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.

Baseline Gastric Volume in Fasting Diabetic Patients Is Not Higher than That in Nondiabetic Patients: A Cross-sectional Noninferiority Study.

BACKGROUND: The physiology of diabetes mellitus can increase the risk of perioperative aspiration, but there is limited and contradictory evidence on the incidence of "full stomach" in fasting diabetic patients. The aim of this study is to assess the baseline gastric content (using gastric ultrasound) in diabetic and nondiabetic patients scheduled for elective surgery who have followed standard preoperative fasting instructions. METHODS: This was a prospective, noninferiority study of 180 patients (84 diabetic and 96 nondiabetic patients). Bedside ultrasound was used for qualitative and quantitative assessment of the gastric antrum in the supine and right lateral decubitus positions. Fasting gastric volume was estimated based on the cross-sectional area of the gastric antrum and a validated model. The hypothesis was that diabetic patients would not have a higher baseline fasting gastric volume compared to nondiabetic patients, with a noninferiority margin of 0.4 ml/kg. Secondary aims included the comparison of the incidence of full stomach (solid content or more than 1.5 mL/kg of clear fluid), estimation of the 95th percentile of the gastric volume distribution in both groups, and examination of the association between gastric volume, glycemic control, and diabetic comorbidities. RESULTS: The baseline gastric volume was not higher in diabetic patients (0.81 ± 0.61 ml/kg) compared to nondiabetic patients (0.87 ± 0.53 ml/kg) with a mean difference of -0.07 ml/kg (95% CI, -0.24 to 0.10 ml/kg). A total of 13 (15.5%) diabetic and 11 (11.5%) nondiabetic patients presented more than 1.5 ml/kg of gastric volume (95% CI for difference, -7.1 to 15.2%). There was little correlation between the gastric volume and either the time since diagnosis or HbA1C. CONCLUSIONS: The data suggest that the baseline gastric volume in diabetic patients who have followed standard fasting instructions is not higher than that in nondiabetic patients.

Impact of Sugammadex Versus Neostigmine Reversal on Postoperative Recovery Time in Patients With Obstructive Sleep Apnea Undergoing Bariatric Surgery: A Double-Blind, Randomized Controlled Trial.

BACKGROUND: Residual neuromuscular blockade can be associated with serious postoperative complications. Sugammadex is a newer neuromuscular blocking drug (NMBD) reversal agent that rapidly and completely reverses rocuronium. Whether sugammadex has any advantages over neostigmine in morbidly obese patients with obstructive sleep apnea (OSA) is unclear. We investigated whether sugammadex would reduce discharge time from the operating room (OR) compared with neostigmine in morbidly obese patients with OSA undergoing bariatric surgery. METHODS: This was a prospective, double-blinded randomized controlled superiority trial with 2 parallel groups. Patients were randomized 1:1 into reversal of NMBD with sugammadex or neostigmine. Our inclusion criteria were morbidly obese adult patients with OSA undergoing elective bariatric surgery under general anesthesia. Our exclusion criteria were allergy to rocuronium, sugammadex or neostigmine, malignant hyperthermia, hepatic or renal insufficiency, neuromuscular diseases, and an inability to give consent. The primary outcome was the time from administration of the NMBD reversal agent to discharge from the OR. Secondary outcomes included the time from administration of the NMBD reversal agent to the time the patient opened eyes to command, and the time to extubation. The Mann-Whitney test was used to compare the outcomes between treatment groups. RESULTS: We randomized 120 patients into 2 groups of 60 patients. Overall median body mass index (BMI) was 48.1 kg/m2 ([interquartile range, IQR]) [43.0-53.5]. The time from drug administration to discharge from OR was 13.0 minutes [10.0-17.0] in the sugammadex group and 13.5 minutes [11.0-18.3] in the neostigmine group (P = .27). The treatment effect estimate with a bootstrapped 95% confidence interval [CI] for time from admission to discharge from OR was -0.5 [-2.5 to 3]. No differences were observed in postoperative complications and other secondary outcomes. CONCLUSIONS: No difference was observed in OR discharge time in morbidly obese patients with OSA when sugammadex was administered instead of neostigmine.

A hood shield reduces postdoffing contamination during simulated COVID-19 airway management: an exploratory, simulation-based randomized study.

PURPOSE: SARS-CoV-2 poses a significant occupational health threat to health care workers performing aerosol-generating medical procedures, with a threefold increased risk of a positive test and predicted infection compared with the general population. Nevertheless, the personal protective equipment (PPE) configuration that provides better protection with lower contamination rates is still unknown. METHODS: We enrolled 40 practitioners with airway management training (anesthesiologists, anesthesia assistants/nurses) in an exploratory, simulation-based randomized study. We evaluated the performance of a novel, locally designed hood (n = 20) in terms of protection from surrogate contamination using an ultraviolet (UV) marker during a standardized urgent intubation procedure and a simulated episode of coughing in a high-fidelity simulation setting compared with standard PPE (n = 20). The primary outcome was the presence of residual UV fluorescent contamination on any base clothing or exposed skin of the upper body after doffing PPE assessed by a blinded evaluator. RESULTS: The proportion of participants with residual contamination on any base clothing or exposed skin of the upper body after doffing was less than half in the hood PPE group compared with the standard PPE group (8/20 [40%] vs 18/20 [90%], respectively; P = 0.002). CONCLUSIONS: Compared with standard PPE, enhanced PPE with a locally designed prototype hood was associated with reduced contamination of the upper torso and fewer body areas being exposed to droplets after a simulated aerosol-generating scenario without designed airflow. STUDY REGISTRATION: ClinicalTrials.gov (NCT04373096); registered 4 May 2020.

RéSUMé: OBJECTIF: Le SRAS-CoV-2 représente une menace importante pour la santé au travail des travailleurs de la santé réalisant des interventions médicales générant des aérosols, avec un risque trois fois plus élevé de test positif au SRAS-CoV-2 et d'infection prédite au SRAS-CoV-2 par rapport à la population générale. Néanmoins, la configuration optimale des équipements de protection individuelle (EPI) offrant la meilleure protection avec des taux de contamination plus faibles est encore inconnue. MéTHODE: Nous avons recruté 40 praticiens ayant une formation en prise en charge des voies aériennes (anesthésiologistes, assistants en anesthésie/personnel infirmier) dans le cadre d'une étude exploratoire randomisée de simulation. Nous avons évalué la performance d'un nouveau capuchon conçu localement (n = 20) par rapport aux EPI standards (n = 20) en termes de protection contre la contamination de substitution à l'aide d'un marqueur ultraviolet (UV) au cours d'une procédure d'intubation urgente normalisée et d'un épisode simulé de toux dans un environnement de simulation haute fidélité. Le critère d'évaluation principal était la présence d'une contamination résiduelle par fluorescence UV sur les vêtements de base ou la peau exposée du haut du corps après le retrait des EPI telle qu'évaluée par un évaluateur en aveugle. RéSULTATS: La proportion de participants présentant une contamination résiduelle sur les vêtements de base ou la peau exposée du haut du corps après le retrait des équipements de protection était de moins de la moitié dans le groupe ayant porté le capuchon par rapport au groupe EPI standard (8/20 [40 %] vs 18/20 [90 %], respectivement; P = 0,002). CONCLUSION: Par rapport aux EPI standards, les EPI améliorés avec un prototype de capuchon conçu localement étaient associés à une contamination réduite du haut du torse et à moins de zones du corps exposées aux gouttelettes après une mise en situation simulée de génération d'aérosols sans flux d'air préconçu. ENREGISTREMENT DE L'éTUDE: clinicaltrials.gov (NCT04373096); enregistrée le 4 mai 2020.

No Benefits of Adding Dexmedetomidine, Ketamine, Dexamethasone, and Nerve Blocks to an Established Multimodal Analgesic Regimen after Total Knee Arthroplasty.

BACKGROUND: An optimal opioid-sparing multimodal analgesic regimen to treat severe pain can enhance recovery after total knee arthroplasty. The hypothesis was that adding five recently described intravenous and regional interventions to multimodal analgesic regimen can further reduce opioid consumption. METHODS: In a double-blinded fashion, 78 patients undergoing elective total knee arthroplasty were randomized to either (1) a control group (n = 39) that received spinal anesthesia with intrathecal morphine, periarticular local anesthesia infiltration, intravenous dexamethasone, and a single injection adductor canal block or (2) a study group (n = 39) that received the same set of analgesic treatments plus five additional interventions: local anesthetic infiltration between the popliteal artery and capsule of the posterior knee, intraoperative intravenous dexmedetomidine and ketamine, and postoperatively, one additional intravenous dexamethasone bolus and two additional adductor canal block injections. The primary outcome measure was 24-h cumulative opioid consumption after surgery and secondary outcomes were other analgesics, patient recovery, functional outcomes, and adverse events. RESULTS: Opioid consumption was not different between groups at 24 h (oral morphine equivalents, mean ± SD; study: 23.7 ± 18.0 mg vs. control: 29.3 ± 18.7 mg; mean difference [95% CI], -5.6 mg [-2.7 to 13.9]; P = 0.189) and all other time points after surgery. There were no major differences in pain scores, quality of recovery, or time to reach rehabilitation milestones. Hypotensive episodes occurred more frequently in the study group (25 of 39 [64.1%] vs. 13 of 39 [33.3%]; P = 0.010). CONCLUSIONS: In the presence of periarticular local anesthesia infiltration, intrathecal morphine, single-shot adductor canal block and dexamethasone, the addition of five analgesic interventions-local anesthetic infiltration between the popliteal artery and capsule of the posterior knee, intravenous dexmedetomidine, intravenous ketamine, an additional intravenous dexamethasone dose, and repeated adductor canal block injections-failed to further reduce opioid consumption or pain scores or to improve functional outcomes after total knee arthroplasty.

Diagnostic Point-of-Care Ultrasound: Recommendations From an Expert Panel.

Diagnostic point-of-care ultrasound (PoCUS) has emerged as a powerful tool to help anesthesiologists guide patient care in both the perioperative setting and the subspecialty arenas. Although anesthesiologists can turn to guideline statements pertaining to other aspects of ultrasound use, to date there remains little in the way of published guidance regarding diagnostic PoCUS. To this end, in 2018, the American Society of Anesthesiologists chartered an ad hoc committee consisting of 23 American Society of Anesthesiologists members to provide recommendations on this topic. The ad hoc committee convened and developed a committee work product. This work product was updated in 2021 by an expert panel of the ad hoc committee to produce the document presented herein. The document, which represents the consensus opinion of a group of practicing anesthesiologists with established expertise in diagnostic ultrasound, addresses the following issues: (1) affirms the practice of diagnostic PoCUS by adequately trained anesthesiologists, (2) identifies the scope of practice of diagnostic PoCUS relevant to anesthesiologists, (3) suggests the minimum level of training needed to achieve competence, (4) provides recommendations for how diagnostic PoCUS can be used safely and ethically, and (5) provides broad guidance about diagnostic ultrasound billing.

Gastric content and perioperative pulmonary aspiration in patients with diabetes mellitus: a scoping review.

BACKGROUND: Gastric emptying may be delayed in patients with diabetes mellitus (DM). However, the incidence of full stomach in fasting patients with DM and their risk of pulmonary aspiration under anaesthesia is not well understood. METHODS: A scoping review was undertaken to map the literature on aspiration risk in DM. A search was conducted in seven bibliographic databases, including MEDLINE and Embase, for original articles that studied aspiration risk, gastric emptying, or gastric content and volume. Selection and characterisation were performed by two independent reviewers using a predefined protocol registered externally. RESULTS: The search identified 5063 unique records, and 16 studies (totalling 775 patients with DM) were selected: nine studied gastric emptying and seven studied gastric content or volume. There were no studies reporting the incidence of aspiration in subjects with DM. All nine studies reported delayed emptying in patients with DM compared with healthy controls. Amongst the seven studies that compared gastric residual content/volume (GRV) in the perioperative period, five reported clinically negligible GRV in both patients with DM and controls, whereas two observed a higher incidence of 'full' stomach in patients with DM. CONCLUSIONS: The evidence concerning the aspiration risk for surgical patients with DM is based on a limited number of studies, mostly unblinded, reporting physiological data on gastric emptying and gastric volume as surrogate markers of aspiration risk. Data on fasting gastric content and volume in patients with DM are limited and contradictory; hence, the true risk of aspiration in fasting patients with DM is unknown.

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.

Ultrasound assessment of gastric volumes of thick fluids: Validating a prediction model.

BACKGROUND: Enteral nutrition is essential in the treatment of critically ill patients. Current methods to monitor enteral nutrition such as aspiration of residual volume may be inaccurate. Gastric ultrasonography estimates total gastric fluid volume using the Perlas model, but this model is validated for clear fluids only, and its accuracy for measuring thick fluids is unknown. OBJECTIVES: The primary aim of this study was to evaluate the Perlas model for gastric volume estimation of enteral nutrition, a thick fluid product. DESIGN: A single-centre, single blinded, randomised controlled study. SETTING: Single university hospital, from May to July 2019. PARTICIPANTS: Seventy-two healthy fasted volunteers were randomly allocated to different fluid volume groups. INTERVENTION: Participants randomly ingested predetermined volumes between 50 and 400 ml of a feeding-drink (Nutricia Nutridrink). Following a standardised gastric ultrasound scanning protocol, a blinded sonographer measured the antral cross-sectional area in the supine and right-lateral decubitus positions. MAIN OUTCOME MEASURES: Measurements were performed at baseline, 5 min postingestion and 20 min postingestion. Gastric volumes were predicted using the previously established Perlas model and compared with total gastric fluid volumes after ingestion of the study drink. RESULTS: The Perlas model underestimated the volume of thick gastric fluid and yielded a suboptimal fit for our data. However, antral cross-sectional area and total gastric thick fluid volumes were significantly correlated (Pearson's correlation coefficient 0.73, P < 0.01). A new model was fitted to predict gastric volumes of thick fluids, using the antral cross-sectional area (cm2) in the right-lateral decubitus position: Volume (ml) = 79.38 + 13.32 x right-lateral cross-sectional area. CONCLUSION: The Perlas model for clear gastric fluid volume estimation is suboptimal for thick fluid volume assessment and an alternative model is presented. CLINICAL TRIAL REGISTRATION: Netherlands Trial Register Trial NL7677, Registration date: 16 April 2019; https://www.trialregister.nl/trial/7677.

Intrathecal Morphine and Pulmonary Complications after Arthroplasty in Patients with Obstructive Sleep Apnea: A Retrospective Cohort Study.

BACKGROUND: Intrathecal morphine is commonly and effectively used for analgesia after joint arthroplasty, but has been associated with delayed respiratory depression. Patients with obstructive sleep apnea may be at higher risk of postoperative pulmonary complications. However, data is limited regarding the safety of intrathecal morphine in this population undergoing arthroplasty. METHODS: This retrospective cohort study aimed to determine the safety of intrathecal morphine in 1,326 patients with documented or suspected obstructive sleep apnea undergoing hip or knee arthroplasty. Chart review was performed to determine clinical characteristics, perioperative events, and postoperative outcomes. All patients received neuraxial anesthesia with low-dose (100 µg) intrathecal morphine (exposure) or without opioids (control). The primary outcome was any postoperative pulmonary complication including: (1) respiratory depression requiring naloxone; (2) pneumonia; (3) acute respiratory event requiring consultation with the critical care response team; (4) respiratory failure requiring intubation/mechanical ventilation; (5) unplanned admission to the intensive care unit for respiratory support; and (6) death from a respiratory cause. The authors hypothesized that intrathecal morphine would be associated with increased postoperative complications. RESULTS: In 1,326 patients, 1,042 (78.6%) received intrathecal morphine. The mean age of patients was 65 ± 9 yr and body mass index was 34.7 ± 7.0 kg/m. Of 1,326 patients, 622 (46.9%) had suspected obstructive sleep apnea (Snoring, Tired, Observed, Pressure, Body Mass Index, Age, Neck size, Gender [STOP-Bang] score greater than 3), while 704 of 1,326 (53.1%) had documented polysomnographic diagnosis. Postoperatively, 20 of 1,322 (1.5%) patients experienced pulmonary complications, including 14 of 1,039 (1.3%) in the exposed and 6 of 283 (2.1%) in the control group (P = 0.345). Overall, there were 6 of 1 322 (0.5%) cases of respiratory depression, 18 of 1,322 (1.4%) respiratory events requiring critical care team consultation, and 4 of 1,322 (0.3%) unplanned intensive care unit admissions; these rates were similar between both groups. After adjustment for confounding, intrathecal morphine was not significantly associated with postoperative pulmonary complication (adjusted odds ratio, 0.60 [95% CI, 0.24 to 1.67]; P = 0.308). CONCLUSIONS: Low-dose intrathecal morphine, in conjunction with multimodal analgesia, was not reliably associated with postoperative pulmonary complications in patients with obstructive sleep apnea undergoing joint arthroplasty.

High-flow nasal oxygen does not increase the volume of gastric secretions during spontaneous ventilation.

BACKGROUND: High-flow, heated, and humidified nasal oxygen therapy (HFNO) is frequently used in critical care and perioperative settings for a range of clinical applications. Much of the benefit of HFNO is attributed to generation of modest levels of positive airway pressure. Concern has been raised that this positive airway pressure may cause gastric insufflation, potentially increasing the risk of regurgitation and aspiration in an unprotected airway. METHODS: A prospective, interventional, assessor-blinded study was undertaken to evaluate the effects of HFNO on gastric content and gastric distension in healthy fasted adult volunteers assessed by ultrasonography. The primary outcome was the volume of gastric secretions. The secondary outcomes were the incidence of gastric air insufflation and the distribution of gastric antral grades. RESULTS: Sixty subjects were enrolled. No subject was found to have air gastric distension either at baseline or after treatment with HFNO. All subjects had either a Grade 0 or Grade 1 antrum, with similar distribution of antral grades and similar volume of gastric secretions before and after treatment with HFNO. CONCLUSIONS: There was no evidence that treatment with HFNO at flow rates of up to 70 L min-1 for 30 min resulted in gastric distension or an increase in gastric secretions in healthy individuals breathing spontaneously. The generalisability of these findings to subjects under anaesthesia and patients with incompetence of the lower oesophageal sphincter or impaired gastric emptying requires further investigation. CLINICAL TRIAL REGISTRATION: NCT03134937.

Diagnostic Accuracy of Point-of-Care Gastric Ultrasound.

BACKGROUND: Pulmonary aspiration of gastric contents is associated with significant perioperative morbidity and mortality. Previous studies have investigated the validity, reliability, and possible clinical impact of gastric ultrasound for the assessment of gastric content at the bedside. In the present study, we examined the accuracy (evaluated as sensitivity, specificity, and likelihood ratios) of point-of-care gastric ultrasound to detect a "full stomach" in a simulated scenario of clinical equipoise. METHODS: After a minimum fasting period of 8 hours, 40 healthy volunteers were randomized in a 1:1 ratio to either remain fasted or ingest a standardized quantity of clear fluid or solid. Each subject was randomized twice on 2 independent study sessions at least 24 hours apart. A gastric ultrasound examination was performed by a blinded sonographer following a standardized scanning protocol. Using a combination of qualitative and quantitative findings, the result was summarized in a dichotomous manner as positive (any solid or >1.5 mL/kg of clear fluid) or negative (no solid and ≤1.5 mL/kg of clear fluid) for full stomach. RESULTS: Data from 80 study sessions were analyzed. In this simulated clinical scenario with a pretest probability of 50%, point-of-care gastric ultrasound had a sensitivity of 1.0 (95% confidence interval [CI], 0.925-1.0), a specificity of 0.975 (95% CI, 0.95-1.0), a positive likelihood ratio of 40.0 (95% CI, 10.33-∞), a negative likelihood ratio of 0 (95% CI, 0-0.072), a positive predictive value of 0.976 (95% CI, 0.878-1.0), and a negative predictive value of 1.0 (95% CI, 0.92-1.0). CONCLUSIONS: Our results suggest that bedside gastric ultrasound is highly sensitive and specific to detect or rule out a full stomach in clinical scenarios in which the presence of gastric content is uncertain.

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.

Informed consent for regional anesthesia.

PURPOSE OF REVIEW: This narrative review describes the current framework for informed consent discussions for regional anesthesia practice from an ethical and medicolegal stand point as the cornerstone of the patient-physician relationship and the respect for patient autonomy. Recent guidelines and position statements from anesthesia societies have emphasized the importance of these discussions and their appropriate documentation. RECENT FINDINGS: Recent studies have shown that patients want to know more about both common and benign, as well as rare but serious adverse events, as it relates to their anesthetic care. Several strategies have been recently recommended as a means to facilitate a meaningful consent discussion and proper documentation in the perioperative environment. SUMMARY: Defining the material risks of ultrasound-guided regional anesthetic procedures remains challenging, due in part to the difficulty in quantifying incidence rates of relatively rare events. However, well informed discussions are of great importance to support patient autonomy and lay a strong foundation for the patient-anesthesiologist relationship.

Anesthesia Technique and Mortality after Total Hip or Knee Arthroplasty: A Retrospective, Propensity Score-matched Cohort Study.

BACKGROUND: This propensity score-matched cohort study evaluates the effect of anesthetic technique on a 30-day mortality after total hip or knee arthroplasty. METHODS: All patients who had hip or knee arthroplasty between January 1, 2003, and December 31, 2014, were evaluated. The principal exposure was spinal versus general anesthesia. The primary outcome was 30-day mortality. Secondary outcomes were (1) perioperative myocardial infarction; (2) a composite of major adverse cardiac events that includes cardiac arrest, myocardial infarction, or newly diagnosed arrhythmia; (3) pulmonary embolism; (4) major blood loss; (5) hospital length of stay; and (6) operating room procedure time. A propensity score-matched-pair analysis was performed using a nonparsimonious logistic regression model of regional anesthetic use. RESULTS: We identified 10,868 patients, of whom 8,553 had spinal anesthesia and 2,315 had general anesthesia. Ninety-two percent (n = 2,135) of the patients who had general anesthesia were matched to similar patients who did not have general anesthesia. In the matched cohort, the 30-day mortality rate was 0.19% (n = 4) in the spinal anesthesia group and 0.8% (n = 17) in the general anesthesia group (risk ratio, 0.42; 95% CI, 0.21 to 0.83; P = 0.0045). Spinal anesthesia was also associated with a shorter hospital length of stay (5.7 vs. 6.6 days; P < 0.001). CONCLUSIONS: The results of this observational, propensity score-matched cohort study suggest a strong association between spinal anesthesia and lower 30-day mortality, as well as a shorter hospital length of stay, after elective joint replacement surgery.

An Expedited Care Pathway with Ambulatory Brachial Plexus Analgesia Is a Cost-effective Alternative to Standard Inpatient Care after Complex Arthroscopic Elbow Surgery: A Randomized, Single-blinded Study.

BACKGROUND: Common standard practice after complex arthroscopic elbow surgery includes hospital admission for 72 h. The authors hypothesized that an expedited care pathway, with 24 h of hospital admission and ambulatory brachial plexus analgesia and continuous passive motion at home, results in equivalent elbow range of motion (ROM) 2 weeks after surgery compared with standard 72-h hospital admission. METHODS: A randomized, single-blinded study was conducted after obtaining approval from the research ethics board. Forty patients were randomized in a 1:1 ratio using a computer-generated list of random numbers into an expedited care pathway group (24-h admission) and a control group (72-h admission). They were treated equally aside from the predetermined hospital length of stay. RESULTS: Patients in the control (n = 19) and expedited care pathway (n = 19) groups achieved similar elbow ROM 2 weeks (119 ± 18 degrees and 121 ± 15 degrees, P = 0.627) and 3 months (130 ± 18 vs. 130 ± 11 degrees, P = 0.897) postoperatively. The mean difference in elbow ROM at 2 weeks was 2.6 degrees (95% CI, -8.3 to 13.5). There were no differences in analgesic outcomes, physical function scores, and patient satisfaction up to 3 months postoperatively. Total hospital cost of care was 15% lower in the expedited care pathway group. CONCLUSION: The results suggest that an expedited care pathway with early hospital discharge followed by ambulatory brachial plexus analgesia and continuous passive motion at home is a cost-effective alternative to 72 h of hospital admission after complex arthroscopic elbow surgery.