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Introduction: After neurosurgery patients often need to be sedated and ventilated in the intensive care unit (ICU). However, rapid postoperative recovery and neurological examination are particularly important for the early recognition of complications. In this retrospective study two different strategies of anaesthesia technique and ICU sedation (fentanyl-midazolam versus remifentanil-propofol) were compared., Methods: Intraoperatively, patients received continuous infusions of either fentanyl (0.2-1.0 mg/h) and midazolam (2-10 mg/h) or remifentanil (0.2-0.5 microg/kg body weight/min) and propofol (3-6 mg/kg body weight/h). After arrival in the ICU fentanyl (0.03-0.2 mg/h) and midazolam (2-12 mg/h) or remifentanil (0.1-0.2 microg/kg body weight/min) and propofol (0.5-3 mg/kg body weight/h) were infused to reach a Ramsay score of 4. The times between termination of infusion and extubation and the length of stay in the ICU were examined., Results: A total of 60 patients (n=30 each group) undergoing supratentorial brain tumour surgery were enrolled. The groups were comparable for age, weight, ASA status (American Society of Anesthesiologists) and duration of drug administration (remifentanil-propofol 528+/-382 min versus fentanyl-midazolam 548+/-360 min). Extubation times were significantly shorter after remifentanil-propofol (47 min) than after fentanyl-midazolam (481 min), and the length of stay in the ICU was also significantly reduced (1.8 days versus 3.7 days). As a result of prolonged unconsciousness and impaired neurological assessability, a brain CT scan was necessary in 3 patients after fentanyl-midazolam to exclude neurosurgical complications., Conclusion: This retrospective study demonstrates that remifentanil-propofol anaesthesia and ICU sedation are superior to the combination of fentanyl and midazolam in terms of ventilation time and length of ICU stay. Moreover, the use of fentanyl-midazolam may lead to unnecessary CT scans.

There is an ongoing debate as to whether propofol exhibits pro- or anticonvulsant effects, and whether it should be used in patients with epilepsy. We prospectively assessed the occurrence of seizure-like phenomena and the effects of intravenous propofol on the electroencephalogram (EEG) in 25 children with epilepsy (mean (SD) age: 101 (49) months) and 25 children with learning difficulties (mean (SD) age: 52 (40) months) undergoing elective sedation for MRI studies of the brain. No child demonstrated seizure-like phenomena of epileptic origin during and after propofol sedation. Immediately after stopping propofol, characteristic EEG changes in the epilepsy group consisted of increased beta wave activity (23/25 children), and suppression of pre-existing theta rhythms (11/16 children). In addition, 16 of 18 children with epilepsy and documented EEG seizure activity demonstrated suppression of spike-wave patterns after propofol sedation. In all 25 children with learning difficulties an increase in beta wave activity was seen. Suppression of theta rhythms occurred in 11 of 12 children at the end of the MRI study. In no child of either group was a primary occurrence or an increase in spike-wave patterns seen following propofol administration. The occurrence of beta wave activity (children with learning difficulties and epilepsy group) and suppression of spike-wave patterns (epilepsy group) were transient, and disappeared after 4 h. This study demonstrates characteristic, time-dependent EEG patterns induced by propofol in children with epilepsy and learning difficulties. Our data support the concept of propofol being a sedative-hypnotic agent with anticonvulsant properties as shown by depression of spike-wave patterns in children with epilepsy and by the absence of seizure-like phenomena of epileptic origin.

Unlabelled: The Narcotrend monitor (MonitorTechnik, Bad Bramstedt, Germany) performs an automatic analysis of the electroencephalogram (EEG) during anesthesia based on a visual assessment of the raw EEG. Its newest software version 4.0 includes a dimensionless index that, similar to the bispectral index (BIS), ranges from 100 (awake) to 0. We compared the performance of Narcotrend index and BIS as EEG measures of anesthetic drug effect during propofol anesthesia. Eighteen adult patients scheduled for radical prostatectomy were investigated. An epidural catheter was placed in the lumbar space and electrodes for BIS (version XP; Aspect Medical Systems, Natick, MA) and Narcotrend were positioned as recommended by the manufacturers. Narcotrend index, BIS values, and propofol plasma and effect site concentrations as parallelly simulated by Rugloop software (Department of Anesthesia, Ghent University, Belgium) were automatically recorded in intervals of 5 s. Induction of anesthesia consisted of a fentanyl bolus and a propofol infusion. After endotracheal intubation, patients received 15 mL bupivacaine 0.5% epidurally, and 45 min later propofol dosages were subsequently increased and decreased twice. Simulated propofol effect site concentrations ranged from 2.0 +/- 0.4 microg/mL (smallest) to 6.3 +/- 1.3 microg/mL (largest) during these subsequent increases and decreases of propofol. In terms of prediction probability (P(K)) the performance of the Narcotrend index (P(K) = 0.88 +/- 0.03) to predict propofol effect site concentrations was comparable to the BIS (P(K) = 0.85 +/- 0.04). Using the respective EEG index as a measure of drug effect the mean k(e0) was calculated as 0.20 +/- 0.05 min(-1) for Narcotrend index and 0.16 +/- 0.07 min(-1) for BIS. In the observed propofol concentration range Narcotrend index detected differences in EEG dynamics as well as BIS., Implications: This study in 18 adult patients undergoing radical prostatectomy describes the relationship between Narcotrend index and bispectral index versus predicted propofol effect compartment concentrations. In terms of prediction probability, the performance of the Narcotrend index and the bispectral index to predict propofol effect site concentrations was comparable.

Background: Nitrous oxide (N2O) has been suggested to contribute to bowel distension, resulting in worsened operating conditions for laparoscopic surgery, and to increase incidence of postoperative nausea and vomiting. Therefore, our objective was to assess the feasibility of two remifentanil-based anaesthetic regimens free from N2O with special regard to recovery profile, postoperative analgesic demand and side effects in patients undergoing laparoscopic cholecystectomy., Methods: Fifty patients (ASA I-II, 23-65 yr) were randomly assigned to receive remifentanil-based anaesthesia in conjunction with propofol (group R/P) or desflurane (group R/D). After standardised induction of anaesthesia, analgesia was continued with remifentanil in all patients. For maintenance of hypnosis, propofol or desflurane were used in concentrations to ensure loss of consciousness, lack of awareness, and maintenance of heart rate and blood pressure within +/- 25% of initial values. At the end of surgery all anaesthetics were discontinued without tapering and early emergence and recovery were recorded. Pain scores were assessed by using a visual analogue scale. Patient-controlled analgesia with i.v. piritramide was used for treatment of postoperative pain and recorded for 90 min in the postanaesthesia care unit (PACU). In addition, side effects were noted., Results: Early emergence from anaesthesia did not differ between the groups. In group R/P, time to eye opening, spontaneous respiration and extubation was 4.4 +/- 2.9 min, 5.2 +/- 3.4 min and 5.5 +/- 3.3 min respectively, compared with 4.7 +/- 2.7 min, 5.3 +/- 2.4 min and 5.7 +/- 2.5 min in group R/D. While pain scores did not differ between both groups on admission to the PACU, patients receiving desflurane required more i.v. piritramide as compared to those receiving propofol, 22.0 +/- 6.5 mg and 17.9 +/- 7.0 mg, respectively (P<0.05). Nausea was less frequent after propofol (16% vs. 48%, P<0.05)., Conclusion: In patients undergoing laparoscopic cholecystectomy, remifentanil-based anaesthetic regimens in conjunction with propofol or desflurane are suitable and allow for rapid recovery from anaesthesia. However, the use of propofol results in less postoperative analgesic consumption and nausea as compared to desflurane.

Study Objective: To compare recovery, hemodynamics, and side effects of remifentanil-based anesthesia with hypnotic concentrations of isoflurane or propofol., Design: Multicenter, prospective, randomized, two-group study., Setting: 15 university and 5 municipal hospitals., Patients: 249 ASA physical status I, II, and III adult patients scheduled for elective gynecological laparoscopy, varicose vein, or arthroscopic surgery of at least 30 minutes' duration., Interventions: Anesthesia was induced in the same manner in both groups: remifentanil-bolus (1 microg/kg), start of remifentanil-infusion (0. 5 microg/kg/min), followed by propofol as needed for induction. Five minutes after intubation, remifentanil was reduced to 0.25 microg/kg/min, and it was combined with either a propofol-infusion (0.1 mg/kg/min) or with isoflurane (0.6 vol% end-tidal) in O(2)/air. Adverse hemodynamic responses of heart rate and systolic blood pressure were recorded and treated according to a predefined protocol. With termination of surgery, anesthetic delivery was discontinued simultaneously without tapering, and recovery times were recorded., Measurements and Main Results: No significant differences were observed between the remifentanil-isoflurane or remifentanil-propofol treatment regimens. Recovery times (means +/- SD) were similar for spontaneous ventilation (5.8 +/- 3.2 min vs. 6. 3 +/- 3.7 min), extubation (7.6 +/- 3.5 vs. 8.5 +/- 4.2 min), eye opening (6.8 +/- 3.2 vs. 7.5 +/- 3.8 min), and arrival to the postanesthesia care unit (16.5 +/- 7.0 vs.18.0 +/- 7.2 min). There were no significant differences in adverse hemodynamic responses, postoperative shivering, nausea, or vomiting between the groups., Conclusions: Emergence after remifentanil-based anesthesia with 0.6 vol% of isoflurane is at least as rapid as with 0.1 mg/kg/min propofol. Both isoflurane and propofol are suitable adjuncts to remifentanil, and the applied dosages are clinically equivalent with respect to emergence and recovery. Therefore, both combinations should be appropriate, particularly in settings in which rapid recovery from anesthesia is desirable, such as fast tracking and/or ambulatory surgery.

Background: Remifentanil is a new rapid-acting and ultra-short acting mu-opioid receptor agonist with few reports from use in children. Therefore, we compared a propofol-remifentanil-anaesthesia (TIVA) with a desflurane-N2O-anaesthesia (DN) with particular regard to the recovery of characteristics in children., Methods: 50 children (4-11 yr) scheduled for ENT surgery were randomly assigned to receive TIVA (n = 25) or DN (N = 25). After standardised i.v. induction of anaesthesia in both groups with remifentanil, propofol and cisatracurium, TIVA was maintained with infusion of propofol and remifentanil. Ventilation was with oxygen in air. DN was maintained with desflurane in 50% N20. The administration of volatile and intravenous anaesthetics was adjusted to maintain a surgical plane of anaesthesia. At the end of surgery all anaesthetics were terminated without tapering and early emergence and recovery were assessed. In addition, side effects were noted., Results: Both anaesthesia methods resulted in stable haemodynamics but significantly higher heart rate with desflurane. Recovery did not differ between the groups except for delayed spontaneous respiration after TIVA. Spontaneous ventilation occurred after 11 +/- 03.7 min versus 7.2 +/- 2.8 min (mean +/- SD, TIVA versus DN), extubation after 11 +/- 3.7 min versus 9.4 +/- 2.9 min, eye opening after 11 +/- 3.9 min versus 14 +/- 7.6 min and Aldrete score > or = 9 after 17 +/- 6.8 min versus 17 +/- 7.5 min. Postoperatively, there was a significant higher incidence of agitation in the DN group (80% vs. 44%) but a low incidence (< 10%) of nausea and vomiting in both groups., Conclusion: In children, TIVA with remifentanil and propofol is a well-tolerated anaesthesia method, with a lower peroperative heart rate and less postoperative agitation compared with a desflurane-N2O based anaesthesia.

Objective: To ascertain whether there is a difference between total intravenous anaesthesia with propofol (P) and remifentanil (R) and inhalational anaesthesia with desflurane (D) and nitrous oxide (N) with regard to haemodynamic reactions, recovery profile and postoperative analgesic demand in patients scheduled for elective microsurgical vertebral disc resection., Methods: 50 patients (ASA I-II, 18-65 years) were randomly assigned to receive total intravenous anaesthesia with propofol and remifentanil or inhalational anaesthesia with desflurane and nitrous oxide. After standardised induction of anaesthesia in both groups (1 microgram.kg-1 remifentanil, 1.5 mg.kg-1 propofol 0.1 mg.kg-1 cisatracurium), anaesthesia was maintained in the D/N group with desflurane in 50% N2O. The patients of the P/R group received a constant infusion of 2 mg.kg-1.h-1 propofol and a constant infusion of 0.5 microgram.kg-1.min-1 remifentanil, which was reduced after 15 min by 50%. The administration of desflurane and the infusion of the anaesthetics were adjusted to maintain a surgical depth of anaesthesia. At the end of surgery the anaesthetics were discontinued and early emergence from anaesthesia was assessed by measuring time to spontaneous ventilation (VT > 4 ml/kg), tracheal extubation, opening of the eyes and stating correct name and data of birth. The frequency of analgesics and total demand for analgesics were determined using patient-controlled analgesia and recorded for 2 h postoperatively. In addition the pain level of the patients was measured on a visual analogue scale and the incidence of postoperative shivering, nausea and vomiting was noted., Results: Patients anaesthetised with desflurane responded to tracheal intubation and skin incision with increasing blood pressure and showed higher heart rates than patients anaesthetised with propofol and remifentanil, but there were no other haemodynamic differences between the groups in response to surgical stimuli. There were significantly shorter times to spontaneous ventilation (3.2 vs. 6.3 min), extubation (3.8 vs. 9.5 min), eye opening (3.0 vs. 11.5 min) and giving name and date of birth (4.8 vs. 14.3 min) in patients anaesthetised with remifentanil and propofol than in those receiving desflurane and nitrous oxide. In addition, patients anaesthetised with remifentanil and propofol had a greater incidence of postoperative shivering. There were no significant differences between the two groups in the patients' pain scores, analgesic demand and incidence of nausea and vomiting., Conclusion: Patients anaesthetised with propofol and remifentanil have significantly shorter emergence times than patients anaesthetised with desflurane and nitrous oxide. The low incidence of postoperative pain after microsurgical vertebral disc resections requires no large-scale analgesic therapy, even after total intravenous anaesthesia including remifentanil.

Total intravenous anaesthesia (TIVA) using propofol, gamma-hydroxybutyrate (GHB) or midazolam in combination with sufentanil was investigated in 45 patients undergoing coronary artery bypass grafting (CABG). Anaesthesia was induced with sufentanil, etomidate and pancuronium. After endotracheal intubation, anaesthesia was continued with sufentanil (2 micrograms kg-1 h-1) for all patients. Patients were randomized to receive supplementary propofol (2 mg kg-1 h-1, n = 15), gamma-hydroxybutyrate (20 mg kg-1 h-1, n = 15) or midazolam (0.06 mg kg-1 h-1, n = 15). Haemodynamic measurements were performed after induction and at various times in the pre-bypass period. In the propofol group, a significant decrease in heart rate (HR 12% +/- 3%), cardiac index (CI 23% +/- 4%), mean arterial pressure (MAP 16% +/- 3%) and left ventricular stroke work index (LVSWI 17% +/- 4%) occurred until sternotomy was performed. With the exception of cardiac index, both midazolam and gamma-hydroxybutyrate produced similar haemodynamic effects: cardiac index was temporarily decreased (19% +/- 4%) by midazolam and remained unchanged after gamma-hydroxybutyrate. In both groups, sternotomy was followed by temporary hypertension, associated with a significant rise in systemic vascular resistance. No electrocardiographical signs of ischaemia were observed in any patient. In the case of propofol and midazolam, gamma-hydroxybutyrate showed adequate haemodynamic stability especially after induction of anaesthesia and may also be a suitable agent for total intravenous anaesthesia in patients with coronary artery disease. However, during sternotomy, supplementary administration of opioids was required.

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