Journal of anesthesia
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Journal of anesthesia · Jun 1997
Correlation between the anesthetic potency of local anesthetics and their binding ability to a model membrane.
The interaction between various local anesthetics and the phospholipid membrane was examined by(1)H-NMR (nuclear magnetic resonance) spectroscopy. By examining the chemical shift value in order to measure the extent of proximity of various local anesthetics to the membrane, it was determined that tetracaine (10.7 Hz) was closest to the membrane, followed in descending order of proximity by dibucaine (8.8 Hz), bupivacaine (4.4 Hz), propitocaine (4.4 Hz), and lidocaine (3.5 Hz). ⋯ In addition, we studied the interaction of local anesthetics with the membrane by examining the broadening of the half-width, and determined that tetracaine (12.2 Hz) bound closest to the membrane, followed in descending order of proximity by dibucaine (11.0 Hz), bupivacaine (9.6 Hz), propitocaine (9.0 Hz), lidocaine (8.8 Hz), procaine (8.0 Hz) and cocaine (7.9 Hz). In the present study, the binding ability of local anesthetics to the phospholipid membrane was found to be directly in parallel with the potency and toxicity of the anesthetic.
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Journal of anesthesia · Jun 1997
Possible evaluation of hemodynamic effects of the potassium channel opener KRN2391 on induced hypotension in dogs.
KRN2391 is potassium channel opener with a nitrate moiety which possesses potent vasodilatory action. The hemodynamic profiles of KRN2391-induced hypotension are still not well understood. The aim of this study was to investigate the potential use of KRN2391 for induced hypotension. ⋯ Left ventricular maximum dP/dt increased significantly during and after induced hypotension. Right atrial and mean pulmonary artery pressures increased significantly, whereas pulmonary capillary wedge pressure remained unchanged. The results of the present study show that KRN2391 is effective in reducing afterload during induced hypotension, and suggest that the hemodynamic profiles of KRN2391-induced hypotension are a hyperdynamic state as expressed by twofold increases in CI concomitant with the increase in right ventricular filling pressures.