Acta anaesthesiologica Scandinavica
-
Acta Anaesthesiol Scand · Jan 2005
Randomized Controlled Trial Comparative Study Clinical TrialSevoflurane induces less cerebral vasodilation than isoflurane at the same A-line autoregressive index level.
The use of sevoflurane in neuroanesthesia is still under debate. Comparison of dose-dependent vasodilatory properties between sevoflurane and isoflurane, the more traditional neuroanesthetic agent, requires comparable dosing of the agents. A-line autoregressive index (AAI) provides reproducible individual measurement of anesthetic depth. ⋯ Sevoflurane induced less cerebral vasodilation than isoflurane at the same depth of anesthesia, measured by AAI, and hence seems more favorable for clinical neuroanesthesia. In our opinion the difference between sevoflurane and isoflurane in the MAC fraction required to attain the same AAI level demonstrates the limitations of MAC in defining the level of anesthesia.
-
Acta Anaesthesiol Scand · Jan 2005
Randomized Controlled Trial Comparative Study Clinical TrialCerebral blood flow velocity increases when propofol is changed to desflurane, but not when isoflurane is changed to desflurane in children.
Children may exhibit delayed emergence following maintenance of anesthesia with propofol or isoflurane. Desflurane is often used towards the end of procedures to facilitate emergence. This study evaluated the effect on middle cerebral artery blood flow velocity (Vmca) in anesthetized children when propofol or isoflurane was substituted with desflurane. ⋯ When propofol is changed to desflurane, cerebral blood flow velocity increases significantly in normal children. This cerebral vasodilatory effect may have important implications in the neurosurgical setting.
-
Acta Anaesthesiol Scand · Jan 2005
Randomized Controlled Trial Clinical TrialInfluence of the injection site (L2/3 or L3/4) and the posture of the vertebral column on selective spinal anesthesia for ambulatory knee arthroscopy.
We tested the hypothesis that selective spinal anesthesia for ambulatory knee arthroscopy can be accomplished with a small dose of bupivacaine at the L3/4 interspace with or without a head-down tilt of 5 degrees when the patients were in the lateral decubitus position. ⋯ When producing selective spinal anesthesia, the posture of the vertebral column is a major determinant of both sensory and motor segments to be blocked. A 4-mg dose of hyperbaric bupivacaine at the L3/4 interspace with a 5 degrees head-down tilt of the vertebral column for 6 min is recommended for knee arthroscopy.
-
Acta Anaesthesiol Scand · Jan 2005
Randomized Controlled Trial Clinical TrialThermogenic effect of amino acids not demonstrated in heart surgery with cardiopulmonary bypass.
In abdominal surgery and in healthy volunteers, amino acids increased thermogenesis. In this double-blind study we investigated if a similar effect would ensue in heart surgery and accelerate the rewarming process postoperatively. ⋯ The lack of a thermal effect of the amino acids in the heart surgery was most probably due to the temperature gradients between the different body compartments, and also may have been due to the use of beta-blockers.
-
Acta Anaesthesiol Scand · Jan 2005
Randomized Controlled Trial Clinical TrialContinuous physostigmine combined with morphine-based patient-controlled analgesia in the postoperative period.
Recently, new drugs and techniques for the treatment of postoperative pain were introduced, with the goal of enhancing opiates' analgesia while minimizing their side-effects. Cholinergic agents play an antinociceptive role, but their clinical use is quite limited, due to side-effects. Physostigmine is a cholinesterase inhibitor, which crosses the blood-brain barrier and elevates brain acetylcholine level. Physostigmine can produce analgesia by itself, and enhance opiate analgesia; but these effects are of short duration following bolus administration. ⋯ Physostigmine combined with morphine in the postoperative period reduced morphine consumption, enhanced analgesia, and attenuated production of the proinflammatory cytokine, IL-1beta. This latter finding may account for the decreased pain observed in this group; this cytokine is known to mediate basal pain sensitivity and induce hyperalgesia in inflammatory conditions. Taking into account the other potential beneficial effects of physostigmine, we suggest that a continuous infusion of physostigmine should be considered as a useful component in multimodal postoperative analgesia.