Increased detection of the HIV-1 reverse transcriptase M184V mutation using mutation-specific minority assays in a UK surveillance study suggests evidence of unrecognized transmitted drug resistance.

OBJECTIVES: The aim of the study was to estimate the levels of transmitted drug resistance (TDR) in HIV-1 using very sensitive assays to detect minority drug-resistant populations. METHODS: We tested unlinked anonymous serum specimens from sexual health clinic attendees, who had not received an HIV diagnosis at the time of sampling, by both standard genotyping and using minority detection assays. RESULTS: By standard genotyping, 21 of 165 specimens (12.7%) showed evidence of drug resistance, while, using a combination of standard genotyping and minority mutation assays targeting three commonly observed drug resistance mutations which cause high-level resistance to commonly prescribed first-line antiretroviral therapy (ART), this rose to 32 of 165 (19.4%). This increase of 45% in drug resistance levels [95% confidence interval (CI) 15.2-83.7%; P=0.002] was statistically significant. Almost all of this increase was accounted for by additional detections of the M184V mutation. CONCLUSIONS: Future surveillance studies of TDR in the United Kingdom should consider combining standard genotyping and minority-specific assays to provide more accurate estimates, particularly when using specimens collected from chronic HIV infections in which TDR variants may have declined to low levels.

Dose-response effect of serum butyrylcholinesterase activity after clinical doses of pancuronium.

INTRODUCTION: Low-dose pancuronium is known to affect serum cholinesterase activity (BChE); however, the dose-response effect of clinical doses of pancuronium on BChE has not been investigated. METHODS: Thirteen ASA I-II patients scheduled for elective surgery requiring muscle relaxation were enrolled in this study. All patients had normal BChE before surgery. Incremental doses of pancuronium (10, 20, 50, and 100 microg/kg) were injected in accordance with surgical needs every 45 min. BChE was measured 3 min after injection by an automatic colorimetric method. RESULTS: BChE decreased significantly in all except one patient in comparison to the baseline (P < 0.05). However all values remained within normal clinical range. A dose of 100 microg/kg yielded significant decrease in comparison to 10 microg/kg but not to other dosages. Linear regression was not significant for the dose-response relationship (P = 0.05). CONCLUSION: After clinical incremental doses of pancuronium, BChE remained within clinical range.

Rescue transtracheal jet ventilation during difficult intubation in patients with upper airway cancer.

INTRODUCTION: The failure rates of intubation and/or mask ventilation are higher in patients with neck or upper airway disease. To ensure oxygenation, rescue trans-tracheal jet ventilation (RTTJV) may be used. In this critical situation, a high rate of complications has been reported. The aim of this study was to report RTTJV performed by a jet ventilator with an end-expiratory pressure control in an experienced institution. PATIENTS AND METHODS: From a computerised database of 63,905 anaesthesia cases, the anaesthetic reports of patients who underwent emergency RTTJV during intubation were studied retrospectively. The following information were analysed: anaesthetic procedures, data from the monitoring: lowest SpO2, duration of SpO2<90%, and complications. Success of emergency RTTJV was defined when SpO2 was>90% under jet ventilation. RESULTS: RTTJV was used in 31 patients, of whom 26 had upper airway cancer, (pre-treatment, n=9, post-treatment, n=17). Difficult intubation was anticipated in 15 out of 31 cases including six fiber-optic-aided intubations under spontaneous ventilation. RTTJV was effective in all cases with quick restoration of oxygenation (SpO2>90%). During jet ventilation, final airway control was performed either by oral intubation (n=25) or tracheotomy (n=1) in a short delay (mean: 8.1±1.7min). Subcutaneous emphysema was observed in one case without pneumothorax. CONCLUSION: RTTJV with end-expiratory pressure control allowed oxygenation during difficult intubation, with a low rate of complications.

Postoperative pain scores and analgesic requirements after thyroid surgery: comparison of three intraoperative opioid regimens.

PURPOSE: This study was designed to compare the effect on postoperative pain, opioid consumption and the length of stay in postoperative care unit (PACU) after three different intraoperative analgesic regimens in thyroid surgery. METHODS: Seventy five patients were enrolled into the study and assigned to one of three groups, fentanyl, sufentanil or remifentanil (n=25 for each group). Before the end of surgery, paracetamol 1 gr and nefopam 20 mg was also administered in all patients. Pain scores, opioid demand and the length of stay in PACU were assessed in a blind manner. RESULTS: Post operative pain scores were significantly lower in the fentanyl and sufentanil groups compared to remifentanil group (55 +/- 15, and 60 +/- 10 versus 78+/- 12, P < 0.05). Patients in the remifentanil group stayed longer in the PACU 108+/- 37 min versus 78+/-31 and 73 +/- 25 min, (P< 0.05). CONCLUSION: After remifentanil based analgesia, anticipation of postoperative pain with opioid analgesic appears mandatory even for surgery rated as being moderately painful, otherwise longer opioid titration due to higher pain scores might delay discharge time.

[Effectiveness of low mivacurium if its injection is postponed by a non-invasive pressure determination on the homolateral arm]. / L'efficacité du mivacurium baisse si son injection est retardée par une prise de pression non-invasive sur le bras homolatéral.

OBJECTIVE: We assessed the neuromuscular characteristics of 0.2 mg.kg-1 of mivacurium while its injection was concomitant to a non invasive blood pressure measurement in the ipsilateral arm. PATIENTS: Thirty-one patients ASA I-II were randomized into two groups. Group cuff (n = 15) and Group control (n = 16). METHODS: General anaesthesia was induced with fentanyl, thiopentone and mivacurium in all patients, however in the cuff group, measurement of non invasive blood pressure was performed immediately after the injection of mivacurium. Comparison was made on neuromuscular blockade of the adductor pollicis (AP) by mechanomyography, and intubating conditions which were guided by the visual estimation of the orbicularis oculi's (OO) response. RESULTS: In the cuff group, six out of 15 patients did not have complete blockade at the OO against one out of 16 in the control group, (Fisher exact test p < 0.05). Intubation time was significantly delayed in the cuff group, 201 +/- 66 s versus 123 +/- 32 s in the control group, (t test p < 0.001). The maximum neuromuscular blocking effect at the AP was significantly greater in the control group 99 +/- 2% against 89 +/- 7% in the cuff group, (t test p < 0.01). The onset of maximum blockade at the AP was longer in the cuff group 294 +/- 40 s versus 179 +/- 92 s, (t test p < 0.001] in the control group. Time to 25% recovery was shorter in the cuff group 16 +/- 3 min versus 20 +/- 5 min, in the control group (t test p < 0.05). CONCLUSION: This study suggests that non invasive blood pressure measurement of the ipsilateral arm, concomitant to the injection of mivacurium decreases the potency of mivacurium. This finding is mostly explained by the early hydrolysis of mivacurium in the plasma of the excluded arm.

[Sensitivity to atracurium in the lateral abdominal muscles] . / Sensibilité à l'atracurium des muscles abdominaux latéraux.

OBJECTIVE: To study the effect of atracurium on the electromyographic activity of the lateral abdominal muscles and adductor pollicis in anaesthetized subjects. STUDY DESIGN: Prospective, comparative, open study. PATIENTS AND METHODS: Sixteen patients, ASA physical status 1 or 2, undergoing elective orthopaedic surgery under general anaesthesia were studied. Anaesthesia was induced with propofol/fentanyl and orotracheal intubation performed after glottic local anaesthesia without using muscle relaxant. Anaesthesia was maintained with isoflurane/nitrous oxide/oxygen and fentanyl reinjections. Supramaximal percutaneous stimulations in a simple twitch mode (0.1 Hz) were applied at the 9th-10th intercostal nerve on the posterior axillary line and at the ulnar nerve at the wrist. The electromyographic responses were registered using skin surface electrodes, placed on the D9-D10 dermatome in regard of the lateral abdominal muscles and of the thenar muscles. After a single bolus dose of atracurium 0.5 mg.kg-1, the following parameters were studied: the maximum effect (Emax), the time for obtaining Emax (Delay) and the recovery time of 5, 10, 25, 50, 75 and 100% of the control neuromuscular response (T5, T10, T25, T50, T75, T100). RESULTS: The dose of 0.5 mg.kg-1 of atracurium induced 100% block in both lateral abdominal muscles and adductor pollicis. Lateral abdominal muscles blockade had faster onset (136 +/- 4 s versus 205 +/- 29 s) and shorter recovery, T5, T10, T25, T50, T75 and T100 were significantly (p < 0.05) shorter than at the adductor pollicis. CONCLUSION: Lateral abdominal muscles blockade have faster onset and recovery than adductor pollicis.

[Recurrent syncope in head and neck cancer: a case report]. / Tumeur ORL responsable de syncopes à répétition: cas clinique.

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.

Airway fire during tracheostomy.

INTRODUCTION: Twenty-five cases of airway fire during tracheostomy have been reported in the literature. The authors describe a case observed in their centre 3 years ago, discuss the causes and preventive management and propose guidelines for prevention of this complication. CASE REPORT: A 66-year-old woman was intubated and ventilated with 100% oxygen during general anaesthesia for tracheostomy. On opening the trachea by monopolar diathermy, the oxygen present in the endotracheal tube caught fire, inducing combustion of the tube spreading to the lower airways. This airway fire was responsible for severe acute respiratory failure and the formation of multiple laryngotracheal stenoses. DISCUSSION: Combustion of the endotracheal tube due to ignition of anaesthetic gases induced by the heat generated by diathermy is responsible for airway fire. These various phenomena are discussed. Prevention is based on safety measures and coordination of surgical and anaesthetic teams.

Predictors of catheter-related bladder discomfort in the post-anaesthesia care unit.

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.

[Reporting of muscle relaxant effects in anaesthesia files concerning visceral surgery - a observational and multicenter study]. / Traçabilité de la gestion de l'utilisation des curares dans le dossier d'anesthésie en chirurgie viscérale : une étude observationnelle et multicentrique.

OBJECTIVES: To report any item documenting the peroperative muscle relaxant effects management in anaesthesia files issued from visceral surgery processes. TYPE OF STUDY: Prospective, observational and multicenter. PATIENTS AND METHODS: A single operator analysed 1453 files proposed by nine anaesthetists' teams. The items selected concerned three periods: induction/tracheal intubation, paralysis maintenance, tracheal extubation. Reporting of 40 categories of items was studied. RESULTS: Items related to laryngoscopy and intubation conditions were observed in 43% (0-95) [general average (intercentres min-max)] and in 11% (0-97) of the files, respectively. At least one level of paralysis was reported in 23% (0-96) of the files. For the paralysis maintenance, documentation of an effect appeared in 53% (4-96) of the documents. Neuromuscular assessments preceding the tracheal extubation were retrieved in 43% (12-89) of the notes. Adductor pollicis was concerned for 30% (1-89) of these observations. Detection of level of spontaneous paralysis offset, satisfying to the local standard, appeared in 14% (3-19) of the documents. Pharmacological reversal was noted for 25% (4-67) of the patients; the assessment of the effects so produced was reported in 8% (0-58). CONCLUSION: In the studied collection, the traceability of the peranaesthetic curarization management appears variable on both qualitative and quantitative levels. The emergence of a dedicated guideline - defining the criteria for producing a good documentation of the muscle relaxant use - becomes necessary to secure these practices for all physicians using muscle relaxants.

Incidence of severe postoperative pain after cancer surgery despite intraoperative anticipation: a case controlled study.

BACKGROUND AND METHODS: Anticipating postoperative pain is a routine practice in our institution. As part of a quality assurance program we used our computerized anesthetic record system database to evaluate incidence of patients having very severe postoperative pain (grade 4 on a subjective pain scale ranging from 0 to 4) in the Post Anesthetic Care Unit during a two year period. These patients were compared to a control group matched on age, type and date of surgery. Demographic characteristics, type and duration of the surgery, preoperative and intra-operative medications were compared between groups. RESULTS: 78 patients out of 12,510 (0.6%) with a pain score of 4 were compared to another group of 78. No significant difference was observed with regards of demographic characteristics, duration, type of surgery, and operative pain medications. Pain scores and morphine consumption were significantly higher in the cases study group in comparison to the controlled group, 4 vs 1.6+/-1.1, (p<0.05) and 13.2+/-6 vs. 6.9+/-7mg (p<0.05). Patients in the cases study group had significantly more preoperative psychoactive medication: antidepressant and benzodiazepine 13 vs. 2, (p<0.05). CONCLUSION: The incidence of severe postoperative pain scores were less than 1% in our institution. In patients with preoperative opioid treatment, adaptation of analgesic treatment has probably prevented the occurrence of severe pain. Multimodal anticipation of postoperative pain should remain mandatory while efforts should focus to identify such patients before surgery.

[Impact of a quality assurance program on the use of neuromuscular monitoring and reversal of muscle relaxants]. / Impact d'une démarche d'évaluation des pratiques professionnelles sur l'utilisation du monitorage de la curarisation et l'antagonisation des curares.

INTRODUCTION: As part of a quality assurance in the anaesthesia department, this study was designed to enhance the rate of neuromuscular blockade monitoring for patients receiving muscle relaxant during anaesthesia. METHODS: After approval of our local ethical committee, we assessed 200 computerized anaesthesia records in which neuromuscular relaxants were used. The following data were collected: demographic characteristics, durations of anaesthesia and surgery, use of neuromuscular monitoring, reversal agents and the quality of neuromuscular monitoring. The results were discussed with all anaesthesia providers of the department and an internal guideline was elaborated with the endpoint that all patients having muscle relaxants should have quantitative neuromuscular monitoring. Six months later, another assessment of 200 consecutive records collected the same data to check the efficiency of the elaborated guideline. RESULTS: The monitoring rate was of 67% at the first assessment and increased to 94% (p<0.05). The reversal rate was at 48% in the first assessment and was stable at the second assessment (50%). The rate of patients not monitored and not reversed decreased from 5 to 2% (p<0.05). DISCUSSION: This study shows that as part of a quality assurance program systematic quantitative monitoring of neuromuscular blockade can be significantly increased.

Effect of pre-incisional continuous regional block on early and late postoperative conditions in tibial osteotomy and total knee arthroplasty.

BACKGROUND: Postoperative regional anesthesia hastens recovery and reduces the length of hospital stay of orthopedic surgical patients. This study was designed to assess the impact of pre-incisional continuous femoral block on postoperative conditions (POC) of tibial osteotomy and total knee arthroplasty patients. METHODS: After insertion of a femoral catheter under peripheral nerve stimulation control, 111 patients scheduled for total knee arthroplasty or tibial osteotomy were randomized to receive either pre-incisionnal (treatment) or postoperative (control) continuous femoral block. Anesthesia and postoperative management was standardized. An assessor blinded to the randomization process recorded early and late postoperative conditions (POC) which included pain scores, opioid demands, length of stay in Postoperative care unit and patients' satisfaction. RESULTS: Eleven patients were excluded from the final analysis because of catheter disconnection or malfunction. Thus 100 patients (50 in each group) were analyzed for POC. Treatment failed to influence patients overall satisfaction but significantly improved early POC. Subgroup analysis demonstrated that late POC were significantly improved in tibial osteotomy as compared to total knee arthroplasty patients. No complication occurred during the study period. CONCLUSION: Continuous femoral nerve block before surgery significantly improved early postoperative conditions in both surgery while late postoperative conditions were improved only in tibial osteotomy.

TOF count at corrugator supercilii reflects abdominal muscles relaxation better than at adductor pollicis.

BACKGROUND: A recovery profile from neuromuscular block similar to that of abdominal (AB) muscles, but different to that of the adductor pollicis (AP) muscle, has been demonstrated at the corrugator supercilii (CSC) muscle. We hypothesized that neuromuscular transmission (NMT) monitoring of CSC might provide useful information on AB relaxation compared with AP. We compared the visual estimation of NMT at CSC and AP with electromyographic measurements of AB during recovery from a vecuronium block. METHODS: Ten adult patients were studied during balanced anaesthesia. After induction of anaesthesia and tracheal intubation without neuromuscular blocking agents, supramaximal stimulations were applied to three nerves: left 10th intercostal, ulnar, and facial. Electromyographic activity (EMG) of AB was measured (ABemg). After a bolus dose of vecuronium 0.1 mg kg-1, an independent observer blinded to the EMG measurements counted visually detectable train-of-four (TOF) responses at CSC and AP. Values of ABemg associated with 1 to 4 TOF responses at CSC and AP were compared. Values are means (sd). RESULTS: Reappearance of the first and second TOF responses at CSC occurred significantly (P<0.05) earlier and at lower ABemg recovery than that of AP [35 (8) and 41 (9) min vs 51 (10) and 56 (12) min; and 17 (8) and 26 (9)% vs 56 (10) and 75 (11)%, respectively]. CONCLUSIONS: We demonstrated that the TOF response count at the CSC, compared with the AP, allowed a better quantification of the degree of AB muscle relaxation during recovery from vecuronium block.

Post-tetanic count at adductor pollicis is a better indicator of early diaphragmatic recovery than train-of-four count at corrugator supercilii.

BACKGROUND: Because the intensity of neuromuscular block at the diaphragm (DIA) is indirectly assessed, the electromyographic measurements of the DIA (DIA(EMG)) from surface electrodes were related to information provided by visual estimation of neuromuscular transmission at the adductor pollicis (AP) and the corrugator supercilii (CSC) during recovery from vecuronium block. METHODS: Twelve adult patients were studied during balanced anaesthesia. After induction of anaesthesia and tracheal intubation without neuromuscular blocking agent, supramaximal stimulations were applied to phrenic, ulnar and facial nerves. During recovery from vecuronium 0.1 mg kg(-1) an independent observer blinded to DIA(EMG) counted visually detectable train-of-four (TOF) at CSC (TOF(CSC)) and post-tetanic AP (PTC(AP)) responses. Times to recovery of PTC(AP) = 1, 10, and TOF(CSC) = 1-4 responses were related to DIA(EMG). Values are means (sd). RESULTS: Reappearance of the first response to PTC(AP) occurred significantly (P < 0.05) earlier and for a lower recovery of DIA(EMG) than that of TOF(CSC) [24 (8) min vs 33 (9) min, and 10 (10)% vs 25 (8)%, respectively]. With PTC(AP)

The effect of fentanyl and remifentanil, with or without ketoprofen, on pain after thyroid surgery: a randomized-controlled trial.

BACKGROUND AND OBJECTIVES: This study was designed to quantify the additional postoperative analgesic efficacy of a single dose of ketoprofen in patients undergoing thyroid surgery using two different intraoperative analgesic regimens. METHODS: One hundred and twenty patients were randomly assigned to one of four groups: intraoperative fentanyl or remifentanil with or without ketoprofen (n = 30 for each group). Intravenous ketoprofen (1.5 mg kg-1) or saline was administered 45 min before the end of surgery. Pain scores, opioid demand and length of stay in the postanaesthesia care unit were assessed in a blinded manner. RESULTS: Patients receiving intraoperative fentanyl with saline had significantly lower visual analogue scale pain scores in the postanaesthesia care unit compared with those receiving intraoperative remifentanil with saline (55 +/- 10 mm vs. 80 +/- 18 mm, P < 0.05) and they stayed shorter in the postanaesthesia care unit (86 +/- 24 min vs. 126 +/- 37 min). In conjunction with intraoperative fentanyl, ketoprofen significantly decreased postoperative pain scores (40 +/- 10 mm, P < 0.05 compared with fentanyl alone) and opioid demand (4 of 30 patients vs. 14 of 30 patients compared with fentanyl alone, P < 0.05). Patients receiving intraoperative remifentanil had no additional analgesic benefit with ketoprofen. CONCLUSION: After thyroid surgery, patients receiving intraoperative fentanyl had lower pain scores and needed less rescue analgesia compared with patients receiving intraoperative remifentanil. The adjunction of ketoprofen further improved analgesia in patients who received intraoperative fentanyl only.

Does repetition of post-tetanic count every 3 min during profound relaxation affect accelerographic recovery of atracurium blockade?

BACKGROUND: Post-tetanic count is a valuable method to assess profound neuromuscular blockade. However, subsequent responses to repetitive stimulation might be altered due to post tetanic facilitation (PTF). To avoid PTF, it has been advocated to limit the interval of stimulation from 6 to 10 min. The impact of PTF on 90% recovery of the TOF ratio has not been evaluated. Therefore, we assessed the effect of repetitive PTC stimulation on atracurium blockade with the primary outcome being the time to reach 90% TOF recovery in comparison to classical TOF stimulation. METHODS: After informed consent 20 patients ASA I-II, scheduled for peripheral surgery under general anaesthesia and requiring tracheal intubation were enrolled into the study. Anaesthesia was induced with fentanyl, propofol, and atracurium, 0.5 mg kg(-1). Neuromuscular characteristics were assessed at the adductor pollicis by a TOF Watch((R)) accelerometer (Organon, Teknika, Holland) on each arm. After onset of maximum neuromuscular blockade, repetitive PTC every 3 min on one arm and repetitive TOF stimulation every 15 s on the opposite arm was performed. The following parameters were recorded: onset of maximum blockade, mean time of PTC stimulation, the maximum number of responses to PTC, time of the first and second TOF responses, and recovery profile until 90% TOF ratio. RESULTS: Time to reach 90% TOF recovery was similar on both arms (48 +/- 9 min), with a difference of 16 +/- 38 s between the arms (P = 0.64). The first and second responses of the TOF on the PTC-stimulated arm appeared at 29 +/- 8 min and 33 +/- 7 min, respectively. On the other arm the responses appeared at 30 +/- 8 min and 35 +/- 8 min, respectively (P < 0.05). CONCLUSION: Repetitive PTC stimulation every 3 min hastened the first and second responses of the TOF stimulation but we could not detect a significant difference in the 90% recovery of TOF ratio during atracurium blockade.