[Remifentanil with propofol or isoflurane. A comparison of the recovery times after arthroscopic surgery]

Remifentanil-propofol in vertebral disk operations: hemodynamics and recovery versus desflurane-n(2)o inhalation anesthesia

The purpose of this study was to ascertain whether total intravenous anesthesia (TIVA) with propofol and remifentanil differs from inhalational anesthesia with desflurane and nitrous oxide in terms of hemodynamics, recovery profile, and postoperative analgesic demand in patients undergoing elective microsurgical vertebral disk resection. A total of 60 patients were randomly assigned to receive TIVA with propofol and remifentanil or inhalational anesthesia with desflurane and nitrous oxide. The TIVA group (n=30) then received 50%/50% N(2)O/O(2). A constant infusion of remifentanil was provided at 0.125 microg/kg/min accompanied by propofol at 10 mg/kg/h in the first 10 min, 6 mg/kg/h in the second 10 min, then 4 mg/kg/h. The desflurane group (n=30) received 50%/50% N(2)O/O(2), with 5% desflurane after intubation and 6% before incision; desflurane was administered in a minimum alveolar concentration 1 fashion during the operation. Hemodynamic, O(2) saturation, and end-tidal CO(2) data were recorded before induction, after intubation, after prone positioning, 5, 10, 15, 20, and 30 min into the operation, and at 15-min intervals thereafter until the end of the operation. Details on perioperative bradycardia, hypotension or hypertension, spontaneous breathing, extubation, eye opening, recovery time of ability to give name and date of birth, postoperative nausea and vomiting, shivering, agitation, and hypoxia were recorded. Patients anesthetized with desflurane responded to skin incision with increasing blood pressure and tachycardia; however, no other hemodynamic differences were noted between the 2 groups. In the TIVA group, recovery times were shorter for spontaneous ventilation (2.33-3.53 min), extubation (3.13-3.88 min), eye opening (4.06-6.23 min), and being able to give name and date of birth (5.4-7.9 min) compared with times in the desflurane group (P<.05). In the TIVA group, more postoperative shivering (16.7% of patients) and greater analgesic demand were seen than in the desflurane group. Although nausea and vomiting were more common in the desflurane group, no difference in bronchospasm was reported. In the TIVA group, a shorter recovery period and a greater demand for postoperative analgesia were seen. Because of the lack of residual analgesic effects, postoperative analgesic treatment should be initiated immediately in patients undergoing TIVA.

Intraoperative Wake-Up Test and Postoperative Emergence in Patients Undergoing Spinal Surgery: A Comparison of Intravenous and Inhaled Anesthetic Techniques Using Short-Acting Anesthetics

Surgical procedures on the vertebral column may result in spinal cord damage, leading to neurological deficits that demand immediate therapeutical intervention. We designed this study to determine which anesthetic regimen allows a rapid wake-up test during and after surgery to detect neurological deficits. Fifty-four patients were randomly allocated to the following groups: group PR (propofol/remifentanil): target-controlled infusion with propofol (plasma concentration, 2-4 microg/mL) and remifentanil 0.2-0.5 microg . kg(-1) . min(-1); group PS (propofol/sufentanil): propofol (2-4 microg/mL) and repetitive boluses of 0.1-0.2 microg/kg of sufentanil adjusted to patients requirements; and group DR (desflurane/remifentanil): desflurane/air 3.0-4.0 vol% combined with remifentanil 0.2-0.5 microg . kg(-1) . min(-1). Group PS required significantly longer times for the onset of breathing (8.9 +/- 1.6 min), elevation of the head (17.0 +/- 3.8 min), and motion of the feet (17.0 +/- 7.4 min) than group PR (6.9 +/- 2.6 min, 9.3 +/- 2.2 min, and 9.4 +/- 2.4 min, respectively) or group DR (5.4 +/- 0.8 min, 6.1 +/- 1.0 min, and 6.2 +/- 1.0 min, respectively). The anesthetic regimen with desflurane and remifentanil allowed faster awakening during and after surgery that permitted immediate neurological examination after spinal surgery compared with propofol/remifentanil.

Prospective, randomized cost analysis of anesthesia with remifentanil combined with propofol, desflurane or sevoflurane for otorhinolaryngeal surgery

BACKGROUND

In the era of cost containment, cost analysis should demonstrate the cost-effectiveness of new anesthetic drugs.

METHODS

This single-blind, prospective, randomized study compared the costs of three remifentanil (REM)-based anesthetic techniques with a conventional one in 120 patients undergoing otorhinolaryngeal surgery. The patients were randomized (n=30 each group) to either receive a combination of REM with propofol, desflurane or sevoflurane, or a conventional anesthetic with thiopentone, alfentanil, isoflurane and N2O.

RESULTS

The costs for anesthetic and nonanesthetic drugs and for disposables were twice as high in the three REM-based groups as in the conventional group (REM/PRO 0.51 Euro;/min, REM/DES 0.42 Euro;/min, and REM/SEVO 0.41 Euro;/min vs. 0.18 Euro;/min in the ALF/ISO/N2O group; P<0.05). Wastage of intravenous drugs accounted for up to 40% of total costs. In all REM groups, early recovery was predictably faster and more complete (P<0.05). Patient satisfaction was equally high (90-97%) in all groups, with less nausea in the REM/PRO group.

CONCLUSION

This study demonstrates that REM-based anesthetic techniques are more expensive than a conventional technique using alfentanil, isoflurane and N2O. This is the result of higher costs of anesthetic and nonanesthetic drugs and of disposables. The wastage of intravenous drugs contributes considerably to these costs.

Intraoperative awareness: detected by the structured Brice interview?

BACKGROUND

Awareness is a rare complication in general anesthesia, but its consequences are stressful. Efforts must be undertaken to prevent, diagnose, and, if occurring, treat it. The incidence of awareness is higher following anesthesia involving the use of muscle relaxants. As a part of a quality assurance program at our short-stay surgery all patients exposed to general anesthesia are routinely subjected to a Brice interview, which aims to evaluate our standard anesthetic technique regarding awareness.

METHODS

The Brice interview was used prospectively in 5216 patients given a propofol/opioid anesthetic for day-case or short-stay surgery. Neuromuscular blocks were used only for surgical needs, not routinely. All patients were interviewed on discharge from the recovery room. A second interview, according to Brice, was undertaken by telephone 3-7 days later in the case of a notable intraoperative event, or otherwise after postoperative patient complaints. All patients were also interviewed by telephone 1-2 days postoperatively.

RESULTS

None of the patient interviews indicated awareness. This was also the case in five non-relaxed patients who had an incident of light anesthesia with eye opening and gross motor response without forewarning. Neuromuscular blockade was used in 7% of patients.

DISCUSSION

We were unable to detect intraoperative awareness. The anesthetic regimen, including minimal use of muscle relaxants, might be beneficial for awareness prevention. Alternatively, the diagnostic power, the timing of the Brice interview, or the number of interviews performed may be questioned.

The effect of remifentanil on the heat pain threshold in volunteers

Remifentanil offers a wide range of clinical uses and has been successfully combined with general anesthetics. However, there are few human experimental studies demonstrating the analgesic property of remifentanil. It was our aim to determine the analgesic effect of remifentanil with regard to dose-dependent increments in a human model of heat pain threshold assessment. Twenty healthy volunteers were randomized in a double-blinded cross-over design to receive an infusion of remifentanil or saline. The stepped infusion was increased every 5 min by 0.01 microg. kg(-1). min(-1) up to 0.17 microg. kg(-1). min(-1)and terminated in case of defined safety limits. Thermal sensory testing of the heat pain threshold was performed every 5 min at the left forearm. The dose-response relationship and the effective dose for at least 50% of the subjects (ED(50)) were determined. Remifentanil led to a clear dose-dependent increase of the heat pain threshold differing significantly from placebo (P < 0.0007). The ED(50) of remifentanil equals 0.05 microg. kg(-1). min(-1) (first quartile 0.025 microg. kg(-1). min(-1) and third quartile 0.06 microg. kg(-1). min(-1)) in this experimental setting. In conclusion, an opioid-mediated analgesic effect of remifentanil was determined in a human heat pain threshold model. The dose of 0.05 microg. kg(-1). min(-1) is an effective and safe increment in healthy volunteers.

The use of esmolol as an alternative to remifentanil during desflurane anesthesia for fast-track outpatient gynecologic laparoscopic surgery

We compared esmolol and remifentanil infusions with respect to their effect on intraoperative hemodynamic stability and early recovery after outpatient laparoscopic surgery when administered as IV adjuvants during desflurane anesthesia. After premedication with midazolam 2 mg IV, anesthesia was induced with propofol 2 mg. kg(-1) IV in combination with either esmolol 1 mg. kg(-1) IV (n = 27) or remifentanil 1 microg. kg(-1) IV (n = 26) and succinylcholine 1 mg. kg(-1) IV according to a randomized, double-blinded protocol. Anesthesia was initially maintained with desflurane 2.5% (subsequently titrated to maintain an electroencephalogram-bispectral index value of 60) and nitrous oxide 65% in oxygen. Before skin incision, an infusion of either esmolol (5 microg. kg(-1). min(-1)) or remifentanil (0.05 microg. kg(-1). min(-1)) was started and titrated to maintain the heart rate within 25% of the baseline value. Mivacurium, 0.04 mg/kg IV, bolus doses were administered to maintain a stable peak inspiratory pressure. Esmolol (12.8 +/- 13.1 microg. kg(-1). min(-1)) and remifentanil (0.04 +/- 0.02 microg. kg(-1). min(-1)) infusions were equally effective in maintaining a stable heart rate during these laparoscopic procedures. Although the mivacurium requirement was larger in the Esmolol group (7 +/- 5 vs 3 +/- 4 mg), the Esmolol group reported a smaller incidence of postoperative nausea and vomiting (4% vs 35%). Both drugs were associated with frequent "postanesthesia care unit bypass" rates (78-81%), short times to "home readiness" (119-120 min), excellent patient satisfaction (81-85%), and rapid resumption of normal activities (2.6-3.2 d). Fast-tracked patients were ready for discharge home significantly earlier (112 +/- 46 vs 151 +/- 50 min). We concluded that esmolol infusion is an acceptable alternative to remifentanil infusion for maintaining hemodynamic stability during desflurane-based fast-track anesthesia for outpatient gynecologic laparoscopic surgery.

Recovery of cognitive function after remifentanil-propofol anesthesia: a comparison with desflurane and sevoflurane anesthesia

We compared the recovery characteristics of remifentanil, desflurane, and sevoflurane when used for anesthesia in elective operative procedures. Sixty ASA physical status I and II patients, aged 18-65 yr, were randomly assigned to receive remifentanil-propofol, desflurane-N2O, or sevoflurane-N2O anesthesia. Before the induction of anesthesia, the patients of the desflurane and sevoflurane groups received fentanyl 2 microg/kg. In all groups, anesthesia was induced with propofol and maintained either with remifentanil 0.25 microg x kg(-1) x min(-1), desflurane, or sevoflurane 0.85 MAC with 65% nitrous oxide in oxygen. Anesthetics were titrated to achieve an adequate level of surgical anesthesia and to maintain mean arterial pressure within 20% of baseline values. Early recovery times and a modified Aldrete Recovery Score > 9 were recorded. Trieger Dot Test and Digit Substitution Test (DSST) were performed the day before surgery and in the postanesthesia care unit to evaluate intermediate recovery. The remifentanil-propofol group had a significantly faster emergence than desflurane or sevoflurane, with no difference between both inhaled anesthetics. Thirty min after anesthesia administration, patients in the remifentanil-propofol and in the desflurane groups gave significantly more correct responses in the DSST compared with sevoflurane (remifentanil 87%, desflurane 83%, sevoflurane 56%), the impairment in the sevoflurane patients corresponding to the effects of a blood alcohol level of approximately 0.1% and, thus, being of clinical importance. Ninety minutes after anesthesia administration, no significant difference could be demonstrated among the groups in the DSST scores. Emergence and return of cognitive function was significantly faster after remifentanil-propofol compared with desflurane and sevoflurane up to 60 min after anesthesia administration.

IMPLICATIONS

We compared awakening and intermediate recovery times after remifentanil-propofol anesthesia to desflurane-N2O and sevoflurane-N2O anesthesia. Emergence and return of cognitive function was significantly faster after remifentanil-propofol compared with desflurane and sevoflurane up to 60 min after anesthesia administration.

Remifentanil as an adjuvant during desflurane anesthesia facilitates early recovery after ambulatory surgery

STUDY OBJECTIVE

To investigate the effect of using a remifentanil infusion during desflurane anesthesia on the early recovery profile and side effects.

DESIGN

Randomized, single-blind study.

SETTING

University-based ambulatory surgery unit.

PATIENTS

46 healthy, ASA physical status I and II women undergoing outpatient laparoscopic tubal ligation procedures.

INTERVENTIONS

After premedication with midazolam 2 mg intravenously (IV), anesthesia was induced with propofol 2 mg.kg-1 i.v. and remifentanil 1 microgram.kg-1 i.v. Following tracheal intubation, anesthesia was maintained with desflurane 2% and nitrous oxide (N2O) 65% in both groups. During the maintenance period, hemodynamic stability was maintained using either a variable inspired concentration of desflurane, 2% to 8% (Control group), or a variable-rate infusion of remifentanil 0.05 to 0.2 microgram.kg-1.min-1 i.v. (Remi group). Ketorolac 30 mg i.v. and local anesthetic infiltration at the surgical portals were administered for preventive analgesia prior to skin closure.

MEASUREMENTS AND MAIN RESULTS

Emergence times and times to achieving an Aldrete score of 10 (i.e., fast-tracking eligibility) were determined. Postoperative nausea and vomiting (PONV), as well as the need for analgesic and antiemetic rescue medications, were noted during the 24-hour follow-up period. A structural questionnaire was used to assess intraoperative recall. Compared to the Control group, the Remi group had shorter emergence times and reduced times to achieving an Aldrete score of 10. There were no differences between the two groups with respect to the incidence of PONV and the requirements for postoperative analgesic and antiemetic drugs. None of the patients experienced intraoperative recall.

CONCLUSIONS

The adjunctive use of a remifentanil infusion (0.07 +/- 0.03 microgram.kg-1.min-1) during desflurane-N2O anesthesia facilitated early recovery without increasing PONV, pain, or the need for rescue medication after laparoscopic surgery.

Total intravenous anaesthesia with propofol and remifentanil in paediatric patients: a comparison with a desflurane-nitrous oxide inhalation anaesthesia

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.