Hydrogels are known for their high water retention capacity and biocompatibility and have become essential materials in tissue engineering and drug delivery systems. This review explores recent advancements in hydrogel technology, focusing on innovative types such as self-healing, tough, smart, and hybrid hydrogels, each engineered to overcome the limitations of conventional hydrogels. Self-healing hydrogels can autonomously repair structural damage, making them well-suited for applications in dynamic biomedical environments. Tough hydrogels are designed with enhanced mechanical properties, enabling their use in load-bearing applications such as cartilage regeneration. Smart hydrogels respond to external stimuli, including changes in pH, temperature, and electromagnetic fields, making them ideal for controlled drug release tailored to specific medical needs. Hybrid hydrogels, made from both natural and synthetic polymers, combine bioactivity and mechanical resilience, which is particularly valuable in engineering complex tissues. Despite these innovations, challenges such as optimizing biocompatibility, adjusting degradation rates, and scaling up production remain. This review provides an in-depth analysis of these emerging hydrogel technologies, highlighting their transformative potential in both tissue engineering and drug delivery while outlining future directions for their development in biomedical applications.

Airway driving pressure, easily measured as plateau pressure minus PEEP, is a surrogate for alveolar stress and strain. However, the effect of its targeted reduction remains unclear. In this multicentre trial, patients undergoing lung resection surgery were randomised to either a driving pressure group (n=650) receiving an alveolar recruitment/individualised PEEP to deliver the lowest driving pressure or to a conventional protective ventilation group (n=650) with fixed PEEP of 5 cm H₂O. The primary outcome was a composite of pulmonary complications within 7 days postoperatively. The modified intention-to-treat analysis included 1170 patients (mean [standard deviation, sd]; age, 63 [10] yr; 47% female). The mean driving pressure was 7.1 cm H₂O in the driving pressure group vs 9.2 cm H₂O in the protective ventilation group (mean difference [95% confidence interval, CI]; -2.1 [-2.4 to -1.9] cm H₂O; P<0.001). The incidence of pulmonary complications was not different between the two groups: driving pressure group (233/576, 40.5%) vs protective ventilation group (254/594, 42.8%) (risk difference -2.3%; 95% CI, -8.0% to 3.3%; P=0.42). Intraoperatively, lung compliance (mean [sd], 42.7 [12.4] vs 33.5 [11.1] ml cm H₂O^-1; P<0.001) and Pa_o2 (median [inter-quartile range], 21.5 [14.5 to 30.4] vs 19.5 [13.5 to 29.1] kPa; P=0.03) were higher and the need for rescue ventilation was less frequent (6.8% vs 10.8%; P=0.02) in the driving pressure group. In lung resection surgery, a driving pressure-guided ventilation improved pulmonary mechanics intraoperatively, but did not reduce the incidence of postoperative pulmonary complications compared with a conventional protective ventilation. NCT04260451.

Purpose: Opioid-free anesthesia (OFA) is an emerging technique that eliminates intraoperative use of opioids and is associated with lower postoperative opioid consumption and reduced adverse postoperative events. The present study investigated the effect of OFA on the quality of recovery in patients undergoing gynecological laparoscopy. Patients and Methods: Seventy-five adult patients undergoing elective gynecological laparoscopy were randomly assigned to the OFA group with dexmedetomidine and lidocaine or the remifentanil-based anesthesia (RA) group with remifentanil. Patients, surgeons, and medical staff members providing postoperative care and assessing outcomes were blinded to group allocation. The anesthesiologist performing general anesthesia could not be blinded due to the different drug administration protocols by groups. The primary outcome was the quality of recovery measured using the Quality of Recovery-40 (QoR-40) questionnaire. Secondary outcomes were postoperative pain score, intraoperative and postoperative adverse events, and stress hormones levels. Results: The patients in both groups had comparable baseline characteristics. The QoR-40 score on postoperative day 1 was significantly higher in the OFA group than in the RA group (155.9 ± 21.2 in the RA group vs 166.9 ± 17.8 in the OFA group; mean difference: − 11.0, 95% confidence interval: − 20.0, − 2.0; p = 0.018). The visual analog scale score at 30 min after surgery was significantly lower in the OFA group than in the RA group (6.3 ± 2.3 in the RA group vs 4.1 ± 2.1 in the OFA group; p < 0.001). The incidences of nausea and shivering in the post-anesthetic care unit were also significantly lower in the OFA group (p = 0.014 and 0.025; respectively). Epinephrine levels were significantly lower in the OFA group (p = 0.002). Conclusion: OFA significantly improved the quality of recovery in patients undergoing gynecological laparoscopy.

Cancer recurrence and metastasis remain critical challenges following surgical resection, influenced by complex perioperative mechanisms. This review explores how surgical stress triggers systemic changes, such as neuroendocrine responses, immune suppression, and inflammation, which promote the dissemination of residual cancer cells and circulating tumor cells. Key mechanisms, such as epithelial–mesenchymal transition and angiogenesis, further enhance metastasis, while hypoxia-inducible factors and inflammatory responses create a microenvironment conducive to tumor progression. Anesthetic agents and techniques modulate these mechanisms in distinct ways. Inhaled anesthetics, such as sevoflurane, may suppress immune function by increasing catecholamines and cytokines, thereby promoting cancer progression. In contrast, propofol-based total intravenous anesthesia mitigates stress responses and preserves natural killer cell activity, supporting immune function. Opioids suppress immune surveillance and promote angiogenesis through the activation of the mu-opioid receptor. Opioid-sparing strategies using NSAIDs show potential in preserving immune function and reducing recurrence risk. Regional anesthesia offers benefits by reducing systemic stress and immune suppression, though the clinical outcomes remain inconsistent. Additionally, dexmedetomidine and ketamine exhibit dual effects, both enhancing and inhibiting tumor progression depending on the dosage and context. This review emphasizes the importance of individualized anesthetic strategies to optimize long-term cancer outcomes. While retrospective studies suggest potential benefits of propofol-based total intravenous anesthesia and regional anesthesia, further large-scale trials are essential to establish the definitive role of anesthetic management in cancer recurrence and survival.

Local anesthetics (LAs) have been indispensable in clinical pain management, yet their limitations, such as short duration of action and systemic toxicity, necessitate improved delivery strategies. Hydrogels, with their biocompatibility, tunable properties, and ability to modulate drug release, have been extensively explored as platforms for enhancing LA efficacy and safety. This narrative review explores the historical development of LAs, their physicochemical properties, and clinical applications, providing a foundation for understanding the integration of hydrogels in anesthetic delivery. Advances in thermoresponsive, stimuli-responsive, and multifunctional hydrogels have demonstrated significant potential in prolonging analgesia and reducing systemic exposure in preclinical studies, while early clinical findings highlight the feasibility of thermoresponsive hydrogel formulations. Despite these advancements, challenges such as burst release, mechanical instability, and regulatory considerations remain critical barriers to clinical translation. Emerging innovations, including nanocomposite hydrogels, biofunctionalized matrices, and smart materials, offer potential solutions to these limitations. Future research should focus on optimizing hydrogel formulations, expanding clinical validation, and integrating advanced fabrication technologies such as 3D printing and artificial intelligence-driven design to enhance personalized pain management. By bridging materials science and anesthetic pharmacology, this review provides a comprehensive perspective on current trends and future directions in hydrogel-based LA delivery systems.

Purpose: Postoperative delirium (POD) is a common but serious complication after cardiac surgery and is associated with various short- and long-term outcomes. In this study, we investigated the effects of intraoperative glycemic variability (GV) and other glycemic variables on POD after cardiac surgery. Patients and Methods: A retrospective single-center cohort analysis was conducted using data from electronic medical record from 2018 to 2020. A total of 705 patients undergoing coronary artery bypass graft surgery and/or valve surgery, and/or aortic replacement surgery were included in the analysis. Intraoperative GV was assessed with a coefficient of variation (CV), which was defined as the standard deviation of five intraoperative blood glucose measurements divided by the mean. POD assessment was performed three times a day in the ICU and twice a day in the ward until discharge by trained medical staff. POD was diagnosed if any of the Confusion Assessment Method for the Intensive Care Unit was positive in the ICU, and the Confusion Assessment Method was positive in the ward. Multivariable logistic regression was used to identify associations between intraoperative GV and POD. Results: POD occurred in 306 (43.4%) patients. When intraoperative glycemic CV was compared as a continuous variable, the delirium group had higher intraoperative glycemic CV than the non-delirium group (22.59 [17.09, 29.68] vs 18.19 [13.00, 23.35], p < 0.001), and when intraoperative glycemic CV was classified as quartiles, the incidence of POD increased as intraoperative glycemic CV quartiles increased (first quartile 29.89%; second quartile 36.67%; third quartile 44.63%; and fourth quartile 62.64%, p < 0.001). In the multivariable logistic regression model, patients in the third quartile of intraoperative glycemic CV were 1.833 times (OR 1.833, 95% CI: 1.132– 2.967, p = 0.014), and patients in the fourth quartile of intraoperative glycemic CV were 3.645 times (OR 3.645, 95% CI: 2.235– 5.944, p < 0.001) more likely to develop POD than those in the first quartile of intraoperative glycemic CV. Conclusion: Intraoperative blood glucose fluctuation, manifested by intraoperative GV, is associated with POD after cardiac surgery. Patients with a higher intraoperative GV have an increased risk of POD.