This Week in Anesthesiology — Sep 14, 2026

Welcome to This Week in Anesthesiology. This week we're covering 10 notable papers spanning intraoperative monitoring and haemodynamic management, airway safety and aspiration risk, regional analgesia at both ends of life, and the systems questions of allergy labels and bundled payment. Let's dive in.

We start with what our monitors are actually telling us. In Anesthesiology, Huz and colleagues interrogated end-tidal carbon dioxide in a retrospective cohort of more than 185,000 adults having noncardiac surgery under general anaesthesia with mechanical ventilation over a decade at a tertiary centre [1]. In-hospital mortality was low, under one percent, but the relationship with end-tidal carbon dioxide was striking and nonlinear: each five millimetre of mercury fall below the median was associated with roughly sixty percent higher adjusted odds of dying in hospital, and critically, that association held after adjustment for both minute ventilation and intraoperative hypotension, with no significant interaction between low carbon dioxide and low blood pressure. The authors' interpretation is that end-tidal carbon dioxide carries prognostic information beyond arterial pressure — a low value is not simply a ventilation artefact or a proxy for a soft blood pressure, but plausibly a window onto pulmonary perfusion and cardiac output. This is observational, so it cannot tell us that treating a low end-tidal carbon dioxide improves survival, but it argues that a persistently low number on the capnogram in a stable-looking patient deserves a deliberate thought rather than a dial adjustment. Also in Anesthesiology, Vistisen and colleagues offer a deflating look at the Hypotension Prediction Index literature [2]. They assembled twenty randomised trials covering just over 2,300 patients and asked a simple question: when these trials reduced hypotension, did they also increase haemodynamic treatment? Among the thirteen trials that reduced hypotension, nine — around seven in ten — also showed significantly more fluid, vasopressor or inotrope use in the intervention arm. Among the five trials that failed to reduce hypotension, not one showed increased treatment intensity. The association was statistically significant, and the magnitude of hypotension reduction correlated with treatment intensity. The implication is uncomfortable for the algorithm: these trials may largely be comparing two mean arterial pressure treatment thresholds with different aggressiveness attached, rather than demonstrating the value of prediction itself. If you are considering buying predictive haemodynamic software, the honest comparator is a protocol that simply intervenes earlier and harder on blood pressure.

Our second theme is airway and aspiration risk, and the standout comes from the British Journal of Anaesthesia. O'Brien and colleagues prospectively studied gastric ultrasound in adolescents aged ten to eighteen, comparing those on glucagon-like peptide-1 receptor agonists with an at-risk group not on these drugs and healthy controls [3]. Sixty-seven patients were analysed, all fasted well beyond guideline requirements — the median fast for solids was thirteen hours. In the receptor agonist group, sixteen of twenty adolescents, that is eighty percent, still had solid gastric contents on ultrasound. In the at-risk comparison group it was about sixty percent, and in healthy controls just one patient in twenty. The difference persisted after propensity adjustment for age, body mass index, sex, race and fasting time. Eighty percent of adolescents with solids in the stomach after more than twelve hours of fasting is a number that should change how you approach this rapidly growing paediatric population — standard fasting intervals cannot be assumed to empty the stomach, and point-of-care gastric ultrasound or a modified induction plan deserves serious consideration. Alongside that, Anesthesia and Analgesia published a large analysis from the Japanese Pediatric Difficult Airway Registry by Ichiyanagi and colleagues, covering more than 18,800 induction encounters across twelve tertiary hospitals [4]. Reassuringly, they found no association between any weight category and overall airway-related adverse events, which ran at about two percent throughout. But the secondary outcomes are where the signal sits: obesity roughly doubled the odds of a ten percent or greater desaturation, underweight status modestly increased it, and underweight children had meaningfully lower first-attempt intubation success — around eighty percent, compared with nearly ninety percent in normal-weight children. Extreme weight-for-age, in either direction, is a useful flag for who needs your most experienced hands and your best preoxygenation. Which dovetails with a Continuing Professional Development module in the Canadian Journal of Anesthesia from Schellekens and colleagues on high-flow nasal oxygen across anaesthesia practice [5]. The review is a practical one: high-flow nasal oxygen improves oxygenation and can extend safe apnoea time, its effect depends on airway patency and whether the mouth is open or closed, and the principal hazard is progressive hypercapnia during prolonged apnoea. Worth a read before your next shared-airway or sedation list.

Third, regional and analgesic techniques, at both ends of the age spectrum. In Anaesthesia, Smits and colleagues report a prospective multicentre Dutch cohort of 103 patients with hip fracture managed non-operatively — mean age eighty-seven, half of them nursing home residents, three quarters with cognitive impairment — treated with a pericapsular nerve group block using six percent phenol for chemical neurolysis [6]. At one week, thirty-four of thirty-six patients reporting were at acceptable pain at rest, and around nine in ten reported no or acceptable pain during washing and dressing; nearly half of those assessed could manage a bed-to-chair transfer. No procedure-related adverse events occurred. The context is essential: thirty-day mortality was sixty-two percent and median survival was nine days. This is palliative analgesia for a dying population, and on those terms it looks like a genuinely useful addition to the toolkit when surgery has been declined. From Regional Anesthesia and Pain Medicine, Taenzer and colleagues tackled a long-running controversy — does caudal block increase urethrocutaneous fistula after hypospadias repair [7]. Across sixteen Pediatric Regional Anesthesia Network centres, 210 children under two were randomised to caudal or penile block, with 161 completing three-month follow-up. Fistula rates were about nine percent with caudal and about seven percent with penile block, with no statistically significant difference — but the trial terminated early, follow-up was incomplete, and the authors are explicit that clinically important differences cannot be excluded and the findings should be read as exploratory. What was clear is that caudal block reduced intraoperative opioid use, from roughly half of patients down to a third, reduced rescue opioids, and lowered recovery room pain scores. And severity mattered more than the block: a proximal meatal position was associated with nearly triple the fistula risk. Rounding out the analgesia theme, Anesthesia and Analgesia published a double-blinded randomised trial from Berger and colleagues comparing dexamethasone eight milligrams with ondansetron four milligrams as first-line antiemetic after caesarean delivery under spinal with intrathecal morphine [8]. In ninety-five patients completing the trial, there was no difference in the total number of medications given for nausea, pain or pruritus in the first twenty-four hours, and no significant difference in pain scores. This is a negative trial in a small sample within an enhanced recovery protocol where baseline pain and nausea were already low — it does not establish dexamethasone's superiority, and it does not exclude a benefit in a higher-symptom population.

Finally, two papers about the system we work in. Savic and colleagues, in the British Journal of Anaesthesia, prospectively followed 13,646 patients across twenty-one National Health Service hospitals undergoing common surgical procedures [9]. Twenty-nine percent carried at least one drug allergy label — most of which, the authors note, are likely incorrect. Labelled patients had about a fifth higher odds of thirty-day postoperative complications, with a quarter of them experiencing the composite outcome versus one in five of the unlabelled; they had more surgical site infections, more infections overall, and roughly triple the odds of an allergic drug reaction. There was no excess mortality. That is a strong argument for treating the allergy label itself as a modifiable perioperative risk factor and for building de-labelling into preoperative pathways. And in Anesthesiology, Ghoshal and colleagues review Medicare's Transforming Episode Accountability Model for 2026 through 2030 [10], under which anaesthesia reimbursement sits inside a surgical bundle with episode-level accountability for cost and outcomes. The message for United States practice is that prevention of complications and perioperative optimisation — long undervalued under fee-for-service — become financially visible, and that we need to define and report outcomes that capture our contribution.

If you only have time for one paper this week, make it the gastric ultrasound study in adolescents on GLP-1 receptor agonists [3]. The prevalence of these drugs in young people is climbing fast, and an eighty percent rate of residual solids after a thirteen-hour fast is the kind of finding that should reshape your induction plan tomorrow.

Here are the key takeaways from this week in Anesthesiology. A low intraoperative end-tidal carbon dioxide carries mortality information independent of blood pressure and ventilation — treat it as a signal, not noise. The apparent benefit of hypotension prediction software travels with more aggressive haemodynamic treatment, so compare it against an earlier, firmer blood pressure threshold before you buy. Adolescents on GLP-1 receptor agonists are very often full despite prolonged fasting; scan the stomach or plan accordingly. Extreme weight-for-age in children flags desaturation risk and, if underweight, harder first-attempt intubation. Caudal block after hypospadias repair showed no significant fistula excess in an underpowered, early-terminated trial while reducing opioids — reassuring, not definitive. And a drug allergy label is associated with measurably worse surgical outcomes, which makes de-labelling a perioperative intervention, not a paperwork exercise.

That's your roundup for This Week in Anesthesiology. The full transcript and references are available on the episode page in your AudioScholar library. This is an AI-curated summary — for clinical decisions, always consult primary sources and current guidelines. See you next week.

If this weekly briefing is useful, follow the show in your podcast app so new episodes arrive automatically. And a quick rating on Apple Podcasts or Spotify helps other physicians discover the show.

This is an automated summary generated by artificial intelligence, which can make mistakes. Always review the original source materials.