Anesthesiology
-
Fentanyl is used in anesthetic protocols for swine, but there are no reports on its potency in this species. This study measured the extent to which fentanyl reduces the minimum alveolar concentration of isoflurane (MACISO) in swine. ⋯ These fentanyl dosages are larger than those commonly used in humans and other species. Anesthetic protocols using fentanyl for swine should be designed with the knowledge that a fentanyl infusion of 200 micrograms.kg-1.h-1 contributes approximately a 50% MACISO equivalent.
-
Opioids are used by patients who have conditions ranging from the acute pain of surgery and chronic cancer pain to substance abuse. Despite their widespread use and considerable experimental data about them, little is known about how opioids may alter in vivo immunity in humans. This study was designed to evaluate the in vivo effect of morphine on human peripheral blood immune functions. ⋯ These results suggest that morphine administration, at doses within the range of analgesic use, can cause measurable suppression of some components of the human cellular immune system.
-
Inhalational anesthetics inhibit hypoxic pulmonary vasoconstriction (HPV) in vivo and in vitro with a half-maximum inhibiting effect (ED50) within concentrations applied for general anesthesia. Because it is unknown whether desflurane acts likewise, we studied its effect on HPV in isolated blood-perfused rabbit lungs and compared its ED50 with that of halothane. ⋯ Assuming that 1 minimum alveolar concentration (MAC) values of desflurane and halothane for rabbits are 8.9% and 1.39%, respectively, this study yields ED50 values for the inhibition of HPV of approximately 1.6 MAC for desflurane and 1.2 MAC for halothane (P not statistically significant).
-
Randomized Controlled Trial Multicenter Study Clinical Trial
Postoperative pain control with a new transdermal fentanyl delivery system. A multicenter trial.
A new transdermal delivery system for fentanyl is available in two strengths: 70-80 and 90-100 micrograms.kg-1.h-1 (40- and 60-cm2 patches, respectively). Their short onset and 24-h drug delivery make them attractive for postoperative pain control. ⋯ Concern exists regarding the side effects of this this new transdermal fentanyl patch. Therefore, this new patch will need further research before it can be recommended as an adjunct in controlling postoperative pain.
-
Randomized Controlled Trial Clinical Trial
Combined spinal-epidural anesthesia for outpatient surgery. Dose-response characteristics of intrathecal isobaric lidocaine using a 27-gauge Whitacre spinal needle.
Combined spinal-epidural anesthesia (CSE) may offer theoretic advantages for outpatient surgery, because it produces the rapid onset of spinal anesthesia, with the option to extend the blockade with an epidural catheter. In this study, the authors attempted to determine an appropriate initial dose of a short-acting local anesthetic, 2% lidocaine, to administer for outpatient knee arthroscopy using CSE. ⋯ Combined spinal-epidural anesthesia with a 40-mg initial intrathecal dose of lidocaine provided reliable anesthesia for knee arthroscopy. Duration of spinal anesthesia with lidocaine was dose related.