Search

Introduction: Pain after cervicofacial cancer surgery with free flap reconstruction is both underestimated and undertreated. There is a rational for regional anesthesia at the flap harvest site, but few studies describe it. We assessed the influence of common peroneal nerve infiltration on pain and opioid consumption in patients having oropharyngeal cancer surgery with fibular free flap mandibular reconstruction. Methods: After institutional review board (IRB) approval and written informed consent, fifty-six patients were randomly allocated to perineural catheter with ropivacaine infiltration (ROPI) or systemic analgesia (CONTROL). In the ROPI group, an epidural catheter was placed by the surgeon before closure, and ropivacaine 0.2% 15 mL, followed by 4 mL/h during 48 h, was administered. The primary outcomes were pain scores and morphine consumption during the 48 h postoperative period. We also measured ropivacaine concentration at the end of infusion. Finally, we retrospectively assessed long-term pain up to 10 years using electronic medical charts. Results: Perineural infiltration of ropivacaine significantly reduced pain scores at the harvest site only at day 1, and did not influence overall postoperative opioid consumption. Ropivacaine assay showed a potentially toxic concentration in 50% of patients. Chronic pain was detected at the harvest site in only one patient (ROPI group), and was located in the cervical area in the case of disease progression. Discussion: Although the catheter was visually positioned by the surgeon, continuous ropivacaine infiltration of the common peroneal nerve did not significantly reduce postoperative pain, but induced a blood concentration close to the toxic threshold at day 2. Further studies considering other infiltration locations or other dosing schemes should be tested in this context, both to improve efficacy and reduce potential toxicity.

Background: Despite its anticipation, postoperative pain may be still poorly managed in some cases, such as in patients undergoing major cervicofacial cancer surgery. Indeed, the postoperative pain associated with these surgeries is complex and multifactorial. Objective: To assess the profile of postoperative pain scores and opioid requirements in a cohort of consecutive patients undergoing major cancer cervicofacial surgery with or without reconstruction. Methods: A cohort of 42 consecutive patients was studied. The following parameters were recorded: patients characteristics, type of surgery, preoperative medication preoperative pain scores, and postoperative pain score (5-point numerical verbal scale) upon arrival at the postanesthesia care unit (PACU) and at Day 1 to Day 7 (11-point visual numeric scale), the presence or absence of neuropathic and/or chronic pain one year later (determined by a phone interview), and morphine consumption. Results: All patients had a pain score of less than 3 in the PACU. From postoperative day 1 to day 7, pain scores were extremely variable and stayed high or even increased up to 7 in many patients. At the one-year phone interview, some patients had neuropathic and chronic pain.Discussion: Postoperative pain profiles in major cervicofacial cancer are complex, with high interindividual variability and with cases with neuropathic patterns and high pain scores that can last up to 7 days postoperatively.

Intraoperative anaesthesia management in oro-facial cancer surgical patients requiring free flap tissue transfer is evolving. In this paper we updated our intraoperative clinical protocol using our own experience in combination with the latest literature. The main areas of change include videolaryngoscopic awake intubation in case of difficult airway management, combination of regional anaesthesia with peripheral catheter to decrease intraoperative opioid consumption, and postoperative pain and finally opioid free anaesthesia techniques using dexmedetomidine.

Postoperative management of complex cervico-facial cancer tumor removal followed by free flap reconstruction is evolving since its early beginning 20 years ago. Flap surveillance is a major goal in this period, however the management of comorbidities to predict a favorable outcome cannot be neglected. Based on our experience in this field and recent literature we updated our postoperative management protocol which focus on management of different comorbidities to maintain favorable outcome for the graft and the patient.

International audience; Objectives: To provide an update to the 1999 French guidelines on “Muscle relaxants and reversal in anaesthesia”, a consensus committee of sixteen experts was convened. A formal policy of declaration and monitoring of conflicts of interest (COI) was developed at the outset of the process and enforced throughout. The entire guidelines process was conducted independently of any industrial funding (i.e. pharmaceutical, medical devices). The authors were required to follow the rules of the Grading of Recommendations, Assessment, Development and Evaluation (GRADE®) system to assess the quality of the evidence on which the recommendations were based. The potential drawbacks of making strong recommendations based on low-quality evidence were stressed. Few of the recommendations remained ungraded. Methods: The panel focused on eight questions: (1) In the absence of difficult mask ventilation criteria, is it necessary to check the possibility of ventilation via a facemask before muscle relaxant injection? Is it necessary to use muscle relaxants to facilitate facemask ventilation? (2) Is the use of muscle relaxants necessary to facilitate tracheal intubation? (3) Is the use of muscle relaxants necessary to facilitate the insertion of a supraglottic device and management of related complications? (4) Is it necessary to monitor neuromuscular blockade for airway management? (5) Is the use of muscle relaxants necessary to facilitate interventional procedures, and if so, which procedures? (6) Is intraoperative monitoring of neuromuscular blockade necessary? (7) What are the strategies for preventing and treating residual neuromuscular blockade? (8) What are the indications and precautions for use of both muscle relaxants and reversal agents in special populations (e.g. electroconvulsive therapy, obese patients, children, neuromuscular diseases, renal/hepatic failure, elderly patients)? All questions were formulated using the Population, Intervention, Comparison and Outcome (PICO) model for clinical questions and evidence profiles were generated. The results of the literature analysis and the recommendations were then assessed using the GRADE® system. Results: The summaries prepared by the SFAR Guideline panel resulted in thirty-one recommendations on muscle relaxants and reversal agents in anaesthesia. Of these recommendations, eleven have a high level of evidence (GRADE 1±) while twenty have a low level of evidence (GRADE 2±). No recommendations could be provided using the GRADE® system for five of the questions, and for two of these questions expert opinions were given. After two rounds of discussion and an amendment, a strong agreement was reached for all the recommendations. Conclusion: Substantial agreement exists among experts regarding many strong recommendations for the improvement of practice concerning the use of muscle relaxants and reversal agents during anaesthesia. In particular, the French Society of Anaesthesia and Intensive Care (SFAR) recommends the use of a device to monitor neuromuscular blockade throughout anaesthesia.

BACKGROUND The end-expiratory occlusion test predicts fluid responsiveness in ventilated intensive care patients; however, its utility in the operating room is questioned. We assessed end-expiratory occlusion test in laparotomic surgery for predicting volume expansion. METHODS Forty-six patients were included in this study: stage 1 (n = 26) with an end-expiratory occlusion test of 15 seconds, followed by volume expansion, which consisted of 250 mL of colloid over 5 minutes and stage 2 (n = 20) with an end-expiratory occlusion test of 25 seconds followed by volume expansion. The last 10 patients had transdiaphragmatic pressures probed. Patients with an increase in cardiac index >15% after volume expansion were responders. Pulse pressure variation, stroke volume (SV) index, and cardiac index were analyzed. Receiver operating characteristic curves were established for changes in SV and pulse pressure induced by end-expiratory occlusion test and pulse pressure variation using the responders status for volume expansion as outcome. RESULTS A total of 44 (38%) volume expansions were deemed responders. After end-expiratory occlusion test of 15 seconds, no hemodynamic variables were significantly increased. After end-expiratory occlusion test of 25 seconds, SV index increased in responders (37.1 ± 8.8 mL/m after end-expiratory occlusion test of 25 seconds versus 35.7 ± 8.6 before; P < .0001). End-expiratory occlusion test could not discriminate responders from nonresponders. Only pulse pressure variation had significantly different area under the curve from that expected by chance (0.7 [0.57-0.81]; P = .002 for end-expiratory occlusion test of 15 seconds; and 0.78 [0.64-0.89]; P = .0001 for end-expiratory occlusion test of 25 seconds). After laparotomy, gastric pressure decreased significantly (4 [2.75-5] vs 2 [2-4] cm H2O; P = .0417); no difference was noticed in the transdiaphragmatic gradient. CONCLUSIONS End-expiratory occlusion test was not reliable to discriminate responders from nonresponders after volume expansion during laparotomic surgery.

Hypoalbuminemia in major cancer surgery can lead to postoperative short and long-term complications. Our study was designed to detect albumin variations in three major cancer surgeries: ovarian debulking (DBK), major abdominal gastrointestinal surgery (ABD), and major cervico-facial, or ear, nose and throat cancer surgery (ENT). Single-center prospective study inclusion criteria were non-emergency procedures scheduled to last at least five hours. We performed hourly perioperative monitoring of the patients’ albuminemia and hemoglobinemia. Electronic charts were followed for at least five years for survival analysis. Sixty-three patients were analyzed: 30 in the DBK group, 13 in the ABD group, and 20 in the ENT group. There was a significant difference in albumin decrease between the ENT group and the two others (−19% at six hours in the ENT group versus -49% in the debulking group and −31% in the ABD group (p < 0.05). There was no significant difference between the DBK and ABD groups. The decrease in hemoglobin was not significantly different between the groups, and no significant difference was observed in long-term survival. DBK and ABD surgery yielded significant hypoalbuminemia. Therefore, the extent of decrease in serum albumin is probably not the only etiology of the specific postoperative complications of these major surgeries. No significant difference was noticed in five-year mortality, and no correlation was found in relation to the degree of intraoperative albumin kinetics.

Opioid sparing is one of the new challenges in anesthesia and perioperative medicine. Opioid reduced anesthesia (ORA) is part of this approach, and it consists of a multimodal analgesia-associating non-opioid analgesic regional anesthesia to reduce intraoperative opioid requirements. Major cervicofacial oncologic surgery could specifically benefit from ORA, since it is known to generate intense and prolonged postoperative pain, with a high risk of pulmonary complications. Methods: This is a retrospective case-controlled study of 172 patients with major cervicofacial oncologic surgery. Group ORA (dexmedetomidine and lidocaine), n = 86, was compared to patients treated with standard opioid based anesthesia, Group control, n = 86. The main endpoint was to study perioperative opioid consumption and postoperative pain scores, and the secondary endpoint was to observe opioid related side effects. Results: The ORA group received 6.2 ± 3.1 mg morphine titration at the end of surgery, while the control group received 10.1 ± 3.7 mg p < 0.0001; there was no significant difference in post-operative analgesia requirements and pain scores between the groups. Intraoperatively, the ORA protocol yielded bradycardia in 4 persons, while in the control group, only 2 persons had bradycardia necessitating intervention, p < 0.05. Postoperatively, episodes of hypoxemia (50%) and the need for additional pressure-assisted ventilation (6%), was significantly different in the ORA group than in the control group (70% and 19%), p < 0.05. There was no difference between the two groups for the incidence of nausea and vomiting, ileus, or postoperative delirium. Discussion: ORA was not associated with a decrease in postoperative pain and opioid requirement, but possibly reduced the incidence of hypoxemia and the use of additional pressure-assisted ventilation, although we cannot rule out confounding factors. The possible benefits of ORA remain to be demonstrated by prospective studies.

Introduction: Unintended postoperative hypothermia frequently occurs upon arrival in the post anesthesia care unit (PACU). As part of our quality assurance program in anesthesia, we regularly monitor the incidence of this complication through our anesthesia information management system (AIMS). In this case-controlled retrospective study, our goal was to detect the incidence of unintended severe hypothermia in our breast surgery cancer patients, and subsequently to analyze the consequence of this complication in terms postoperative cutaneous infection, as well as its impact on further complementary treatment, such as radiotherapy and chemotherapy. Methods: This study was a retrospective analysis conducted through our AIMS system from 2015 through 2019, with extraction criteria based on year, type of surgery (breast), and temperature upon arrival in PACU. A tympanic temperature of less than 36 °C was considered to indicate hypothermia. Severe hypothermia was considered for patients having a temperature lower than 35.2 °C (hypothermic) (n = 80), who were paired using a propensity score analysis with a control group (normothermic) (n = 80) of other breast cancer surgery patients. Extracted data included time of surgery, sex, age, ASA status, and type and duration of the intervention. Results: The mean incidence of hypothermia was 21% from 2015 through 2019. The body mass index (BMI) was significantly lower in the hypothermia group before matching, 23.5 ± 4.1 vs. 26.4 ± 6.1 kg/m2 in normothermic patients (p &lt, 0.05). The hypothermia group also had significantly fewer monitoring and active warming devices. No difference was noted for wound complications. Time to complementary chemotherapy and or radiotherapy did not differ between groups (52 ± 21 days in group hypothermia vs 49 ± 22 days in the control group). Conclusion: Severe intraoperative hypothermia remains an important quality assurance issue in our breast surgery cancer patients, but we could not detect any long-term effect of hypothermia.

In this case a cervico facial cancer patient scheduled for tracheostomy followed by an endoscopy, and known to have a pacemaker, had hemodynamic instability at the start of general anaesthesia which lasted several hours. The anaesthetist in charge used the magnet to override the pace maker which did not respond. Indeed, it was a leadless pacemaker. These devices will be used more frequently and should be carefully scrutinized at the anaesthetic consultation.

Introduction Hypnosis has been reported to decrease pain and anxiety in surgical context, but data studying its impact on patient experience using a validated scale are scarce. In the present study, we assessed the effect of an audio hypnosis session on patient satisfaction during venous access port implantation under local anaesthesia in adult cancer patients using the EVAN-LR Score. Methods After informed consent, patients were randomised to receive either hypnosis or standard care. The hypnosis group listened to a 26 minutes recorded audio hypnosis session through the ongoing implantation procedure. The primary outcome was the result of the EVAN-LR questionnaire, assessing perioperative experience in patients undergoing anaesthesia without loss of consciousness. This score describes a global index and 5 dimensions of experience: comfort, pain attention, information and waiting. It is scaled from 0 to 100 with 100 indicating the best possible level of satisfaction. Secondary outcomes included patient's anxiety, heart rate before and after procedure, procedure duration and several Visual Analogic Scale to match EVAN-LR dimensions. Results Overall, 148 patients were enrolled in the study. The global index of Evan-LR was significantly higher in the hypnosis session group (78 ± 14) compared to the standard care group (71 ± 17) (P = 0.006). No difference was reported in secondary outcomes. Conclusion A recorded audio hypnosis session during subcutaneous venous port implantation under local anaesthesia in cancer patients significantly improved patient satisfaction.

Objective To compare cardiac index (CI) between Proaqt/PulsioFlex® and oesophageal Doppler (OD) and the ability of the PulsioFlex® to track CI changes induced by fluid challenge and secondly to assess the impact of the time interval between two auto-calibrations of PulsioFlex® on the accuracy of the measured CI. Methods In a single hospital, 49 intermediate-risk oncologic abdominal surgery patients were included in an observational study. We measured the cardiac Index (CI) provided by OD and by the Proaqt/PulsioFlex® before and after internal calibration, which were performed randomly at specific intervals after the initial one (30, 60, 90 and 120 min). The ability to track fluid responsiveness was evaluated by measuring stroke volume variation, pulse pressure variation (PPV) and CI before and after a 250 ml fluid challenge and assessed by a receiver operating characteristic curve analysis. Results The percentages of error before calibration were 51, 58, 82, 81% for 30, 60, 90 and 120 min, they were 39, 57, 65, and 54% after calibration. Trending ability is assumed by a 93% concordance rate after applying a 15% exclusion zone. The trend interchangeability rate was 13.75%. The area under the curve for fluid responsiveness measured by PPV and SVV PulsioFlex were respectively 0.67 [0.57–0.77], P Conclusions The Proaqt/Pulsioflex® system is not equivalent to OD for haemodynamic monitoring during non-vascular abdominal surgery in intermediate-risk patients. More studies are required to define the effect of the auto-calibration on the system.

Objective: Remifentanil, a rapid onset rapid offset synthetic opioid and potent analgesic, is often used for procedural conscious sedation in spontaneous ventilation, especially when delivered in target controlled infusion (TCI), which allows precise titration. We assessed efficacy, tolerance, and adverse events related with the use of remifentanil TCI during various procedures . Design: Prospective, observational . Setting: Two teaching hospitals . Patients: We enrolled 434 patients undergoing procedures suitable for conscious sedation . Interventions: The following procedures considered suitable were included: interventional radiology, gastrointestinal (GI) endoscopy, interventional cardiology, and peripheral dermatology. Sedation options were determined during the preoperative anesthesia assessment . Main outcome measures: Demographics were recorded as well as success rate, remifentanil dosage, pain scores, respiratory or cardiovascular events, and patient and operator satisfaction . Results: The procedure was successful in 429 patients (99 percent), canceled in four patients because of agitation, apnea, desaturation, and converted to general anesthesia in two for major pain. The maximal remifentanil target was around 2-3 ng/ml for most procedures, but it was 3-5 ng/ml for GI endoscopy and urology. A total of 172 patients (40 percent) had bradypnea < 8 min − 1, but only 26 (6 percent) had hypoxemia < 90 percent. Eighteen patients (4 percent) required mandibular luxation, and twelve needed face mask ventilation. There were no major cardiovascular adverse events . Conclusions: Remifentanil TCI is a suitable protocol for procedural sedation, but respiratory depression is a permanent concern. This risk requires equipped environment and competent medical personnel on hand to adjust the target before hypoxemia occurs. Respiratory rate monitoring, based on capnography or thoracic impedance is of a great help in anticipating this threat .

Introduction: This study was designed to compare the Datex neuromuscular transmission (NMT) kinemyography (NMTK) device with the TOFscan (TS) accelerometer during the onset and recovery of neuromuscular blockade. Patients and methods: This prospective study included adult patients who were scheduled to undergo elective surgery with general anesthesia and orotracheal intubation. The TS accelerometer was randomly placed at the adductor pollicis on one hand, and the NMTK was placed on the opposite arm. Anesthesia was initiated with remifentanil target-controlled infusion (TCI) and 2.0–3.0 mg/kg of propofol. Thereafter, 0.5 mg/kg of atracurium or 0.6 mg/kg of rocuronium was injected. If needed, additional neuromuscular blocking agents were administered to facilitate surgery. First, we recorded the train of four (TOF) response at the onset of neuromuscular blockade to reach a TOF count of 0. Second, we recorded the TOF response at the recovery of neuromuscular blockade to obtain a T4/T1 90% by both TS and NMTK. Results: There were 32 patients, aged 38–83 years, with the American Society of Anesthesiologists (ASA) Physical Status Classification I–III included and analyzed. Surgery was abdominal, gynecologic, or head and neck. The Bland and Altman analysis for obtaining zero responses during the onset showed a bias (mean) of 2.7 s (delay) of TS in comparison to NMTK, with an upper/lower limit of agreement of [104, −109 s] and a bias of 36 s of TS in comparison to NMTK, with an upper/lower limit of agreement of [−21.8, −23.1 min] during recovery (T4/T1 &gt, 90%). Conclusions: Under the conditions of the present study, the two devices are not interchangeable. Clinical decisions for deep neuromuscular blockade should be made cautiously, as both devices appear less accurate with significant variability.

Objective To assess the effect of dexamethasone on complications or all cause mortality after major non-cardiac surgery. Design Phase III, randomised, double blind, placebo controlled trial. Setting 34 centres in France, December 2017 to March 2019. Participants 1222 adults (>50 years) requiring major non-cardiac surgery with an expected duration of more than 90 minutes. The anticipated time frame for recruitment was 24 months. Interventions Participants were randomised to receive either dexamethasone (0.2 mg/kg immediately after the surgical procedure, and on day 1) or placebo. Randomisation was stratified on the two prespecified criteria of cancer and thoracic procedure. Main outcomes measures The primary outcome was a composite of postoperative complications or all cause mortality within 14 days after surgery, assessed in the modified intention-to-treat population (at least one treatment administered). Results Of the 1222 participants who underwent randomisation, 1184 (96.9%) were included in the modified intention-to-treat population. 14 days after surgery, 101 of 595 participants (17.0%) in the dexamethasone group and 117 of 589 (19.9%) in the placebo group had complications or died (adjusted odds ratio 0.81, 95% confidence interval 0.60 to 1.08; P=0.15). In the stratum of participants who underwent non-thoracic surgery (n=1038), the primary outcome occurred in 69 of 520 participants (13.3%) in the dexamethasone group and 93 of 518 (18%) in the placebo group (adjusted odds ratio 0.70, 0.50 to 0.99). Adverse events were reported in 288 of 613 participants (47.0%) in the dexamethasone group and 296 of 609 (48.6%) in the placebo group (P=0.46). Conclusions Dexamethasone was not found to significantly reduce the incidence of complications and death in patients 14 days after major non-cardiac surgery. The 95% confidence interval for the main result was, however, wide and suggests the possibility of important clinical effectiveness. Trial registration ClinicalTrials.gov NCT03218553 .

Backgrounds Procedures for Postoperative Nausea and Vomiting (PONV) prevention are mostly based on identification of the risk factors before administering antiemetic drugs. The purpose of this study was to evaluate the impact of the extended use of antiemetic on the PONV in the Postanesthetic Care Unit (PACU). Methods Two separate 4-year periods (2007-2010, P1, and (2015-2018, P2) were evaluated. During P1, the protocol consisted of dexamethasone and droperidol for patients with a locally adapted high PONV score, followed by ondansetron for rescue in the PACU. For Period 2, dexamethasone (8 mg) and ondansetron (4 mg) were administered in patients under general or regional anesthesia, or sedation longer than 30 minutes, while droperidol (1.25 mg) in rescue was injected in cases of PONV in the PACU. An Anesthesia Information Management System was used to evaluate the intensity score of PONV (1 to 5), putative compliance, sedation, and perioperative opioid consumption upon arrival in the PACU. Results A total of 27,602 patients were assessed in P1 and 36,100 in P2. The administration of dexamethasone and ondansetron increased several fold (p < 0.0001). The high PONV scores were more improved in P2 than in P1, with scores (3+4+5) for P1 vs. P2, p < 0.0001. Overall, 99.7% of the patients in P2 were asymptomatic at discharge. Morphine consumption decreased from 6.9±1.5 mg in P1 to 3.5 ± 1.5 mg in P2 (p < 0.0001). Discussion The extension of pharmacological prevention of PONV was associated with a decrease in the intensity of severe PONV. However, uncertainty regarding confounding factors should not be ignored. IRB nº 92012/33465

Background: Opioid dependency is becoming increasingly common among surgical patients with cancer, and can lead to inadequate pain relief during the initial postoperative period. No guidelines are currently available for the management of perioperative and postoperative morphine administration in these patients. As a first approach, the authors assessed the opioid requirements of these patients during the early postoperative period. Methods: A group of 35 consecutive surgical patients with cancer on opioid therapy (opioid-dependent group) for cancer pain were compared to a matched group of 44 surgical opioid-naive patients (control group). All patients underwent major head and neck or abdominal surgery. The following parameters were recorded and compared: preoperative and postoperative morphine consumption, patient-controlled analgesia records and Visual Analog Scale scores, intraoperative remifentanil and desflurane consumption, Bispectral Index monitoring values, heart rate, and blood pressure. Results: Remifentanil requirements were significantly higher (1.4-fold) in the opioid-dependent group compared to the control group (p < 0.05). On postoperative day 1, morphine requirements were significantly higher in the opioid-dependent group (2.3-fold) compared to the control group (p < 0.05). Baseline heart rate was significantly higher in the opioid-dependent group and this difference remained significant during surgery, no significant difference in blood pressure was observed between the two groups. Conclusion: This study shows a 40 percent increase of intraoperative remifentanil requirements in opioid-dependent patients during cancer surgery. Morphine requirements during the postoperative period were increased by up to 140 percent.

Background: This study compared the properties of propofol bolus for induction of general anaesthesia between proprietary and 3 generic formulations, to assess if solvent differences had clinically relevant consequences on effi cacy or side effects. Many studies have investigated different formulations of propofol for side effects, in this study we also focused on effi cacy of different formulations for induction of general anesthesia. Methods: 146 patients scheduled for general anaesthesia received for induction one of the propofol formulations available in our country i.e. 35 had Propofol® Fresenius, 33 Propofol Dakota Pharm®, 40 Propofol Lipuro®, 38 Diprivan® injected in a peripheral venous catheter, and preceded by sufentanil 0.2 μg.kg-1. Airway control was based on intubation (n = 90, facilitated by atracurium), or laryngeal mask (n = 56). Effi cacy was assessed by induction dose, ease of face mask ventilation and airway device insertion. Pain on injection, rash, or myoclonies were recorded as side effects. Propofol formulations were compared by Anova or Chi 2 test. Results: Expected hypnotic effects propofol injection were similar in the 4 groups, satisfying and consistent with previous publications. Pain on injection was present in 55% of patients (n = 81), mild in 36% (n = 54), and severe in 18% (n = 27). Myoclonies occurred in 4% of patients (n = 7) and local rash in 6% of patients (n = 10). Differences between formulations did not reach statistical signifi cance. Conclusion: The propofol formulations tested appeared similar on effi cacy, with minor differences regarding side effects. No formulation could suppress totally pain on injection and associated treatment as lidocaine should be widely used. Keywords: Pain with propofol; Pain on propofol injection; Propofol adverse effects

Sugammadex provides a rapid pharmacological reversal of aminosteroid, as well as fewer pulmonary complications, a better physiological recovery, and shorter stays in the postanesthetic recovery unit (PACU). This retrospective analysis of our Centricity anesthesia database in 2017–2019 assessed the efficiency of sugammadex in real-life situations in two groups of surgical cancer patients (breast and abdominal surgery) based on the extubation time, operating room exit time, and length of PACU stay. Overall, 382 anesthesia records (131 breast and 251 abdominal surgeries) were extracted for the pharmacological reversal of neuromuscular blockades by neostigmine or sugammadex. Sugammadex was used for reversal in 91 breast and 204 abdominal surgeries. Sugammadex use did not affect the extubation time, operating room exit time, or length of PACU stay. However, the time to reach a 90% train of four (TOF) recovery was significantly faster in sugammadex patients: 2 min (1.5–8) in breast surgery and 2 min (1.5–7) in abdominal surgery versus 10 (6–20) and 9 min (5–20), respectively, for neostigmine (p &lt, 0.05). Most patients who were reversed with sugammadex (91%) reached a TOF ratio of at least 90%, while 54% of neostigmine patients had a 90% TOF ratio recorded (p &lt, 0.05). Factors other than pharmacological reversal probably influence the extubation time, operating room exit time, or PACU stay, however, sugammadex reliably shortened the time so as to reach a 90% TOF ratio with a better level of reversal.

Anaesthesia Information Management Systems (AIMS) generate large amounts of data, which might be useful for quality assurance programs. This study was designed to highlight the multiple contributions of our AIMS system in extracting quality indicators over a period of 10years.The study was conducted from 2002 to 2011. Two methods were used to extract anaesthesia indicators: the manual extraction of individual files for monitoring neuromuscular relaxation and structured query language (SQL) extraction for other indicators which were postoperative nausea and vomiting (PONV), pain, sedation scores, pain-related medications, scores and postoperative hypothermia. For each indicator, a program of information/meetings and adaptation/suggestions for operating room and PACU personnel was initiated to improve quality assurance, while data were extracted each year.The study included 77,573 patients. The mean overall completeness of data for the initial years ranged from 55 to 85% and was indicator-dependent, which then improved to 95% completeness for the last 5years. The incidence of neuromuscular monitoring was initially 67% and then increased to 95% (P0.05). The rate of pharmacological reversal remained around 53% throughout the study. Regarding SQL data, an improvement of severe postoperative pain and PONV scores was observed throughout the study, while mild postoperative hypothermia remained a challenge, despite efforts for improvement.The AIMS system permitted the follow-up of certain indicators through manual sampling and many more via SQL extraction in a sustained and non-time-consuming way across years. However, it requires competent and especially dedicated resources to handle the database.

Introduction Quantitative neuromuscular monitoring is now widely recommended during anesthesia using neuromuscular blocking agents to prevent postoperative residual paralysis and its related complications. We compared the TOF-Watch SX™ accelerometer requiring initial calibration to the TOF-Scan™, a new accelerometer with a preset stimulation intensity of 50 mA not necessitating calibration. Study design This pilot, prospective, observational study included adults undergoing general anesthesia with endotracheal intubation and muscle relaxation, having both arms free during surgery. Accelerometers were set up randomly on each arm. Anesthesia was started with remifentanil and propofol before an intubation dose of atracurium or rocuronium. Train of four stimulation was performed every 15 s. Differences between measures were tested using Student's t -test and agreement assessed by Bland and Altman analysis. Results Thirty-two patients were included. During onset, a mean bias of −26 seconds with a limit of agreement from −172 to +119 seconds was observed between TOF-Watch SX™ and TOF-Scan™ to obtain 0 response to TOF. During recovery, TOF-Scan™ showed a significantly later recovery from 1 response to T4/T1 > 10%, but a bias of 0 minute and limits of agreement from −4 to +4 minutes for T4/T1 > 90% (NS). Conclusion These results suggest a poor agreement between the calibrated TOF-Watch SX™ and the fix intensity TOF-Scan™ for onset and early recovery of relaxation (i.e. deep neuromuscular blockade) but a good agreement for recovery to TOF 90%. Data are not interchangeable between the devices, but both can be useful to detect residual paralysis.

To compare cardiac index (CI) between Proaqt/PulsioFlexIn a single hospital, 49 intermediate-risk oncologic abdominal surgery patients were included in an observational study. We measured the cardiac Index (CI) provided by OD and by the Proaqt/PulsioFlexThe percentages of error before calibration were 51, 58, 82, 81% for 30, 60, 90 and 120min, they were 39, 57, 65, and 54% after calibration. Trending ability is assumed by a 93% concordance rate after applying a 15% exclusion zone. The trend interchangeability rate was 13.75%. The area under the curve for fluid responsiveness measured by PPV and SVV PulsioFlex were respectively 0.67 [0.57-0.77], P0.01 and 0.75 [0.47-0.66], which was not clinically relevant.The Proaqt/Pulsioflex

Background:The efficacy of local anesthetic wound infiltration for the treatment of acute and chronic postoperative pain is controversial and there are no detailed studies. The primary objective of this study was to evaluate the influence of ropivacaine wound infiltration on chronic pain after breast surgery.Methods:In this prospective, randomized, double-blind, parallel-group, placebo-controlled study, 236 patients scheduled for breast cancer surgery were randomized (1:1) to receive ropivacaine or placebo infiltration of the wound, the second and third intercostal spaces and the humeral insertion of major pectoralis. Acute pain, analgesic consumption, nausea and vomiting were assessed every 30 min for 2 h in the postanesthesia care unit and every 6 h for 48 h. Chronic pain was evaluated 3 months, 6 months, and 1 yr after surgery by the brief pain inventory, hospital anxiety and depression, and neuropathic pain questionnaires.Results:Ropivacaine wound infiltration significantly decreased immediate postoperative pain for the first 90 min, but did not decrease chronic pain at 3 months (primary endpoint), or at 6 and 12 months postoperatively. At 3 months, the incidence of chronic pain was 33% and 27% (P = 0.37) in the ropivacaine and placebo groups, respectively. During follow-up, brief pain inventory, neuropathic pain, and anxiety increased over time in both groups (P < 0.001) while depression remained stable. No complications occurred.Conclusion:This multicenter, prospective study shows that ropivacaine wound infiltration after breast cancer surgery decreased immediate postoperative pain but did not decrease chronic pain at 3, 6, and 12 months postoperatively.

Background: The level of sensory block in postoperative epidural analgesia has been correlated with conventional contrast epidurography in only one study, while low-dose CT scan epidurography with multiplanar reconstruction may be a better tool for this purpose. Objectives: The primary objective of this study was to evaluate, by CT imaging and digital multiplanar reconstruction, the spread and distribution of contrast medium injected into the epidural space through a catheter inserted in a low thoracic position for postoperative analgesia. Materials and Methods: Ten patients undergoing major abdominal cancer surgery with effective epidural analgesia were prospectively included at postoperative day three. Two consecutive boluses of 5 mL of a mixture of ropivacaine and contrast medium were injected at 15 minutes intervals into the epidural space. Multislice low-dose CT scan epidurography and an assessment of the sensory block were performed before and after injection of the second bolus. The primary objective was to assess the contribution of CT scan epidurography to predict a correlation between the level of sensory block and the spread of the contrast medium in the epidural space; the secondary objective was to determine the agreement between the two methods. Results: The spread of contrast material and the clinical sensory block significantly increased after the second injection (32%; P < 0.05). However, no highly significant correlation was observed between the two methods. A gap of two spinal segments of CT opacification was observed in two patients and was confirmed by clinical assessment. Conclusions: CT epidurography is not closely correlated with a clinical assessment of epidural block; thus, a clinical assessment of the sensory block is mandatory. The use of opioid analgesia in combination with local anesthetics may compensate for the lack of efficacy of local anesthetics alone.

Bayesian forecasting has been shown to improve the accuracy of pharmacokinetic/pharmacodynamic (PK/PD) models by adding measured values to a population model. It could be done in real time for neuromuscular blockers (NMB) using measured values of effect. This study was designed to assess feasibility and benefit of Bayesian forecasting during a rocuronium target-controlled infusion (TCI). After internal review board (IRB) approval and informed consent, 21 women scheduled for breast plastic surgery were included. Anesthesia was maintained with propofol, alfentanil, and controlled ventilation through a laryngeal mask. Rocuronium was delivered in TCI with Stanpump software and the Plaud population model. The target effect was 50% blockade until insertion of breast prosthesis; thereafter it was set to 0%. Response to train of four (TOF) at adductor pollicis was recorded using a force transducer. In ten patients, drug delivery was based on the population model. In the others, repeated measures values were entered in the software, and the PK model was adjusted to minimize the error in predicted effect. Model precision was compared between groups using mean prediction error and mean absolute prediction error. At target 50%, model accuracy was not improved with Bayesian adjustments; conversely, post-infusion errors were significantly decreased. The first two measures had the most influence on the model changes. Below clinical utility, such adjustments may be used to explore cofactors influencing interindividual and intraindividual variability in NMB dose-response relationship. Similar tools may also be developed for drugs in which a quantitative effect is available, such as electroencephalography (EEG) for hypnotics. Real-time Bayesian forecasting combining measured values of effect with a population model is suitable to guide NMB-agent delivery using Stanpump software.

Resume Objectifs Relever du dossier d’anesthesie tout item documentant la gestion des curares et de leurs effets en chirurgie viscerale. Type d’etude Etude prospective, observationnelle et multicentrique. Patients et methodes Un encodeur unique analysait 1453 dossiers de patients mis a disposition par neuf centres. Les releves concernaient trois periodes distinctes : induction/intubation de la trachee, entretien de la curarisation, retrait de la sonde d’intubation. La presence de 40 items etait recherchee. Resultats Pour l’intubation de la trachee, les grades de laryngoscopie et les conditions d’intubation etaient releves, dans 43 % (0–95) [moyenne generale (min–max intercentres)] et dans 11 % (0–97) des dossiers, respectivement. Un niveau de paralysie etait rapporte dans 23 % (0–96) des documents. Pour la periode d’entretien de la curarisation, la documentation d’un effet apparaissait dans 53 % (4–96) des dossiers. Des evaluations neuromusculaires precedant le retrait de la sonde d’intubation etaient retrouvees dans 43 % (12–89) des pratiques. L’adducteur du pouce etait concerne pour 30 % (1–89) de ces observations. Un niveau de decurarisation spontanee satisfaisant a dire de praticiens apparaissait dans 14 % (3–19) des documents. La decurarisation pharmacologique etait pratiquee chez 25 % (4–67) des patients avec une evaluation de son effet dans 8 % (0–58). Conclusion Dans l’echantillon etudie, la tracabilite de la gestion de la curarisation per anesthesique se revele variable tant sur le plan qualitatif que quantitatif. La mise a disposition d’un referentiel, dedie aux criteres de bonne documentation de la curarisation, est necessaire pour poursuivre le processus d’amelioration de ces pratiques specifiques aux utilisateurs d’agents curarisants.

As part of a quality assurance program, we assessed the trend of our analgesic consumption using our anesthesia database which include anesthesia and postanesthetic care records for all patients. In recent years, emphasis was made on anesthesia personnel to decrease postoperative opioid analgesic at the expense of non-opioid analgesics in order to decrease opioid related side effects. The following items were recorded: intraoperative opioid consumption, total morphine consumption, non-opioid analgesic consumption pain and sedation scores in the postoperative care unit (PACU). The database consisted of 57,967 patients for 9 consecutive years from 2002 to 2010, mean data exhaustivity was of 95%. Total morphine consumption per patient in the operative room and in the PACU decreased significantly from 11 ± 4 mg in year 2002 to 7 ± 3 mg in 2010, P #60; 0.05. In the intraoperative period, remifentanil/sufentanil ratio increased significantly from 33/67 to 87/13% of patients (P #60; 0.05) without affecting pain scores in the PACU. This multi-year trend shows a significant decrease in overall postoperative morphine consumption, in addition we showed that computerized database can easily follow the trend of analgesic consumption and can be used therefore as a powerful tool with easy access as part of a quality assurance program.

Background Catheter-related bladder discomfort (CRBD) is often reported to be stressful and resistant to conventional opioid therapy in the post anaesthesia care unit (PACU). Tolterodine or oxybutynin or gabapentin given orally 1 hour before induction reduce the incidence and severity of CRBD postoperatively. Nevertheless, side effects may occur with these drugs. Thus, preadministration of these different drugs should be selective in patients with predictors of moderate or severe CRBD. The goal of this study was to determine the incidence and predictors of early postoperative CRBD in post-anesthesia care unit. Methods We designed a prospective observational study in two teaching hospitals. Consecutive adult patients undergoing surgery under general anaesthesia necessitating intraoperative urinary catheterization were included during a 6-month period. Bladder discomfort was assessed with a simple four - step severity scale: no pain; mild pain (revealed only by interviewing the patient); moderate (a spontaneous complaint by the patient) and severe discomfort (agitation, loud complaints and attempt to remove the bladder catheter). Predictors of CRBD were identified by univariate and multivariate analysis. Results 164 patients were included, of which 47% complained of CRBD (mild CRBD: 20%; moderate or severe CRBD: 27%). Multivariate logistic regression analysis showed the diameter of the Foley catheter superior than 18 G Fr (OR = 2.2, CI95 [1.0–5.1], P = 0.06) and male gender (OR = 3.2, CI95 [1.0–10.5], P 0.06) to be independent predictors of moderate or severe CRBD in the PACU. Conclusion This observational study identified the incidence and predictive factors of moderate and severe CRBD in the PACU. Future studies are warranted to assess the impact of preoperative antimuscarinic drugs or Gabapentin on males or patients with 18 G Fr Foley catheters.

The repeated syncopes in case of head and neck cancer are a complication rarely described in the literature. They occur when the tumor invade the carotid sinus or the afferent fibers of the glossopharyngeal nerve. We report the case of a 62-year-old man presented episodes of syncope synchronous of a recurrent hypopharyngeal tumor scheduled for chemotherapy and gastrostomy. A computerized tomography showed a voluminous tumor expanded to the carotid and parapharyngeal spaces. After treatment by isporenaline chlorhydrate in intensive care unit, a pacemaker was implanted to prevent syncopes and allowed the beginning of the chemotherapy.

Resume Introduction Cette etude a ete realisee dans le cadre d’une demarche d’evaluation des pratiques professionnelles (EPP) afin d’encourager l’augmentation du taux de monitorage peroperatoire des curares. Methodes Apres accord du comite d’ethique local, nous avons evalue 200 dossiers informatises d’anesthesie au cours desquelles un curare non depolarisant a ete utilise. Les parametres suivants ont ete etudies : caracteristiques demographiques, durees d’anesthesie et de chirurgie, utilisation du monitorage neuromusculaire (NMT®), utilisation d’un antagoniste et qualite du NMT®. Les resultats ont ete soumis aux differents intervenants du service d’anesthesie au cours d’un staff EPP au decours duquel une procedure interne a ete elaboree : l’objectif etant que tous les malades curarises puissent beneficier du monitorage chiffre de la curarisation. Six mois plus tard, une autre evaluation a ete realisee sur 200 nouveaux dossiers en tenant compte des memes criteres, afin d’evaluer l’impact de l’EPP sur la pratique clinique. Resultats Le taux de monitorage qui etait de 67 % initialement est passe a 94 % (p Discussion Cette etude a montre que, dans le cadre d’une demarche EPP, le nombre de patients beneficiant du monitorage quantitatif systematique peut etre augmente de facon significative avec un impact reel sur la decurarisation.

Summary Background and objective We conducted a prospective double blind randomized study assessing ropivacaine end-of-surgery wound infiltration for pain relief in thyroid surgery after remifentanil-based intraoperative analgesia. Methods Fifty elective ASA I–II patients scheduled for thyroid surgery were included in this study. Balanced anesthesia was performed with propofol, remifentanil, N2O, isoflurane. Patients were randomized in two equal groups: ropivacaine (n = 25) and saline (n = 25) which respectively had end-of-surgery wound infiltration with 15 ml of ropivacaine 2% or the same volume of saline. Results Pain intensity, morphine requirement and the length of stay in PACU were significantly lower in ropivacaine group as compared to saline group (P Conclusions If remifentanil is used for intraoperative analgesia, end-of-surgery wound infiltration with 15 ml ropivacaine 2% is an efficient strategy to control postthyroidectomy pain.

Summary Introduction PostOperative Nausea and Vomiting (PONV)is a major side effect related to surgery and anesthesia. Our institution is equipped with Anesthesia Information Management System (AIMS). We used this database to assess and follow the effect of our quality assurance program for PONV. Methods Our AIMS system permits automatic storage of vital signs while other information are indexed by anesthesia providers and PACU personnel. Intra-operative and PACU events were extracted from a database by sequential query language (SQL) interrogation from year 2005 to 2010. A new prophylactic antiemetic protocol was issued for high-risk patients in our institution (dexamethasone, droperidol in the operating room and odansetron in the PACU) and initiated in 2006; in parallel, adjuvant measures influencing PONV were taken for anesthetic interventions. PONV scores and related medications, intra- and postoperative opioids and inhalational anesthetics consumption were extracted, and results were regularly shared with anesthesia providers and PACU personnel as part of quality assurance program. Results The study concerned 40,045 patients, exhaustivity or completeness was 70% in 2005 but reached 90% in 2010. PONV scores significantly improved during the years after the instauration of the new protocol (31% in 2005 vs. 13% in 2010). Concomitantly, morphine consumption and intra-operative nitrous oxide showed a steady decrease. No significant difference was noticed in the use of inhalational anesthetics. Conclusion Using our AIMS database, we indirectly monitored the effectiveness of our PONV protocol but also other possible component of a multimodal approach toward these side effects.

Background Patients undergoing free flap reconstruction after head and neck cancer may develop free flap complications. In the perioperative period, haemoglobin content and oxygen tissue saturation (StO2) measured directly on the free flap reflect peripheral tissue oxygenation. However, in this type of surgery, StO2 cannot always be applied directly or proximate to the free flap. The aim of this study was to assess the possible value of StO2 measured at the thenar eminence and other 24 hour perioperative factors on free flap complications. Methods Inclusion criteria corresponded to patients with head and neck cancer with free flap surgery in whom direct StO2 could not be monitored on the flap nor in its peripheral area. Patient characteristics and intraoperative data, such as haemoglobin and fluid management, were prospectively collected. StO2 was measured remotely on the thenar eminence. Data were collected for 24 hours and free flap complications were recorded for up to 15 days after surgery. Patients were thereafter classified into two groups: with or without free flap complications and the data were compared in consequence. Results Forty consecutive patients were prospectively included. Ten patients had postoperative free flap complications and were compared to the 30 other patients without complications. The haemoglobin level at the reperfusion of the flap: (AUC 0.80 [0.65–0.91], threshold 9.9 g/dL, P Conclusion In head and neck complex oncologic reconstructive surgery, haemoglobin and BMI were the most sensitive tools for predicting postoperative free flap complications, while thenar eminence StO2 was not.

Background The intubating laryngeal mask airway (ILMA) was designed using the characteristics of healthy-weight subjects but was shown to be an effective airway device in morbidly obese patients. The authors compared airway management quality in morbidly obese and lean patients with use of the ILMA. Methods Fifty morbidly obese and 50 lean patients (mean body mass indexes, 42 and 27 kg/m, respectively) were enrolled in this prospective study. After induction of general anesthesia, characteristics of airway management were judged on safety and efficiency parameters, including success rate at ventilation and intubation and airway management quality criteria, such as the number of patients who required adjustment maneuvers, the number of failed tracheal intubation attempts, the total duration of airway management, and an overall difficulty visual analog scale score. Results The ILMA was successfully inserted and adequate ventilation through the ILMA was achieved in all 100 patients. The success rates of tracheal intubation through the ILMA were similar in obese and lean patients (96% and 94%, respectively). The numbers of failed blind tracheal access attempts and patients who required airway-adjustment maneuvers were significantly reduced in obese patients as compared with lean patients. Four obese patients experienced transient episodes of oxygen desaturation (oxygen saturation < 90%) before adequate bag ventilation was established with the ILMA. Conclusion The authors confirmed that the ILMA was an efficient airway device for airway management of both lean and obese patients. In the conditions of this study, the authors observed that airway management with the ILMA was simpler in obese patients as compared with lean patients.

Background Management strategies conceived to improve patient safety in anesthesia have rarely been assessed prospectively. The authors undertook a prospective evaluation of a predefined algorithm for unanticipated difficult airway management. Methods After a 2-month period of training in airway management, 41 anesthesiologists were asked to follow a predefined algorithm for management in the case of an unanticipated difficult airway. Two different scenarios were distinguished: "cannot intubate" and "cannot ventilate." The gum elastic bougie and the Intubating Laryngeal Mask Airway (ILMA) were proposed as the first and second steps in the case of impossible laryngoscope-assisted tracheal intubation, respectively. In the case of impossible ventilation or difficult ventilation, the IMLA was recommended, followed by percutaneous transtracheal jet ventilation. The patient's details, adherence rate to the algorithm, efficacy, and complications of airway management processes were recorded. Results Impossible ventilation never occurred during the 18-month study. One hundred cases of unexpected difficult airway were recorded (0.9%) among 11,257 intubations. Deviation from the algorithm was recorded in three cases, and two patients were wakened before any alternative intubation technique attempt. All remaining patients were successfully ventilated with either the facemask (89 of 95) or the ILMA (6 of 95). Six difficult-ventilation patients required the ILMA before completion of the first intubation step. Eighty patients were intubated with the gum elastic bougie, and 13 required a blind intubation through the ILMA. Two patients ventilated with the ILMA were never intubated. Conclusion When applied in accordance with a predefined algorithm, the gum elastic bougie and the ILMA are effective to solve most problems occurring during unexpected difficult airway management.

Background Mivacurium is potentiated by pancuronium to a much greater extent than other relaxants. In a previous investigation we suggested that this potentiation could be due to the ability of pancuronium to inhibit plasma cholinesterase activity, but we did not measure plasma concentrations of mivacurium. In the current study we performed a pharmacokinetic analysis by measuring the plasma concentration of mivacurium when preceded by administration of a low dose of pancuronium. Methods After induction of general anesthesia with propofol and fentanyl and orotracheal intubation, 10 patients (pancuronium-mivacurium group) received 15 microg/kg pancuronium followed 3 min later by 0.1 mg/kg mivacurium, whereas 10 other patients (mivacurium group) received saline followed by 0.13 mg/kg mivacurium 3 min later. Plasma cholinesterase activity was measured before and 3 and 30 min after pancuronium dosing in the pancuronium-mivacurium group and was measured before and after administration of saline in the mivacurium group. Arterial plasma concentrations of mivacurium and its metabolites were measured at 0.5, 1, 1.5, 2, 4, 10, 20, and 30 min after injection. Neuromuscular blockade was assessed by mechanomyography. Results Plasma cholinesterase activity decreased by 26% in the pancuronium-mivacurium group 3 min after injection of pancuronium (P < 0.01) and returned to baseline values 30 min later; however, no significant variation was observed in the mivacurium group. The clearances of the two most active isomers (Cis-Trans and Trans-Trans) were lower in the pancuronium-mivacurium group (17.6 +/- 5.1, 14.7 +/- 5.3 ml. min-1. kg-1, respectively) than in the mivacurium group (32.4 +/- 20.2, 24.8 +/- 13.5 ml. min-1. kg-1; P < 0.05). Conclusions A subparalyzing dose of pancuronium decreased plasma cholinesterase activity and the clearance of the two most active isomers of mivacurium. Pancuronium potentiates mivacurium more than other neuromuscular blocking agents because, in addition to its occupancy of postsynaptic acetylcholine receptors, it slows down the hydrolysis of mivacurium.

Volatile anesthetic agents potentiate neuromuscular blockade, but the magnitude of potentiation appears to be time dependent. The time course of this interaction was studied by measuring mivacurium infusion rates during sevoflurane, isoflurane and propofol anesthesia.After informed consent, anesthesia was induced in 48 ASA physical status I-II adults with propofol, fentanyl and mivacurium 0.25 mg.kg(-1) and maintained with N(2)O (60%) and one of the three agents chosen at random: sevoflurane 1.9%; isoflurane 1.2%; or propofol 100-150 microgram.kg(-1).min(-1). Train-of-four stimulation was applied every 15 sec to the ulnar nerve. Neuromuscular blockade was monitored with accelerometry. At 5% recovery of the first twitch (T1), a mivacurium infusion was started and adjusted every five minutes to maintain 90-95% T1 depression.The time to 5% T1 recovery after the initial dose was similar in all groups (13-15 min). Fifteen minutes after the start of the infusion mivacurium requirements were greater (P0.05) in the propofol group (7.5 +/- 1.7 microgram.kg(-1).min(-1); mean +/- SD) than in either isoflurane (4.7 +/- 1.6 microgram.kg(-1).min(-1)) or sevoflurane (4.5 +/- 1.5 microgram.kg(-1).min(-1)) group. Then, the rate remained stable for propofol (6.2 +/- 1.4 microgram.kg(-1).min(-1) after 90 min of infusion) while it decreased with isoflurane to 2.9 +/- 1.6 microgram.kg(-1).min(-1) at 90 min (P0.05 vs propofol) and to 1.4 +/- 1.0 microgram.kg(-1).min(-1) in the sevoflurane group (P0.05 vs propofol and isoflurane).Sevoflurane and isoflurane do not prolong the effect of a bolus dose of mivacurium, but potentiation increases with time from 30-105 min of exposure. This interaction is greater with sevoflurane than isoflurane.