Anesthesia Recovery Period

Midazolam and alfentanil were infused in a totally i.v. anesthetic technique (TIVA) to patients undergoing hysterectomy. Correlations of midazolam plasma concentrations and effects were made during recovery. Due to the high doses of midazolam administered during TIVA, metabolism and not redistribution mainly governed the duration of effects post-infusion. The concomitant administration of alfentanil contributed to the sedative effect, as illustrated by a shift of the concentration-response curve to the left. As a result of these effects, recovery was prolonged and extended over 2-6 h.

We studied 94 healthy ASA physical status I or II children to determine the end-expired concentration of halothane associated with eye opening on emergence from anesthesia, and to determine if parenteral opioid therapy or regional analgesia significantly altered this concentration. In our study, anesthesia was maintained with halothane in an air-oxygen mixture. After the surgical procedure was completed, the inspired concentration of halothane was adjusted to zero and the end-expired concentrations were permitted to decrease spontaneously.

In a randomized, double-blind study, we administered placebo and flumazenil to 40 healthy Chinese boys, aged 3-12 yr, undergoing circumcision. The children received midazolam 0.5 mg kg-1 orally for premedication and 0.5 mg kg-1 i.v. during induction. After operation the patients were given 0.1 ml kg-1 of a blinded solution followed by 0.05 ml kg-1 min-1 until either they awoke or the 10-ml ampoule of solution was empty.

To evaluate the concentration-effect relationships of propofol during recovery after total intravenous anesthesia, 20 female patients undergoing lower abdominal surgery were studied. In 10 patients (Group B) the propofol infusion was supplemented with an epidural block with bupivacaine to evaluate the relation between the blood concentration of propofol and various pharmacodynamic end-points. The remaining 10 patients (Group A) received an alfentanil infusion intravenously instead of the epidural block to assess the dynamic interactions of alfentanil and propofol.

Hypnosis combined with chemical sedation is uncommonly utilized by physicians, however, the combination of hypnosis and sedation can be an effective modality in the management of uncooperative pedodontic patients. In order to examine the efficacy of this combination technique, we selected 13 pedodontic patients for Ketamine sedation combined with hypnosis. The patients ranged from four to 11 years of age, and all had previous histories of violent emotional reactions before and after dental treatment.

BACKGROUND: The aim of this study is to control the depth, the quality of recovery of total inhalation isoflurane anesthesia with or without nitrous oxide. DESIGN: Controlled comparative study was carried out on 51 patients, aged 40-54 yr, ASA 1, undergoing saphenectomy, in an University Clinic. METHODS: Induction: thiopental (3.5 mg kg), atracurium (0.6 mg kg) i.v. Patients were randomly assigned to: group 1 (26 patients), 5% isoflurane in air, by mask; group 2 (25 patients), 3% isoflurane and 60% N2O, by mask.

OBJECTIVE: To compare the hemodynamic stability and time to recovery of consciousness after long-duration (> 3 h) neurosurgery with 2 anesthetic protocols: total intravenous anesthesia with propofol as the single hypnotic agent and inhalational anesthesia with isoflurane. PATIENTS AND METHOD: We studied 58 middle-aged patients (range 40-50 years) scheduled for intracranial surgery. The patients, who all scored over 13 on the Glasgow coma scale before surgery, were randomly divided into two groups: 27 in group I received isoflurane and 31 in group II received propofol.

Most previous studies which have assessed the depth of anaesthesia using the Bispectral Index (BIS) have used multi-agent anaesthetics with relatively slow induction and recovery times. Elevation of electroencephalographic (EEG) Beta/Alpha Ratio has been linked to onset of midazolam amnesia. Propofol anaesthesia for cardioversion in 19 patients enabled us to profile the changes in BIS and Beta/Alpha Ratio during a short, single-agent anaesthetic with a relatively rapid induction and recovery period.

The bispectral index (BIS) is derived empirically from the electroencephalogram database of patients receiving common anaesthetics, but it may not be valid for uncommon agents. Therefore, we investigated how xenon affects the BIS. Nine and 11 patients were anaesthetized with 0.8 of the minimal alveolar concentration (MAC) of isoflurane (0.92%) and xenon (56%), respectively. After the end of operation, these concentrations were decreased in decrements of 0.1 MAC (isoflurane 0.12% or xenon 7%) and each new concentration was maintained for 15 min.

We evaluated the cognitive recovery profiles in elderly patients after general anesthesia with desflurane or sevoflurane. After IRB approval, 70 ASA physical status I-III consenting elderly patients (> or =65 yr old) undergoing total knee or hip replacement procedures were randomly assigned to one of two general anesthetic groups. Propofol and fentanyl were administered for induction of anesthesia, followed by either desflurane 2%-4% or sevoflurane 1%-1.5% with nitrous oxide 65% in oxygen. The desflurane (2.5 +/- 0.6 MAC. h) and sevoflurane (2.7 +/- 0.5 MAC.