Anesth. Res., Volume 2, Issue 2 (June 2025) – 5 articles

Objectives: Comparative analyses of anesthetic agents on mutants with altered anesthetic sensitivity remain limited in the current literature. This study examines the sensitivity of various Drosophila melanogaster wild-type strains and mutants to the volatile anesthetics chloroform and isoflurane. We utilized recently identified mutants in ion channel-encoding genes and others historically selected for anesthetic resistance, such as AGAR (autosomal general anesthesia resistant) and har (halothane-resistant). Method: Based on the principles of the conventional inebriometer assay used to isolate these mutants, we developed a new, simpler method to measure the anesthetic response in these flies. Results: Interestingly, we discovered that wild-type flies exhibit varying levels of anesthetic resistance. Contrary to previous reports, AGAR and har mutants showed little resistance to anesthesia using our method. Several ion channel mutants displayed increased resistance or sensitivity. Across all strains, isoflurane was more potent than chloroform. To ensure objectivity, all experiments were conducted double-blind. These findings highlight the variability in anesthetic sensitivity among both wild-type and mutant flies and underscore the importance of assay design in assessing resistance. Full article

Background/Objectives: Postoperative delirium has not been well explored in patients undergoing elective hip and knee arthroplasty. This study assessed the incidence of delirium in these patients in the postanesthetic care unit (PACU) and throughout their hospital admission. Predictors of postoperative delirium and impact of delirium on length of stay were also analyzed. Methods: This prospective observational study recruited patients (n = 978) with normal cognitive function presenting for elective primary hip or knee arthroplasty at a single tertiary academic center. Delirium was assessed using the Nursing Delirium Scoring Scale (NuDESC) in the PACU, and twice daily after that on postoperative days 1, 2 and 3, or until discharge, whichever came first. Results: In total, 26 (2.7%) patients developed delirium postoperatively. Unadjusted logistic regression analyses revealed that age; history of cardiovascular, central nervous system, hematologic, endocrinologic, psychiatric disease; postoperative opioid use; and ASA level were associated with an increased risk of delirium, with odds ratios (95% confidence interval) of 1.7 (1.35 to 2.11), 3.6 (1.09 to 12.25), 3.5 (1.53 to 8.03), 2.7 (1.09 to 6.45), 2.3 (1.04 to 4.97), 4.7 (2.10 to 10.70), 0.4 (0.17 to 0.89), and 2.37 (1.05 to 5.33), respectively. A Mann–Whitney U test showed no difference in PACU or hospital length of stay between patients who did and did not have delirium in the PACU (within the first hour). Conclusions: Age, ASA > 3, a history of cardiovascular disease, central nervous system disease, hematologic disease, endocrinologic disease, psychiatric disease and postoperative opioid use are individually associated with postoperative delirium. A future study with an even larger sample size is needed to further evaluate these factors in an adjusted analysis. Full article

Introduction: In recent years, a greater number of adults have been undergoing spinal surgery. The main complications in the postanesthetic care unit (PACU) include respiratory and cardiovascular problems, pain, and nausea or vomiting. The aim of this study was to describe the preoperative characteristics and intra-anesthetic management of adult patients who underwent elective spinal surgery with balanced general anesthesia and to identify the predictive factors associated with supplemental oxygen requirement upon discharge from the PACU. In addition, we sought to develop a risk index on the basis of multivariable analysis allowing stratification of the probability of supplemental oxygen requirement upon discharge from the PACU. Materials and Methods: In this cross-sectional, retrospective, observational study, the pre- and intra-anesthetic characteristics of adult patients who underwent spinal surgery at any vertebral level under balanced general anesthesia in a tertiary hospital were retrieved. Descriptive statistics are provided, and comparison (Kruskal–Wallis) or correlation analyses (chi-square) were conducted between the characteristics of the patients grouped according to the need for supplemental oxygen upon discharge from the PACU. Receiver operating characteristic (ROC) curves and a multivariate logistic regression model were generated. All tests were performed at the α = 0.05 level. Results: Among 349 patients initially considered, only 211 were included in the analysis. A total of 45.50% of the patients who underwent spinal surgery under balanced general anesthesia required supplemental oxygen upon discharge from the PACU; these patients had significantly greater age, body mass index (BMI), surgery time, and anesthesia time. In addition, the use of norepinephrine and the use of fentanyl were associated with the need for supplemental oxygen. Our proposed risk index for predicting the need for supplemental oxygen upon discharge from the PACU, according to the implementation of a multivariable logistic model based on three simple variables (age ≥ 48 years, BMI ≥ 26.5, and use of fentanyl infusion), achieved an area under the curve (AUC) of 0.740. Conclusions: Age, BMI, and the use of fentanyl can be used to predict the need for supplemental oxygen upon discharge from the PACU. Multicenter and/or longitudinal studies with large sample sizes are needed to confirm the results of this study and improve the prediction of the need for supplemental oxygen upon discharge from the PACU. Full article

Background/Objectives: Propofol is a preferred agent for ICU sedation. Hypertriglyceridemia occurs in up to 45% of patients on propofol and has been linked with adverse effects. Data extrapolated from acute pancreatitis suggests intravenous (IV) insulin infusions may be effective in reducing serum triglyceride (TG) values in patients with propofol-induced elevated TG. The objective is to describe and compare serum TG levels in critically ill patients receiving concomitant insulin infusions and propofol versus propofol alone. Methods: This is a retrospective cohort study of mechanically ventilated adult patients admitted to a medical intensive care unit who received a propofol infusion alone or propofol and IV insulin infusions and who had a minimum of two serum TG levels while on propofol infusion. The primary outcome was median change in the serum TG concentration in patients receiving concomitant propofol and IV insulin infusions, as compared to those receiving propofol alone. Results: A total of 263 patients were screened and 32 met inclusion criteria (16 in each group). The median change between first and last obtained TG level was 0.35 (−0.31–1.33) vs. −0.07 (−1.08–+0.42) mmol/L (p = 0.051) in the propofol vs. propofol and IV insulin groups, respectively. Each day on propofol was associated with an estimated 0.21 mmol/L (95% confidence interval (CI) 0.0.004 to 0.41, p = 0.046) increase in TG, and each additional day of IV insulin was associated with a 0.14 mmol/L (95% CI −0.63 to 0.35, p = 0.571) decrease in TG. Conclusions: Each additional day of propofol was associated with an increase in serum TG levels. IV insulin infusions did not lead to a significant difference in triglyceride values. Full article

Background: Neuromuscular blocking agents play an important role in modern anesthesia by facilitating optimal surgical conditions through deep muscle relaxation. Additionally, neuromuscular monitoring and reversal ensure swift and reliable recovery from neuromuscular blockade. The evolution of neuromuscular blocking agents, from early curare derivatives to contemporary agents such as rocuronium and cisatracurium, has significantly enhanced the safety and efficacy of anesthesia. Methods: This review examines the historical development, pharmacological mechanisms, clinical applications, and innovations in managing neuromuscular blockade. Results: It underscores key milestones in the advancement of neuromuscular blockade, including the introduction of neuromuscular monitoring techniques like Train-of-Four, which improve patient safety by reducing residual neuromuscular blockade. Pharmacological advancements, particularly the emergence of sugammadex, have further revolutionized clinical practice by enabling rapid and reliable reversal of steroidal neuromuscular blocking agents. The discussion covers the role of deep neuromuscular blockade in optimizing surgical conditions, especially in minimally invasive procedures. Conclusion: Comparative analyses of standard versus deep blockade reveal potential advantages in certain surgical scenarios, although patient-specific factors and associated risks must be carefully evaluated. Future directions involve developing innovative neuromuscular blocking agents and reversal agents aimed at achieving faster onset, shorter duration, and fewer side effects. The management of neuromuscular blockade continues to evolve, propelled by advancements in pharmacology and monitoring technology. Anesthesiologists should embrace a personalized approach, integrating advanced monitoring tools and customized pharmacological strategies to enhance patient outcomes. Ongoing research into next-generation neuromuscular blocking agents and reversal agents holds the promise of further improving safety and efficiency in anesthesia practice. Full article