Anesthesia and analgesia
-
Anesthesia and analgesia · Mar 2005
Randomized Controlled Trial Clinical TrialAirway reflexes return more rapidly after desflurane anesthesia than after sevoflurane anesthesia.
Patients given a more soluble inhaled anesthetic usually take longer to awaken from anesthesia than do patients given a less soluble anesthetic. In the present study, we tested whether such a delay in awakening was also associated with a delay in restoration of protective airway reflexes. Patients were randomly assigned to receive desflurane (n = 31) or sevoflurane (n = 33) via a laryngeal mask airway. ⋯ At 2 min after responding to command, all patients given desflurane were able to swallow without coughing or drooling, whereas 55% of patients given sevoflurane coughed and/or drooled (P < 0.001). At 6 min after responding to command, 18% of patients given sevoflurane still could not swallow without coughing or drooling (P < 0.05). We conclude that desflurane allows an earlier return of protective airway reflexes.
-
Anesthesia and analgesia · Mar 2005
Randomized Controlled Trial Clinical TrialEpidural ropivacaine anesthesia decreases the bispectral index during the awake phase and sevoflurane general anesthesia.
The sedative effects of epidural anesthesia without volatile and IV anesthetics and quantification of the degree of epidural anesthesia-induced sedation have not been investigated. In the current study we evaluated the effects of epidural anesthesia on the bispectral index (BIS) during the awake phase and during general anesthesia. After placing the epidural catheter, the patients were randomly allocated to 2 groups receiving either 5 mL of epidural saline (group S) or the same volume of 0.75% ropivacaine (group R). ⋯ The BIS during general anesthesia was significantly lower in group R than in group S (P < 0.0001). Epidural anesthesia decreased the BIS during the awake phase and during general anesthesia. The decrease of the BIS associated with epidural anesthesia was more prominent during general anesthesia than during the awake phase.
-
Anesthesia and analgesia · Mar 2005
Threshold current of an insulated needle in the intrathecal space in pediatric patients.
A threshold current of <1 mA has been suggested to be sufficient to produce a motor response to electrical stimulation in the intrathecal space. We designed this study to determine the threshold current needed to elicit motor activity for an insulated needle in the intrathecal space. Twenty pediatric patients aged 7.3 +/- 3.9 yr scheduled for lumbar puncture were recruited. ⋯ In 19 patients, the twitches were observed at the L4-5 myotomes and 1 patient had twitches at L2. Twitches were observed unilaterally in 19 children and bilaterally in one child. This confirms the hypothesis that the threshold current in the intrathecal space is <1 mA and that it differs significantly from the threshold currents reported for electrical stimulation in the epidural space.
-
Anesthesia and analgesia · Mar 2005
The effects of propofol or sevoflurane on the estimated cerebral perfusion pressure and zero flow pressure.
The zero flow pressure (ZFP) is the pressure at which blood flow ceases through a vascular bed. Using transcranial Doppler ultrasonography, we investigated the effects of propofol or sevoflurane on the estimated cerebral perfusion pressure (eCPP) and ZFP in the cerebral circulation. Twenty-three healthy patients undergoing nonneurosurgical procedures under general anesthesia were studied. ⋯ The eCPP decreased significantly in the propofol group (median, from 58 to 41 mm Hg) but not in the sevoflurane group (from 60 to 62 mm Hg). Correspondingly, ZFP increased significantly in the propofol group (from 25 to 33 mm Hg) and it decreased significantly in the sevoflurane group (from 27 to 7 mm Hg). Hypocapnia did not change eCPP or ZFP in the propofol group, but it significantly decreased eCPP and increased ZFP in the sevoflurane group.
-
Intraoperative blood salvage (IBS) devices are used as adjuncts to blood conservation in spinal surgical procedures of increasing duration, complexity, and total blood loss. We applied existing information about the performance and efficiency of IBS devices together with existing information regarding the distribution of crystalloids and colloids to provide clinicians with guidelines for the prediction of the total blood loss implications of a given volume of IBS return. ⋯ When replacement is undertaken with colloids or crystalloids, the appropriate replacement volume will be approximately 2.5 and 8.0 (respectively) times the volume of the IBS recovery. These volumes may be larger than have been appreciated by some clinicians.