Efficacy of a propofol bolus against placebo to prevent cough at emergence from general anesthesia with desflurane: a randomized controlled trial.

PURPOSE: Emergence from anesthesia is a critical period and cough can result in adverse effects. Propofol inhibits airway reflexes and when infused it reduces cough more than inhalation anesthesia does. We evaluated the effect of a propofol bolus given at emergence on the incidence of coughing following a desflurane-based anesthesia. METHODS: One hundred and fifty-four patients scheduled for elective surgery were prospectively randomized to propofol (0.5 mg·kg-1) or normal saline (NS) administered at the end of the surgery at 1 minimum alveolar concentration (MAC) of desflurane. A "no touch" emergence technique was used until extubation. The primary outcome was the incidence of cough at the discontinuation of desflurane (T0) and reaching a MAC adjusted for age (MACage) of 0.15. Secondary outcomes included incidence and severity of cough until five minutes postextubation (T0-T5), time to extubation, nausea and vomiting, sedation, hemodynamic variations, postoperative hypoventilation, hypoxemia, and sore throat. RESULTS: We could not draw inferences on the incidence of cough between T0 and MACage of 0.15 because only 27/68 (40%) patients in the NS group and 13/73 (18%) patients in the propofol group regained consciousness before reaching a MACage of 0.15. There were no significant differences between the groups in coughing incidence and severity between T0 and T5 (NS group, 57/68 [84%] vs propofol group, 70/73 [96%] ). The mean time to extubation in the propofol group was prolonged by 3 min 27 sec (95% confidence interval, 1 min 7 sec to 4 min 47 sec; P < 0.001) and more vasopressors were used at emergence (P = 0.02). The incidence of respiratory complications, nausea and vomiting, agitation, and sedation were not different between groups. CONCLUSION: In the present trial, a propofol bolus administered at emergence did not reduce the incidence of cough occurring between T0 and T5 following a desflurane-based general anesthesia compared with placebo. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02932397); registered 13 October 2016.

RéSUMé: OBJECTIF: L'émergence de l'anesthésie est une période critique et la toux peut entraîner des effets indésirables. Le propofol inhibe les réflexes des voies aériennes et, lorsqu'il est perfusé, il est plus efficace pour réduire la toux que l'anesthésie inhalée. Nous avons évalué l'effet d'un bolus de propofol administré à l'émergence sur l'incidence de toux après une anesthésie à base de desflurane. MéTHODE: Cent cinquante-quatre patients devant bénéficier d'une chirurgie non urgente ont été randomisés prospectivement à recevoir du propofol (0,5 mg·kg−1) ou une solution physiologique de sérum salé (NS) administrée à la fin de la chirurgie lorsque la concentration alvéolaire minimale (MAC) de desflurane était de 1. Une technique d'émergence « sans contact ¼ a été utilisée jusqu'à l'extubation. Le critère d'évaluation principal était l'incidence de toux à l'arrêt du desflurane (T0) et à l'atteinte d'une MAC ajustée en fonction de l'âge (MACâge) de 0,15. Les critères d'évaluation secondaires comprenaient l'incidence et la gravité de la toux jusqu'à cinq minutes après l'extubation (T0-T5), le délai d'extubation, les nausées et vomissements, la sédation, les variations hémodynamiques, l'hypoventilation postopératoire, l'hypoxémie et les maux de gorge. RéSULTATS: Nous n'avons pas pu tirer de conclusions sur l'incidence de toux entre T0 et à une MACâge de 0,15 parce que seulement 27/68 (40 %) patients du groupe NS et 13/73 (18 %) patients du groupe propofol ont repris conscience avant d'atteindre une MACâge de 0,15. Il n'y avait aucune différence significative entre les groupes dans l'incidence et la gravité de la toux entre T0 et T5 (groupe NS, 57/68 [84 %] vs groupe propofol, 70/73 [96 %]). Le temps moyen d'extubation dans le groupe propofol a été prolongé de 3 min 27 sec (intervalle de confiance à 95 %, 1 min 7 sec à 4 min 47 sec; P < 0,001) et une plus grande quantité de vasopresseurs a été utilisée à l'émergence (P = 0,02). L'incidence de complications respiratoires, de nausées et vomissements, d'agitation, et de sédation n'était pas différente entre les groupes. CONCLUSION: Dans la présente étude, un bolus de propofol administré à l'émergence n'a pas réduit l'incidence de toux survenant entre T0 et T5 après une anesthésie générale à base de desflurane par rapport au placebo. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT02932397); enregistrée le 13 octobre 2016.

Phlebotomy resulting in controlled hypovolemia to prevent blood loss in major hepatic resections (PRICE-2): study protocol for a phase 3 randomized controlled trial.

INTRODUCTION: Blood loss and red blood cell (RBC) transfusion in liver surgery are areas of concern for surgeons, anesthesiologists, and patients alike. While various methods are employed to reduce surgical blood loss, the evidence base surrounding each intervention is limited. Hypovolemic phlebotomy, the removal of whole blood from the patient without volume replacement during liver transection, has been strongly associated with decreased bleeding and RBC transfusion in observational studies. This trial aims to investigate whether hypovolemic phlebotomy is superior to usual care in reducing RBC transfusions in liver resection. METHODS: This study is a double-blind multicenter randomized controlled trial. Adult patients undergoing major hepatic resections for any indication will be randomly allocated in a 1:1 ratio to either hypovolemic phlebotomy and usual care or usual care alone. Exclusion criteria will be minor resections, preoperative hemoglobin <100g/L, renal insufficiency, and other contraindication to hypovolemic phlebotomy. The primary outcome will be the proportion of patients receiving at least one allogeneic RBC transfusion unit within 30 days of the onset of surgery. Secondary outcomes will include transfusion of other allogeneic blood products, blood loss, morbidity, mortality, and intraoperative physiologic parameters. The surgical team will be blinded to the intervention. Randomization will occur on the morning of surgery. The sample size will comprise 440 patients. Enrolment will occur at four Canadian academic liver surgery centers over a 4-year period. Ethics approval will be obtained at participating sites before enrolment. DISCUSSION: The results of this randomized control trial will provide high-quality evidence regarding the use of hypovolemic phlebotomy in major liver resection and its effects on RBC transfusion. If proven to be effective, this intervention could become standard of care in liver operations internationally and become incorporated within perioperative patient blood management programs. TRIAL REGISTRATION: ClinicalTrials.gov NCT03651154 . Registered on August 29 2018.

Peak plasma concentration of total and free bupivacaine after erector spinae plane and pectointercostal fascial plane blocks.

PURPOSE: Erector spinae plane blocks (ESPB) and pectointercostal fascial (PIFB) plane blocks are novel interfascial blocks for which local anesthetic (LA) doses and concentrations necessary to achieve safe and effective analgesia are unknown. The goal of this prospective observational study was to provide the timing (Tmax) and concentration (Cmax) of maximum total and free plasma bupivacaine after ESPB in breast surgery and after PIFB in cardiac surgery patients. METHODS: Erector spinae plane blocks or PIFBs (18 patients per block; total, 36 patients) were performed with 2 mg⋅kg-1 of bupivacaine with epinephrine 5 µg⋅mL-1. Our principal outcomes were the mean or median Cmax of total and free plasma bupivacaine measured 10, 20, 30, 45, 60, 90, 180, and 240 min after LA injection using liquid chromatography with tandem mass spectrometry. RESULTS: For ESPB, the mean (standard deviation [SD]) total bupivacaine Cmax was 0.37 (0.12) µg⋅mL-1 (range, 0.19 to 0.64), and the median [interquartile range (IQR)] Tmax was 30 [50] min (range, 10-180). For ESPB, the mean (SD) free bupivacaine Cmax was 0.015 (0.017) µg⋅mL-1 (range, 0.003-0.067), and the median [IQR] Tmax was 30 [20] min (range, 10-120). After PIFB, mean plasma concentrations plateaued at 60-240 min. For PIFB, the mean (SD) total bupivacaine Cmax was 0.32 (0.21) µg⋅mL-1 (range, 0.14-0.95), with a median [IQR] Tmax of 120 [150] min (range, 30-240). For PIFB, the mean (SD) free bupivacaine Cmax was 0.019 (0.010) µg⋅mL-1 (range, 0.005-0.048), and the median [IQR] Tmax was 180 [120] min (range, 30-240). For both ESPB and PIFB, we observed no correlations between pharmacokinetic and demographic parameters. CONCLUSION: Total and free bupivacaine Cmax observed after ESPB and PIFB with 2 mg⋅kg-1 of bupivacaine with epinephrine 5 µg⋅mL-1 were five to twenty times lower than levels considered toxic in the literature.

RéSUMé: OBJECTIF: Les blocs des muscles érecteurs du rachis (ESP) et les blocs des plans fasciaux pecto-intercostaux (PIFB) sont de nouveaux blocs interfasciaux pour lesquels les doses et les concentrations d'anesthésique local (AL) nécessaires à obtenir une analgésie sécuritaire et efficace sont inconnues. L'objectif de cette étude observationnelle prospective était de déterminer le moment d'administration (Tmax) et la concentration (Cmax) de bupivacaïne plasmatique totale et plasmatique libre maximale après un bloc ESP pour chirurgie mammaire et après un PIFB chez les patients en chirurgie cardiaque. MéTHODE: Des blocs ESP ou PIFB (18 patients par bloc; total, 36 patients) ont été réalisés avec 2 mg⋅kg-1 de bupivacaïne et 5 µg⋅mL-1 d'épinéphrine. Nos principaux critères d'évaluation étaient la Cmax moyenne ou médiane de bupivacaïne plasmatique totale et libre mesurée 10, 20, 30, 45, 60, 90, 180 et 240 min après l'injection d'AL par chromatographie liquide avec spectrométrie de masse en tandem. RéSULTATS: Pour le bloc ESP, la Cmax de bupivacaïne totale moyenne (écart type [ET]) était de 0,37 (0,12) µg⋅mL-1 (plage, 0,19 à 0,64), et le Tmax médian [écart interquartile (ÉIQ)] était de 30 [50] min (intervalle, 10­180). Pour le bloc ESP, la Cmax de bupivacaïne libre moyenne (ET) était de 0,015 (0,017) µg⋅mL-1 (plage, 0,003­0,067), et le Tmax médian [ÉIQ] était de 30 [20] min (intervalle, 10­120). Après un PIFB, les concentrations plasmatiques moyennes ont plafonné à 60­240 min. Pour le bloc PIFB, la Cmax de bupivacaïne totale moyenne (ET) était de 0,32 (0,21) µg⋅mL-1 (plage, 0,14­0,95), et le Tmax médian [ÉIQ] était de 120 [150] min (intervalle, 30­240). Pour le bloc PIFB, la Cmax de bupivacaïne libre moyenne (ET) était de 0,019 (0,010) µg⋅mL-1 (plage, 0,005­0,048), et le Tmax médian [ÉIQ] était de 180 [120] min (intervalle, 30­240). Pour le bloc ESP et le PIFB, nous n'avons observé aucune corrélation entre les paramètres pharmacocinétiques et démographiques. CONCLUSION:  : Les Cmax de bupivacaïne totale et libre observées après un bloc ESP et PIFB avec 2 mg⋅kg-1 de bupivacaïne avec 5 µg⋅mL-1 d'épinéphrine étaient cinq à vingt fois plus faibles que les niveaux considérés comme toxiques dans la littérature.

The impact of a perceptual learning module on novices' ability to visually estimate left ventricular ejection fraction by transesophageal echocardiography: a randomized controlled study.

PURPOSE: Echocardiography is a difficult tool to master. Competency requires the supervised interpretation of hundreds of exams. Perceptual learning modules (PLMs) are novel learning tools that aim to speed up this learning process by enabling learners to go online and interpret numerous clinical images, followed systematically by expert feedback. We developed and tested a PLM aimed at improving novices' ability to quickly visually estimate left ventricular ejection fraction (LVEF) on transesophageal echocardiography images, a critical skill in acute care. We hypothesized that using the PLM would improve the accuracy and the speed of learners' estimations. METHODS: Learners without echocardiography experience were randomly assigned to a group that used the 96-case PLM (n = 26) or a control group (n = 26) that did not. Both groups took a pre-test and an immediate post-test that measured the accuracy of their visual estimations during a first session. At six months, participants also completed a delayed post-test. RESULTS: In the immediate post-test, the PLM group showed significantly better accuracy than the control group (median absolute estimation error 6.1 vs 9.0; difference 95% CI, 1.0 to 4.6; P < 0.001). Nevertheless, at six months, estimation errors were similar in both groups (median absolute estimation error 10.0 vs 10.0; difference 95% CI, -1.3 to 2.1; P = 0.27). CONCLUSIONS: Participation in a short online PLM significantly improved novices' short-term ability to accurately estimate LVEF visually, compared with controls. The effect was not sustained at six months. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT03245567); registered 7 August 2017.

RéSUMé: OBJECTIF: L'échocardiographie est un outil difficile à maîtriser. Afin d'acquérir cette compétence, l'interprétation supervisée de centaines d'examens est nécessaire. Les modules d'apprentissage perceptuel (MAP) sont des outils d'apprentissage innovants qui visent à accélérer ce processus d'apprentissage en permettant aux apprenants d'aller en ligne et d'interpréter de nombreuses images cliniques, lesquelles sont systématiquement suivies par des rétroactions d'experts. Nous avons mis au point et testé un MAP visant à améliorer la capacité des nouveaux apprenants à rapidement estimer visuellement la fraction d'éjection ventriculaire gauche (FEVG) sur des images d'échocardiographie transœsophagienne, une compétence critique dans les soins aigus. Nous avons émis l'hypothèse que l'utilisation du MAP améliorerait la précision et la rapidité des estimations des apprenants. MéTHODE: Les apprenants sans expérience de lecture d'échocardiographie ont été aléatoirement alloués à un groupe qui a utilisé le MAP de 96 cas (n = 26) ou à un groupe témoin (n = 26) qui ne l'a pas utilisé. Les deux groupes ont passé un prétest et un post-test immédiat qui ont mesuré l'exactitude de leurs estimations visuelles au cours d'une première séance. Six mois plus tard, les participants ont également passé un autre post-test retardé. RéSULTATS: Dans le post-test immédiat, le groupe MAP a démontré une précision significativement meilleure que le groupe témoin (erreur d'estimation absolue médiane, 6,1 vs 9,0; différence de l'IC 95 %, 1,0 à 4,6; P < 0,001). Néanmoins, à six mois, les erreurs d'estimation étaient similaires dans les deux groupes (erreur d'estimation absolue médiane, 10,0 vs 10,0; différence de l'IC 95 %, -1,3 à 2,1; P = 0,27). CONCLUSION: La participation à un bref MAP en ligne a considérablement amélioré la capacité à court terme des nouveaux apprenants à estimer visuellement et avec précision la FEVG, par rapport à un groupe témoin. L'effet n'était pas maintenu à six mois. ENREGISTREMENT DE L'éTUDE: www.clinicaltrials.gov (NCT03245567); enregistrée le 7 août 2017.

Patient factors associated with difficult flexible bronchoscopic intubation under general anesthesia: a prospective observational study.

PURPOSE: Patient characteristics associated with difficult tracheal intubation using a flexible bronchoscope (FB) under general anesthesia have not been prospectively evaluated. This observational study aimed to identify demographic and morphologic factors associated with difficult FB intubation. METHODS: We recruited 420 adult elective surgery patients undergoing tracheal intubation during general anesthesia. Patients characteristics were recorded including age, sex, weight, height, body mass index, American Society of Anesthesiologists physical status, history of snoring, obstructive sleep apnea, Mallampati score, upper lip bite test score, neck circumference and skinfold thickness, maximal neck flexion and extension angles, absence of teeth, Cormack and Lehane grade, presence of blood or secretions during intubation, as well as the inter-incisor, thyromental, sternothyroid, and manubriomental distances. The time (duration) needed to complete intubation (primary endpoint) and the number of attempts needed were correlated with these patient characteristics in a multivariable analysis. RESULTS: Intubation was successful on the first attempt in 409/420 patients (97%). Seven patients (1.7%) needed more than one attempt. Failure to intubate with the FB occurred in four patients (1%). A correlation was found between intubation duration and visibility impaired by secretions or blood (P < 0.001), higher neck skinfold thickness (P < 0.001), and larger endotracheal tube diameter (relative to a constant 5.5 mm FB; P < 0.001). CONCLUSIONS: The presence of secretions or blood that impair FB glottic visualization, a larger diameter endotracheal tube on the same size FB, as well as higher neck skinfold thickness may prolong the duration of FB intubation under general anesthesia. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT02769819); registered 5 May, 2016.

RéSUMé: OBJECTIF: Les caractéristiques des patients associées à une intubation trachéale difficile avec un bronchoscope flexible sous anesthésie générale n'ont pas été évaluées de façon prospective. Cette étude observationnelle avait pour but d'identifier les facteurs démographiques et morphologiques associés aux intubations difficiles avec un bronchoscope flexible. MéTHODES: Nous avons recruté 420 patients adultes devant subir une intubation trachéale au cours d'une anesthésie générale pour une chirurgie élective. Les caractéristiques suivantes des patients ont été consignées : âge, sexe, poids, taille, indice de masse corporelle, score de l'American Society of Anesthesiologists, antécédents de ronflements et de syndrome d'apnée-hypopnée du sommeil, score de Mallampati, score du test de morsure de la lèvre supérieure, circonférence du cou et épaisseur du pli cutané cervical, angles maximums de flexion et extension du cou, absence de dents, grade de la classification de Cormack et Lehane, présence de sang ou de sécrétions pendant l'intubation, ainsi que les distances inter-incisives, menton-cartilage thyroïde, sterno-thyroïdienne et menton-manubrium. Le temps nécessaire pour compléter l'intubation (critère d'évaluation principal) et le nombre de tentatives nécessaires ont été corrélés aux caractéristiques des patients dans une analyse multifactorielle. RéSULTATS: L'intubation a été réussie dès la première tentative chez 409 patients sur 420 (97 %). Pour 7 patients (1,7 %, il a fallu plus d'une tentative. Un échec de l'intubation avec bronchoscope flexible est survenu chez 4 patients (1 %). Une corrélation a été trouvée entre la durée de l'intubation et une mauvaise visualisation due à des sécrétions ou du sang (P < 0,001), un pli cutané cervical plus épais (P < 0,001), et un plus grand diamètre du tube endotrachéal (par rapport à un fibroscope souple constant de 5,5 mm; P < 0,001). CONCLUSIONS: La présence de sang ou de sécrétions gênant la visualisation de la glotte, un diamètre du tube endotrachéal augmenté par rapport à celui du fibroscope flexible ainsi qu'une plus grande épaisseur du pli cutané cervical peuvent prolonger le temps d'intubation avec endoscope flexible sous anesthésie générale. ENREGISTREMENT DE L'ESSAI CLINIQUE: www.clinicaltrials.gov (NCT02769819); enregistré le 5 mai 2016.

Effect of Intravenous Dexamethasone on the Regression of Isobaric Bupivacaine Spinal Anesthesia: A Randomized Controlled Trial.

The effect of intravenous dexamethasone on the regression of sensory and motor block after isobaric bupivacaine spinal anesthesia is unknown. We conducted a prospective, double-blind, randomized controlled trial on 60 patients who received intravenously either placebo (group P) or 8-mg dexamethasone (group D) during the intrathecal injection of 12-mg isobaric bupivacaine 0.5%. Primary outcome was the time from bupivacaine injection to regression of 2 dermatomes in relation to the highest dermatome blocked by the spinal local anesthetic. Time to 2-dermatome regression was 85 minutes (74-96 minutes) in group P versus 87 minutes (76-98 minutes) in group D (P = .79).

Anticoagulation Obtained below the Arterial Clamp Using a Single Fixed Bolus of Heparin in Vascular Surgery: A Pilot Study.

BACKGROUND: No clear recommendations exist regarding the optimal dosing of unfractionated heparin (UFH) during vascular surgery. Moreover, little is known about the effect of the UFH bolus downstream of the arterial clamp, where stasis and inflammation can possibly alter the anticoagulation obtained. METHODS: The aim of our prospective observational study was to assess anticoagulation below the arterial clamp and its clinical impact on the quality of revascularization. Thirty-six patients American Society of Anaesthesiologists physical status (ASA) grade I-III undergoing open revascularization surgeries were included. A baseline activated coagulation time (ACT) was obtained. Thirty minutes after a single bolus of 5,000 units of UFH, we measured an upstream ACT via a radial arterial catheter and an ACT below the arterial clamp via surgeon sampling. The quality of revascularization was assessed with preoperative and postoperative ankle-brachial and toe-brachial indexes (TBIs). RESULTS: The upstream postheparin ACT was significantly higher than the downstream postheparin ACT, with a mean difference of 24.3 sec (P < 0.0001). In 7 patients, the downstream ACT was lower than the baseline ACT. The upstream and downstream heparin concentrations were similar. There was no relationship between the downstream ACT and either ankle-brachial index improvement (28 patients, P = 0.51) or TBI improvement (27 patients, P = 0.21). CONCLUSIONS: Our study demonstrates a significant difference between the ACT above and below the arterial clamp without any clinical impact of this possibly insufficient anticoagulation. Further investigations are warranted to determine the optimal dose of UFH in vascular surgery. TRIAL REGISTRATION: Clinicaltrials.gov, NCT02477072.

The Effect of Adductor Canal Block on Knee Extensor Muscle Strength 6 Weeks After Total Knee Arthroplasty: A Randomized, Controlled Trial.

BACKGROUND: Total knee arthroplasty (TKA) reduces knee extensor muscle strength (KES) in the operated limb for several months after the surgery. Immediately after TKA, compared to either inguinal femoral nerve block or placebo, adductor canal block (ACB) better preserves KES. Whether this short-term increase in KES is maintained several weeks after surgery remains unknown. We hypothesized that 48 hours of continuous ACB immediately after TKA would improve KES 6 weeks after TKA, compared to placebo. METHODS: Patients scheduled for primary unilateral TKA were randomized to receive either a continuous ACB (group ACB) or a sham block (group SHAM) for 48 hours after surgery. Primary outcome was the difference in maximal KES 6 weeks postoperatively, measured with a dynamometer during maximum voluntary isometric contraction. Secondary outcomes included postoperative day 1 (POD1) and day 2 (POD2) KES, pain scores at rest and peak effort, and opioid consumption; variation at 6 weeks of Knee Osteoarthritis Outcome Score, patient satisfaction, and length of hospital stay. RESULTS: Sixty-three subjects were randomized and 58 completed the study. Patients in group ACB had less pain at rest during POD1 and during peak effort on POD1 and POD2, consumed less opioids on POD1 and POD2, and had higher median KES on POD1. There was no significant difference between groups for median KES on POD2, variation of Knee Osteoarthritis Outcome Score, patient satisfaction, and length of stay. There was no difference between groups in median KES 6 weeks after surgery (52 Nm [31-89 Nm] for group ACB vs 47 Nm [30-78 Nm] for group SHAM, P= .147). CONCLUSIONS: Continuous ACB provides better analgesia and KES for 24-48 hours after surgery, but does not affect KES 6 weeks after TKA. Further research could evaluate whether standardized and optimized rehabilitation over the long term would allow early KES improvements with ACB to be maintained over a period of weeks or months.

Alkalinized Lidocaine Preloaded Endotracheal Tube Cuffs Reduce Emergence Cough After Brief Surgery: A Prospective Randomized Trial.

BACKGROUND: Alkalinized lidocaine in the endotracheal tube (ETT) cuff decreases the incidence of cough and throat pain on emergence after surgery lasting more than 2 hours. However, alkalinized lidocaine needs 60-120 minutes to cross the ETT cuff membrane; therefore, its usefulness in shorter duration surgery is unknown. This prospective double-blind randomized controlled trial tested the hypothesis that alkalinized lidocaine would reduce the incidence of emergence cough after surgeries lasting <120 minutes. METHODS: After local ethics board approval, American Society of Anesthesiologists I-III patients consented to be randomized into 1 of 2 groups receiving either alkalinized lidocaine (group AL) or saline (group S) to inflate the ETT cuff. Cuffs were prefilled >90 minutes before intubation with either 2 mL of 2% lidocaine and 8 mL of 8.4% bicarbonate (group AL) or 10 mL of normal saline (group S). Cuffs were emptied immediately before intubation. After intubation, either 2 mL of 2% lidocaine (AL) or 2 mL of saline (S) were injected into the cuff. Additional 8.4% bicarbonate (AL) or saline (S) was injected into the cuff until there was no air leak. Anesthesia was maintained using desflurane, rocuronium, and either fentanyl or sufentanil to maintain vital signs within 20% of baseline values. Opioids administered in prophylaxis of extubation cough were proscribed. A standardized "no touch" emergence technique was used. A blinded assessor noted any cough above 0.2 minimum alveolar concentration (MAC) of expired desflurane. At 0.2 MAC, once every 30 seconds, the patient was instructed to open his eyes and extubation occurred once a directed response was noted. RESULTS: A total of 213 patients were randomized and 100 patients in each group completed the experimental protocol. The incidence of extubation cough in group AL was 12%, significantly lower (1-sided P = .045) than the 22% incidence in group S. The 1-tailed risk ratio for cough in group AL was 0.55 (0-0.94, P = .045). Total amount of opioids administered (P = .194), ETT cuff preloading times (P = .259), and extubation times (P = .331) were not significantly different between groups. The average duration of surgery was 59 ± 28 minutes in group AL and 52 ± 29 minutes in group S (P = .057). CONCLUSIONS: Alkalinized lidocaine in the ETT cuff significantly decreased general anesthesia emergence cough after surgeries with an average duration of slightly <1 hour.

Predictors of Difficult Intubation with the Bonfils Rigid Fiberscope.

BACKGROUND: Endotracheal intubation is commonly performed via direct laryngoscopy (DL). However, in certain patients, DL may be difficult or impossible. The Bonfils Rigid Fiberscope® (BRF) is an alternative intubation device, the design of which raises the question of whether factors that predict difficult DL also predict difficult BRF. We undertook this study to determine which demographic, morphologic, and morphometric factors predict difficult intubation with the BRF. METHODS: Four hundred adult patients scheduled for elective surgery were recruited. Patients were excluded if awake intubation, rapid sequence induction, or induction without neuromuscular blocking agents was planned. Data were recorded, including age, sex, weight, height, American Society of Anesthesiologist classification, history of snoring and sleep apnea, Mallampati class, upper lip bite test score, interincisor, thyromental and sternothyroid distances, manubriomental distances in flexion and extension, neck circumference, maximal neck flexion and extension, neck skinfold thickness at the cricoid cartilage, and Cormack and Lehane grade obtained via DL after paralysis was confirmed. Quality of glottic visualization (good or poor), as well as the number of intubation attempts and time to successful intubation with the BRF, was noted. Univariate analyses were performed to evaluate the association between patient characteristics and time required for intubation. Variables that exhibited a significant correlation were included in a multivariate analysis using a standard least squares model. A P < 0.05 was considered significant. RESULTS: Glottic visualization with the BRF was good in 396 of 400 (99%) cases. On the first attempt, 390 patients were successfully intubated with the BRF; 6 patients required >1 attempt; 4 patients could not be intubated by using the BRF alone. These 4 patients were intubated by using a combination of DL and BRF (2 patients), DL and a Frova bougie (1 patient), and DL and an endotracheal tube shaped with a semirigid stylet (1 patient). Mean time for successful intubation was 26 ± 13 seconds. Multivariate analysis showed that decreased mouth opening (P = 0.008), increased body mass index (P = 0.011), and higher Cormack and Lehane grade (P = 0.038) predicted longer intubation times, whereas shorter thyromental distance predicted slightly shorter intubation times (P < 0.0001). CONCLUSIONS: Mouth opening, body mass index, and high Cormack and Lehane grade predict longer intubation times, as with DL. Decreasing thyromental distance predicts slightly shorter intubation times with the BRF, possibly because of a design initially optimized for a pediatric population with receding chins. These findings, along with the high success rate of BRF in this study, and the possibility of further increasing success rates by combining BRF with DL, help define the role of BRF intubation in contemporary airway management.

Impact of thoracic epidural catheter threading distance on analgesia during the first 24 hours following thoracotomy: a randomized controlled trial.

PURPOSE: The purpose of this prospective randomized controlled trial was to determine the impact of thoracic epidural catheter threading distance on analgesia quality after thoracotomy. METHODS: We randomly assigned 120 elective thoracotomy patients to a thoracic epidural catheter threading distance of 3, 5, or 7 cm (groups 3CM, 5CM, and 7CM, respectively). Epidural bupivacaine 0.1% with fentanyl 2 µg·mL(-1) was administered according to a standardized protocol. Epidural analgesia quality was assessed at 60 min and 24 hr postoperatively for four measures: incidence of non-functioning epidurals; numerical rating score (NRS) < 4 at rest, while coughing, and during wound palpation; cold perception at the wound site; and cumulative dose of analgesic medication used. Our primary hypothesis was that, compared to threading distances of 3 and 5 cm, a threading distance of 7 cm was not inferior at providing an NRS < 4 while coughing at 60 min postoperatively, with a non-inferiority margin of 25% (absolute value) being significant. RESULTS: The incidence of NRS < 4 while coughing at 60 min was 74% (29/39) in group 7CM compared with 68% (54/80) in the combined 3CM and 5CM groups (absolute difference 7%; 95% confidence interval -11 to 23; P = 0.29). At both 60 min and 24 hr, differences between groups were similar regarding the number of non-functioning epidurals, NRS < 4, and suppressed cold sensation. Analgesic doses were similar in the three groups. CONCLUSIONS: This study found that a thoracic epidural catheter threading distance of 7 cm in the epidural space was not inferior to distances of 3 cm and 5 cm with respect to pain scores at 60 min postoperatively. This study was not powered to examine differences that could have clinical significance that were less than our a priori 25% non-inferiority margin.

I-gel Versus LMA-Fastrach Supraglottic Airway for Flexible Bronchoscope-Guided Tracheal Intubation Using a Parker (GlideRite) Endotracheal Tube: A Randomized Controlled Trial.

BACKGROUND: The I-gel (IG) supraglottic airway device is a reliable way to establish an airway. Its large ventilation lumen allows for easy passage of an endotracheal tube. With the use of a flexible bronchoscope, the IG offers a good visualization of the laryngeal inlet. This prospective randomized study aims to compare the success rate of flexible bronchoscope-guided tracheal intubation using either the IG or the LMA-Fastrach (FT) laryngeal masks. METHODS: One hundred twenty patients requiring general anesthesia were randomized to 1 of the 2 study groups: IG or FT. After anesthesia induction, the assigned laryngeal mask was inserted to obtain adequate ventilation. We then proceeded to a flexible bronchoscope-guided intubation through the supraglottic device. Tracheal intubation and laryngeal mask insertion success rates were noted, as well as the time required for these manipulations. The view of the laryngeal inlet was graded for each intubation attempt. RESULTS: Sixty patients were assigned to each study group. The intubation success rates were similar between the IG and the FT groups (100 % vs 95.0 % at first attempt; P = 0.12). The times required for tracheal intubation were significantly lower in the IG group (30 ± 11 seconds vs 50 ± 21 seconds; P < 0.0001). Glottic visualization was better in the IG group, with a significantly higher percentage of grade 1 visualization (63.3% vs 3.3%; P < 0.0001) and a lower percentage of grade 3 visualization (1.7% vs 60.0%; P < 0.0001), than that in the FT group. CONCLUSIONS: The use of the IG supraglottic airway device as a conduit for flexible bronchoscope-guided tracheal intubation results in a success rate equivalent to the use of the LMA-FT. However, the IG allows for shorter intubation times and a better visualization of the glottic opening compared with the LMA-FT.

Impact of pregabalin on the occurrence of postthoracotomy pain syndrome: a randomized trial.

BACKGROUND: Postthoracotomy pain syndrome (PTPS) is a frequent cause of chronic postoperative pain. Pregabalin might reduce the incidence of chronic postoperative pain. The goal of this study was to evaluate the impact of perioperative pregabalin on the occurrence of PTPS, defined as any surgical site pain 3 months after surgery. METHODS: We conducted a randomized, placebo-controlled, double-blind trial in patients undergoing elective thoracotomy. Patients received either pregabalin 150 mg orally twice a day initiated 1 hour before thoracotomy and continued until 4 days after thoracotomy (10 doses total) or a placebo using the same protocol. All patients received preincision thoracic epidural analgesia. Postthoracotomy pain syndrome was evaluated using the Brief Pain Inventory questionnaire through a telephone interview. Secondary outcomes included evaluation of neuropathic characteristics through the Leeds Assessment of Neuropathic Symptoms and Signs questionnaire, analgesic use 3 months after surgery, and evaluation of acute postoperative pain and opioid consumption. RESULTS: One hundred fourteen patients were randomized, and 99 patients completed the study (placebo, n = 49; pregabalin, n = 50). Postthoracotomy pain syndrome occurred in 49 (49.5%) of 99 patients and more frequently in the pregabalin group (31/50 [62%] vs 18/49 [37%] in the placebo group, P = 0.01). However, among patients with PTPS, those in the pregabalin group required significantly less analgesics, reported less moderate to severe average pain, and presented significantly less neuropathic characteristics than patients in the placebo group 3 months after surgery. CONCLUSIONS: Pregabalin did not reduce the incidence of PTPS in this study. Future research on PTPS should focus on the impact of regional analgesia on central sensitization.

A comparison of two doses of mannitol on brain relaxation during supratentorial brain tumor craniotomy: a randomized trial.

BACKGROUND: Twenty percent mannitol is widely used to reduce brain bulk and facilitate the surgical approach in intracranial surgery. However, a dose-response relationship has not yet been established. In this study, we compared the effects of 0.7 and 1.4 g·kg(-1) mannitol on brain relaxation during elective supratentorial brain tumor surgery. METHODS: In this prospective, randomized, double-blind study, we enrolled 80 patients undergoing supratentorial craniotomy for tumor resection. Patients were assigned to receive 0.7 g·kg(-1) (group L) or 1.4 g·kg(-1) (group H) of 20% mannitol at surgical incision. Brain relaxation was assessed immediately after opening of the dura on a scale ranging from 1 to 4 (1 = perfectly relaxed, 2 = satisfactorily relaxed, 3 = firm brain, 4 = bulging brain). RESULTS: There was no significant difference between the 2 groups regarding age, sex, body mass index, and brain tumor localization or size. In group L 52.5% of patients and in group H 77.5% of patients presented a midline shift (P = 0.03). The median scores of brain relaxation (interquantile range) were 2.0 (1.75-3) and 2.0 (1-3) (P = 0.16 for patients in group L and H, respectively). We then used a proportional odds model to adjust for this unbalanced distribution and to assess the group effect (low-dose versus high-dose mannitol) on brain relaxation scores. When adjusted for the presence of midline shift, the use of a higher dose of mannitol resulted in an odds ratio of 2.5 (P = 0.03). This indicates that, considering the effect of a midline shift, the odds of having a 1-level improvement in relaxation score in patients who received a higher dose of mannitol (group H) was 2.5 times as large as the odds for the low-dose group. The odds ratio of 0.29 (P = 0.007) for the midline shift indicates that its occurrence was associated with a higher probability of a lower relaxation score, on average. CONCLUSION: In this study, we show that 1.4 g·kg(-1) of 20% mannitol results in equivalent brain relaxation scores as 0.7 g·kg(-1) in patients undergoing craniotomy for supratentorial brain tumor. When corrected for the presence of midline shift, this study reveals that patients in the high-dose group had significantly more chances of obtaining a better relaxation score compared with the lower-dose group.

Postoperative anemia does not impede functional outcome and quality of life early after hip and knee arthroplasties.

BACKGROUND: Clinicians have adopted a restrictive transfusion threshold (75-80 g/L) after major orthopedic surgery. Anemia may be associated with a decrease in postoperative vigor. We hypothesize that, in these patients, a threshold hemoglobin (Hb) concentration exists below which functional recovery and quality of life (QoL) become difficult. STUDY DESIGN AND METHODS: A prospective, observational cohort study in 305 patients 60 years or older undergoing a total hip or knee arthroplasty was conducted. Major outcome variables were distance walked in 6 minutes (6MWT), score on the Borg Scale for perception of effort, maximal dominant hand strength, and Short Form 36 (SF-36) QoL assessment in the preoperative and early postoperative periods. Patients were categorized according to their Hb level the day of the postoperative 6MWT (≤ 80, 81-90, 91-100, and >100 g/L). RESULTS: There was no difference between Hb groups in the decrease of the distance walked preoperatively versus postoperatively. For both moments of observation, the 6MWT was not significantly different between Hb groups (p = 0.190). Similar results were found with perception of effort, maximal dominant hand strength, and SF-36 QoL assessment scores. In a regression model, the decrease in Hb concentration could explain only 1.9% of the total variation observed in the 6MWT (p = 0.008). CONCLUSION: Moderate anemia is not associated with an impaired functional recovery or QoL in the immediate postoperative period after major arthroplasties. Further studies will be required to determine the long-term consequences of a restrictive transfusion strategy in these patients.

Tracheal intubation through the I-gel™ supraglottic airway versus the LMA Fastrach™: a randomized controlled trial.

BACKGROUND: The i-gel™ is a supraglottic airway device not requiring inflation of a cuff for lung ventilation. Its design allows for unobstructed passage of a tracheal tube and previous studies have demonstrated a favorable alignment with the glottic inlet. In this prospective randomized study, we compared the success rate of blind tracheal intubation using the i-gel and the laryngeal mask airway (LMA) Fastrach™. METHODS: One hundred sixty patients requiring general anesthesia and airway management were randomized to tracheal intubation using the i-gel or the LMA Fastrach. After induction of general anesthesia, the allocated device was inserted and adequate lung ventilation was confirmed. Blind tracheal intubation was then attempted. First attempt and overall tracheal intubation success rates were evaluated and tracheal intubation times were measured. RESULTS: Eighty patients were recruited in each study group. Successful tracheal intubation was obtained on the first attempt in 69% of patients with the i-gel and 74% of patients with the LMA Fastrach (95% confidence interval [CI] of difference, -9% to 19%, P = 0.60). The overall intubation success rate was lower using the i-gel than it was using the LMA Fastrach (73% vs 91%, 95% CI of difference, 7% to 31%, P < 0.0001). CONCLUSIONS: On first attempts, successful blind tracheal intubation was obtained at comparable rates using the i-gel and the LMA Fastrach. However, when the first attempt was unsuccessful, subsequent attempts through the i-gel did not significantly increase tracheal intubation success rate. The LMA Fastrach yielded a higher overall intubation success rate.

Superficial cervical plexus block for transitional analgesia in infratentorial and occipital craniotomy: a randomized trial.

BACKGROUND: In this study, we compared the quality of transitional analgesia provided by bilateral superficial cervical plexus block (SCPB) or morphine following a remifentanil-based anesthesia for infratentorial or occipital craniotomy. METHODS: In this randomized controlled and double-blind study, 30 patients scheduled for infratentorial or occipital craniotomy were divided randomly into two groups: group morphine (morphine 0.1 mg·kg⁻¹ iv after dural closure and a SCPB performed with 20 mL of 0.9% saline at the end of the surgery) or group block (10 mL of 0.9% saline iv instead of morphine after dural closure and a SCPB performed with 20 mL of a 1:1 mixture of 0.5% bupivacaine and 2% lidocaine at the end of the surgery). Postoperative pain was assessed at one, two, four, eight, 12, 16, and 24 hr using an 11-point (0-10) numerical rating scale (NRS). Analgesia was provided with subcutaneous codeine. RESULTS: Average NRS scores were similar between the two groups at each time interval over the study period. The average scores (with 95% confidence interval) were 3.9 (3.4-4.4) and 4.3 (3.8-4.9) for the block and morphine groups, respectively (P = 0.25). The delay before administration of the first dose of codeine was not statistically different between the two groups: 25 min (5-2,880) vs 21.5 min (5-90), median and range for the block and morphine groups, respectively. The incidence of nausea and vomiting was similar between the two groups. CONCLUSION: Bilateral superficial cervical plexus block provides transitional analgesia that is clinically equivalent to morphine following remifentanil-based anesthesia in patients undergoing occipital or infratentorial craniotomies.

Red blood cell transfusion practice in elective orthopedic surgery: a multicenter cohort study.

BACKGROUND: The indications for red blood cell (RBC) transfusions remain unclear despite published guidelines. Our hypothesis was that the transfusion practice varies inside the Centre hospitalier de l'Université de Montréal (CHUM). STUDY DESIGN AND METHODS: A total of 701 charts of patients who underwent a knee or hip arthroplasty or prosthesis revision in three hospitals of the CHUM were reviewed. Demography, hemoglobin (Hb) concentrations, details on transfusions, and postoperative adverse events (AEs) were collected up until discharge. The primary outcome was the presence or absence of RBC transfusion. Secondary outcomes were the nadir Hb, number of units transfused, discharge Hb, blood losses, and postoperative AEs. RESULTS: The rate of postoperative transfusion was 29%. We found no significant difference between odds ratios of each site for sex, coronary artery disease, chronic heart failure, type of procedure, American Society of Anesthesiologists physical status, weight, height, body mass index, body surface area, and estimated blood volume. Overall, patients were transfused at a Hb between 75 and 80g/L. Eighty-five percent of postoperative transfusions could be predicted using only nadir Hb and adding patient characteristics did not substantially improve the model (86.1%). Discharge Hb was below 100g/L in 66% of patients. CONCLUSIONS: There was no difference among hospitals regarding the way RBC transfusions are used. Our data suggest that physicians mainly based their decision to transfuse on a single variable, the Hb concentration, with the use of a restrictive strategy. Future trials should focus on the optimal transfusion trigger to adopt in major orthopedic surgery.

The effect of sedation on intracranial pressure in patients with an intracranial space-occupying lesion: remifentanil versus propofol.

BACKGROUND: In this study, we compared the effect of light sedation with remifentanil versus propofol on intracranial (ICP) and cerebral perfusion pressure (CPP) of patients undergoing stereotactic brain tumor biopsy under regional anesthesia. METHODS: This was a prospective, open-label, randomized, and controlled study. Forty patients undergoing stereotactic brain tumor biopsy under regional anesthesia were randomized into two groups to receive remifentanil or propofol titrated to a level of four on the modified Assessment of Alertness/Sedation Scale. ICP was measured via the biopsy needle. RESULTS: At the targeted level of sedation, the rates of infusion for remifentanil and propofol were, respectively, 4.2 +/- 1.8 microg x kg(-1) x h(-1) and 4.3 +/- 2.5 mg x kg(-1) x h(-1). At the time of ICP measurement, patients in the remifentanil group had a slower respiratory rate (11/min +/- 3 vs 15 per min +/- 3, P = 0.0001) and a higher PCO2 (48.3 +/- 6.2 mm Hg vs 43.1 +/- 5.5 mm Hg, P = 0.009) than patients in the propofol group. The mean was similar for both groups, 19.0 +/- 11.9 mm Hg vs 16.4 +/- 11.1 mm Hg for remifentanil and propofol, respectively (P = 0.48). Higher mean arterial blood pressure in the remifentanil group (101.1 +/- 13.7 mm Hg vs 85.8 +/- 12.7 mm Hg, P = 0.0008) resulted in a higher CPP than the propofol group: 82.0 +/- 19.0 mm Hg vs 69.5 +/- 17.0 +/- 19.0 mm Hg (P = 0.03). CONCLUSION: Light sedation with remifentanil does not result in a higher ICP than propofol in patients undergoing stereotactic brain tumor biopsy. CPP might be better preserved with remifentanil.