration bupivacaine causes neuromuscular blockade and enhances rocuronium-induced blockade.

Background: Partially paralyzed patients may be placed in the risk of pharyngeal dysfunction. Bupivacaine acts as acetylcholine receptor ion channel blocker and may synergistically interact with rocuronium to augment NM blockade. Thus, this study aims to elucidate whether or not, at a therapeutic concentration, bupivacaine by itself may cause NM blockade and reduce an effective concentration of rocuronium.

The antagonistic effect of neostigmine on rocuronium-, clindamycin-, or both-induced neuromuscular blocking in the rat phrenic nerve-hemidiaphragm.

Background: Neostigmine augments clindamycin-induced neuromuscular block and antagonizes rocuronium-induced neuromuscular block; however, it remains unclear whether neostigmine enhances the neuromuscular blocking (NMB) that is caused by combinations of rocuronium and clindamycin. The intent of this study was to determine whether neostigmine potentiates the muscle relaxation that is induced by combinations of rocuronium and clindamycin and to estimate whether both clindamycin and rocuronium have synergistic actions on NMB.

Methods: Forty-one left phrenic nerve-hemidiaphragms (from male Sprague-Dawley rats, 150-250 g) were mounted in Krebs solution.

Drug interaction: focusing on response surface models.

Anesthesiologists have been aware of the importance of optimal drug combination long ago and performed many investigations about the combined use of anesthetic agents. There are 3 classes of drug interaction: additive, synergistic, and antagonistic. These definitions of drug interaction suggest that a zero interaction model should exist to be used as a reference in classifying the interaction of drug combinations.

Stress-induced cardiomyopathy during ophthalmologic surgery: A case report.

Stress-induced cardiomyopathy or Takotsubo cardiomyopathy is a recently described clinical entity which is associated with a chest pain occurring during a stress, an abnormal ECG and/or an increase in the troponin blood level and a transient left ventricular dysfunction. Transient left ventricular dysfunction generally involves the midsection and the apex of the heart with an akinesis. We reported a case of a 55-year-old female patient who developed a stress-induced cardiomyopathy after local epinephrine use during ophthalmologic surgery.

Analysis of the rocuronium-vecuronium interaction on tetanic fade based on a generalized response surface model with varying relative potencies.

Background: Some studies have shown that rocuronium and vecuronium have additive, or synergistic effects on muscle relaxation based on the Loewe additivity. Therefore, we performed a fit of tetanic fade data to a generalized response surface model with varying relative potencies proposed by Kong and Lee (KLGRS) to evaluate the usefulness of KLGRS for capturing the interspersed drug interactions and to characterize the interaction between the two drugs.

Methods: Left phrenic nerve-hemidiaphragms (Male Sprague-Dawley rats, 150-250 g) were mounted in Krebs solution.

Calcium and neostigmine antagonize gentamicin, but augment clindamycin-induced tetanic fade in rat phrenic nerve-hemidiaphragm preparations.

Purpose: A reduction in acetylcholine release induced by gentamicin may limit neostigmine-induced increases in acetylcholine concentration in the neuromuscular junction. An increase in acetylcholine concentration caused by neostigmine and calcium may enhance the use-dependent ion channel block of the nicotinic acetylcholine receptor caused by clindamycin. The purpose of this study was to determine whether calcium and neostigmine antagonize the neuromuscular blockade caused by gentamicin and augment the blockade caused by clindamycin during both single-twitch (0.

Surface passivation of CdS/Zn2SiO4 nanocomposites prepared by a wet chemical route.

Highly luminescent CdS/Zn2SiO4 nanocrystals were prepared by a wet chemical method. The effect of surface passivation was observed in photoluminescence measurements of CdS nanocrystals embedded in colloidal nanocrystallite or amorphous Zn2SiO4 matrix. The resultant luminescent emission of as-prepared CdS/Zn2SiO4 nanocomposite thin films displays two distinct components.