Anesthesia and analgesia
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Anesthesia and analgesia · Nov 2011
The effect of a new water-soluble sedative-hypnotic drug, JM-1232(-), on long-term potentiation in the CA1 region of the mouse hippocampus.
JM-1232(-) {(-)-3-[2-(4-methyl-1-piperazinyl)-2-oxoethyl]-2-phenyl-3,5,6,7-tetrahydrocyclopenta[f]isoindol-1(2H)-one} is a new water-soluble sedative-hypnotic drug with affinity for the benzodiazepine binding site on γ-aminobutyric acid A receptors. The effects of JM-1232(-) on synaptic transmission in the brain are not known. In the present study, we investigated the effects of JM-1232(-) on synaptic transmission, synaptic plasticity (i.e., long-term potentiation [LTP] and paired-pulse facilitation), and excitatory/inhibitory postsynaptic currents (EPSCs/IPSCs) of pyramidal neurons in the CA1 region of mouse hippocampal slices. ⋯ JM-1232(-) enhances synaptic inhibition and impairs LTP and paired-pulse facilitation in area CA1 of the mouse hippocampus. These effects were mediated by benzodiazepine binding sites on γ-aminobutyric acid A receptors.
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Anesthesia and analgesia · Nov 2011
The accuracy of noninvasive hemoglobin measurement by multiwavelength pulse oximetry after cardiac surgery.
In March 2008, a new multiwavelength pulse oximeter, the Radical 7 (Rad7; Masimo Corp., Irvine, CA), was developed that offers noninvasive measurement of hemoglobin concentration. Accuracy has been established in healthy adults and some surgical patients, but not in cardiac surgery intensive care patients, a group at high risk of postoperative bleeding events and anemia in whom early diagnosis could improve management. ⋯ Our study demonstrates poor correlation between hemoglobin measured noninvasively by multiwavelength pulse oximetry and a laboratory hematology analyzer. The difference was greater when the pulse oximetry perfusion index was low, as may occur in shock, hypothermia, or vasoconstriction patients. The multiwavelength pulse oximetry is not sufficiently accurate for clinical use in a cardiovascular intensive care unit.
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Anesthesia and analgesia · Nov 2011
Randomized Controlled TrialThe addition of lidocaine to bupivacaine does not shorten the duration of spinal anesthesia: a randomized, double-blinded study of patients undergoing knee arthroscopy.
The duration of spinal anesthesia with bupivacaine is often too long for day surgery. A recent study of patients presenting for transurethral surgery suggested that the addition of a small amount of lidocaine to intrathecal hyperbaric bupivacaine could shorten the duration of the sensory and motor blocks. In this prospective, randomized double-blind study we investigated these findings in patients undergoing unilateral knee arthroscopy. ⋯ We did not confirm, in patients undergoing knee arthroscopy, that the addition of a small dose of lidocaine to intrathecal hyperbaric bupivacaine could shorten the duration of sensory or motor blocks or time to readiness for discharge from the postanesthesia care unit.
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Anesthesia and analgesia · Nov 2011
Randomized Controlled Trial Comparative StudyA randomized crossover study to determine the effect of a 30° head-up versus a supine position on the functional residual capacity of term parturients.
Airway management continues to pose challenges to the obstetric anesthesiologist. Functional residual capacity (FRC), which acts as an oxygen reservoir, is reduced from the second trimester onwards and is exacerbated in the supine position. Mechanisms to increase FRC may delay the onset of hypoxemia during periods of apnea. Values for changes in FRC in term parturients in semierect positions are unknown. We hypothesized that the FRC of healthy term parturients would increase significantly in the 30° head-up position in comparison with the supine position. ⋯ We have demonstrated that the FRC of healthy term parturients increases significantly in the 30° head-up position in comparison with supine.
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Anesthesia and analgesia · Nov 2011
Comparative StudyA prospective survey of patient-controlled epidural analgesia with bupivacaine and clonidine after total hip replacement: a pre- and postchange comparison with bupivacaine and hydromorphone in 1,000 patients.
Patient-controlled epidural analgesia (PCEA) with bupivacaine and hydromorphone provides high quality analgesia after orthopedic surgery but is associated with a frequent incidence of opioid-related side effects (15%-30%). Epidural clonidine has a different side effect profile, but there are no large surveys documenting its use. We performed this prospective survey to evaluate analgesia and the side effect profile in total hip replacement patients before and after a systematic change from PCEA with bupivacaine/hydromorphone to bupivacaine/clonidine. ⋯ The systematic changeover from epidural hydromorphone to clonidine produced mixed results without obvious superiority. The VPS at rest was reduced only on postoperative day 0; pruritus was reduced, but hypotension was increased. On the basis of medical staff preference, we discontinued the systematic change and returned to our previous standard solution of bupivacaine and hydromorphone for PCEA after total hip replacement.