Cuddling the Circuit: How Circuit Insulation Enhances Gas Delivery in Anesthesia, study finds

Recent study explores the effect of breathing circuit insulation on the conditioning of inspired gases and the condensation of water vapor during general anesthesia, utilizing an in vitro mechanical lung model. Insufficient temperature and humidity of inspired gases may lead to mucus membrane dehydration, ciliary dysfunction, retention of secretions, and potential atelectasis, compromising postoperative pulmonary function. The methodology involved comparing three types of insulation (foam, cotton, and polyester) against non-insulated tubing (control), with measurements taken for temperature, absolute humidity (AH), and water vapor condensation after 120 minutes. The analysis employed Bonferroni-Holm adjustments to account for multiple testing.

Results of Insulation Performance

Results indicated enhanced performance of foam insulation, which resulted in higher temperatures and AH compared to the control and the other insulation types. Specifically, foam insulation elevated the mean temperature significantly (P < 0.001), achieving a mean difference of 1.07 °C from the control, while the cotton and polyester insulations also provided temperature elevations but fell short of the target range of 28-32 °C optimal for perioperative ventilation. Despite all insulation types improving AH levels significantly over the control, none reached the target levels, although they effectively exceeded 20 g•m-3 H2O.

Water Vapor Condensation Analysis

Water vapor condensation was markedly reduced in insulated circuits, with foam insulation demonstrating the lowest condensation rate at 1.59 mL•h-1, compared to 2.95 mL•h-1 in the control and 2.26 and 2.32 mL•h-1 in cotton and polyester, respectively. A strong negative correlation was observed between the amount of water vapor condensation and temperature increases.

Implications and Future Research

The study emphasizes the necessity of achieving adequate conditioning of inspired gases to mitigate complications arising from dry and cold gases during anesthesia. Limitations included the technical constraints of the mechanical lung model, such as a lack of physiological conditions, which may affect the external validity of the findings. Future research, ideally in vivo, is warranted to further investigate the clinical implications of insulation types concerning inspired gas conditioning in real-world anesthesia contexts.

Conclusions and Recommendations

Overall, the findings support the potential application of insulated breathing circuits as a method to enhance the conditioning of inspired gases under low-flow anesthesia, although achieving optimal clinical standards remains a challenge. The results advocate for foam insulation as the most effective option, encouraging further investigation into its practical applications in anesthetic practice.

Key Points

– The study evaluates the role of different insulation materials (foam, cotton, polyester, and control) on the conditioning of inspired gases during general anesthesia using an in vitro mechanical lung model, focusing on temperature and absolute humidity levels to prevent complications such as mucus membrane dehydration and postoperative pulmonary dysfunction.

– Foam insulation significantly outperformed the control and other materials, achieving a mean temperature increase of 1.07 °C (P < 0.001) but still failed to reach the optimal perioperative range of 28-32 °C; all insulation types improved absolute humidity but did not attain the ideal threshold, remaining above 20 g•m-3 H2O.

– Water vapor condensation rates were significantly lower in insulated circuits, with foam insulation recording the most effective performance at 1.59 mL•h-1, followed by cotton (2.26 mL•h-1) and polyester (2.32 mL•h-1), while the control exhibited the highest condensation rate at 2.95 mL•h-1; a negative correlation was noted between condensation rates and temperature increases.

– The investigation highlights the importance of proper conditioning of inspired gases to reduce the risk of adverse effects associated with poor thermal and humidity management in anesthetic practices, indicating a potential clinical significance for insulated breathing circuits.

– Limitations of the study were acknowledged, particularly the artificiality of the mechanical lung model, which may not fully replicate physiological conditions, suggesting that the external validity of the findings could be constrained.

– Future studies, ideally conducted in vivo, are proposed to further explore the clinical relevance of different insulation types in achieving optimal inspired gas conditioning in anesthesia, particularly focusing on the practical implementation of foam insulation in clinical settings.

Reference –

Nguyen-Minh, T., Hönemann, C., Zarbock, A. et al. Effects of breathing circuit insulation on inspired gas conditioning and water vapour condensation: an in vitro study. Can J Anesth/J Can Anesth 72, 780–790 (2025). https://doi.org/10.1007/s12630-025-02959-7

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Young Breast Cancer Patients Have Low Risk of Isolated Locoregional Recurrence After Surgery: JAMA

USA: A large retrospective study found that young women diagnosed with breast cancer have a relatively low risk of isolated locoregional recurrence (LRR) after initial treatment. Researchers concluded that long-term LRR risk should not influence surgical decision-making in this population.

Published in JAMA Surgery, the study was led by Dr. Laura S. Dominici from the Division of Breast Surgery at Brigham and Women’s Hospital, Boston, along with colleagues from the multicenter Young Women’s Breast Cancer Study. It aimed to evaluate the long-term rates of isolated LRR based on molecular subtypes in women aged 40 or younger at the time of diagnosis.

The cohort included 1,135 women with stage I to III breast cancer, diagnosed between 2006 and 2016. The median follow-up was 10.1 years, making it one of the most comprehensive evaluations of long-term outcomes in this demographic. Over the follow-up period, 59 patients experienced isolated local recurrence (5.2%), and four had isolated regional recurrence (0.4%), leading to an overall LRR rate of 5.6%.

Participants were stratified by age at diagnosis: 12.8% were under 30 years, 28% were aged 31 to 35, and the remaining 59.2% were between 36 and 40. The study also accounted for molecular subtypes and types of local therapy, such as breast-conserving treatment (BCT), unilateral mastectomy, and bilateral mastectomy.

Based on the study, the researchers reported the following findings:

  • Among the participants, 32% had luminal A–like tumors, 21% had luminal B–like tumors, 20% had luminal ERBB2-positive (formerly HER2-positive) tumors, 8% were ERBB2-positive, and 18% had triple-negative breast cancer.
  • Despite the variation in tumor subtypes, the cumulative incidence of isolated locoregional recurrence (LRR) remained low across all groups.
  • The LRR rates ranged from 2.2% in ERBB2-positive cases to 6.5% in patients with triple-negative breast cancer.
  • At the 10-year mark, LRR occurred in 6.7% of women who received breast-conserving therapy (BCT).
  • The LRR rate was 6.5% in women who underwent mastectomy without radiation.
  • The lowest LRR rate of 2.4% was observed in those who had mastectomy with radiation.
  • Although mastectomy with radiation showed the lowest recurrence rate in multivariable analysis, no significant differences in LRR were found when treatment outcomes were evaluated within individual molecular subtypes.

The findings challenge the long-held belief that young women with breast cancer are at a markedly higher risk of recurrence regardless of treatment strategy. Instead, this study suggests that surgical choices should not be dictated by concerns over long-term recurrence alone.

Researchers emphasized that these results underscore the importance of personalized treatment planning, rather than defaulting to more aggressive surgical approaches based solely on age or tumor subtype. The relatively low incidence of recurrence over a decade post-diagnosis supports shared decision-making that aligns with patient preferences and overall health goals.

Reference:

Dominici LS, Zheng Y, King TA, et al. Long-Term Locoregional Outcomes in a Contemporary Cohort of Young Women With Breast Cancer. JAMA Surg. Published online July 23, 2025. doi:10.1001/jamasurg.2025.2324

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Low-dose three-phase brain perfusion imaging and AI-based parameter map generation:Study

Computed Tomography Perfusion (CTP) is a critical tool for rapidly evaluating brain blood flow in suspected stroke patients, guiding time-sensitive treatment decisions. However, standard CTP requires continuously scanning the brain over 40-60 seconds, capturing numerous time points. This results in high cumulative radiation doses, poses risks for patients with kidney problems due to the contrast agent load, and is sensitive to patient movement, leading to complex processing and potential failure. While reducing the number of scans seems logical, randomly skipping time points often misses crucial peaks in blood flow, severely underestimating key parameters. Thus, how to optimize scanning protocols to reduce CTP radiation dose and address the complexity of current functional imaging processes are urgent issues to address.

Now, team from the First Affiliated Hospital of Jinan University and Southern Medical University, have developed an innovative CTP scanning protocol and a deep learning model that can generate the vital blood flow maps needed to assess stroke patients. This work has proofed the proposed low radiation dose imaging program can slash radiation exposure by over 80% compared to current methods. This innovation promised to make stroke diagnosis safer and more accessible, particularly for vulnerable patients.

Addressing Limitations in Conventional CTP

Despite its clinical value, traditional CTP is associated with significant drawbacks. These include:

  1. High Radiation Dose: Conventional protocols can reach cumulative doses around 5260 mGy·cm, notably higher than CTA (~3222 mGy·cm).
  2. Motion Sensitivity: Repeated scans across timepoints make the technique vulnerable to patient motion, requiring sophisticated registration algorithms.
  3. Workflow Complexity: The image processing burden and risk of failure hinder routine use in clinical settings.

Previous strategies for reducing radiation via temporal subsampling risk omitting critical arterial enhancement peaks, underestimating hemodynamic parameters. While multiphase CTA (mCTA) has shown promise in capturing arterial and venous phases, it requires large contrast volumes (~80 mL), posing risks for patients with impaired renal function, and lacks quantitative perfusion data.

A Three-Phase CTP with Deep Learning Enhancement

Inspired by the temporal structure of mCTA, the team introduced a three-phase CTP protocol that drastically reduces temporal sampling while preserving essential perfusion information. A generative adversarial network (GAN)-based model was developed to directly synthesize perfusion parameter maps from only three timepoints.

In internal validation datasets, the model-produced maps showed high structural and perceptual fidelity compared to ground truth, demonstrating its capability to reconstruct key perfusion features. Further experiments explored how variations in the selected three-phase combinations affected performance. Even with ±2-second deviations from the ideal timepoints, the model maintained high predictive accuracy, although performance dropped with deviations beyond 4 seconds. These findings support both the practical feasibility of the protocol and the robustness of the model.

Reference:

Cuidie Zeng, Xiaoling Wu, Fusheng Ouyang, Baoliang Guo, Xiao Zhang, Jianghua Ma, Dong Zeng, Bin Zhang. Perfusion Parameter Map Generation from 3 Phases of Computed Tomography Perfusion in Stroke Using Generative Adversarial Networks. Research. 2025;8:0689.DOI:10.34133/research.0689.

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A media–public disconnect exists on wild meat narratives in central Africa during COVID-19

A new study published by researchers from the University of Oxford, the Wildlife Conservation Society (WCS), CIFOR-ICRAF, and institutional partners reveals a disconnect between media and public perceptions of the risks of consuming wild meat in Central Africa during COVID-19, and sheds light on the complex relationship between media reporting, community beliefs, and behavior change—offering important lessons for wildlife management and public health strategies.

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Intense, persistent grief linked to nearly double mortality risk over 10 years

Grief after the loss of a loved one is a natural response—an inevitable part of living and loving. But in a minority of the bereaved, grief is so overwhelming that it can lead to physical and mental illness, even if they don’t necessarily qualify for a diagnosis of the mental health condition of prolonged grief disorder. For example, studies have shown that people who recently lost a loved one use health care services more often, and have an increased mortality rate over the short term.

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Long-term exposure to outdoor air pollution linked to increased risk of dementia

An analysis of studies incorporating data from almost 30 million people has highlighted the role that air pollution—including that coming from car exhaust emissions—plays in increased risk of dementia.

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TyG Index Potential Marker for evaluating kidney function and Diabetic Kidney Disease: Study

A new study published in the Journal of Diabetes & Metabolic Disorders found TyG Index as an indicator for diabetic kidney disease (DKD) in individuals with type 2 diabetes (T2D), highlighting its potential clinical use in evaluating renal function deterioration.

Diabetes continues to have an unacceptably high incidence worldwide, with a steady upward trend. The mortality of diabetes patients and the frequency of cardiovascular events are significantly impacted by end-stage renal disease (ESRD). A higher percentage of people with type 2 diabetes experience DKD than those with type 1 diabetes.

Numerous cardiovascular conditions, including atherosclerosis, acute coronary syndrome, and heart failure, have been discovered to be strongly correlated with the TyG index, a new measure generated from triglycerides (TG) and fasting plasma glucose (FPG). TyG Index is a straightforward indicator of insulin resistance. It is unknown how it affects the development of diabetic kidney disease (DKD) in people with type 2 diabetes. Thus, this study examined the relationship between the TyG index and the advancement of DKD in T2D.

This study included 428 T2D patients with and without DKD. According to the Kidney Disease Improving Global Outcomes (KDIGO) criteria, the progression of DKD was determined. The TyG index was used to separate patient demographic data into quartiles. The relationship between the TyG Index and metabolic markers was examined using multiple regression.

According to the findings, 257 individuals (60.0%) experienced DKD. The TyG index was considerably higher in the DKD group than in the non-DKD group (9.9 ± 0.7 vs. 9.4 ± 0.6, P < 0.001). Age, systolic blood pressure, glycated hemoglobin, triglycerides, urea, total cholesterol, uric acid, LDH, creatinine, albumin creatinine ratio, and TyG index (P < 0.05 for each), glycated hemoglobin, triglycerides, and eGFR were all lower in the DKD group.

An elevated TyG index was identified as an independent risk factor for DKD. Overall, the TyG Index may be an indication of DKD in T2D patients. This data confirms the clinical value of TyG index in evaluating renal function worsening in DKD patients.

Source:

Siddiqui, K., Nawaz, S. S., George, T. P., David, S. K., Alfadda, A. A., & Rafiullah, M. (2025). Association of triglyceride-glucose index with diabetic kidney disease in patients with type 2 diabetes. Journal of Diabetes and Metabolic Disorders, 24(2), 171. https://doi.org/10.1007/s40200-025-01680-y

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FDA approves first cream for treating chronic hand eczema

The U.S. Food and Drug Administration (FDA) has signed off on the first-ever cream specifically approved for treating chronic hand eczema (CHE).

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Research findings could improve outcomes for critically ill patients on ventilators, study finds

A seven-year international, multi-center clinical trial led by London Health Sciences Centre Research Institute (LHSCRI) and St. Michael’s Hospital, a site of Unity Health Toronto, has found that a new ventilation mode called proportional assist ventilation (PAV+) could improve outcomes for patients in the intensive care unit (ICU) who require help breathing. The study is published in the New England Journal of Medicine.

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Tezepelumab effective as Add-On Therapy in Both T2-High and T2-Low Severe Asthma: Study

According to a real-world study, tezepelumab is an effective add-on biologic with a rapid onset of action for patients with both T2-high and T2-low severe asthma. The study was published in International Immunopharmacology by Pelaia and colleagues.

The trial involved 30 patients who had been diagnosed with either T2-high or T2-low severe asthma. Patients were evaluated at baseline and subsequently after 4 weeks of tezepelumab add-on therapy. The clinical symptom control, asthma-related quality of life, lung function, inflammatory biomarkers, and use of oral corticosteroid (OCS) were among the assessments. The participants were recruited from a single centre and comprised those who had and had not received prior treatment with other biologic drugs.

Markers of inflammation also showed significant reductions. Fractional exhaled nitric oxide (FeNO), the eosinophilic airway inflammation biomarker, declined significantly. Counts of blood basophils, another indicator of allergic and inflammatory reaction, also decreased. In cytokines, serum levels of interleukin-2 (IL-2) and vascular endothelial growth factor (VEGF) were significantly decreased, evidencing the extensive immunomodulatory actions of tezepelumab.

Key Findings

 • 30 patients with severe asthma were assessed

• Substantial symptom improvement quantified by ACT score and AQLQ

• Improved lung function: FEV1, FEF25–75, and Rtot

• Reduced inflammatory markers: FeNO, basophil count

• Decreased cytokines: IL-2, VEGF

• Effects observed in both T2-high and T2-low patients

• Beneficial regardless of previous biologic use

Efficacy Across Asthma Phenotypes

Significantly, the study confirmed that the benefits of tezepelumab extended to both T2-high and T2-low phenotypes of severe asthma. In addition, the drug’s efficacy was unaffected in patients whether they had been exposed to prior use of other biologic medicines or not. This highlights tezepelumab’s sole strength: it neither depends on eosinophilic nor allergic biomarkers to act on patients with severe asthma. Hence, it is a therapy universally applicable across all cases of severe asthma.

In this real-world investigation, tezepelumab demonstrated rapid and robust improvements in asthma control, lung function, and inflammatory markers for both T2-high and T2-low phenotypes. Its efficacy, irrespective of previous biologic exposure, attests to its utility as a useful add-on treatment with widespread use in severe asthma. Future long-term research may further confirm such encouraging initial findings and optimize its placement within asthma treatment guidelines.

Reference:

Pelaia, C., Greco, M., Iaccino, E., Crimi, C., Biafora, M., Dragone, F., Vatrella, A., & Pelaia, G. (2025). Short-term therapeutic effectiveness of tezepelumab in patients with severe asthma: A real-world study. International Immunopharmacology, 162(115185), 115185. https://doi.org/10.1016/j.intimp.2025.115185

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