Length of stay and hospitalization costs for patients undergoing lung surgery with Progel pleural air leak sealant

Lung-Mimetic Hydrofoam Sealant to Treat Pulmonary Air Leak

Pulmonary air leak is the most common complication of lung surgery, contributing to post-operative morbidity in up to 60% of patients; yet, there is no reliable treatment. Available surgical sealants do not match the demanding deformation mechanics of lung tissue; and therefore, fail to seal air leak. To address this therapeutic gap, a sealant with structural and mechanical similarity to subpleural lung is designed, developed, and systematically evaluated. This "lung-mimetic" sealant is a hydrofoam material that has alveolar-like porous ultrastructure, lung-like viscoelastic properties (adhesive, compressive, tensile), and lung extracellular matrix-derived signals (matrikines) to support tissue repair. In biocompatibility testing, the lung-mimetic sealant shows minimal cytotoxicity and immunogenicity in vitro. Human primary monocytes exposed to sealant matrikines in vitro upregulate key genes (MARCO, PDGFB, VEGF) known to correlate with pleural wound healing and tissue repair in vivo. In rat and swine models of pulmonary air leak, this lung-mimetic sealant rapidly seals air leak and restores baseline lung mechanics. Altogether, these data indicate that the lung-mimetic sealant can effectively seal pulmonary air leak and promote a favorable cellular response in vitro.

Impact of PEG sensitization on the efficacy of PEG hydrogel-mediated tissue engineering

While poly(ethylene glycol) (PEG) hydrogels are generally regarded as biologically inert blank slates, concerns over PEG immunogenicity are growing, and the implications for tissue engineering are unknown. Here, we investigate these implications by immunizing mice against PEG to stimulate anti-PEG antibody production and evaluating bone defect regeneration after treatment with bone morphogenetic protein-2-loaded PEG hydrogels. Quantitative analysis reveals that PEG sensitization increases bone formation compared to naive controls, whereas histological analysis shows that PEG sensitization induces an abnormally porous bone morphology at the defect site, particularly in males. Furthermore, immune cell recruitment is higher in PEG-sensitized mice administered the PEG-based treatment than their naive counterparts. Interestingly, naive controls that were administered a PEG-based treatment also develop anti-PEG antibodies. Sex differences in bone formation and immune cell recruitment are also apparent. Overall, these findings indicate that anti-PEG immune responses can impact tissue engineering efficacy and highlight the need for further investigation.

Clinical and Economic Burden Associated with Prolonged Air Leaks Among Patients Undergoing Thoracic Resection: A Retrospective Database Analysis

Purpose

Prophylactic use of lung sealants among patients undergoing thoracic resection has been reported for the management of intraoperative air leaks and is associated with a lower incidence of prolonged air leak (PAL) and a shorter length of stay (LOS). This study estimated the incremental economic and clinical burden of PAL among patients with lung sealants used during thoracic resection in the United States.

Patients and Methods

This retrospective analysis examined hospital data (Premier Healthcare Database) for adults (age ≥18 years) with inpatient thoracic resection between October 2015 - March 2021 (first admission=index) and lung sealant used during their procedure. Follow-up extended through 90 days post-discharge. Patients were grouped by presence/absence of PAL (ie, diagnosis of post-procedural air leak or post-procedural pneumothorax with associated LOS exceeding 5 days). Outcomes included intensive care unit (ICU) days, total index hospital costs, all-cause 30-, 60-, and 90-day readmission, discharge status, and in-hospital mortality. Generalized linear models quantified associations between PAL and outcomes, accounting for hospital-level clustering, and patient, procedure, and hospital/provider characteristics.

Results

Among the 9727 patients included for study (51.0% female, 83.9% white, mean age 66 years), 12.5% had PAL, which was associated with significant incremental increases in ICU days (0.93 days, p<0.001) and total hospital cost ($11,119, p<0.001). PAL also decreased the likelihood of discharge to home (from 91.3% to 88.1%, p<0.001) and increased the risk of readmission within 30, 60, and 90 days by up to 34.0% (from 9.3% to 12.6%;11.7% to 15.4%;13.6% to 17.2%, respectively), all p<0.01. Absolute risk of mortality was low, but two times higher in patients with PAL versus those without PAL (2.4% vs 1.1%, p=0.001).

Conclusion

This analysis demonstrates that despite the prophylactic use of lung sealants, PAL continues to put a burden on the healthcare system, highlighting an unmet need for improved sealant technology.

Composition, host responses and clinical applications of bioadhesives

Bioadhesives are medical devices used to join or seal tissues that have been injured or incised. They have been classified into tissue adhesives, sealants, and hemostatic agents. Bioadhesives such as FloSeal®, CoSeal®, BioGlue®, Evicel®, Tisseel®, Progel™ PALS, and TissuGlu® have been commercialized and used in clinical setting. They can be formulated with natural or synthetic components or a combination of both including albumin, glutaraldehyde, chitosan, cyanoacrylate, fibrin and thrombin, gelatin, polyethylene glycol (PEG), along with urethanes. Each formulation has intrinsic properties and has been developed and validated for a specific application. This review article briefs the mechanisms by which bioadhesives forms adhesion to tissues and highlights the correlation between bioadhesives composition and their potential host responses. Furthermore, clinical applications of bioadhesives and their application-driven requirements are outlined.

Successful Closure of Post-pneumonectomy Bronchopleural Fistula With Suture Repair Reinforced With Porcine Acellular Dermal Matrix (Permacol) and Hydrogel Sealant (Progel): A Case Report

Bronchopleural fistula (BPF) is a feared and potentially life-threatening complication of pneumonectomy. Clinical features such as a productive cough and subcutaneous emphysema raise suspicion of BPF with CT imaging and bronchoscopy providing a definitive diagnosis. In light of the significant morbidity and mortality associated with the condition, a significant proportion of cases necessitate surgical repair of the bronchial stump.

Currently, there is no consensus on optimal surgical strategy. Traditionally, various vascularised tissue flaps, including pericardial fat pad, omentum, and muscle, have been used to buttress the repaired stump, with varying success rates. In light of this, novel approaches have been devised with the aim of achieving more consistent surgical outcomes. In this case report, we describe a novel approach to reinforcing the suture repair using porcine dermal collagen matrix (Permacol, Medtronic, Minneapolis, MN) and hydrogel sealant (Progel, BD, Franklin Lakes, NJ) to achieve successful closure of a BPF in an adult male patient following pneumonectomy for squamous cell carcinoma.

The use of porcine dermal collagen matrix covered with hydrogel sealant is a viable alternative to traditional BPF closure strategies and can achieve good patient outcomes. This technique has several benefits including cost-effectiveness and sparing of native tissues, and it is technically straightforward. Further studies are required to compare the clinical outcomes of this and other novel techniques with traditional BPF closure approaches.

Polymeric Tissue Adhesives

Polymeric tissue adhesives provide versatile materials for wound management and are widely used in a variety of medical settings ranging from minor to life-threatening tissue injuries. Compared to the traditional methods of wound closure (i.e., suturing and stapling), they are relatively easy to use, enable rapid application, and introduce minimal tissue damage. Furthermore, they can act as hemostats to control bleeding and provide a tissue-healing environment at the wound site. Despite their numerous current applications, tissue adhesives still face several limitations and unresolved challenges (e.g., weak adhesion strength and poor mechanical properties) that limit their use, leaving ample room for future improvements. Successful development of next-generation adhesives will likely require a holistic understanding of the chemical and physical properties of the tissue-adhesive interface, fundamental mechanisms of tissue adhesion, and requirements for specific clinical applications. In this review, we discuss a set of rational guidelines for design of adhesives, recent progress in the field along with examples of commercially available adhesives and those under development, tissue-specific considerations, and finally potential functions for future adhesives. Advances in tissue adhesives will open new avenues for wound care and potentially provide potent therapeutics for various medical applications.

Predicting a Prolonged Air Leak After Video-Assisted Thoracic Surgery, Is It Really Possible?

Validation of predictive risk models for prolonged air leak (PAL) is essential to understand if they can help to reduce its incidence and complications. This study aimed to evaluate both the clinical and statistical performances of 4 existing models. We selected 4 predictive PAL risk models based on their scientific relevance. We referred to these models as Chicago, Bordeaux, Leeds and Pittsburgh model, respectively, according to the affiliation place of the first author. These predicting risk models were retrospectively applied to patients recorded on the second edition of the Italian Video-Assisted Thoracoscopic Surgery Group registry. Predictions for each patient were calculated based on the logistic regression coefficient values provided in the original manuscripts. All models were tested for their overall performance, discrimination, and calibration. We recalibrated the original models with the re-estimation of the model intercept and slope. We used curve decision analysis to describe and compare the clinical effects of the studied risk models. Better statistical metrics characterize the models developed on larger populations (Chicago and Bordeaux models). However, no model has a valid benefit for threshold probability greater than 0.30. The Net benefit of the most performing model (Bordeaux model) at the threshold probability of 0.11 is 23 of 1000 patients, burdened by 333 false positive cases. One of 1000 is the Net benefit at the threshold probability of 0.3. The use of PAL scores based on preoperative predictive factors cannot be currently used in a clinical setting because of a high false positive rate and low positive predictive value.

Surgical applications of intracorporal tissue adhesive agents: current evidence and future development

Introduction: Traditional mechanical closure techniques pose many challenges including the risk of infection, tissue reaction, and injury to both patients and clinicians. There is an urgent need to develop tissue adhesive agents to reform closure technique. This review examined a variety of tissue adhesive agents available in the market in an attempt to gain a better understanding of intracorporal tissue adhesive agents as medical devices.Areas covered: Fundamental principles and clinical determinants of the tissue adhesives were summarized. The available tissue adhesives for intracorporal use and their relevant clinical evidence were then presented. Lastly, the perspective of future development for intracorporal tissue adhesive were discussed. Clinical evidence shows current agents are efficacious as adjunctive measures to mechanical closure and these agents have been trialed outside of clinical indications with varied results.Expert opinion: Despite some advancements in the development of tissue adhesives, there is still a demand to develop novel technologies in order to address unmet clinical needs, including low tensile strength in wet conditions, non-controllable polimerization and sub-optimal biocompatibility. Research trends focus on producing novel adhesive agents to remit these challenges. Examples include the development of biomimetic adhesives, externally activated adhesives, and multiple crosslinking strategies. Economic feasibility and biosafety are limiting factors for clinical implementation.

Factors Associated With Hospitalization Costs of Coronary Heart Disease in Township Hospitals in Rural China

In large proportions of rural areas in many developing countries, health care delivery system is less developed and is less likely to be equipped to conduct sophisticated treatment for coronary heart disease (CHD) patients locally. This study aims at describing the status quo of and exploring factors associated with hospitalization costs of CHD in township hospitals where only drug therapy was available for CHD conditions. We collected data of inpatients with CHD from discharge records from 10 township hospitals in rural Liaoning from December 2013 to December 2014. We used multilevel linear regression to analyze the factors associated with CHD hospitalization costs. A total of 4635 inpatients were included in the analysis. We found that the average hospitalization costs were 6249.97 RMB (US$1012.47) with the average of 8.89 days of hospitalization in township hospitals in Liaoning. Age, gender, length of stay, the number of times of admissions, by which route was hospitalized, and type of CHD were all the factors significantly associated with hospitalization costs of CHD in township hospitals. The factors associated with hospitalization costs of CHD in township hospitals in rural China showed some different features from the existing studies. When the government designs the related policy, the policy makers need to consider the specific feature of hospitalization costs of CHD in township hospitals in rural areas.