A randomized controlled trial comparing three supraglottic airway devices used as a conduit to facilitate tracheal intubation with flexible bronchoscopy.

PURPOSE: Once difficult ventilation and intubation are declared, guidelines suggest the use of a supraglottic airway (SGA) as a rescue device to ventilate and, if oxygenation is restored, subsequently as an intubation conduit. Nevertheless, few trials have formally studied recent SGA devices in patients. Our objective was to compare the efficacy of three second-generation SGA devices as conduits for bronchoscopy-guided endotracheal intubation. METHODS: In this prospective, single-blinded three-arm randomized controlled trial, patients with an American Society of Anesthesiologists Physical Status of I-III undergoing general anesthesia were randomized to bronchoscopy-guided endotracheal intubation using AuraGain™, Air-Q® Blocker, or i-gel® devices. We excluded patients with contraindications to an SGA or drugs and who were pregnant or had a neck, spine, or respiratory anomaly. The primary outcome was intubation time, measured from SGA circuit disconnection to CO2 measurement. Secondary outcomes included ease, time, and success of SGA insertion; success of intubation on first attempt; overall intubation success; number of attempts to intubate; ease of intubation; and ease of SGA removals. RESULTS: One hundred and fifty patients were enrolled from March 2017 to January 2018. Median intubation times were similar across the three groups (Air-Q Blocker, 44 sec; AuraGain, 45 sec; i-gel, 36 sec; P = 0.08). The i-gel was faster to insert (i-gel: 10 sec; Air-Q Blocker, 16 sec; AuraGain, 16 sec; P < 0.001) and easier to insert (Air-Q Blocker vs i-gel, P = 0.001; AuraGain vs i-gel, P = 0.002). Success of SGA insertion, success of intubation, and number of attempts were similar. The Air-Q Blocker was easier to remove than the i-gel (P < 0.001). CONCLUSION: All three second-generation SGA devices performed similarly regarding intubation. Despite minor benefits of the i-gel, clinicians should select their SGA based on clinical experience. STUDY REGISTRATION: ClinicalTrials.gov (NCT02975466); registered on 29 November 2016.

RéSUMé: OBJECTIF: Une fois qu'une ventilation et une intubation difficiles sont déclarées, les lignes directrices préconisent le recours à un dispositif supraglottique comme modalité de sauvetage pour ventiler le patient et, si l'oxygénation est rétablie, être ensuite utilisé comme conduit d'intubation. Toutefois, peu d'études ont formellement analysé l'utilisation des dispositifs supraglottiques récents chez de véritbales patients. Notre objectif était de comparer l'efficacité de trois dispositifs supraglottiques de deuxième génération utilisés comme conduits pour l'intubation endotrachéale guidée par bronchoscopie. MéTHODE: Dans cette étude prospective randomisée contrôlée à trois bras et à simple insu, les patients de statut physique I-III selon l'American Society of Anesthesiologists bénéficiant d'une anesthésie générale ont été randomisés à recevoir une intubation endotrachéale guidée par bronchoscopie via les dispositifs AuraGain™, Air-Q® Blocker ou i-gel®. Nous avons exclu les patients présentant des contre-indications à l'utilisation d'un dispositif supraglottique ou aux médicaments, ainsi que les patientes enceintes et les patients présentant une anomalie au niveau du cou, de la colonne vertébrale ou des voies aériennes. Le critère d'évaluation principal était le temps d'intubation mesuré entre le moment de déconnexion du dispositif supraglottique du circuit et le moment de mesure du CO2. Les critères d'évaluation secondaires comprenaient la facilité, le délai et la réussite de l'insertion du dispositif supraglottique; la réussite de l'intubation à la première tentative; la réussite globale de l'intubation; le nombre de tentatives d'intubation; la facilité d'intubation; et la facilité de retrait du dispositif supraglottique. RéSULTATS: Cent cinquante patients ont été recrutés de mars 2017 à janvier 2018. Les délais d'intubation médians étaient similaires dans les trois groupes (Air-Q Blocker : 44 sec; AuraGain : 45 sec; i-gel : 36 sec; P = 0,08). L'i-gel était plus rapide à insérer (i-gel : 10 sec; Air-Q Blocker : 16 sec; AuraGain : 16 sec; P < 0,001) et plus facile à insérer (Air-Q Blocker vs i-gel : P = 0,001; AuraGain vs i-gel : P = 0,002). La réussite de l'insertion du dispositif supraglottique, la réussite de l'intubation et le nombre de tentatives étaient similaires. L'Air-Q Blocker était plus facile à retirer que l'i-gel (P < 0,001). CONCLUSION: Les trois dispositifs supraglottiques de deuxième génération ont tous affiché une performance similaire en matière d'intubation. Malgré des avantages mineurs de l'i-gel, les cliniciens devraient choisir leur dispositif supraglottique en fonction de leur expérience clinique. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT02975466); enregistrée le 29 novembre 2016.

Sex-Related Effects of Adrenergic Drugs on Conditioned Pain Modulation: A Randomized Controlled Cross-Over Double-Blind Trial.

Objective: Endogenous pain inhibition can be investigated using conditioned pain modulation (CPM). CPM efficacy has been reported to be influenced by various factors, such as gender and cardiovascular (autonomic) activity. The aim of this study is to describe the effect of pharmacological manipulations of autonomic activity on CPM efficacy. Methods: Thirty healthy participants were enrolled to assess CPM efficacy in 4 experimental sessions. The first session consisted of the determination of baseline CPM effectiveness. The three following sessions were performed in a randomized order and consisted of the injection of (1) esmolol, (2) ephedrine, or (3) placebo, before the conditioning stimulus. Pain intensity induced by using a contact heat stimulation thermode was compared before and after a cold-pressure conditioning stimulus to evaluate CPM effectiveness. Results: Our results show that inhibiting sympathetic nervous activity with esmolol did not have a significant effect on CPM. Conversely, enhancing sympathetic nervous activity with ephedrine increased CPM effectiveness in healthy women but decreased it in men. Conclusions: Increasing sympathetic activity with adrenergic agonists, such as ephedrine, could improve CPM effectiveness in women. It will be interesting to verify if the same results are present in patients suffering from chronic pain and if adrenergic agonists could have better therapeutic effects in women showing reduced CPM effectiveness.

Retroclavicular vs Infraclavicular block for brachial plexus anesthesia: a multi-centric randomized trial.

BACKGROUND: The coracoid approach is a simple method to perform ultrasound-guided brachial plexus regional anesthesia (RA) but its simplicity is counterbalanced by a difficult needle visualization. We hypothesized that the retroclavicular (RCB) approach is not longer to perform when compared to the coracoid (ICB) approach, and improves needle visualization. METHODS: This randomized, controlled, non-inferiority trial conducted in two hospitals, included patients undergoing distal upper limb surgery. Patients were randomly assigned to a brachial plexus block (ICB or RCB). The primary outcome was performance time (sum of visualization and needling time), and was analyzed with a non-inferiority test of averages. Depth of sensory and motor blockade, surgical success, total anesthesia time, needle visualization, number of needle passes and complications were also evaluated. Subgroup analysis restricted to patients with higher body mass index was completed. RESULTS: We included 109 patients between September 2016 and May 2017. Mean RCB performance time was 4.8 ± 2.0 min while ICB was 5.2 ± 2.3 min (p = 0.06) with a 95% CI reaching up to 5.8% longer. RCB conferred an ultrasound-needle angle closer to 0° and significantly improved needle visibility after the clavicle was cleared and before local anesthetic administration. No differences were found in the secondary outcomes. Similar results were found in the subgroup analysis. CONCLUSION: RCB approach for brachial plexus anesthesia was similar to ICB approach in terms of time performance. Needle visibility, which represent an important clinical variable, was superior and angle between needle and ultrasound probe was close to 0° in the RCB group. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT02913625), registered 26 September 2016.

Early Evidence of Sepsis-Associated Hyperperfusion-A Study of Cerebral Blood Flow Measured With MRI Arterial Spin Labeling in Critically Ill Septic Patients and Control Subjects.

OBJECTIVES: Mechanisms underlying sepsis-associated encephalopathy remain unclear, but reduced cerebral blood flow, alone or in conjunction with altered autoregulation, is reported as a potential contributor. We compared cerebral blood flow of control subjects and vasopressor-dependent septic patients. DESIGN: Randomized crossover study. SETTING: MRI with arterial spin labeling. PATIENTS: Ten sedated septic patients on mechanical ventilation (four with controlled chronic hypertension) and 12 control subjects (six with controlled chronic hypertension) were enrolled. Mean ± SD ages were 61.4 ± 10.2 and 44.2 ± 12.8 years, respectively (p = 0.003). Mean Acute Physiology and Chronic Health Evaluation II score of septic patients at ICU admission was 27.7 ± 6.6. INTERVENTIONS: To assess the potential confounding effects of sedation and mean arterial pressure, we measured cerebral blood flow with and without sedation with propofol in control subjects and at a target mean arterial pressure of 65 mm Hg and greater than or equal to 75 mm Hg in septic patients. The sequence of sedation versus no sedation and mean arterial pressure targets were randomized. MEASUREMENTS AND MAIN RESULTS: In septic patients, cerebral blood flow measured at a mean arterial pressure target of 65 mm Hg (40.4 ± 10.9 mL/100 g/min) was not different from cerebral blood flow measured at a mean arterial pressure target of greater than or equal to 75 mm Hg (41.3 ± 9.8 mL/100 g/min; p = 0.65). In control subjects, we observed no difference in cerebral blood flow measured without and with sedation (24.8 ± 4.2 vs 24.9 ± 5.9 mL/100 g/min; p = 0.93). We found no interaction between chronic hypertension and the effect of sedation or mean arterial pressure targets. Cerebral blood flow measured in sedated septic patients (mean arterial pressure target 65 mm Hg) was 62% higher than in sedated control subjects (p = 0.001). CONCLUSIONS: In septic patients, cerebral blood flow was higher than in sedated control subjects and did not vary with mean arterial pressure targets. Further research is required to understand the clinical significance of cerebral hyperperfusion in septic patients on vasopressors and to reassess the neurologic effects of current mean arterial pressure targets in sepsis.

Intracuff 160 mg alkalinized lidocaine reduces cough upon emergence from N2O-free general anesthesia: a randomized controlled trial.

PURPOSE: Chemical and mechanical irritation of the tracheal mucosa influences the incidence of cough at emergence from general anesthesia, potentially leading to significant postoperative complications. This study evaluates the benefits of endotracheal tube (ETT) intracuff alkalinized lidocaine during N2O-free general anesthesia by 1) assessing the in vitro effect of alkalinization on lidocaine diffusion kinetics across the cuff's membrane and 2) evaluating, in a randomized controlled clinical trial, the impact of 160 mg of intracuff alkalinized lidocaine on cough upon emergence from anesthesia for surgery lasting > 120 min. METHODS: In the in vitro study, diffusion kinetics of various intracuff alkalinized lidocaine amounts (40, 80, and 160 mg) were compared to their non-alkalinized lidocaine controls. In the clinical trial, 80 adult patients (American Society of Anesthesiologists physical status I-III) undergoing urological or gynecological surgery expected to last > 120 min and scheduled for N2O-free general anesthesia were enrolled. The ETT cuffs (high-volume, low-pressure) were filled with either 160 mg of alkalinized lidocaine or a comparable volume of 0.9% saline. The primary outcome was the incidence of cough upon emergence from anesthesia. Sore throat, hoarseness, and postoperative nausea and vomiting were evaluated as secondary outcomes. RESULTS: Our in vitro study confirmed that alkalinization increases lidocaine diffusion across the membrane of ETT cuffs and suggested that the lidocaine diffusion rate is associated with the initial intracuff lidocaine quantity. Our clinical trial demonstrated that, compared with the saline group, 160 mg of intracuff alkalinized lidocaine reduced the incidence of cough upon emergence from N2O-free general anesthesia (76% vs 34%, respectively; difference 42%; 95% confidence interval, 21% to 62%; P < 0.001) while having no clinical impact on secondary outcomes. CONCLUSIONS: The use of 160 mg of intracuff alkalinized lidocaine is associated with a decreased incidence of cough upon emergence from N2O-free general anesthesia > 120 min. This trial was registered at www.clinicaltrials.gov (NCT01774292).

The Ultrasound-Guided Retroclavicular Block: A Prospective Feasibility Study.

BACKGROUND AND OBJECTIVES: The aim of this feasibility study was to determine the success rate (sensory and surgical) of the novel retroclavicular block and to thoroughly describe the technique. In addition, needle tip and shaft visibility, needling time, procedural discomfort, motor block success rate, patient satisfaction at 48-hour follow-up, and complications were also recorded. METHODS: Fifty patients scheduled for distal upper limb surgery received an in-plane, single-shot, ultrasound-guided retroclavicular block with 40 mL of mepivacaine 1.5% with epinephrine 2.5 µg/mL. Block success was defined as a sensory score of 10/10 for the 5 nerves supplying the distal upper limb at 30 minutes. Surgical success, needle visibility, needling time, axillary artery depth, motor block rate, patient discomfort with technique, satisfaction at 48 hours, and complications were also recorded. All blocks were video-recorded and timed for further independent assessment. A chest x-ray was obtained before discharge. RESULTS: Forty-five patients had a total sensory score of 10/10 at 30 minutes (90% success rate). Surgical success rate was 96%. Mean needling time was 3.77 minutes (25th-75th percentiles, 2.90-6.53 minutes) with a mean axillary artery depth of 3.1 ± 0.7 cm. Procedure-related discomfort (mean visual analog scale, 1.9 ± 1.2) was low. Mean 48-hour patient satisfaction rate (9.2 ± 1.1), mean needle tip (Likert scale, 3.0 ± 0.9), and shaft visibility (3.9 ± 0.9) were high. One vascular puncture and two transient paresthesias were recorded. No pneumothorax was revealed by chest x-ray. CONCLUSIONS: In this study, the novel retroclavicular block offered a quick, safe, and reliable alternative for distal arm block. Further studies, comparing this approach with the classic infraclavicular block, are required to validate its efficacy, safety, and reliability.

Relationship between blood- and cerebrospinal fluid-bound neurotransmitter concentrations and conditioned pain modulation in pain-free and chronic pain subjects.

UNLABELLED: Descending pain inhibition is an endogenous pain control system thought to depend partially on the activation of bulbospinal monoaminergic pathways. Deficits in descending pain inhibition have been reported in numerous human chronic pain conditions, but there is currently no consensus regarding the neurochemical correlates responsible for this deficit. The aims of this study were to 1) assess the efficacy of descending pain inhibition in pain-free and chronic pain subjects, 2) screen for changes in centrally (ie, cerebrospinal fluid) and peripherally (ie, plasma) acting monoamine concentrations, and 3) explore the relationship between descending pain inhibition and monoamine neurotransmitter concentrations. Our results clearly show a deficit in pain inhibition, along with lower plasma norepinephrine and metanephrine concentrations in chronic pain subjects, compared to pain-free subjects. No differences were found in cerebrospinal fluid neurotransmitter concentrations. Finally, our results revealed a positive relationship between blood-bound norepinephrine and metanephrine concentrations and the efficacy of descending pain inhibition. Thus, basal monoamine levels in blood were related to descending pain inhibition. This finding supports the emerging idea that individual differences in descending pain inhibition may be linked to individual differences in peripheral processes, such as monoamines release in blood, which are possibly related to cardiovascular control. PERSPECTIVES: This article presents psychophysical and neurochemical findings that indicate that the latent potential of descending pain inhibitory responses is associated with differential activity in peripheral processes governed by monoamine neurotransmitter release, bringing insights into the relationship between descending pain inhibition and cardiovascular control in humans.

The effects of lidocaine spray and intracuff alkalinized lidocaine on the occurrence of cough at extubation: a double-blind randomized controlled trial.

PURPOSE: Our study aimed to evaluate the effects of lidocaine sprayed onto the larynx and/or injected into the tracheal tube cuff to decrease the incidence of cough at extubation and postoperative sore throat. METHODS: One hundred twenty women scheduled for gynecological surgery < 120 min in duration were enrolled in this randomized double-blind prospective study. Prior to tracheal intubation, 4% lidocaine or 0.9% saline was sprayed onto the patients' supra- and subglottic areas. After tracheal intubation, the tracheal tube cuff was filled with either an alkalinized 2% lidocaine solution or 0.9% saline. This resulted in four groups: spray-cuff, spray-saline, saline-cuff, and saline-saline. A logistic regression comprising the two factors was used for analysis. The primary outcome was the incidence of cough at extubation. The secondary outcome was the incidence and severity of sore throat reported by patients at 15 min, 60 min, and 24 hr after tracheal extubation. RESULTS: Cough occurred in 42%, 24%, 63%, and 69% of patients in the spray-cuff, spray-saline, saline-cuff, and saline-saline groups, respectively. The use of lidocaine spray decreased the incidence of cough at extubation (odds ratio = 0.256; 95% confidence interval 0.118 to 0.554; P < 0.001); however, the use of intracuff alkalinized lidocaine had no impact on the occurrence of cough (P = 0.471). Severity of sore throat was clinically low (visual analog scale [VAS] ≤ 3) in all groups. No significant difference was observed in hoarseness, dysphagia, nausea, or vomiting. CONCLUSION: Sprayed lidocaine decreases the incidence of cough at tracheal extubation in surgeries of less than two hours. The use of alkalinized lidocaine into high-volume/low-pressure endotracheal cuffs had no impact on decreasing the incidence of cough or pain.

Preoperative pregabalin does not reduce propofol ED(50): a randomized controlled trial.

BACKGROUND: In many studies, gabapentinoids, such as pregabalin, have been shown to reduce preoperative anxiety. This anxiolysis is often accompanied by sedation, one of the most frequent side effects of pregabalin. We hypothesized that pregabalin taken preoperatively could reduce propofol requirements for induction of general anesthesia. METHODS: A randomized double-blind placebo-controlled trial was conducted after approval by the local ethics committee. Fifty women aged 18-40 yr, American Anesthesiologists Society physical status I and II, and scheduled to undergo elective laparoscopic gynecologic procedures were enrolled after written consent. Treatment group patients were given pregabalin 150 mg po one hour before surgery while patients in the control group received a placebo. The primary outcome was the propofol dose required to achieve a targeted anesthetic depth in 50% of the population, i.e., effective dose (ED)50. The ED50 was estimated using Dixon's up-and-down methodology. The targeted anesthetic depth was defined based on predetermined entropy monitoring values (State Entropy [SE] < 50 and Response Entropy [RE]-SE < 10). As a secondary outcome, we tested if pregabalin reduced pre-induction anxiety levels which were measured on a 0-100 scale. RESULTS: The propofol ED50 was not statistically different between the pregabalin group (mean 1.33 mg·kg(-1); 95% confidence interval [CI] 1.23 to 1.43) vs the placebo group (mean 1.37 mg·kg(-1); 95% CI 1.28 to 1.46); P = 0.19. Also, pre-induction anxiety level was not different between groups (median 31; interquartile range [IQR] [10-52] vs median 42; IQR [4-71], respectively; P = 0.41). CONCLUSIONS: Preoperative pregabalin does not reduce propofol requirements in a population of healthy young women undergoing laparoscopic gynecologic procedures. This study failed to show a pre-induction anxiolytic effect of pregabalin in such a population. This trial was registered at www.clinicaltrials.gov (NCT01158859).