The Changing Role of Monitored Anesthesia Care in the Ambulatory Setting

Determining ED90 of Flumazenil for Selective Respiratory Distress Improvement Using Remimazolam During Endoscopic Submucosal Dissection of Gastric Neoplasms: A Prospective Study

BACKGROUND

Patients undergoing endoscopic submucosal dissection under monitored anesthesia care (MAC) with remimazolam may develop respiratory distress during the procedure. In these cases, low doses of flumazenil improved respiratory distress without completely reversing sedation, which is a novel phenomenon. This study aimed to explore the ED90 of flumazenil to selectively improve respiratory distress in patients with MAC treated with remimazolam.

METHODS

Flumazenil dose determination followed a biased-coin up-and-down design. Starting with a dose of 5 mcg, if respiratory distress improved, the biased-coin method was used to give the same dose in the next patient with a probability of 8/9, and a decreased dose of 5 mcg in the next patient with a probability of 1/9. Any improvement in respiratory distress within 30 s of flumazenil administration was recorded. After the procedure, patients were asked whether they had any memory recall during the procedure. Centered isotonic regression was used to determine the ED90 of flumazenil.

RESULTS

Sixty patients were included in the study. The estimated ED90 was 76.72 mcg (95% CI: 68.07-102.62). Memory recall occurred in two of thirteen patients (15%) near the ED90 dose range (75 mcg and 80 mcg). None of the patients developed major postoperative complications (bleeding, perforation, or aspiration) within the 2-day postoperative period.

CONCLUSIONS

This study determined that the ED90 of flumazenil for effectively alleviating respiratory distress in patients undergoing MAC with remimazolam was 76.7 mcg, without reversing consciousness. These findings provide valuable guidance for the care of patients undergoing sedation.

Associations between Clinicopathological Characteristics and Intraoperative Opioid Requirements during Endoscopic Submucosal Dissection with Monitored Anesthesia Care: A Retrospective Study

Background and study aims: Endoscopic submucosal dissection is used to treat early gastric neoplasms. Compared with other endoscopic procedures, it requires higher doses of opioids, leading to adverse events during monitored anesthesia care. We investigated the correlations between clinicopathological characteristics and intraprocedural opioid requirements in patients who underwent endoscopic submucosal dissection under monitored anesthesia care. Patients and methods: The medical records of patients who underwent endoscopic submucosal dissection under monitored anesthesia care were retrospectively reviewed. The dependent variable was the total dose of fentanyl administered during the dissection, while independent variables were patient demographics, the American Society of Anesthesiologists physical status classification, preoperative vital sign data, and the pathological characteristics of the neoplasm. Correlations between variables were examined using multiple regression analysis. Results: The study included 743 patients. The median total fentanyl dose was 100 mcg. Younger age (coefficient -1.37; 95% confidence interval [CI] -1.78 to -0.95), male sex (16.12; 95% CI 6.99-25.24), baseline diastolic blood pressure (0.44; 95% CI 0.04-0.85), neoplasm length (1.63; 95% CI 0.90-2.36), and fibrosis (28.59; 95% CI 17.77-39.42) were positively correlated with the total fentanyl dose. Total fentanyl dose was higher in the differentiated (16.37; 95% CI 6.40-26.35) and undifferentiated cancers group (32.53; 95% CI 16.95-48.11) than in the dysplasia group; no significant differences were observed among the others. The mid-anterior wall (22.69; 95% CI 1.25-44.13), mid-posterior wall (29.65; 95% CI 14.39-44.91), mid-greater curvature (28.77; 95% CI 8.56-48.98), and upper groups (30.06; 95% CI 5.01-55.12) had higher total fentanyl doses than the lower group, whereas doses did not significantly differ for the mid-lesser curvature group. Conclusions: We identified variables that influenced opioid requirements during monitored anesthesia care for endoscopic submucosal dissection. These may help predict the needed opioid doses and identify factors affecting intraprocedural opioid requirements.

Local Anaesthesia Alone Versus Regional or General Anaesthesia in Excisional Haemorrhoidectomy: A Systematic Review and Meta-Analysis

BACKGROUND

Excisional haemorrhoidectomy has been traditionally performed under general or regional anaesthesia. However, these modes are associated with complications such as nausea, urinary retention and motor blockade. Local anaesthesia (LA) alone has been proposed to reduce side effects as well as to expedite ambulatory surgery. This systematic review aims to assess LA versus regional or general anaesthesia for excisional haemorrhoidectomy.

METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. MEDLINE, EMBASE and CENTRAL databases were searched to 13 January 2020. All randomised controlled trials comparing LA only versus regional or general anaesthesia in patients who received excisional haemorrhoidectomy were included. The main outcomes included pain, adverse effects and length of stay.

RESULTS

Nine trials, consisting of six studies comparing local versus regional anaesthesia and three comparing LA versus general anaesthesia, were included. Meta-analysis showed a significantly lower relative risk for need of rescue analgesia (RR 0.32 [95% CI 0.16-0.62]), intra-operative hypotension (RR 0.17 [95% CI 0.04-0.76]), headache (RR 0.13 [0.02-0.67]) and urinary retention (RR 0.17 [95% CI 0.09-0.29]) for LA when compared with regional anaesthesia. There was mixed evidence for both regional and general anaesthesia in regard to post-operative pain.

CONCLUSIONS

LA alone may be considered as an alternative to regional anaesthesia for excisional haemorrhoidectomy with reduced complications and reduction in the amount of post-operative analgesia required. The evidence for LA compared to general anaesthesia for haemorrhoidectomy is low grade and mixed.

The Influence of Adding Diphenhydramine Before Initiation of Moderate Sedation with Midazolam and Pethidine for Improving Quality of Colonoscopy

BACKGROUND

Combination of Intravenous benzodiazepines with opiates appears to be essential in order to guarantee high quality of moderate sedation during colonoscopy. Diphenhydramine is recommended for endoscopic procedures in difficult-to-sedate patients However, the studies supporting its use have yielded conflicting results.

OBJECTIVE

To assess the value of adding diphenhydramine hydrochloride before initiation of moderate sedation with midazolam and pethidine for Improving Quality of Sedation during colonoscopy.

METHODS

We conducted a prospective, randomized, double-blind, placebo-controlled study of 150 Patients undergoing diagnostic colonoscopy. Of 150 patients, data were analyzed for 100 patients randomized into two groups: Diphenhydramine group (n = 53) received 50 mg of diphenhydramine intravenously before initiation of moderate sedation with pethidine and midazolam while in placebo group (n = 47) received placebo in addition to pethidine and midazolam. Amount of pethidine and midazolam used and Quality of sedation were assessed.

RESULTS

The mean doses of pethidine was significantly higher in placebo group as compared to diphenhydramine group (69.9 ± 35.4 mg vs 61.2 ± 21.0 mg, p < 0.01) However, no significant difference between the two groups regarding midazolam mean dose (4.9.±2.1 mg vs 4.8 ± 2.0 mg,p = 0.786). More patients in diphenhydramine group were being very satisfied with the procedure as compared to those in placebo group (88.67% vs 59.57%,p < 0.001).Furthermore more endoscopist in diphenhydramine group were being very satisfied with the procedure as compared to those in placebo group (77.35% vs 51.06%,p < 0.001).

CONCLUSIONS

Intravenous diphenhydramine hydrochloride given before initiation of midazolam and pethidine offers a significant Improvement of Quality of moderate Sedation during colonoscopy without increasing the number of sedation related complications.

Dexmedetomidine and Midazolam Sedation Reduces Unexpected Patient Movement During Dental Surgery Compared With Propofol and Midazolam Sedation

PURPOSE

Owing to its unpredictability, unexpected patient movement is one of the most important problems during surgery while under monitored anesthesia care with sedation. The purpose of this study was to compare unexpected patient movement during dental surgery while under dexmedetomidine and propofol sedation.

MATERIALS AND METHODS

The authors designed and implemented a prospective randomized controlled trial. Patients undergoing dental surgery requiring intravenous sedation were randomly assigned to dexmedetomidine and midazolam (dexmedetomidine group) or propofol and midazolam (propofol group) sedation. In each group, midazolam 0.02 mg/kg was administered in conjunction with continuous administration of dexmedetomidine or propofol to maintain a bispectral index value of 70 to 80. Unexpected patient movement interfering with the procedure was defined as acceptable, defined as no body movement or only 1 controllable movement, or unacceptable, defined as at least 2 controllable movements or any uncontrollable movement. The primary outcome was unexpected patient movement, and the secondary outcome was defined as snoring and cough reflex. Other variables included demographic and procedural characteristics. Continuous or ordinal variables were analyzed using the Student t test or Mann-Whitney test. Dichotomous or categorical variables were analyzed using the χ² test or Fisher exact test. A P value less than.05 was considered statistically significant.

RESULTS

Eighty-eight patients were enrolled in the study (dexmedetomidine group, n = 44; propofol group, n = 44). There were no relevant differences between groups for demographics and baseline variables. Intraoperative unacceptable patient movement occurred more commonly in the propofol group (n = 13; 30%) than in the dexmedetomidine group (n = 4; 9%; P = .015). Intraoperative snoring occurred more commonly in the dexmedetomidine than in the propofol group (P = .045). Incidence and number of cough reflexes were comparable between groups.

CONCLUSION

Dexmedetomidine and midazolam sedation decreases unexpected patient movement during dental surgery compared with propofol and midazolam sedation.

Hysteroscopic polypectomy: a comparison between 22 Fr and 26 Fr resectoscopes under paracervical block anesthesia, a randomized controlled study

Objective: The aim of this study was to compare 22 Fr unipolar resectoscope with the traditional 26 Fr unipolar resectoscope in endometrial polypectomy performed under paracervical block anesthesia. Methods: The trial took place in Gynecologic Unit, Department of Surgery, Tor Vergata University Hospital, Rome. Inclusion criteria were: diagnosis of endometrial polyps <3 cm at office hysteroscopy; agreement of patients to perform surgery under paracervical block anesthesia but not in office setting. Patients with ASA physical status classes III or more and with contraindication to operative hysteroscopy were excluded. Before the procedure, the recruited patients were randomly assigned to two groups, 35 to the 22 Fr unipolar resectoscope group (group A) and 35 to the 26 Fr unipolar resectoscope group (group B). Primary endpoint was the time spent for cervical dilatation and resection. Secondary endpoints were pain during and after surgery, efficacy of paracervical block, use of analgesic drugs during and after the procedure, patients' satisfaction, correlation between pain and menopause or parity. Statistical analysis was performed by the SPSS software, and the tests used were Pearson Chi-Square, One-way ANOVA and Mann-Whitney test. A p value <.05 was considered significant. Results: The mean time for cervical dilatation was two minutes in group A (26 Fr) and five minutes in group B (22 Fr, p = .001). Operative mean time was four minutes in group A and seven minutes in group B (p = .001). Pain during dilatation was analogous (VAS = 6, p = .054), while during the procedure it was higher in group B (VAS = 1 vs VAS = 2, p = .003). Sufentanil was administered during resection in 19 patients of group A and in 22 patients of group B (p = .754). General anesthesia was never necessary. Postoperative pain was higher in group B (p = .01). Nine patients of group B needed analgesics, as opposed to no patient of group A (p = .002). Conclusions: The 22 Fr unipolar resectoscope appears advantageous compared to the 26 Fr resectoscope in the resection of endometrial polyps <3 cm, in terms of cervical dilatation and operative time, pain and need of postoperative analgesics. Paracervical block is useful and safe in compliant patients at high risk for general anesthesia.

Anesthesia for ambulatory surgery

Ambulatory anesthesia allows quick recovery from anesthesia, leading to an early discharge and rapid resumption of daily activities, which can be of great benefit to patients, healthcare providers, third-party payers, and hospitals. Recently, with the development of minimally invasive surgical techniques and short-acting anesthetics, the use of ambulatory surgery has grown rapidly. Additionally, as the indications for ambulatory surgery have widened, the surgical methods have become more complex and the number of comorbidities has increased. For successful and safe ambulatory anesthesia, the anesthesiologist must consider various factors relating to the patient. Among them, appropriate selection of patients and surgical and anesthetic methods, as well as postoperative management, should be considered simultaneously. Patient selection is a particularly important factor. Appropriate surgical and anesthetic techniques should be used to minimize postoperative complications, especially postoperative pain, nausea, and vomiting. Patients and their caregivers should be fully informed of specific care guidelines and appropriate responses to emergency situations on discharge from the hospital. During this process, close communication between patients and medical staff, as well as postoperative follow-up appointments, should be ensured. In summary, safe and convenient methods to ensure the patient's return to function and recovery are necessary.

Monitored anesthesia care in and outside the operating room

Monitored anesthesia care (MAC) is an anesthesia technique combining local anesthesia with parenteral drugs for sedation and analgesia. The use of MAC is increasing for a variety of diagnostic and therapeutic procedures in and outside of the operating room due to the rapid postoperative recovery with the use of relatively small amounts of sedatives and analgesics compared to general anesthesia. The purposes of MAC are providing patients with safe sedation, comfort, pain control and satisfaction. Preoperative evaluation for patients with MAC is similar to those of general or regional anesthesia in that patients should be comprehensively assessed. Additionally, patient cooperation with comprehension of the procedure is an essential component during MAC. In addition to local anesthesia by operators or anesthesiologists, systemic sedatives and analgesics are administered to provide patients with comfort during procedures performed with MAC. The discretion and judgment of an experienced anesthesiologist are required for the safety and efficacy profiles because the airway of the patients is not secured. The infusion of sedatives and analgesics should be individualized during MAC. Many procedures in and outside of the operating room, including eye surgery, otolaryngologic surgery, cardiovascular procedures, pain procedures, and endoscopy are performed with MAC to increase patient and operator satisfaction.

Monitored anesthesia care for great saphenous vein stripping surgery with target controlled infusion of propofol and remifentanil: a prospective study

Background

The aim of this study was to determine the appropriate target concentrations at the effect site of propofol and remifentanil when deep sedation was achieved by monitored anesthesia care (MAC) anesthesia and related respiratory depression during vein stripping surgery for varicose veins.

Methods

In total, 51 adult patients who were scheduled for varicose vein stripping surgery were sedated with propofol and remifentanil during the surgery, after administration of midazolam. Target concentrations at the effect site of the two drugs were changed based on the patient's status. Respiratory support was applied in the order of oxygen supply, chin lift, and assisted mask ventilation. Target concentrations at the effect site of propofol and remifentanil, the need for respiratory support, and a six-point rating scale satisfaction score were the outcome measurements.

Results

Only one patient did not require oxygen, eight patients needed oxygen alone, 22 patients required use of the chin lift technique, and 20 patients were assisted with mask ventilation. There was no significant difference in the target concentration of propofol or remifentanil between the patients who required mask ventilation and those who did not. Fifty of the 51 patients reported a satisfaction score of 6.

Conclusions

Although MAC using low target concentrations of propofol and remifentanil during vein stripping surgery was satisfactory to patients, close observation regarding the need for respiratory assistance was necessary.

Anesthesia for the elderly outpatient

PURPOSE OF REVIEW

As the number of ambulatory surgery procedures continues to grow in an aging global society, the implementation of evidence-based perioperative care programs for the elderly patients will assume increased importance.

RECENT FINDINGS

Increasing evidence supports the expanded use of ambulatory surgery for managing elderly patients undergoing elective surgery procedures.

SUMMARY

This review article describes the demographics of ambulatory surgery in the elderly population. This review article describes the effects of aging on the responses of geriatric patients to anesthetic and analgesic drugs used during ambulatory surgery. Important considerations in the preoperative evaluation of elderly outpatients with co-existing diseases, as well as the advantages and disadvantages of different anesthetic techniques on a procedural-specific basis, and recommendations regarding the management of common postoperative side-effects (including delirium and cognitive dysfunction, fatigue, dizziness, pain, and gastrointestinal dysfunction) after ambulatory surgery. Finally, we discuss the future challenges related to the continued expansion of ambulatory surgery practice in this growing segment of our surgical population. The role of anesthesiologists as perioperative physicians is of critical importance for optimizing surgical outcomes for elderly patients undergoing ambulatory surgery. Providing high-quality, evidence-based anesthetic and analgesic care for elderly patients undergoing elective operations on an ambulatory basis will assume greater importance in the future.

Anesthetic management of patients undergoing transcatheter aortic valve implantation

OBJECTIVE

To compare 2 anesthetic techniques, general anesthesia or monitored anesthesia care, performed by the same cardiac anesthesiologists for transcatheter aortic valve implantation in the authors' institution.

DESIGN

A retrospective study.

SETTING

A single specialized cardiac surgery center.

PARTICIPANTS

Ninety-eight patients with severe aortic valve stenosis and a high logistic EuroSCORE considered not eligible to undergo conventional aortic valve replacement.

INTERVENTION

General anesthesia or monitored anesthesia care.

MEASUREMENTS AND MAIN RESULTS

General anesthesia was used in 57 and monitored anesthesia care in 41 patients. The authors compared the following parameters: Duration of procedure, transfusion requirements, cardiac indices, superior vena cava saturation (ScVO2) before and after the aortic valve implantation, hospital length of stay and 30-day mortality. The only significant differences between the groups concerned were the duration of anesthesia (p<0.001) and ScVO2 values. Anesthesia duration was prolonged significantly when general anesthesia was administered, and ScVO2 was significantly higher both before and after the valve implantation in the general anesthesia group. Thirty-day mortality was 5.3% in the general anesthesia group and 4.9% in the monitored anesthesia group.

CONCLUSIONS

It would appear that both anesthetic techniques may be used for patients with a high logistic EuroSCORE undergoing transcatheter aortic valve implantation.

Fire in the surgical center

BACKGROUND AND OBJECTIVES

There are several factors in operating rooms that increase the risk of fire. Besides being an oxygen-enriched environment, it contains combustible materials and equipment with available ignition sources. Although fires in operating rooms are a relatively rare event, the consequences are potentially serious and mostly avoidable. We present a case report of a fire occurring in the surgical drape during a blepharoplasty in which oxygen was supplemented by nasal catheter.

CASE REPORT

Female patient, 52-years old, without comorbidities, admitted to hospital for a bilateral blepharoplasty. After monitoring and venoclysis, the patient underwent intravenous sedation and additional oxygen given via spectacle-type catheter at a flow rate of4 L.min(-1), followed by local anesthesia in the eyelids. During surgery, the use of electric scalpel provoked combustion in the surgical drapes and burns on the patient's face.

CONCLUSIONS

Anesthesiologists play an important role preventing fire in operating rooms, as they can recognize possible ignition sources and rationally administer the oxygen, especially in open systems. The first step toward prevention is to be constantly aware of potential fire.

Perioperative care for the older outpatient undergoing ambulatory surgery

As the number of ambulatory surgery procedures continues to grow in an aging global society, the implementation of evidence-based perioperative care programs for the elderly will assume increased importance. Given the recent advances in anesthesia, surgery, and monitoring technology, the ambulatory setting offers potential advantages for elderly patients undergoing elective surgery. In this review article we summarize the physiologic and pharmacologic effects of aging and their influence on anesthetic drugs, the important considerations in the preoperative evaluation of elderly outpatients with coexisting diseases, the advantages and disadvantages of different anesthetic techniques on a procedural-specific basis, and offer recommendations regarding the management of common postoperative side effects (including delirium and cognitive dysfunction, fatigue, dizziness, pain, and gastrointestinal dysfunction) after ambulatory surgery. We conclude with a discussion of future challenges related to the growth of ambulatory surgery practice in this segment of our surgical population. When information specifically for the elderly population was not available in the peer-reviewed literature, we drew from relevant information in other ambulatory surgery populations.

Comparison between local anaesthesia with remifentanil and total intravenous anaesthesia for operative hysteroscopic procedures in day surgery

BACKGROUND

This study aimed at comparing total i.v. anaesthesia (TIVA) with monitored anaesthesia care (MAC) during day-surgery operative hysteroscopy regarding: operation time, time to mobilization and discharge, and patient satisfaction.

METHODS

Ninety-one healthy women were randomized to MAC with paracervical local anaesthesia and remifentanil or to TIVA with propofol and remifentanil. Time from arrival to leaving the operating theatre, time from arrival in the recovery room to mobilization and discharge readiness, and patient satisfaction with MAC and TIVA were observed.

RESULTS

Time from arrival to leaving the operating theatre showed no significant difference between groups (P=0.6). The time to mobilization {MAC: 53 min [inter-quartile range (IQR) 40-83], TIVA: 69 min (IQR 52-96) (P=0.017)} and the total time from arrival to discharge readiness [MAC: 118 min (IQR 95-139), TIVA: 138 (IQR 120-158) (P=0.0009)] were significantly reduced for patients in the MAC group. More patients in the MAC group 45 (91.8%) than in the TIVA group 24 (64.9%) responded positively to the question: would you like to receive the same kind of anaesthesia for a similar procedure in the future? (P=0.003).

CONCLUSIONS

Paracervical local anaesthesia combined with remifentanil is suitable for operative hysteroscopy in day surgery.

Remifentanil for the insertion and removal of long-term central venous access during monitored anesthesia care

STUDY OBJECTIVE

To determine the analgesic efficacy of three different rates of remifentanil infusion in patients undergoing insertion or removal of long-term central venous access devices during monitored anesthesia care and local anesthetic field infiltration.

DESIGN

Double-blinded, randomized, controlled study.

SETTING

Operating theatre of an University hospital.

PATIENTS

44 unpremedicated, ASA physical status 1 and 2 patients, aged 18-65 years, undergoing insertion or removal of a Port-a-Cath or Hickman catheter.

INTERVENTIONS

Patients sedated with a propofol target-controlled infusion were randomly allocated to three groups: Group R25 (n = 14), Group R50 (n = 15), and Group R75 (n = 15), to receive remifentanil 0.025, 0.05, and 0.075 μg/kg/min, respectively. Rescue remifentanil 0.5 μg/kg was administered for pain scores > 3. The remifentanil infusion rate was maintained constant unless respiratory and/or cardiovascular unwanted events occurred, whereupon the rate was adjusted in 0.01 μg/kg/min decrements as necessary.

MEASUREMENTS

Pain scores (primary outcome), sedation, and movement scores (secondary outcomes) were assessed during local anesthetic infiltration of the anterior chest wall and 5 other procedural steps.

MAIN RESULTS

All infusion rates had equal analgesic efficacy, as shown by comparable pain scores, number of rescue boluses, and number of patients requiring rescue analgesia. Excessive sedation was associated with the highest remifentanil rate such that Group R75 patients were significantly more sedated than Groups R25 or R50 at selective procedural steps (P < 0.05). More Group R75 patients (6/15) required remifentanil rate reduction than did patients from Group R50 (1/15) or Group R25 (0/14), P < 0.01, most commonly because of respiratory depression.

CONCLUSIONS

For the insertion or removal of long-term central venous access devices, all three remifentanil infusion rates proved to be equally analgesic-efficient. However, the excessive sedation and tendency to respiratory and cardiovascular events associated with the highest remifentanil infusion rate renders such a rate less desirable for this purpose.

Efficacy and cost analysis of transrectal ultrasound-guided prostate biopsy under monitored anesthesia

Sedation may result in reduction in pain during transrectal ultrasound (TRUS)-guided prostate biopsies. We aimed to evaluate the efficacy and safety of a combination of propofol and remifentanil infusion during TRUS-guided prostate biopsy and the related increases in health care costs. From January to September 2010, 100 men undergoing a transrectal prostate biopsy were randomized into two groups. In Group 1, 50 patients received a combined infusion of propofol and remifentanil; in Group 2, 50 patients received lidocaine jelly. After TRUS-guided biopsies were performed, pain and patient satisfaction were evaluated by a 10-point visual analog scale (VAS), and a cost-related patient satisfaction questionnaire was completed by all patients. Patients were also asked whether they would be willing to undergo repeat biopsy by the same method. Patients in Group 1 showed a significantly lower VAS score than those in Group 2 (mean VAS score: 0.9±1.1 versus 6.3±2.5; P<0.001). In addition, the patient satisfaction scale was significantly higher in Group 1 (P=0.002). Although the overall cost was significantly higher in Group 1 (P=0.006), patient satisfaction scales considering cost were also higher in this group (P=0.009). A combination of propofol and remifentanil is a safe and effective way to decrease patient pain and increase patient satisfaction during TRUS-guided prostate biopsy. Although the costs were higher in the group that received sedation, as expected, the patients exhibited heightened satisfaction and willingness to repeat biopsies by the same method.

Ultrasound-guided transversus abdominis plane block for spinal infusion and neurostimulation implantation in two patients with chronic pain

OBJECTIVE

This case report describes an ultrasound approach to the transversus abdominis plane (TAP) local anesthetic block. This block induces sensory blockade in the lower half of the abdomen where the pulse generator or the infusion pump is to be housed in a subcutaneous pocket, and therefore provides an alternate to general anesthesia or administration of high-dose local anesthetics.

CASE REPORT

We report two cases of neuromodulation procedures-implantation of an internal morphine pump for severe somatic pain refractory to other therapies and placement of a double-stimulator generator for dorsal column stimulation in a patient diagnosed with postoperative failed-back syndrome. We successfully used ultrasound-guided TAP block to achieve ipsilateral sensory block of dermatomes T9-L1 in the context of a monitored anesthesia care multimodal approach.

CONCLUSION

TAP block can be a potentially useful substitute to general anesthesia or local anesthesia for the pocket formation in neuromodulation techniques, and it provides adequate anesthesia of the abdominal wall. This block is potentially an important addition to the monitored anesthesia care protocol.

Median effective infusion dose (ED50) of alfentanil for monitored anesthesia care of percutaneous vertebroplasty of osteoporotic fractures

Percutaneous vertebroplasty (PVP) consists of injecting small quantities of orthopedic cement to consolidate pathologic vertebral bodies. The procedure is brief but painful during vertebral puncture and cement injection requiring either general anesthesia or monitored anesthesia care with opioids. The optimal dose of alfentanil in this setting is unknown. Therefore, we sought to determine its median effective dose (ED50, or analgesic efficacy in 50% of patients) during PVP in none intubated, spontaneously breathing patients. After approval and informed consent of the Institutional Review Board, 50 patients (American Society of Anesthesiologists II-III, age 50 to 80, weight: 53 to 82 kg) with osteoporotic vertebral fractures were enrolled. The patients were premedicated with oral hydroxyzine 100 mg and had skin infiltration with 50 mg lidocaine before vertebral puncture. The prone position was adopted and oxygen was provided via a facemask. Noninvasive cardiorespiratory variables were monitored. Pain was evaluated by a numerical pain scale (NPS) where 0 represents no pain and 10 the worst tolerable pain. Alfentanil infusion was started 30 minutes before vertebral puncture. The initial dose was 2.0 mg/h. Thereafter, a 0.05 mg/h decrease or increase was applied to the next patient if analgesia was effective (NPS: 3 or less) or not (NPS>3) according to the Dixon method. The bootstrap resampling technique was used to calculate the ED50 and its 95% confidence limits. The latter was 1.05 mg/h (95% confidence interval, 1.0-1.2). Transient apnea (n=2) and nausea/vomiting (n=3) were observed. Given the median body weight of the patients (65 kg), we conclude that 0.27 microg kg/min of alfentanil provides effective analgesia for PVP under monitored anesthesia care.

SUMMARY STATEMENT

PVP consists of injecting small quantities of orthopedic cement to consolidate pathologic vertebral bodies. The median effective dose (ED50) for pain relief during vertebral puncture and cement injection is 1.05 (95% confidence interval, 1.0-1.2) mg/h when infusion is started 30 minutes before the procedure. Given the median body weight of our study population (65 kg), this dose corresponds to 0.27 microg kg/min.

Randomized clinical trial of Entonox versus midazolam-fentanyl sedation for colonoscopy

BACKGROUND

Intravenous sedation for colonoscopy is associated with cardiorespiratory complications and delayed recovery. The aim of this randomized clinical trial was to compare the efficacy of Entonox (50 per cent nitrous oxide and 50 per cent oxygen) and intravenous sedation using midazolam-fentanyl for colonoscopy.

METHODS

Some 131 patients undergoing elective colonoscopy were included. Patients completed a Hospital Anxiety and Depression questionnaire, letter cancellation tests and pain scores on a 100-mm visual analogue scale before, immediately after the procedure and at discharge. They also completed a satisfaction survey at discharge and 24 h after the procedure.

RESULTS

Sixty-five patients were randomized to receive Entonox and 66 to midazolam-fentanyl. Completion rates were similar (94 versus 92 per cent respectively; P = 0.513). Patients receiving Entonox had a shorter time to discharge. They reported significantly less pain (mean score 16.7 versus 40.1; P < 0.001), and showed better recovery of psychomotor function immediately after the procedure and at discharge. Patient satisfaction was higher among patients who received Entonox (median score 96 versus 89; P = 0.001).

CONCLUSION

Entonox provides better pain relief and faster recovery than midazolam-fentanyl and so is more effective for colonoscopy.

Thyroid surgery under monitored anesthesia care (MAC)

BACKGROUND

Thyroid surgery is usually performed under general anesthesia, but thyroid surgery under monitored anesthesia care (MAC) has become re-introduced. We report our experiences of 40 cases of thyroid surgery under MAC.

METHODS

Forty patients were enrolled in this study. Bilateral superficial cervical plexus block (BSCPB) was performed by using 1% mepivacaine with 1 : 200,000 epinephrine. After BSCPB, patients were sedated with propofol and fentanyl. Postoperative pain, sore throat, hoarseness, and postoperative nausea and vomiting (PONV) were assessed.

RESULTS

Mean postoperative pain VAS were 1.3, 1.2, 1.0, 0.8 and postoperative sore throat VAS 1.4, 1.4, 1.1, 0.9 at PACU (post-anesthesia care unit) and postoperative 3, 6, 12 h, respectively. The incidence of hoarseness was 25, 5, 2.5%, and 0% and PONV were 0, 5, 10%, and 7.5% at PACU and postoperative 3, 6, 12 h, respectively.

CONCLUSIONS

Thyroid surgery under MAC may be a suitable alternative to general anesthesia.

Fire safety in the operating room

PURPOSE OF REVIEW

Elimination of flammable anesthetic gases has had little effect on operating-room fires except to change their etiology. Electrocautery and lasers, in an oxygen-enriched environment, can ignite even the most fire-resistant materials, including the patient, and the fire triad possibilities in the operating room are nearly limitless. This review will: identify operating room contents capable of acting as ignition/oxidizer/fuel sources, highlight operating room items that are uniquely potent fire triad contributors, and operating room identify settings where fire risk is enhanced by proximity of triad components in time or space.

RECENT FINDINGS

Anesthesiologists are cognizant of the risk of airway surgery fires due to laser ignition of the endotracheal tube and/or its contents. Recently, however, head/neck surgery under monitored anesthesia care has emerged as a high-risk setting for operating room fires; burn injuries represent 20% of monitored anesthesia care-related malpractice claims, 95% of which involved head/neck surgery.

SUMMARY

Operating room fires are infrequent but catastrophic. Operating room fire prevention depends on: (a)understanding how fire triad elements interact to create a fire, (b) recognizing how standard operating-room equipment, materials, and supplemental oxygen can become one of those elements, and (c) vigilance for circumstances that bring fire triad elements into close proximity.

Anesthesia for outpatient cosmetic surgery

PURPOSE OF REVIEW

American Society of Aesthetic Plastic Surgery statistics show outpatient cosmetic procedures increased from 3 to 11 million (1997-2007), an increase of 457%, and $13 billion was spent. Exponential growth, complexity of cases and patients, and media attention to high-profile untoward events are accompanied with concerns for patient safety and development of safer anesthesia practices.

RECENT FINDINGS

Improved safety and efficacy in aesthetic facial surgery include oral sedation and local anesthesia, addition of dexmedetomidine to intravenous anesthesia, and defining the 'safest' dose of lidocaine with epinephrine. A nasopharyngeal tube can be used to deliver a concentration of oxygen commensurate with recent American Society of Anesthesiologists Task Force Practice Advisory for the prevention and management of operating room fires. Analgesia for breast surgery including instillation of bupivicaine, paravertebral block, and combination dexamethasone with nonsteroidal anti-inflammatory drugs can decrease narcotic requirement and recovery time. Risks of combined gynecologic and plastic surgical procedures are not greater than those seen with either procedure alone. A coordinated team approach for patient management is essential. Pulmonary embolism remains the greatest cause of mortality.

SUMMARY

The methods presented improve patient safety. The number of cosmetic procedures will continue to grow exponentially and evolve additional patient safety concerns. This larger population is the foundation for prospective trials to develop evidence-based anesthesia for cosmetic surgery.

Fast-track anesthetic techniques for ambulatory surgery

PURPOSE OF REVIEW

Improving perioperative efficiency and throughput has become increasingly important in facilitating the fast-track recovery process following ambulatory surgery. This review focuses on the important role played by the anesthesiologist as a perioperative physician in fast-track ambulatory surgery.

RECENT FINDINGS

A literature review of more than 200 peer-reviewed publications was used to develop evidence-based recommendations for optimizing recovery following ambulatory anesthesia. The choice of anesthetic technique should be tailored to the needs of the patient as well as the type of surgical procedure being performed in the ambulatory setting. The anesthetic decisions made by the anesthesiologist, as a key perioperative physician, are of critical importance in developing a successful fast-track ambulatory surgery program.

SUMMARY

The pivotal role played by the anesthesiologist as the key perioperative physician in facilitating the recovery process has assumed increased importance in the current outpatient fast-track recovery environment. The choice of premedication, anesthetic, analgesic and antiemetic drugs, as well as cardiovascular, hormonal and fluid therapies, can all influence the ability to fast-track outpatients after ambulatory surgery.

Malpractice issues in modern anaesthesiology

Medical malpractice has been raised as an important problem in daily practice, while the media and public remain unforgiving to those perceived to have harmed the patients' life. This article highlights important legal issues related to medical malpractice and summarizes the sources and the nature of potential errors in anaesthesiology practice.

Sedation Analgesia during Office-Based Plastic Surgery Procedures: Comparison of Two Opioid Regimens

BACKGROUND

The combination of sedative and analgesic drugs is increasingly being used during minimally invasive surgery. The authors compared the clinical efficacy of two different fentanyl regimens, in combination with midazolam, for sedation analgesia in patients undergoing office-based plastic surgery procedures under local anesthesia.

METHODS

One-hundred patients were randomized into two groups of 50 subjects each. Group F1 received a fentanyl bolus of 0.7 microg/kg before infiltration with local anaesthetics; group F2 received the same bolus plus 0.6 microg/kg fentanyl every 45 minutes. All patients received a midazolam bolus of 0.05 mg/kg plus continuous infusion 0.08 mg/kg per hour.

RESULTS

High-quality analgesia was obtained in every group, without significant differences between the two fentanyl regimens. Group F2 was associated with lower intraoperative mean blood pressure and SpO2 values compared with group F1. No differences were detected between the two groups in perioperative side effects or postoperative pain.

CONCLUSION

Higher doses of opioid did not improve the quality of perioperative patient comfort but acted synergistically with the sedative drugs, amplifying the hemodynamic and respiratory side effects.

The Role of the Anesthesiologist in Fast-Track Surgery: From Multimodal Analgesia to Perioperative Medical Care

BACKGROUND

Improving perioperative efficiency and throughput has become increasingly important in the modern practice of anesthesiology. Fast-track surgery represents a multidisciplinary approach to improving perioperative efficiency by facilitating recovery after both minor (i.e., outpatient) and major (inpatient) surgery procedures. In this article we focus on the expanding role of the anesthesiologist in fast-track surgery.

METHODS

A multidisciplinary group of clinical investigators met at McGill University in the Fall of 2005 to discuss current anesthetic and surgical practices directed at improving the postoperative recovery process. A subgroup of the attendees at this conference was assigned the task of reviewing the peer-reviewed literature on this topic as it related to the role of the anesthesiologist as a perioperative physician.

RESULTS

Anesthesiologists as perioperative physicians play a key role in fast-track surgery through their choice of preoperative medication, anesthetics and techniques, use of prophylactic drugs to minimize side effects (e.g., pain, nausea and vomiting, dizziness), as well as the administration of adjunctive drugs to maintain major organ system function during and after surgery.

CONCLUSION

The decisions of the anesthesiologist as a key perioperative physician are of critical importance to the surgical care team in developing a successful fast-track surgery program.

Prospective randomized controlled trial comparing three different ways of anesthesia in transrectal ultrasound-guided prostate biopsy

PURPOSE

To make an objective controlled comparison of pain tolerance in transrectal ultrasound-guided prostatic biopsy using intrarectal topic anesthesia, injectable periprostatic anesthesia, or low-dose intravenous sedation.

MATERIALS AND METHODS

One hundred and sixty patients were randomized into 4 groups: group I, intrarectal application of 2% lidocaine gel; group II, periprostatic anesthesia; group III, intravenous injection of midazolam and meperidine; and group IV, control, patients to whom no sedation or analgesic was given. Pain was evaluated using an analogue pain scale graded from 0 to 5. Acceptance of a repetition biopsy, the side effects of the drugs and complications were also evaluated.

RESULTS

18/20 (90%) and 6/20 (30%) patients reported strong or unbearable pain in the group submitted to conventional biopsy and topical anesthesia (p = 0.23, chi-square = 1.41); whereas those submitted to periprostatic blockade and sedation, severe pain occurred in only 2/60 (3%) patients (p < 0.001, chi-square = 40.19) and 3/60 (5%) patients (p < 0.001, chi-square = 33.34). Acceptance of repetition of the biopsy was present in only 45% of the patients submitted to conventional biopsy, 60% of those that were given topical anesthesia (p = 0.52, chi-square = 0.4), compared to 100% of those submitted to periprostatic anesthesia (p < 0.01, chi-square = 15.17), and 95% of those who were sedated (p < 0.001, chi-square = 25.97%).

CONCLUSIONS

Transrectal ultrasound-guided prostatic biopsy is an uncomfortable experience; however application of periprostatic blockade and intravenous analgesia are associated to higher tolerance of the exam and patient comfort. Low dose sedation by association of intravenous meperidine and midazolam is an emerging and safe outpatient option.

Comparison of propofol with propofol-ketamine combination in pediatric patients undergoing auditory brainstem response testing

OBJECTIVE

The aim of our study was to compare propofol with propofol-ketamine combination for sedation and also to compare related complications in children undergoing auditory brainstem response (ABR) testing.

METHODS

Sixty ASA I-II patients aged between 1 and 13 years of age were sedated for ABR testing. Propofol 1.5mg/kg was used in group P (n=30), and ketamine 0.5 mg/kg+propofol 1.5 mg/kg, i.v., in group PK (n=30). Sedation levels of patients were maintained between scores 3 and 4 according to Ramsey sedation scores; when necessary, half of the starting drug dosage was administered for the maintenance of sedation. Side effects which occurred during or within the first 24h of the procedure were assessed.

RESULTS

Additional dosage was needed for 21 cases in group P and eight cases in group PK (p=0.002). While oxygen desaturation and apnea were not observed in any of the patients in group PK, there were four patients (11.4%) with oxygen desaturation, and six (17.1%) with apnea in group P (p<0.05).

CONCLUSIONS

In pediatric cases where ABR testing was applied, addition of low dose ketamine to propofol avoided the risk of respiratory depression due to propofol and lowered the need for additional dose of propofol. Therefore, the co-administration of propofol and ketamine appears to be a safe and useful technique for ABR testing.

Sedation with target-controlled propofol infusion during shoulder surgery under interscalene brachial plexus block in the sitting position

BACKGROUND AND OBJECTIVE

The aim of this study was to assess target-controlled propofol infusion as a technique of sedation for shoulder surgery under interscalene brachial plexus block in the sitting position and to evaluate the effect of sedation on hypotensive/bradycardic events during this procedure.

METHODS

One hundred and forty patients undergoing elective shoulder surgery in the sitting position under interscalene brachial plexus block (with 30 mL of ropivacaine 0.75%) were prospectively enrolled. All patients were premedicated with hydroxyzine 1 mg kg(-1), none received beta-blockers. No patients were given atropine except for the patients who experienced a vasovagal event either during the block procedure or intravenous catheter placement. The target-controlled propofol infusion was started immediately after positioning the patient on the operating table. The initial target concentration was 1 microg mL(-1). The infusion rate was adjusted every 15 min by increasing or decreasing the target concentration by 0.2 microg mL(-1) steps to maintain the patient rousable to verbal commands (score of 3 on Wilson sedation scale). The following parameters were assessed: minimal, maximal, optimal target concentration, respiratory and haemodynamic parameters, total propofol dose, additional alfentanil needs, occurrence of hypotensive/bradycardic events, complications. Results are mean +/- SD. Statistical analysis used t-test and chi2-tests.

RESULTS

The optimal propofol target concentration was 0.8 mug mL(-1). No respiratory complications or conversion to general anaesthesia was reported. Two patients experienced transient and inconsequential intraoperative agitation. The incidence of hypotensive/bradycardic events during the procedure was 5.7% (eight patients).

CONCLUSION

Target-controlled propofol infusion (0.8-0.9 microg mL(-1)) following hydroxyzine premedication is a safe and effective technique for sedation when combined with interscalene brachial plexus block during shoulder surgery in the sitting position.

Local anesthesia with sedation for vaginal reconstructive surgery

To evaluate local anesthesia with sedation for vaginal reconstructive surgery. All cases of vaginal surgery performed by the primary author for correction of pelvic organ prolapse with and without urinary incontinence between February 2000 and October 2004 were identified. From the medical record, data on age, duration of surgery, amount of local anesthetic used, estimated blood loss, hospital stay, urinary retention, and need for conversion to general anesthesia were recorded. Among 127 potential candidates, 98 (77.2%) opted for local with sedation. These cases included 18 anterior colporrhaphies, 47 posterior colporrhaphies with perineoplasties, 9 enterocele repairs, 32 total colpocleises, and 9 LeFort procedures. Tension-free vaginal tape (TVT) were concomitantly placed in 37 of the cases; 121 TVT-only cases done under local were not included. No cases were converted to general anesthesia. Surgical time ranged from 20 to 195 min (mean 99 min). Most patients were discharged within 24 h of surgery. Traditionally, local anesthesia with sedation has been reserved for superficial vaginal procedures. However, it can be successfully employed for more invasive vaginal reconstructive surgeries. Duration of surgery and patient acceptance have not been limiting factors. The advantages of local anesthesia include minimal interference with homeostasis and rapid recovery with patients often bypassing the recovery unit.

Moderate Intravenous Sedation for Office-Based Full Face Laser Resurfacing Using a Continuous Infusion Propofol Pump

PURPOSE

The purpose of this study was to compare the anesthetic requirements and hemodynamic and oxygenation variables involved between the bolus midazolam/fentanyl intravenous sedation-analgesia technique, and the same technique combined with continuous-infusion propofol.

PATIENTS AND METHODS

This was a retrospective chart analysis of 41 consecutive patients undergoing full-face carbon dioxide laser resurfacing with either bolus midazolam/fentanyl (n = 15) or midazolam/fentanyl with continuous propofol infusion anesthesia (n = 26) techniques. Data recorded were noninvasive baseline and intraoperative hemodynamic measurements at 5-minute intervals for systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), pulse pressure (PP), pulse (P), and rate-pressure product (RPP), respiratory rate (RR), and oxygen saturation (SpO2). Data collected were reported as mean values with standard deviation. Statistical analyses were performed with the Student's t test and found statistically significant for P < .05.

RESULTS

Statistically significant decreases in averages were seen in SBP (P < .001), DBP (P = .02), MAP (P = .004), P (P < .00l), RPP (P < .00l), and RR (P < .001), but not PP (P = .4) and SpO2 (P = .08) in the midazolam/fentanyl/continuous propofol infusion group compared with the midazolam/fentanyl only group. Changes from baseline were statistically significant only for MAP (P = .04), but statistically insignificant for all other measurements, SBP (P = .7), DBP (P = .4), P (P = .95), PP (P = .97), RPP (P = .6), RR (P = .6), and SpO2 (P = .4). Statistically significant smaller amounts of midazolam (P = .01) and fentanyl (P < .001) were used in the midazolam/fentanyl/continuous propofol infusion pump group. Length of procedure was statistically insignificant between groups (P = .4). Conclusion The addition of a continuous propofol pump maintained hemodynamic and oxygenation values close to baseline, while decreasing the amount of respiratory depressing opiates administered and without affecting the length of the procedure.

Local anesthesia for stapled prolapsectomy in day surgery: results of a prospective trial

PURPOSE

This article reports the results of a prospective trial of the feasibility of Longo's procedure under local anesthesia in day surgery.

METHODS

From April 2002 to May 2003, 66 patients (42 males and 24 females) were enrolled in the study; the mean age was 47.5 (range, 23-65) years. Thirty-six patients (55 percent) had prolapsed third-degree hemorrhoids, while 30 (45 percent) had fourth-degree hemorrhoids. All patients were operated on under local infiltration of the anorectal region by injecting ropivacaine 7.5 mg/dl using a Quadrijet. During the surgical procedure, blood pressure and heart rate were always monitored and the level of pain was checked using a visual analog scale. Hospital discharge was programmed for 6:00 p.m. Any immediate complications, such as bleeding, urinary retention, or pain, were also recorded.

RESULTS

It was possible to perform the procedure under local anesthesia in all patients, and the anesthesiologist did not need to intervene at any time. No vagal reaction was observed; the transient reduction of blood pressure and heart rate, which occurred in four patients (6 percent),was controlled with an analgesic drug. In 96 percent of the cases the mean intraoperative visual analog score was not higher than four. Fifty-six patients were discharged at 6:00 p.m., while only 10 percent required an overnight stay.

CONCLUSIONS

The stapled prolapsectomy procedure is feasible and can be performed safely under local anesthesia and as day surgery. This procedure provides good pain control and results in a minimal number of complications.

A comparison of fentanyl-propofol with a ketamine-propofol combination for sedation during endometrial biopsy

STUDY OBJECTIVE

The purpose of this study was to compare the clinical activities of ketamine and fentanyl when used in combination with propofol for outpatients undergoing endometrial biopsy. The investigated parameters were respiration, sedation, recovery rate, side effects, time to discharge, and patient satisfaction.

DESIGN

Prospective, randomized, double-blind study.

SETTING

University hospital.

PATIENTS

Forty American Society of Anesthesiologists physical status I and II patients (age range 38-61 years) scheduled for elective endometrial biopsy.

INTERVENTIONS

Patients received intravenous bolus doses of either fentanyl 1 microg/kg and propofol 1 mg/kg in (group 1 n = 20) or ketamine 0.5 mg/kg and propofol 1 mg/kg in (group 2 n = 20).

MEASUREMENTS

Heart rate, systolic and diastolic blood pressure, respiratory rate, and peripheral O(2) saturation were monitored in all patients. Depth of sedation was assessed by the Ramsay sedation score. The Aldrete score was used for postoperative recovery evaluation. The time to Aldrete score >/=8, side effects, and time to discharge were recorded.

MAIN RESULTS

Respiratory depression was observed in 5 patients from group 1 and 1 patient from group 2, but the difference was not significant (P > .05). Nausea, vertigo, and visual disturbances were more frequent in group 2 (P < .05). The time to Aldrete score >/=8 was similar in the 2 groups (6.2 +/- 3.5 minutes in group 1 and 7.0 +/- 3.1 minutes in group 2); the time to discharge was significantly longer in group 2 (71.2 +/- 9.7 minutes in group 1 and 115.2 +/- 25.6 minutes in group 2). Frequency of patient satisfaction was 95% in group 1 and 60% in group 2.

CONCLUSIONS

Hemodynamic change and degrees of sedation showed that fentanyl-propofol and ketamine-fentanyl combinations can be used safely in patients undergoing endometrial biopsy. However, with regard to side effects and patient satisfaction, the fentanyl-propofol was superior.

Sedation with GPI 15715, a Water-Soluble Prodrug of Propofol, Using Target-Controlled Infusion in Volunteers: Retracted

GPI 15715 is the first water-soluble propofol prodrug that has been studied in humans. Present propofol lipid formulations have well known undesirable properties, for example, pain on injection and increased triglyceride concentrations. We investigated whether GPI 15715 is suitable to achieve and maintain moderate sedation for 2 h. Six male and six female volunteers received a target-controlled infusion of GPI 15715, with an initial propofol target concentration of 1.8 microg/mL and the possibility to adjust the propofol target once after 1 h. Propofol concentrations, the bispectral index, and modified Observer's Assessment of Alertness/Sedation Scale (MOAA/S) scores were monitored. The median MOAA/S score was 4 during the first hour and was 3 during the second hour of infusion. The propofol target had to be changed to 2.4 microg/mL in seven volunteers and to 3.0 microg/mL in two volunteers. A propofol concentration of 1.9 microg/mL had the highest probability to result in an MOAA/S score of 3, which corresponds with moderate sedation. We observed no serious side effects. We conclude that GPI 15715 produces excellent sedation.

Evaluation of gustatory function after third molar removal

The aim of this study was to determine the severity of taste changes after surgical removal of all four third molars in one session. Taste function in 27 patients was measured before and at 1 month and 6 months after surgery. In every patient all four third molars were removed using local anesthesia and sedation with midazolam and fentanyl. For testing gustatory function, two tests were administered: a whole-mouth, above threshold test and a spatial (localized) taste test. For this purpose, sucrose, NaCl, citric acid and quinine hydrochloride solutions were used. Taste intensity of quinine hydrochloride of the palate was significantly reduced 1 month after surgery (P < 0.05) but recovered and reach to preoperative values 6 months after surgery. The results showed that there were no significant changes in gustatory function after third molar surgery.

Les morphiniques (sufentanil et rémifentanil) en neuro-anesthésie

Remifentanil is the latest available compound of the 4-anilidopiperidine derivatives. It is characterized by an ultrashort duration of action and a metabolism independent of both hepatic and renal functions. Its main drawback is a lack of residual analgesia and the risk of postoperative hyperalgesia. Since its introduction in clinical practice, this drug has been compared to other congeners in a few studies in the setting of neurosurgery. Cerebral hemodynamics, intracranial pressure and CO(2) reactivity are similar to the effects of fentanyl and sufentanil provided that systemic arterial pressure is maintained. Haemodynamics does not greatly vary according to the type of the opioid. Fentanyl and sufentanil require higher hypnotic dosage (halogenated agents, propofol) and remifentanil is accompanied by greater volumes of fluid infusion. A marked reduction in extubation times and superior level of consciousness are reported with remifentanil. Rescue analgesic has to be given faster but pain scores remain low. Morphine 0.08 mg/kg IV administered at bone replacement results in good postoperative analgesia without delayed recovery. In summary, remifentanil is appropriate when rapid recovery and neurological evaluation are desired. Conversely, sufentanil is more suitable and easier to administer when postoperative mechanical ventilation and postponed awakening are scheduled.