Prevention of hypotension after induction of general anesthesia using point-of-care ultrasound to guide fluid management: a randomized controlled trial.

PURPOSE: Hypotension after induction of general anesthesia (GAIH) is common and is associated with postoperative complications including increased mortality. Collapsibility of the inferior vena cava (IVC) has good performance in predicting GAIH; however, there is limited evidence whether a preoperative fluid bolus in patients with a collapsible IVC can prevent this drop in blood pressure. METHODS: We conducted a single-centre randomized controlled trial with adult patients scheduled to undergo elective noncardiac surgery under general anesthesia (GA). Patients underwent a preoperative point-of-care ultrasound scan (POCUS) to identify those with a collapsible IVC (IVC collapsibility index ≥ 43%). Individuals with a collapsible IVC were randomized to receive a preoperative 500 mL fluid bolus or routine care (control group). Surgical and anesthesia teams were blinded to the results of the scan and group allocation. Hypotension after induction of GA was defined as the use of vasopressors/inotropes or a decrease in mean arterial pressure < 65 mm Hg or > 25% from baseline within 20 min of induction of GA. RESULTS: Forty patients (20 in each group) were included. The rate of hypotension after induction of GA was significantly reduced in those receiving preoperative fluids (9/20, 45% vs 17/20, 85%; relative risk, 0.53; 95% confidence interval, 0.32 to 0.89; P = 0.02). The mean (standard deviation) time to complete POCUS was 4 (2) min, and the duration of fluid bolus administration was 14 (5) min. Neither surgical delays nor adverse events occurred as a result of the study intervention. CONCLUSION: A preoperative fluid bolus in patients with a collapsible IVC reduced the incidence of GAIH without associated adverse effects. STUDY REGISTRATION: ClinicalTrials.gov (NCT05424510); first submitted 15 June 2022.

RéSUMé: OBJECTIF: L'hypotension après induction de l'anesthésie générale (AG) est fréquente et est associée à des complications postopératoires, notamment à une augmentation de la mortalité. La collapsibilité de la veine cave inférieure (VCI) a été utilisée avec succès pour prédire la l'hypotension post-induction de l'AG; cependant, il existe peu de données probantes qu'un bolus liquidien préopératoire chez les patient·es présentant une collapsibilité de la VCI puisse prévenir cette baisse de la tension artérielle. MéTHODE: Nous avons réalisé une étude randomisée contrôlée monocentrique auprès de patient·es adultes devant bénéficier d'une chirurgie non cardiaque non urgente sous anesthésie générale. Les patient·es ont passé une échographie préopératoire ciblée (POCUS) pour identifier les personnes présentant une collapsibilité de la VCI (indice de collapsibilité de la VCI ≥ 43 %). Les personnes présentant une collapsibilité de la VCI ont été randomisées à recevoir un bolus de liquide préopératoire de 500 mL ou des soins de routine (groupe témoin). Les équipes chirurgicales et d'anesthésie ne connaissaient pas les résultats de l'examen ni l'attribution des groupes. L'hypotension après induction de l'AG a été définie comme l'utilisation de vasopresseurs/inotropes ou une diminution de la tension artérielle moyenne < 65 mm Hg ou > 25 % par rapport aux valeurs de base dans les 20 minutes suivant l'induction de l'AG. RéSULTATS: Quarante patient·es (20 dans chaque groupe) ont été inclus·es. Le taux d'hypotension après induction de l'AG était significativement réduit chez les personnes recevant des liquides préopératoires (9/20, 45 % vs 17/20, 85 %; risque relatif, 0,53; intervalle de confiance à 95 %, 0,32 à 0,89; P = 0,02). Le temps moyen (écart type) pour compléter l'échographie ciblée était de 4 (2) min, et la durée de l'administration du bolus liquidien était de 14 (5) min. Ni retards chirurgicaux ni effets indésirables ne sont survenus à la suite de l'intervention à l'étude. CONCLUSION: Un bolus liquidien préopératoire chez les patient·es présentant une collapsibilité de la VCI a réduit l'incidence d'hypotension après l'induction de l'anesthésie générale sans effets indésirables associés. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT05424510); première soumission le 15 juin 2022.

The Effect of Prolonged Face Mask Ventilation on Gastric Insufflation: A Prospective Observational Study.

BACKGROUND: Pulmonary aspiration is a potentially lethal perioperative complication that can be precipitated by gastric insufflation. Face mask ventilation (FMV), a ubiquitous anesthetic procedure, can cause gastric insufflation. FMV with an inspiratory pressure of 15 cm H2O provides the best balance between adequate pulmonary ventilation and a low probability of gastric insufflation. There is no data about the effects of FMV > 120 seconds. OBJECTIVES: To investigate the effect of prolonged FMV on gastric insufflation. METHODS: We conducted a prospective observational study at a tertiary medical center with female patients who underwent oocyte retrieval surgery under general anesthesia FMV. Pre- and postoperative gastric ultrasound examinations measured the gastric antral cross-sectional area to detect gastric insufflation. Pressure-controlled FMV with an inspiratory pressure of 15 cm H2O was continued from the anesthesia induction until the end of the surgery. RESULTS: The study comprised 49 patients. Baseline preoperative gastric ultrasound demonstrated optimal and good image quality. All supine measurements were feasible. The median duration of FMV was 13 minutes (interquartile range 9-18). In the postoperative period, gastric insufflation was detected in only 2 of 49 patients (4.1%). There was no association between the duration of FMV and delta gastric antral cross-sectional area (ß -0.01; 95% confidence interval -0.04 to 0.01, P = 0.31). CONCLUSIONS: Pressure-controlled FMV with an inspiratory pressure of 15 cm H2O carries a low incidence of gastric insufflations, not only as a bridge to a definitive airway but as an alternative ventilation method for relatively short procedures in selective populations.

Gastric Volume and Antral Area in the Fasting State: A Meta-analysis of Individual Patient Data.

BACKGROUND: Pulmonary aspiration of gastric content is a serious anesthetic complication. Gastric point-of-care ultrasound can determine the type and volume of gastric content when clinical information is equivocal. However, a cutoff value of either antral cross-sectional area or volume that may be considered as the upper limit of normal in fasting subjects is still controversial. The aim of this study is to characterize the distribution of baseline antral area and volume in fasting adult subjects and to identify an upper limit (95th percentile) of these distributions. METHODS: The authors conducted a meta-analysis of individual participant data of primary studies from an academic research network of investigators collaborating in gastric ultrasound. Studies between January 2009 and December 2020 were included. RESULTS: Twelve primary studies met inclusion criteria and were included in the analysis with a sample size of 1,203 subjects. The 95th percentile of area values (measured in the right lateral decubitus) was 9.9 cm2 (95% CI, 9.4 to 10.4), and of volume, 2.3 ml/kg (95% CI, 2.3 to 2.4). In addition, an antrum grade 0 or 1 indicates a 98% probability of an antral area below the 95th percentile. CONCLUSIONS: An area of 10 cm2 measured in the right lateral decubitus could be a simple, data-driven upper limit of antral area that could serve as a surrogate of upper limit of normal gastric volume values in fasting adults. These results are limited by the highly selected sampling of the studies included.

Use of a Novel Three-Dimensional Model to Teach Ultrasound-guided Subclavian Vein Cannulation.

Background: Central venous cannulation is an essential skill in perioperative and critical care medicine. Ultrasound guidance is the standard of care for femoral and internal jugular vein access, with the subclavian vein being perceived to be less amenable to ultrasound-guided (UG) insertion, resulting in a lack of procedural competency and low cannulation rate. There is a paucity of resources and a lack of experience among staff physicians to effectively instruct trainees. Simulation-based medical education has the potential to help maintain high-stakes, infrequently performed skills and counteract possible unrecognized skill decline. We aimed to create a novel, low-cost, high-fidelity three-dimensional (3D) model for UG subclavian vein (UG-SCV) access with an accompanying curriculum to improve this important skill. Methods: A curriculum was created consisting of preparatory material reviewing UG-SCV access, followed by an in-person didactic lecture focusing on ultrasound use and management of complications and a deliberate practice session scanning volunteers and practicing UG vascular puncture on a 3D model. A qualitative usability test design was used to assess the validity of the curriculum in trainees with advanced vascular access skills (anesthesiologists). Participants were second-year anesthesia residents, anesthesia fellows, and staff physicians. Focus groups conducted after each session explored the face validity of the model and curriculum. By applying a usability design, the curriculum was optimized and finalized. Results: Between September 2020 and February 2021, 28 participants tested the curriculum. The focus groups ensured that the curriculum achieved its objective, with iterative changes made after each session in a quality improvement framework Plan-Do-Study-Act approach. After the third cycle, minimal changes were suggested, and the curriculum and 3D model were finalized. An additional group of participants was used to ensure that no new input would help improve the curriculum further. Conclusions: A focused curriculum for enhancing skills in UG-SCV cannulation using a novel 3D model was successfully implemented and validated through a usability test design. This curriculum is better targeted for practitioners experienced in central venous access to master a subclavian approach and maintain their skill level.

The effect of preoperative anxiety and ovarian stimulation on gastric antrum size: a prospective observational study.

Pulmonary aspiration is a potentially lethal perioperative complication related to gastric size and contents. Several perioperative factors are believed to increase gastric size, while others are less studied. This prospective observational study aimed to investigate the effect of preoperative anxiety and hormone-induced ovarian stimulation on gastric size examined by gastric ultrasound. We recruited 49 female patients undergoing hormone-induced ovarian stimulation and oocyte retrieval for in vitro fertilization at Rabin Medical Centre, Petah Tikva, Israel. Preoperatively, women ranked their anxiety level using a verbal numeric anxiety score (VNS). In addition, we recorded the extent of ovarian stimulation and measured the antral cross-sectional area (CSA) using gastric ultrasound. There was no substantial correlation between preoperative VNS anxiety and antral CSA (p = .697). Moreover, the number of follicles, blood estradiol, and progesterone levels did not correlate with antral CSA (p = .590, p = .104, and p = .511, respectively). In conclusion, neither preoperative anxiety nor extensive ovarian stimulation affects gastric size in fasting healthy patients. However, further studies are warranted in this area to define these findings better. Trial registration: Clinicaltrials.gov, identifier: NCT04833530.

Validation of a novel patient satisfaction questionnaire for preoperative fasting in cataract surgery: a discrimination analysis.

OBJECTIVE: Preoperative fasting is routinely performed to prevent anaesthesia-related pulmonary aspiration. To capture patients' experiences with preoperative fasting, a 13-item questionnaire was developed and validated using Rasch analysis and shortened to 6 items. This extension study aims to assess this questionnaire's ability to discriminate between participants with a short versus long duration of fasting and early versus late day surgery. DESIGN: Single-centred cross-sectional study. PARTICIPANTS: Subjects were recruited via consecutive sampling of cataract patients on surgery day at Kensington Eye Institute in Toronto from February to December 2019. METHODS: A validated preoperative fasting questionnaire was administered. Discriminative ability was assessed by comparing responses in patients scheduled for surgery in the morning (8:00 am-12:00 pm) versus afternoon (12:00 pm-3:30 pm) and fasting for short (≤8 hours) versus long (>8 hours) duration. Diagnostic ability of the 6-item questionnaire relative to the 13-item questionnaire was assessed with receiver operating characteristics curve analysis. RESULTS: A total of 164 patients (mean age 70.8 ± 10.0 years; 57% female) were included. Total scores of patients having surgery in the morning were greater (i.e., less fasting-related burden) than in the afternoon (p = 0.04). There was no significant difference in scores between patients fasting for a short versus long duration (p > 0.05). Receiver operating characteristics curve analysis showed excellent diagnostic ability of the 6-item questionnaire relative to the 13-item version (area under the curve = 0.964). CONCLUSION: The 6-item questionnaire for fasting-related burden has excellent discriminative ability between early versus late surgery patients. The time fasting while awake may be a more relevant predictor of fasting-related burden relative to the total duration of fasting.

Color flow Doppler in spinal ultrasound: a novel technique for assessment of catheter position in labor epidurals.

BACKGROUND: Ultrasound is commonly used to facilitate epidural catheter placement. However, data are lacking regarding its potential to confirm its position in the epidural space. Our aim was to visualize flow in the epidural space of patients receiving epidural analgesia for labor using color flow Doppler ultrasound. METHODS: We conducted a prospective observational cohort study that included patients who had delivered vaginally under epidural analgesia. We used a 5-2 mHz curvilinear probe in a left and right paramedian longitudinal oblique view to visualize the anterior and posterior complex at the interspace of epidural catheter insertion, one and two interspaces above and below. At each window, the color flow Doppler function was used to visualize flow within the epidural space on injection of normal saline (1 mL). If no flow was visualized at any interspace, one assessment at the level of insertion was repeated with a 1 mL air/saline mixture. We studied a convenience sample size of 40 patients. RESULTS: We visualized flow in the epidural space in all 40 patients. Flow was visualized on injection of 1 mL of saline in 37/40 patients (93%). In the remaining 3/40 patients (7%), flow was visualized with an air/saline mixture. Flow on injection of saline was visualized only at the interspace of insertion in 26/37 patients (70%), at the interspace of insertion and one interspace above in 10/37 (27%), or only at one interspace above in 1/37 (3%). Flow was visualized only on the left or on the right paramedian view in 19/37 patients (51%), despite a symmetrical sensory block in all patients. CONCLUSION: Color flow Doppler ultrasound is a feasible and fast way to determine flow in the epidural space in the obstetric population. Its potential clinical uses are confirmation of the epidural catheter position after placement, as well as troubleshooting of unsatisfactory epidural analgesia. Interestingly, our results suggest that epidural catheters predominantly remain at the interspace of insertion. TRIAL REGISTRATION NUMBER: NCT05126745.

What are we missing? The quality of intraoperative handover before and after introduction of a checklist.

PURPOSE: Intraoperative handovers are common in anesthesia practice and are associated with increased patient morbidity and mortality. Checklists may improve transfer of information during handovers. This before-and-after study sought to examine the effect of a checklist on intraoperative handover. We hypothesized that introducing a handover checklist would improve our primary outcome of completeness of data transfer. METHODS: From February to August 2016, anesthesia providers (residents, fellows, and consultants) at a single tertiary academic center participated in a handover study. Baseline handovers between anesthesia care providers were videotaped, analyzed, and compared with anesthetic records. An intraoperative handover checklist was then introduced, and handovers completed with it were videotaped. The completeness of handovers was compared between the baseline routine and checklist groups. The primary outcome was completeness of information transfer. RESULTS: Sixty-seven anesthesia providers participated in the study. Use of the intraoperative handover checklist improved completeness of handover by 6% (95% confidence interval [CI], 2 to 10; P < 0.01). There was no relationship observed between the provider (consultants/fellows vs resident) of the handovers and the degree of completeness (95% CI, 3 to 8; P = 0.33). Complexity had a significant impact on the handover completeness with low or high complexity cases more completely handed over than those of medium complexity both before and after the intervention-a 6% increase for low complexity (95% CI, 1 to 11; P = 0.02) and a 9% increase for high complexity (95% CI, 3 to 14; P < 0.01). CONCLUSION: Use of a checklist during intraoperative handovers improved completeness of data transfer. Handover checklists should be considered to improve handover completeness.

RéSUMé: OBJECTIF: Les transferts peropératoires sont fréquents dans la pratique de l'anesthésie et sont associés à une augmentation de la morbidité et de la mortalité des patients. Les listes de vérification pourraient améliorer le transfert d'informations pendant les transitions. Cette étude avant-après a cherché à examiner l'effet d'une liste de vérification sur les transferts peropératoires. Nous avons émis l'hypothèse que l'introduction d'une liste de vérification de transfert améliorerait notre critère d'évaluation principal, nommément la complétude du transfert des informations. MéTHODE: De février à août 2016, des prestataires d'anesthésie (résidents, fellows et consultants) d'un seul centre universitaire tertiaire ont participé à une étude sur les transferts. Les transferts de base entre les fournisseurs de soins d'anesthésie ont été filmés, analysés et comparés aux dossiers d'anesthésie. Une liste de contrôle de transfert peropératoire a ensuite été introduite, et les transferts réalisés avec celle-ci ont été filmés. La complétude des transferts a été comparée entre les groupes faisant un transfert normal de base et ceux utilisant la liste de vérification. Le critère d'évaluation principal était la complétude du transfert d'informations. RéSULTATS: Soixante-sept fournisseurs d'anesthésie ont participé à l'étude. L'utilisation de la liste de vérification de transfert peropératoire a amélioré la complétude du transfert de 6 % (intervalle de confiance [IC] à 95 %, 2 à 10; P < 0,01). Aucune relation n'a été observée entre le fournisseur (consultants/fellows) vs résidents) responsable des transferts et le degré de complétude du transfert (IC 95 %, 3 à 8; P = 0,33). La complexité a eu un impact significatif sur la complétude du transfert, les cas de basse ou haute complexité étant transférés de manière plus complète que les cas de complexité moyenne, tant avant qu'après l'intervention ­ avec une augmentation de 6 % pour les cas de faible complexité (IC 95 %, 1 à 11; P = 0,02) et une augmentation de 9 % pour les cas de complexité élevée (IC 95 %, 3 à 14; P < 0,01). CONCLUSION: L'utilisation d'une liste de vérification lors des transferts peropératoires a amélioré la complétude du transfert des informations. Les listes de vérification de transfert devraient être envisagées pour améliorer la complétude des transferts.

Adapting obstetric and neonatal services during the COVID-19 pandemic: a scoping review.

BACKGROUND: The provision of care to pregnant persons and neonates must continue through pandemics. To maintain quality of care, while minimizing physical contact during the Severe Acute Respiratory Syndrome-related Coronavirus-2 (SARS-CoV2) pandemic, hospitals and international organizations issued recommendations on maternity and neonatal care delivery and restructuring of clinical and academic services. Early in the pandemic, recommendations relied on expert opinion, and offered a one-size-fits-all set of guidelines. Our aim was to examine these recommendations and provide the rationale and context to guide clinicians, administrators, educators, and researchers, on how to adapt maternity and neonatal services during the pandemic, regardless of jurisdiction. METHOD: Our initial database search used Medical subject headings and free-text search terms related to coronavirus infections, pregnancy and neonatology, and summarized relevant recommendations from international society guidelines. Subsequent targeted searches to December 30, 2020, included relevant publications in general medical and obstetric journals, and updated society recommendations. RESULTS: We identified 846 titles and abstracts, of which 105 English-language publications fulfilled eligibility criteria and were included in our study. A multidisciplinary team representing clinicians from various disciplines, academics, administrators and training program directors critically appraised the literature to collate recommendations by multiple jurisdictions, including a quaternary care Canadian hospital, to provide context and rationale for viable options. INTERPRETATION: There are different schools of thought regarding effective practices in obstetric and neonatal services. Our critical review presents the rationale to effectively modify services, based on the phase of the pandemic, the prevalence of infection in the population, and resource availability.

Programmed intermittent epidural bolus for labour analgesia: a randomized controlled trial comparing bolus delivery speeds of 125 mL·hr-1 versus 250 mL·hr-1.

PURPOSE: Programmed intermittent epidural bolus (PIEB) provides better analgesia for labour pain than continuous epidural infusion does. Nevertheless, commonly used PIEB regimens are associated with high sensory block. We hypothesized that a PIEB technique with slower bolus delivery speed would produce lower sensory levels. METHODS: We recruited term nulliparous women with singleton pregnancies during the first stage of labour. All participants had an American Society of Anesthesiologists Physical Status score of II-III, had epidural catheters placed at L3/4, and had epidural analgesia maintained with PIEB 10 mL every 40 min using 0.0625% bupivacaine with fentanyl 2 µg·mL-1. Women were randomized to receive PIEB delivered at 250 mL·hr-1 (G250) or 125 mL·hr-1 (G125). The study was completed six hours after the loading dose or at full cervical dilatation, whichever occurred first. The primary outcome was the presence of sensory block to ice ≥ T6 in at least one assessment during the study period (maximum six hours). RESULTS: We analyzed data from 90 women. The proportion of women presenting sensory block ≥ T6 at any time was not different between G125 and G250 groups (60.0% vs 64.4%; difference, -4.4%; 95% confidence interval [CI], -24.5 to 15.6; P = 0.66). The median [interquartile range] highest sensory block level was also not different between G125 and G250 groups (T6 [T7-T5] vs T5 [T7-T5], P = 0.39). Women in the G125 group had a lower incidence of hypotension than women in the G250 group did (11.1% vs 33.3%; difference, -22.2%; 95% CI, -38.8 to -5.67; P = 0.01). Quality of analgesia and patient satisfaction were not different between groups. CONCLUSION: The maintenance of epidural analgesia with a PIEB delivery speed of 125 mL·hr-1 did not produce lower sensory block levels when compared with 250 mL·hr-1. The slower injection speed regimen was associated with lower incidence of hypotension, but this secondary finding warrants confirmation in a future trial. TRIAL REGISTRATION: www.ClinicalTrials.gov (NCT03236298); registered 1 August 2017.

RéSUMé: OBJECTIF: L'administration programmée intermittente de bolus périduraux (PIEB, pour programmed intermittent epidural bolus) fournit une meilleure analgésie pour la douleur du travail que l'analgésie péridurale par perfusion continue. Néanmoins, les régimes de PIEB couramment utilisés sont associés à un bloc sensoriel élevé. Nous avons émis l'hypothèse qu'une technique de PIEB avec une vitesse d'administration plus lente du bolus produirait des niveaux sensoriels inférieurs. MéTHODE: Nous avons recruté des femmes nullipares à terme ayant des grossesses uniques au cours de la première étape du travail obstétrical. Toutes les participantes avaient un score de statut physique II-III de l'American Society of Anesthesiologists, des cathéters périduraux placés au niveau L3/4 et une analgésie péridurale maintenue avec des PIEB de 10 mL de bupivacaïne 0,0625 % et de 2 µg·mL-1 de fentanyl, administrés toutes les 40 minutes. Les femmes ont été randomisées à recevoir des PIEB administrés à une vitesse de 250 mL·h-1 (G250) ou 125 mL·h-1 (G125). L'étude se terminait six heures après la dose de charge ou lors de la dilatation cervicale complète, selon la première éventualité. Le critère d'évaluation principal était la présence d'un bloc sensoriel à la glace ≥ T6 lors d'au moins une évaluation au cours de la période à l'étude (pour un maximum de six heures). RéSULTATS: Nous avons analysé les données de 90 femmes. La proportion de femmes présentant un bloc sensoriel ≥ T6 à tout moment n'était pas différente entre les groupes G125 et G250 (60,0 % vs 64,4 %; différence, -4,4 %; intervalle de confiance [IC] à 95 %, -24,5 à 15,6; P = 0,66). Le niveau médian [écart interquartile] le plus élevé de bloc sensoriel n'était pas non plus différent entre les groupes G125 et G250 (T6 [T7-T5] vs T5 [T7-T5], P = 0,39). Les femmes du groupe G125 avaient une incidence d'hypotension plus faible que les femmes du groupe G250 (11,1 % vs 33,3 %; différence, -22,2 %; IC 95 %, -38,8 à -5,67; P = 0,01). La qualité de l'analgésie et la satisfaction des patientes n'étaient pas différentes d'un groupe à l'autre. CONCLUSION: Le maintien de l'analgésie péridurale avec une vitesse d'administration des PIEB de 125 mL·h-1 n'a pas entraîné de taux de blocs sensoriels inférieurs par rapport à une vitesse de 250 mL·h-1. Le régime de vitesse d'injection plus lente a été associé à une incidence plus faible d'hypotension, mais cette constatation secondaire mérite d'être confirmée dans une étude future. ENREGISTREMENT DE L'éTUDE: www.ClinicalTrials.gov (NCT03236298); enregistrée le 1er août 2017.

Predicting pain after Cesarean delivery: pressure algometry, temporal summation, three-item questionnaire.

PURPOSE: Approximately one in five women will experience severe postoperative pain after Cesarean delivery (CD). Previously, a bedside three-item questionnaire (3-IQ) has shown to predict women experiencing higher evoked pain intensity after CD, with an area under the receiver operator characteristics (ROC) curve of 0.72. We hypothesized that the addition of psychophysical pain tests to the existing 3-IQ would improve the ability to predict severe pain in women undergoing elective CD under spinal anesthesia METHODS: This was a prospective cohort study on women undergoing elective CD under spinal anesthesia. Women were assessed preoperatively using the 3-IQ, pressure algometry (PA) and mechanical temporal summation (TS) response. All women received standard perioperative care, including a multimodal analgesia regimen that included intrathecal fentanyl and morphine. A 0-100 mm visual analogue scale (VAS) was used to assess the severity of pain at rest (VASr) and on movement (VASm) at 24 and 48 hr after surgery. Patient satisfaction and opioid consumption were also recorded. We performed ROC curve analyses to assess whether we could improve the ability to predict our primary outcome of severe pain on movement at 24 hr (VASm24 ≥ 70). RESULTS: We studied 195 women. Median [interquartile range] VASm24 was 53 [32-72] and 28% of patients experienced a VASm24 ≥ 70. The ability to predict a VASm24 ≥ 70 assessed by the area under the ROC curve was 0.64 using the 3-IQ and 0.67 using the 3-IQ combined with TS and PA. CONCLUSION: The addition of PA and TS to the 3-IQ model resulted in a predictive model that performed similarly to the 3-IQ model alone. Further research is warranted in this area to better predict women at risk of severe pain post CD.

RéSUMé: OBJECTIF: Environ une femme sur cinq souffrira de douleur postopératoire sévère après un accouchement par césarienne. Un questionnaire à trois critères (Q3C) administré au chevet de la patiente a déjà été utilisé pour prédire quelles femmes éprouveraient une intensité de douleur évoquée plus élevée après une césarienne, avec une aire sous la courbe ROC de 0,72. Nous avons émis l'hypothèse que l'ajout de tests psychophysiques de douleur au Q3C existant améliorerait notre capacité à prédire la douleur sévère chez les femmes bénéficiant d'une césarienne élective sous rachianesthésie. MéTHODE: Il s'agissait d'une étude de cohorte prospective auprès de femmes bénéficiant d'une césarienne élective sous rachianesthésie. Les femmes ont été évaluées en préopératoire à l'aide du Q3C, de l'algométrie par pression (AP) et de la réponse à une sommation temporale (ST) mécanique. Toutes les femmes ont bénéficié des soins périopératoires standard, ainsi que d'un régime d'analgésie multimodal incluant fentanyl et morphine intrathécaux. Une échelle visuelle analogique (EVA) de 0 à 100 mm a été utilisée pour évaluer la sévérité de la douleur au repos (EVAr) et en mouvement (EVAm) à 24 et 48 heures après la chirurgie. La satisfaction des patientes et la consommation d'opioïdes ont également été enregistrées. Nous avons effectué des analyses de la courbe ROC pour déterminer s'il nous était possible d'améliorer notre capacité à prédire notre critère d'évaluation principal, soit la douleur sévère à la mobilisation à 24 heures (EVAm24 ≥ 70). RéSULTATS: Nous avons étudié 195 femmes. L'EVAm 24 médiane [écart interquartile] était de 53 [32-72] et 28 % des patientes ont noté un score sur l'EVAm24 ≥ 70. La capacité à prédire un score sur l'EVAm24 ≥ 70 tel qu'évalué par la surface sous la courbe ROC était de 0,64 en utilisant le Q3C et de 0,67 en utilisant le Q3C combiné à la ST et l'AP. CONCLUSION: L'ajout de l'AP et de la ST au modèle de Q3C a résulté en un modèle prédictif présentant une performance similaire au modèle de Q3C seul. D'autres recherches sont nécessaires dans ce domaine pour mieux prédire les femmes à risque de douleur sévères après une césarienne.

Feasibility of ultrasound-assisted lumbar punctures performed by pediatric oncologists at the point of care.

BACKGROUND: Ultrasound assistance improves success rates and reduces adverse outcomes of lumbar punctures (LPs) among adult patients in the emergency room and the operating room, but has not been evaluated in pediatric patients with cancer. Our objectives were (1) to determine whether pediatric oncologists could perform ultrasound-assisted LPs following a structured teaching curriculum, and (2) to determine the feasibility of recruiting pediatric cancer patients to a clinical trial of this procedure. METHODS: Three pediatric oncologists completed a curriculum composed of didactic teaching followed by hands-on workshops. Each learner was evaluated during 20 attempts at three ultrasound tasks using the cumulative sum method. The three pediatric oncologists then performed ultrasound assessments prior to routinely scheduled LPs. Feasibility was defined as ability to perform at least 30 ultrasound-assisted LPs within 6 months. Secondary outcomes were the proportion of successful, bloody, or traumatic LPs, time required, and perceived helpfulness of ultrasound. RESULTS: All three pediatric oncologists achieved competence in the three tasks of ultrasound scanning within 20 evaluated attempts. We recruited 62 patients within 1 month, and 58 underwent an ultrasound-assisted LP. All LPs were successful. Two LPs (4%) had ≥500 red blood cells (RBCs)/µl, and nine (16%) had ≥10 RBCs/µl. Median time to conduct the scan was 1.9 minutes (range 0.8-4.0 minutes). In 37 (64%) of the LPs, ultrasound assistance was considered helpful or very helpful. CONCLUSIONS: Pediatric oncologists readily achieved competence in ultrasound-assisted LPs, and ultrasound was commonly perceived as helpful. It is feasible to proceed to a randomized trial of this procedure in pediatric cancer.

Programmed intermittent epidural bolus for labour analgesia during first stage of labour: a sequential allocation trial to determine the effective interval time between boluses of a fixed volume of 2.5 mL of bupivacaine 0.25% plus fentanyl 8 µg·mL-1.

PURPOSE: We studied the programmed intermittent epidural bolus (PIEB) time interval between boluses of 2.5 mL of bupivacaine 0.25% with fentanyl 8 µg·mL-1 to produce effective analgesia in 90% of women (EI90) during the first stage of labour. METHODS: In a double-blind sequential allocation trial using a biased coin up-and-down design to determine the EI90, the PIEB boluses of 2.5 mL of 0.25% bupivacaine plus fentanyl 8 µg·mL-1 were delivered at varying intervals-60, 50, 40, and 30 min. The primary outcome was the adequate response of the patient to the PIEB regimen, defined as no use of supplemental analgesia for six hours or until the first stage of labour was completed, whichever came first. The secondary outcomes were the upper sensory block level to ice, motor block and hypotension. The isotonic regression with extrapolation approach was used to estimate the EI90. RESULTS: In the 20 women studied, the estimated EI90 was 20 (95% CI, 5.9 to 28.8) min. For the secondary outcomes, we classified women into those assigned to 30 min (16 women) and those assigned to more than 30 min (four women). The median upper sensory block for women in the 30-min group and more than 30 min were T6 (or T5) and T7, respectively. No participants experienced motor block. Hypotension occurred in one patient in the 30-min group. CONCLUSION: The estimated EI90 for boluses of 2.5 mL of bupivacaine 0.25% with fentanyl 8 µg·mL-1 was 20 (95% CI, 5.9 to 28.8) min. These results suggest that there is no advantage in using this regimen compared with those reported in the literature using the same dose of bupivacaine in concentrations of 0.0625% and 0.125%. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT03735771); registered 7 November 2018.

RéSUMé: OBJECTIF: Nous avons étudié l'intervalle de temps d'administration programmée de bolus périduraux (PIEB) entre des bolus de 2,5 mL de bupivacaïne 0,25 % avec 8 µg·mL−1 de fentanyl nécessaire pour procurer une analgésie efficace chez 90 % des femmes (IE90) au cours du premier stade du travail obstétrical. MéTHODE: Dans une étude de répartition séquentielle à double insu utilisant une méthodologie de tirage au sort biaisé de haut en bas pour déterminer l'IE90, des bolus PIEB de 2,5 mL de bupivacaïne 0,25 % plus 8 µg·mL−1 fentanyl ont été administrés à des intervalles variables ­ 60, 50, 40 et 30 min. Le critère d'évaluation principal était une réponse adéquate de la patiente au régime de PIEB, définie comme aucun recours à une analgésie supplémentaire pendant six heures ou jusqu'à la fin du premier stade du travail, à la première condition obtenue. Les critères d'évaluation secondaires comportaient le niveau du bloc sensitif supérieur tel qu'établi par un test de glace, ainsi que la présence d'un bloc moteur et d'hypotension. Nous avons utilisé une méthode de régression isotonique avec une approche d'extrapolation pour estimer l'IE90. RéSULTATS: Chez les 20 femmes étudiées, l'IE90 estimé était de 20 (IC 95 %, 5,9 à 28,8) min. En ce qui touche aux critères d'évaluation secondaires, nous avons catégorisé les femmes selon qu'elles étaient assignées à recevoir un bolus aux 30 min (16 femmes) ou à des intervalles de plus de 30 min (quatre femmes). Le niveau du bloc sensitif supérieur médian pour les femmes dans le groupe 30 min et plus de 30 min se situait à T6 (ou T5) et T7, respectivement. Aucune participante n'a subi de bloc moteur. Une patiente dans le groupe à 30 min a subi un épisode d'hypotension. CONCLUSION: L'IE90 estimé pour les bolus de 2,5 mL de bupivacaïne 0,25 % avec 8 µg·mL−1 de fentanyl était de 20 (IC 95 %, 5,9 à 28,8) min. Ces résultats suggèrent qu'il n'y a aucun avantage à utiliser ce régime posologique plutôt que ceux rapportés dans la littérature utilisant une même dose de bupivacaïne à des concentrations de 0,0625 % et 0,125 %. ENREGISTREMENT DE L'éTUDE: www.clinicaltrials.gov (NCT03735771); enregistrée le 7 novembre 2018.

Canadian recommendations for training and performance in basic perioperative point-of-care ultrasound: recommendations from a consensus of Canadian anesthesiology academic centres.

Point-of-care ultrasound (POCUS) uses ultrasound at the bedside to aid decision-making in acute clinical scenarios. The increased use of ultrasound for regional anesthesia and vascular cannulation, together with more anesthesiologists trained in transesophageal echocardiography have contributed to the widespread use of POCUS in perioperative care. Despite the support of international experts, the practice of POCUS in perioperative care is variable as Canadian guidelines for anesthesiologists do not currently exist. Using a Delphi process of online surveys and a face-to-face national Canadian meeting, we developed a consensus statement for basic POCUS (bPOCUS) performance and training with a group of national experts from all Canadian universities. The group of experts consisted of 55 anesthesiologists from 12 Canadian universities considered local leaders in the field. An initial exploratory online survey of 47 statements was conducted. These statements were derived from previous generic guidelines or consensus conferences, or were based on current literature. Fourteen statements reached full consensus, 19 had 90-100% agreement, and 14 had less than 90% agreement. Eight new statements were proposed during the national meeting, and all statements without full agreement were discussed. A second online survey included 42 modified or new statements. From this second survey, 16 statements obtained full consensus, 39 had very good agreement, and one had good agreement. The final document includes 56 statements that define the scope of practice and necessary training for perioperative bPOCUS. The statements include five bPOCUS domains: cardiac, lung, airway, gastric, and abdomen. The use of bPOCUS is evolving and will play a significant role in perioperative medicine. This consensus statement aims to define a Canadian national standard on which curricula may be based. It also provides a framework to allow further development of bPOCUS in the perioperative setting.

RéSUMé: L'échographie ciblée (POCUS) utilise l'échographie au chevet des patients pour faciliter la prise de décisions dans les situations cliniques urgentes. L'utilisation accrue de l'échographie pour l'anesthésie régionale et la cannulation vasculaire, ainsi que l'augmentation du nombre d'anesthésologistes formés à l'échocardiographie transesophagienne, ont contribué à l'utilisation généralisée de l'échographie ciblée dans les soins périopératoires. Malgré son endossement par des experts internationaux, la pratique de l'échographie ciblée en soins périopératoires est variable, car il n'existe pas, à l'heure actuelle, de lignes directrices canadiennes destinées aux anesthésiologistes. À l'aide d'un processus Delphi de sondages en ligne et d'une réunion nationale canadienne en personne, un groupe d'experts nationaux provenant de toutes les universités canadiennes a élaboré une déclaration consensuelle pour la formation de base en et l'exécution de l'échographie ciblée (bPOCUS). Le groupe d'experts était composé de 55 anesthésiologistes issus de 12 universités canadiennes considérés comme des chefs de file locaux dans le domaine. Un premier sondage exploratoire en ligne comportant 47 énoncés a été réalisé. Ces énoncés étaient dérivés de lignes directrices antérieures ou de conférences consensuelles, ou étaient fondés sur la littérature actuelle. Quatorze énoncés ont obtenu un consensus complet, 19 ont atteint un taux de 90 à 100 %, et 14 ont obtenu moins de 90 % d'accord. Huit nouveaux énoncés ont été proposés au cours de la réunion nationale, et tous les énoncés n'ayant pas obtenu d'accord complet ont été discutés. Un deuxième sondage en ligne comprenait 42 énoncés modifiés ou nouveaux. Dans ce deuxième sondage, 16 énoncés ont obtenu un consensus total, 39 un très bon accord et un énoncé un bon accord. Le document final comporte 56 énoncés qui définissent le champ de pratique et la formation nécessaire pour l'échographie ciblée périopératoire de base. Les énoncés portent sur cinq domaines de l'échographie ciblée de base : échographie cardiaque, pulmonaire, des voies respiratoires, gastrique et abdominale. L'utilisation de l'échographie ciblée de base évolue et jouera un rôle important en médecine périopératoire. Cette déclaration consensuelle vise à définir une norme nationale canadienne sur laquelle les programmes d'études pourront s'appuyer. Elle fournit également un cadre pour encourager le développement ultérieur de l'échographie ciblée de base dans un contexte périopératoire.

A biased coin up-and-down sequential allocation trial to determine the optimum programmed intermittent epidural bolus time interval between 5 mL boluses of bupivacaine 0.125% with fentanyl 2 µg·mL-1.

PURPOSE: The optimal epidural mixtures and settings for programmed intermittent epidural bolus (PIEB) labour analgesia have yet to be determined. A previous study by our group demonstrated that 10 mL boluses of bupivacaine 0.0625% with fentanyl 2 µg·mL-1 administered every 40 min provided effective analgesia during the first stage of labour for 90% of women, without breakthrough pain. We wanted to determine the effective PIEB time interval of 5 mL boluses of bupivacaine 0.125% with fentanyl 2 µg·mL-1 under the same study circumstances, aiming at a future comparative study. METHODS: This double-blind dose-finding study used the biased coin up-and-down sequential allocation method to determine the effective PIEB interval 90% (EI90) needed to provide effective analgesia without breakthrough pain during the first stage of labour. We used fixed 5 mL boluses of bupivacaine 0.125% with fentanyl 2 µg.mL-1 and studied time intervals of 60, 50, 40, and 30 min. The first patient was assigned an interval of 60 min and the remaining intervals were assigned as per the biased coin up-and-down method. RESULTS: The estimated EI90 was 36.5 min (95% confidence interval [CI], 34.0 to 39.0) by the truncated Dixon and Mood method and 34.2 min (95% CI, 30.8 to 41.5) by the isotonic regression method. We found that 20/40 women had an upper sensory block to ice above T6, 34/40 women had no motor block, and no woman required treatment for hypotension. CONCLUSION: The EI90 between 5 mL boluses of bupivacaine 0.125% with fentanyl 2 µg·mL-1 during the first stage of labour is approximately 35 min. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT #02758405); registered 2 May, 2016.

Practice of Ultrasound-Guided Palpation of Neck Landmarks Improves Accuracy of External Palpation of the Cricothyroid Membrane.

BACKGROUND: Ultrasonography can accurately identify the cricothyroid membrane; however, its impact on the subsequent accuracy of external palpation is not known. In this study, we tested the ability of anesthesia participants to identify the midpoint of the cricothyroid membrane using external palpation with and without ultrasound (US)-guided practice. METHODS: Following institutional ethics approval and informed consent, anesthesia participants consisting of anesthesia residents, fellows, and practicing anesthesia assistants underwent didactic teaching on neck landmarks. The participants were then randomized to practice palpation of neck landmarks with US guidance (US group) or without ultrasonography (non-US [NUS] group). After the practice session, each participant identified the cricothyroid membrane using external palpation on the neck of 10 volunteers and marked the anticipated entry point for device insertion (palpation point [PT]). The midpoint of the cricothyroid membrane of each volunteer had been premarked with invisible ink using ultrasonography (US point) by a separate member of the research team. The primary outcome was the accuracy rate defined as the percentage of the attempts with the distance ≤5 mm measured from the PT to US point for the participant. The primary outcome was compared between NUS and US groups using Wilcoxon rank sum test. A mixed-effect logistic regression or mixed-effect linear model was also conducted for outcomes accounting for the clustering and adjusting for potential confounders. RESULTS: Fifteen anesthesia participants were randomized to US (n = 8) and NUS (n = 7) groups. A total of 80 and 61 attempts were performed by the US and NUS groups, respectively. The median accuracy rate in the US group was higher than the NUS group (65% vs 30%; P = .025), and the median PT-US distance in the US group was shorter than in the NUS group (4.0 vs 8.0 mm; P = .04). The adjusted mean PT-US distance in the US group was shorter compared to the NUS group (adjusted mean [95% CI], 3.6 [2.9-4.6] vs 6.8 [5.2-8.9] mm; P < .001). CONCLUSIONS: Anesthesia participants exposed to practice with US-guided palpation of the cricothyroid membrane location were better able to identify the cricothyroid membrane using only blind palpation than participants without US-guided practice. Practice with US-guided palpation of neck landmarks improves subsequent blind localization of the cricothyroid membrane using palpation alone.

Point-of-care gastric ultrasound and aspiration risk assessment: a narrative review.

This narrative review summarizes the current knowledge on point-of-care ultrasound (POCUS) of gastric contents in order to inform an assessment of aspiration risk and guide anesthetic management at the bedside. An I-AIM framework (Indication, Acquisition, Interpretation, and Medical decision-making) is used to summarize and organize the content areas. This narrative review spans the breadth of the literature on pediatric and adult subjects as well as on special patient populations such as obstetric and severely obese individuals. Areas that need further investigation include the diagnostic accuracy of gastric POCUS from a Bayesian perspective and the impact of POCUS on patient outcomes, healthcare economics, and educational curricula.