Residual gastric content after holding of glucagon-like peptide-1 receptor agonists before elective surgery: a cross-sectional study - The RESIDUAL study

Residual gastric content after holding of glucagon-like peptide-1 receptor agonists before elective surgery: a cross-sectional study - The RESIDUAL study

Citation: Boudreau C, Couture M, Rousseau-Saine N, Laferrière-Langlois P, Roy-Renaud É, Burey J, et al. Residual gastric content after holding of glucagon-like peptide-1 receptor agonists before elective surgery: a cross-sectional study - The RESIDUAL study. BMC Anesthesiol. 2026. doi:10.1186/s12871-026-03999-2 This episode asks whether fasted elective-surgery patients who held weekly injectable glucagon-like peptide-1 receptor agonists for at least 7 days still had more residual gastric content. Evidence is very uncertain whether use was associated with increased residual gastric content; aspiration outcomes were not collected. Study at a glance - Design and setting: Prospective cross-sectional study of fasted adults scheduled for elective surgery under anesthetic care at two university-affiliated hospitals in Montreal, Quebec, Canada, from October 2024 through February 2025; registered at ClinicalTrials.gov, NCT06500143. - Population: 94 patients undergoing elective procedures were included; 1 patient in the GLP-1 RA group was excluded after gastric ultrasound because the last dose was less than 7 days before surgery. 93 patients were analyzed: 52 in the GLP-1 RA group and 41 controls. Female sex was 40.9%. Inclusion required age at least 18 years, American Society of Anesthesiologists physical status I to IV, and fasting according to Canadian guidelines. In the exposure group, 50/52 (96%) received semaglutide, one patient received tirzepatide, one patient received dulaglutide, 45/52 (87%) had diabetes as the treatment indication, and median time since last dose was 11 days (IQR 9 to 13). - Exposure and comparator: Exposure was weekly injectable semaglutide, tirzepatide or dulaglutide use for more than 4 weeks, regardless of indication, with the last dose at least 7 days before surgery. The comparator group was not receiving any GLP-1 RA. Specific drug, dose in milligrams, and day of last injection were collected. - Primary outcome: Increased residual gastric content on preoperative gastric ultrasound after guideline-concordant fasting was defined as thick liquid, solid content, or more than 1.5 mL/kg clear liquid. It is very uncertain whether GLP-1 RA use was associated with increased residual gastric content: 22/52 (42.3) in the GLP-1 RA group versus 10/41 (24.4) in controls; unadjusted prevalence ratio 1.73, 95% CI 0.96 to 3.75; adjusted prevalence ratio 1.65, 95% CI 0.7 to 3.7; adjusted average treatment effect 15.4%, 95% CI -10 to 35.6; p-value not reported (very low certainty). - Key secondary outcome: Exploratory analyses were also very uncertain. For increased residual gastric content, the adjusted odds ratio per additional day since last GLP-1 RA injection was 1.08, 95% CI 0.86 to 1.39; per hour since last oral intake was 1.12, 95% CI 0.9 to 1.46; and per mg semaglutide dose was 2.19, 95% CI 0.47 to 12.7. p-values were not reported (very low certainty). - Confounding: The primary adjusted analysis used propensity-score overlap weighting for age, sex, American Society of Anesthesiologists physical status classification, BMI, diabetes, opioid use, moderate to severe preoperative pain (> 3 on the verbal rating scale), and time since last oral intake; balance threshold was 0.1 with no variables imbalanced. The planned augmented inverse probability weighting estimator was changed because of inadequate covariate balancing. Sensitivity analysis with augmented inverse probability weighting showed prevalence ratio 1.84, 95% CI 0.74 to 4.24, and average treatment effect 18.1%, 95% CI -10.2 to 38.7. Residual confounding by unmeasured diabetes-related factors remained a serious concern. - Risk of bias and certainty: ROBINS-I overall risk of bias was Serious, driven mainly by serious bias due to confounding. Selection of participants, exposure classification, deviations from intended exposure, and selection of reported result were Moderate; missing data and outcome measurement were Low. Overall GRADE certainty for increased residual gastric content was very low because of residual confounding, indirectness for clinical aspiration risk, and imprecision.

Prospective Evaluation of Routine Extubation Criteria in Children with Upper Respiratory Symptoms Undergoing Elective Surgery

Citation: Templeton TW, Smith LD, Mosher T, Saha AK, Hodges AS, Vishneski SR, et al. A Prospective Evaluation of Routine Extubation Criteria in Children with Upper Respiratory Symptoms Undergoing Elective Surgery. Anesthesiology. 2026. doi:10.1097/ALN.0000000000006197 This episode asks whether routine awake-extubation readiness criteria remain reassuring in children with upper respiratory infection symptoms undergoing elective surgery. The primary comparison is very uncertain: observed success was 94.7% without symptoms versus 93.9% with symptoms. Symptomatic children may have more desaturation, and unadjusted confounding limits causal conclusions. Study at a glance - Design and setting: Prospective observational cohort at a single center in the United States, conducted between November 20, 2019 and June 24, 2025, in elective outpatient or day-hospital pediatric surgery with planned general endotracheal anesthesia and awake extubation. Registered at ClinicalTrials.gov as NCT04155892 and prepared using Strengthening the Reporting of Observational Studies in Epidemiology guidelines. - Population: 927 subjects were screened; 799 were enrolled and extubated with one or more of the five extubation criteria; 756 patients were analyzed in the primary cohorts, including 379 in the non-upper respiratory infection symptom group and 377 in the upper respiratory infection symptom group. Inclusion criteria were children aged ≤9 years presenting for elective outpatient or day-hospital surgery with anticipated discharge on the day of surgery or postoperative day 1 and planned general endotracheal anesthesia; primary analysis required at least 3 of the Big Five extubation criteria. Female sex was 31.1%; age was 31.0 ± 26.4 months in the non-upper respiratory infection group and 37.9 ± 25.0 months in the upper respiratory infection group. - Exposure and comparator: Primary exposure was preoperative upper respiratory infection symptom status based on a parent or caregiver questionnaire: scores ≥3 defined the upper respiratory infection symptom group; scores 0 or 1 defined the non-upper respiratory infection reference group; score 2 was excluded as indeterminate. The questionnaire gave one point for each positive response plus a parent or caregiver sickness assessment scored 0 to 3; in the upper respiratory infection group, the median survey score was 4 (IQR 3 to 6). At emergence and extubation, an independent observer recorded the Big Five criteria: tidal volume >5 mL/kg, conjugate gaze, facial grimace, purposeful movement, and eye opening. - Primary outcome: Successful awake extubation at extubation occurred in 359/379 patients in the non-upper respiratory infection group, 94.7% (95% CI 92.5% to 97.0%), versus 354/377 patients in the upper respiratory infection group, 93.9% (95% CI 91.5% to 96.3%). Adjusted effect estimate not reported; unadjusted risk difference for non-upper respiratory infection versus upper respiratory infection was 0.8% (95% CI -2.6% to 4.2%); p-value not reported. The observed estimate fell within the study’s 5% clinical equivalence margin, but causal equivalence is very uncertain (very low certainty). - Key secondary outcome: At least one peri-extubation desaturation event occurred in 103/377 patients in the upper respiratory infection group, 27.3% (95% CI 22.8% to 31.8%), versus 62/379 in the non-upper respiratory infection group, 16.4% (95% CI 12.6% to 20.1%). Adjusted effect estimate not reported; unadjusted risk difference was 10.9% (95% CI 5.1% to 16.0%); p-value not reported, so upper respiratory infection symptoms may be associated with more desaturation (low certainty). Other secondary contrasts included visible endotracheal tube secretions, risk difference 43.3% (95% CI 37.1% to 49.5%, low certainty); major intervention, risk difference 1.0% (95% CI -1.1% to 3.2%, very low certainty); laryngospasm, risk difference 0.0% (95% CI -1.5% to 1.5%, very low certainty); postdischarge respiratory healthcare, risk difference 1.6% (95% CI -0.2% to 3.4%, very low certainty); and postanesthesia care unit oxygen saturation nadir, 96% (IQR 94 to 98) versus 95% (IQR 92 to 97), p-value <0.001 (very low certainty). - Confounding: No multivariable regression, propensity score, g-method, instrumental-variable, or other formal confounding adjustment was reported; group contrasts were unadjusted. Baseline prognostic factors differed between groups, including age, American Society of Anesthesiologists physical status, sleep-disordered breathing, and surgery type, and clinician experience was not accounted for. Clinicians were not blinded to questionnaire score, and albuterol administration differed as printed: 5/377 (1.3%) in the non-upper respiratory infection group versus 31/379 (8.2%) in the upper respiratory infection group, with printed denominators differing from final cohort sizes. - Risk of bias and certainty: ROBINS-E overall risk of bias was Serious. The main concern was serious confounding; moderate concerns included selection of participants, exposure classification, deviations from intended exposure, missing data, and selection of reported results, while outcome measurement was Low primarily for standardized observer-graded peri-extubation outcomes. Overall certainty was very low for successful awake extubation, low for peri-extubation desaturation and visible secretions, and very low for most other outcomes.

Environmental and economic impacts of anaesthesia: A simulation study comparing total intravenous anaesthesia versus sevoflurane for maintenance of anaesthesia in 11 909 adult patients of a Belgian tertiary hospital

Citation: Van Belleghem F, Rex S, Teunkens A, Vereecke H, Kalmar AF. Environmental and economic impacts of anaesthesia: A simulation study comparing total intravenous anaesthesia versus sevoflurane for maintenance of anaesthesia in 11 909 adult patients of a Belgian tertiary hospital. Eur J Anaesthesiol. 2026;43:567-574. doi:10.1097/EJA.0000000000002342 This study simulated total intravenous anaesthesia versus sevoflurane for maintenance and compared carbon dioxide equivalent emissions and costs. Low-certainty evidence suggests total intravenous anaesthesia has much lower emissions; cost savings are very uncertain. Internal numerical discrepancies and no uncertainty analysis limit exact estimates. Study at a glance - Design and setting: Retrospective simulation-based observational cohort study using electronic records from a single Belgian hospital, Sint-Jan Hospital, Bruges, Belgium. Anaesthesia time was defined as start of induction to end of surgery; results were standardised per 1000 procedures. - Population: 11909 cases were analysed. Inclusion criteria were all general anaesthesia procedures lasting more than 10 min in patients older than 5 years from 1 April to 30 November 2022. Baseline characteristics: 49.9% female, 50.1% male, mean age 55 ± 21 years, anaesthesia time 92 ± 73 min, height 169 ± 12 cm, weight 77 ± 20 kg. - Exposure and comparator: Each procedure was simulated under four maintenance scenarios with FiO2 50%: sevoflurane with minimal fresh gas flow using automatic gas control with a Flow-I ventilator; sevoflurane with 2 l min-1 fresh gas flow; total intravenous anaesthesia using 1% propofol vials and 6 l fresh gas flow; and total intravenous anaesthesia using 2% propofol vials and 6 l fresh gas flow. All scenarios used induction with propofol 2 mg kg-1 and maintenance with either volatile anaesthetic or propofol 6 mg kg-1 h-1. - Primary outcome: CO2-equivalent emissions per 1000 procedures: 25593 kg for minimal-flow sevoflurane, 59489 kg for sevoflurane 2 l min-1 fresh gas flow, 1271 kg for total intravenous anaesthesia with 1% propofol, and 812 kg for total intravenous anaesthesia with 2% propofol. The article reported minimal-flow sevoflurane as 26.5 times more CO2e than total intravenous anaesthesia and sevoflurane 2 l min-1 fresh gas flow as 61.8 times more; this suggests lower emissions with total intravenous anaesthesia. No adjusted effect estimate, 95% CI, or p-value reported (low certainty). - Key secondary outcome: Economic cost per 1000 procedures: €6805 for minimal-flow sevoflurane, €11961 for sevoflurane 2 l min-1 fresh gas flow, €5666 for total intravenous anaesthesia with 1% propofol, and €4264 for total intravenous anaesthesia with 2% propofol. The article reported total intravenous anaesthesia as 16.7 to 52.63% less expensive than sevoflurane, and as costing 36% and 63% of sevoflurane anaesthesia costs with minimal flow and 2 l min-1 fresh gas flow, respectively; exact cost savings are very uncertain. No adjusted effect estimate, 95% CI, or p-value reported (very low certainty). - Confounding: Patient-level confounding by indication was partly avoided because the same 11909 recorded cases were simulated under each anaesthesia scenario. No causal DAG, covariate-adjusted analysis, propensity score diagnostics, formal validation, or sensitivity analysis was reported; residual concerns depend on fixed assumptions for dosing, fresh gas flow, equipment, vial use, resource use, lifecycle emissions, and local prices. - Risk of bias and certainty: Overall ROBINS-I risk of bias was Serious. Key concerns were serious bias in selection of the reported result, moderate concerns for confounding, exposure classification, deviations from intended interventions, and outcome measurement, no information for missing data, and low concern for participant selection. Overall GRADE certainty for the primary CO2-equivalent emissions outcome was low; cost outcomes were very low certainty.

An interpretable machine learning model for predicting emergence agitation in children: a multicenter development and validation study

Citation: Zhao Q, Zhang Y, An R, Yi B, Huang G. An interpretable machine learning model for predicting emergence agitation in children: a multicenter development and validation study. BMC Anesthesiol. 2026;[epub ahead of print]. This multicenter retrospective study from two Chinese hospitals developed and externally validated several machine learning models to predict emergence agitation in children after general anesthesia. Using five routine perioperative predictors, a compact multilayer perceptron model showed excellent discrimination internally but only moderate performance and suboptimal calibration in an external cohort. Because variable selection, model choice, and key predictors are highly data- and center-dependent, the tool is best seen as a proof-of-concept rather than a ready-made decision aid for routine paediatric anesthesia practice. Study at a glance - Design and setting: Retrospective multicenter prediction-model study using electronic records from two tertiary hospitals in China: Center I (Third Affiliated Hospital of Zunyi Medical University) for model development and internal validation, and Center II (First Affiliated Hospital of Army Medical University) as an independent external validation cohort. Children aged 3–12 years with American Society of Anesthesiologists physical status I–II undergoing elective surgery under general anesthesia were included. - Participants and primary outcome: A total of 445 pediatric patients were analyzed (321 in the development center, 124 in the external validation center). In Center I, emergence agitation occurred in 95 children, an incidence of 29.6%; in Center II, the reported incidence was about 25.8% (32–33 events, with slight inconsistencies across sections). The primary outcome was emergence agitation within 30 minutes after post-anesthesia care unit admission, defined as Pediatric Anesthesia Emergence Delirium (PAED) score >10, after pain was assessed and treated using the FLACC scale to limit misclassification from pain-related distress. - Predictors and main model: From 63 perioperative variables, the authors used univariable screening followed by least absolute shrinkage and selection operator (LASSO) regression to select predictors, then trained six algorithms (logistic regression, support vector machine, multilayer perceptron, random forest, extreme gradient boosting, and Light Gradient Boosting Machine). The final five-variable clinical model used parental educational level, preoperative alanine aminotransferase (ALT), postoperative patient-controlled analgesia (PCA) pump use, postoperative antagonist (reversal agent) use, and extubation suctioning frequency. A multilayer perceptron (MLP) was chosen as the primary clinical model because it performed best in external validation; a support vector machine was used for detailed interpretability analyses with SHAP values. - Key performance results: In internal holdout validation at Center I, discrimination was high across models, with area under the receiver operating curve (AUC) around 0.87–0.92; the support vector machine achieved AUC 0.918 (95% confidence interval 0.844–0.973, Brier score 0.098), and logistic regression AUC 0.915. In external validation at Center II, performance dropped noticeably. The primary clinical MLP model achieved AUC 0.705 (95% confidence interval 0.59–0.804) with a Brier score of 0.190, reflecting only moderate discrimination and imperfect calibration; other models performed worse (e.g., logistic regression AUC 0.587, LightGBM AUC 0.494). No decision-curve or net benefit analyses were reported. - Risk of bias and applicability: Using a structured prediction-model appraisal, overall risk of bias was judged high, mainly due to the analysis domain. Concerns include data-driven predictor selection from many candidates, testing and informally selecting among six algorithms, limited optimism correction (formally reported only for the support vector machine), and a relatively small, case-mix–different external validation cohort. Applicability is further constrained because three of the five final predictors (PCA pump use, antagonist use, suctioning frequency) are early postoperative management decisions that vary by center and over time, rather than stable baseline risk factors. - Practice implications: For practising clinicians, this study underscores that emergence agitation after pediatric anesthesia is common and potentially predictable, and it highlights perioperative features—such as parental education, preoperative ALT, and postoperative analgesia and reversal strategies—that may correlate with risk. However, the current models should not be used as stand-alone decision aids: external performance is only moderate, calibration is imperfect, and the models depend strongly on center-specific management choices. At present, these tools are best viewed as research prototypes and a stimulus for locally developed and rigorously validated prediction models, rather than as ready-to-implement clinical calculators.

Clinical Performance in Critical Care Simulation Under Sleep Deprivation: Effects of Power Napping in the R-NAP Randomized Controlled Trial

Citation: Schmidt L, Genty F, Delaire T, Valero B, Rey I, Galan L, Mairet-Mabboux S, Douplat M, Schlatter S, Rimmele T, Mazza S, Lilot M. Clinical Performance in Critical Care Simulation Under Sleep Deprivation: Effects of Power Napping in the R-NAP Randomized Controlled Trial. Anesthesiology. 2026; doi:10.1097/ALN.0000000000006135. In this single-centre randomized controlled trial, anesthesia and intensive care residents finishing an overnight on-site shift were assigned either to a brief supervised nap opportunity or to quiet wakefulness before a high-fidelity critical care simulation. The nap group achieved higher overall and non-technical performance scores without reported harms, but the trial is small, uses simulation rather than real patient outcomes, and has some missing data, so confidence in the size of benefit is moderate and the findings mainly support, rather than replace, broader fatigue management strategies. Study at a glance - Design and setting: Prospective individually randomized parallel-group behavioural trial conducted in a single French university simulation centre, comparing a supervised thirty-minute nap opportunity versus quiet wakefulness after an overnight on-site shift in anesthesia and intensive care residents. - Participants: Thirty-five second to fifth year anesthesia and intensive care residents were randomized (nineteen to nap, sixteen to no nap); twenty-seven with complete actigraphy sleep data were included in the primary adjusted analysis, with similar baseline characteristics between groups. - Primary outcome: Overall simulated clinical performance (sum of technical and non-technical scores, range zero to two hundred) after the overnight shift was higher with a nap; the adjusted mean difference was 14.84 points in favour of the nap group, with a ninety-five percent confidence interval from 2.8 to 26.88 and a P value of 0.018, yielding moderate certainty that a brief nap improves overall simulated performance. - Key secondary outcomes: Total non-technical skills score (zero to one hundred) was higher with a nap, with an adjusted mean difference of 11.03 points (ninety-five percent confidence interval 2.22 to 19.84; P value 0.016). Among Ottawa Global Rating Scale subscales, Overall performance (mean difference 0.77; ninety-five percent confidence interval 0.05 to 1.48; P value 0.036), Leadership (0.73; ninety-five percent confidence interval 0.05 to 1.41; P value 0.037), and Resource utilization (1.02; ninety-five percent confidence interval 0.03 to 2.00; P value 0.043) favoured the nap group, whereas purely technical checklist scores showed smaller, imprecise differences. - Harms and safety: No intervention-related adverse events or harms were reported in either the nap group (zero of nineteen) or the control group (zero of sixteen) during or after the brief nap or quiet wakefulness periods. - Risk of bias and certainty: Overall risk of bias was judged as having some concerns, mainly due to missing outcome data (eight of thirty-five randomized residents excluded from the primary model because of missing actigraphy) and lack of participant blinding, although assessors were blinded and outcomes were structured and video-based. Using this and the reasonably precise effect estimate, certainty in the primary outcome was rated as Moderate. - Applicability and limitations: Findings apply most directly to anesthesia and intensive care residents in similar academic settings and to high-fidelity simulation; they are indirect for attending physicians, other specialties, or real-world patient outcomes. The trial is small and single-centre, with multiple secondary and exploratory analyses without adjustment for multiplicity, so apparent benefits on individual subscales should be interpreted cautiously and used to support, not replace, broader fatigue risk management policies.