Synthesis, Characterization and Catechol-Based Bioinspired Adhesive Properties in Wet Medium of Poly(2-Hydroxyethyl Methacrylate-co-Acrylamide) Hydrogels.

Hydrogels consist of crosslinked hydrophilic polymers from which their mechanical properties can be modulated for a wide variety of applications. In the last decade, many catechol-based bioinspired adhesives have been developed following the strategy of incorporating catechol moieties into polymeric backbones. In this work, in order to further investigate the adhesive properties of hydrogels and their potential advantages, several hydrogels based on poly(2-hydroxyethyl methacrylate-co-acrylamide) with N'N-methylene-bisacrylamide (MBA), without/with L-3,4-dihydroxyphenylalanine (DOPA) as a catecholic crosslinker, were prepared via free radical copolymerization. 2-Hydroxyethyl methacrylate (HEMA) and acrylamide (AAm) were used as comonomers and MBA and DOPA both as crosslinking agents at 0.1, 0.3, and 0.5 mol.-%, respectively. The polymeric hydrogels were characterized by Fourier transform infrared spectroscopy (FT-IR), thermal analysis and swelling behavior analysis. Subsequently, the mechanical properties of hydrogels were determined. The elastic properties of the hydrogels were quantified using Young's modulus (stress-strain curves). According to the results herein, the hydrogel with a feed monomer ratio of 1:1 at 0.3 mol.-% of MBA and DOPA displayed the highest rigidity and higher failure shear stress (greater adhesive properties). In addition, the fracture lap shear strength of the biomimetic polymeric hydrogel was eight times higher than the initial one (only containing MBA); however at 0.5 mol.-% MBA/DOPA, it was only two times higher. It is understood that when two polymer surfaces are brought into close contact, physical self-bonding (Van der Waals forces) at the interface may occur in an -OH interaction with wet contacting surfaces. The hydrogels with DOPA provided an enhancement in the flexibility compared to unmodified hydrogels, alongside reduced swelling behavior on the biomimetic hydrogels. This approach expands the possible applications of hydrogels as adhesive materials, in wet conditions, within scaffolds that are commonly used as biomaterials in cartilage tissue engineering.

The longitudinal impact of division-wide implementation of an enhanced recovery after thoracic surgery programme.

OBJECTIVES: Data regarding enhanced recovery after thoracic surgery (ERATS) are sparse and inconsistent. This study aims to evaluate the effects of implementing an enhanced ERATS programme on postoperative outcomes, patient experience and quality of life (QOL). METHODS: We conducted a prospective, longitudinal study evaluating 9 months before (pre-ERATS) and 9 months after (post-ERATS) a 3-month implementation of an ERATS programme in a single academic tertiary care centre. All patients undergoing major thoracic surgeries were included. The primary outcomes included length of stay (LOS), adverse events (AEs), 6-min walk test scores at 4 weeks, 30-day emergency room visits (without admission) and 30-day readmissions. The process-of-care outcomes included time to 'out-of-bed', independent ambulation, successful fluid intake, last chest tube removal and removal of urinary catheter. Perioperative anaesthesia-related outcomes were examined as well as patient experience and QOL scores. RESULTS: The pre-ERATS group (n = 352 patients) and post-ERATS group (n = 352) demonstrated no differences in demographics. Post-ERATS patients had improved LOS (4.7 vs 6.2 days, P < 0.02), 6-min walk test scores (402 vs 371 m, P < 0.05) and 30-day emergency room visits (13.7% vs 21.6%, P = 0.03) with no differences in AEs and 30-day readmissions. Patients experienced shorter mean time to 'out-of-bed', independent ambulation, successful fluid intake, last chest tube removal and urinary catheter removal. There were no differences in postoperative analgesia administration, patient satisfaction and QOL scores. CONCLUSIONS: ERATS implementation was associated with improved LOS, expedited feeding, ambulation and chest tube removal, without increasing AEs or readmissions, while maintaining a high level of patient satisfaction and QOL.

Impact of Adverse Events and Length of Stay on Patient Experience After Lung Cancer Resection.

BACKGROUND: Postoperative adverse events (AEs), prolonged length of stay (PLOS), and patient experience are common quality measures after thoracic surgical procedures. Our objective was to investigate the relationship of postoperative AEs on patient experience and hospital length of stay (LOS) after lung cancer resection. METHODS: AEs (using Thoracic Morbidity and Mortality system based on Clavien-Dindo schema) and LOS were prospectively collected for all patients undergoing lung cancer resection. A 21-item questionnaire, retrospectively asking about patient experience, was mailed to patients twice (October 2015 and January 2016). The impact of AEs on experience was investigated and stratified by hospital LOS, with PLOS defined as the 75th percentile. Univariate analysis used parametric (t test) and nonparametric (Mann-Whitney) tests according to test conditions. RESULTS: Of 288 patients who responded to the survey (70% response rate), 175 (61%) had no AEs, 113 (39%) had experienced at least one AE, and 52 (18%) had experienced PLOS. Lung cancer patients who experienced PLOS showed significantly decreased experience on several questionnaire items, including their impression of comprehensiveness of surgeons information provision during inpatient period (p = 0.008), inpatient recovery from operation (p = 0.001), quality of life 30 days after operation (p = 0.032), follow-up care, (p = 0.022), and satisfaction with outcome 1 year after operation during follow-up care (p = 0.022). The presence of postoperative AEs led only to reduced impression about inpatient recovery from the operation (p = 0.01). CONCLUSIONS: In this cohort, postoperative AEs were minimally associated with negative patient experience. However, patients who experienced PLOS demonstrated a marked reduction in experience after thoracic surgical procedures.

Intrapleural fibrinolytic therapy (IPFT) in loculated pleural effusions--analysis of predictors for failure of therapy and bleeding: a cohort study.

OBJECTIVES: To assess risk factors associated with failure and bleeding in intrapleural fibrinolytic therapy (IPFT) for pleural effusions. DESIGN: Retrospective case series. SETTING: Two tertiary-care centres in North America. PARTICIPANTS: We identified 237 cases that received IPFT for the treatment of pleural effusions. Data for 227 patients were compiled including demographics, investigations, radiological findings pretherapy and post-therapy and outcomes. INTERVENTION: Fibrinolytic therapy in the form of tissue plasminogen activator (t-PA) or streptokinase. PRIMARY AND SECONDARY OUTCOMES: Success of therapy is defined as the presence of both clinical and radiological improvement leading to resolution. Failure was defined as persistence (ie, ineffective treatment) or complications requiring intervention from IPFT. Incidence of bleeding post-IPFT, identifying factors related to failure of therapy and bleeding. RESULTS: IPFT was used in 237 patients with pleural effusions; 163 with empyema/complicated parapneumonic effusions, 32 malignant effusions and 23 with haemothorax. Overall, resolution was achieved in 80% of our cases. Failure occurred in 46 (20%) cases. Multivariate analysis revealed that failure was associated with the presence of pleural thickening (>2 mm) on CT scan (p=0.0031, OR 3, 95% CI 1.46 to 6.57). Bleeding was not associated with any specific variable in our study (antiplatelet medications, p=0.08). CONCLUSIONS: Pleural thickening on a CT scan was found to be associated with failure of IPFT.

Evaluating the reliability and reproducibility of the Ottawa Thoracic Morbidity and Mortality classification system.

BACKGROUND: Minimizing adverse events after surgery is widely recognized as an important indicator of quality; yet no consensus has been reached on how to standardize the reporting of adverse events after surgical procedures. Our objectives were to develop a standardized classification system to monitor both the presence and severity of thoracic morbidity and mortality, and to evaluate its reliability and reproducibility among a national cohort of thoracic surgeons. METHODS: To assess the Thoracic Morbidity and Mortality classification system (based on the Clavien-Dindo classification of adverse events), a 31-item questionnaire was sent to all members of the Canadian Association of Thoracic Surgeons in August 2009, consisting of a general description of the Thoracic Morbidity and Mortality severity grades, 20 case-based questions of postoperative adverse events to be classified, and questions regarding personal judgments. We derived descriptive and quantitative information using weighted Kappa statistics. RESULTS: Fifty-two (54.7%) thoracic surgeons completed the questionnaire; 41 (78.8%) of the respondents were affiliated with an academic teaching hospital. A total of 1,326 individual weighted Kappa statistics were calculated for all distinct pairs of raters, of which 1,152 (87%) were greater than 0.81, a range that is interpreted as "almost perfect agreement." A further 174 (13%) were in the range between 0.61 and 0.8, interpreted as "substantial agreement." All results were statistically significant (p < 0.0001). The classification system was regarded as straightforward (98% of the respondents), reproducible (94%), logical (92%), and useful (98%). CONCLUSIONS: The modified classification system appears to offer objective, reliable, and reproducible reporting of thoracic morbidity and mortality, and thus may assist continuous quality improvement in thoracic surgery.

Systematic classification of morbidity and mortality after thoracic surgery.

BACKGROUND: Objective reporting of postoperative complications is the foundation of surgical quality assurance. We developed a system to identify both presence and severity of thoracic morbidity and mortality, and evaluated its feasibility and utility over the first two years of its implementation. METHODS: The system was based on the Clavien-Dindo classification, in which the severity of a complication is proportional to the effort to treat it. Definitions were developed by peer review and questionnaire. All patients undergoing thoracic surgery (January 2008 to December 2009) were prospectively evaluated. RESULTS: A total of 953 patients (mean age 61 years; range, 14 to 95) underwent thoracic surgery (total # cases 1260), of which 369 patients had at least one complication (29.3% procedures). Grades I and II include minor complications requiring no therapy or pharmacologic intervention only. Grades III and IV are major complications that require surgical intervention or life support. Grade V complications result in patient death. Grades I, II, III, and IV complications comprised 4.9%, 63.9%, 21.1%, and 7.8% of all complications; overall mortality rate (grade V) was 2.2%. The most common complications were prolonged air leak (18.8%) and atrial fibrillation (18.2%) after pulmonary resection, and atrial fibrillation (11.5%) after esophagectomy-gastrectomy. Prolonged air leak led to a major complication (13%), readmission (17%), or prolonged hospital stay (29%) to a greater extent than atrial fibrillation (3%, 2%, and 7%, respectively). CONCLUSIONS: This standardized classification system for identifying presence and severity of thoracic surgical complications is feasible, facilitates objective comparison, identifies burden of illness of individual complications, and provides an effective method for continuous surgical quality assessment.

Radiofrequency ablation for the treatment of non-small cell lung cancer in marginal surgical candidates.

OBJECTIVE: Treatment options for patients with non-small cell lung cancer who are not surgical candidates or who refuse operation are limited. Radiofrequency ablation represents a potential less invasive option for these patients. Our initial experience with radiofrequency ablation for peripheral, primary non-small cell lung cancer is reported. METHODS: We treated 21 tumors in 18 patients. Median age was 75 (range 58-86) years. Cancer stages were I (n = 9), II (n = 2), III (n = 3), and IV (n = 4). Patients with stage IV disease included 3 with recurrence after previous lobectomies and 1 with a synchronous liver metastasis also treated with radiofrequency ablation. Median tumor diameter was 2.8 cm (range 1.2-4.5 cm). Radiofrequency ablation was delivered by minithoracotomy in 2 cases and by a computed tomography-guided percutaneous approach in 16 patients. Computed tomographic and positron emission tomographic scans were used to evaluate recurrence and radiographic response in ablated nodules. RESULTS: One postoperative death occurred from pneumonia after open radiofrequency ablation. Median hospital stay was 2.5 days. A chest tube or pigtail catheter was required in 7 patients (38.9%) for procedure-related pneumothoraces. At a median follow-up of 14 months, 15 patients (83.3%) were alive. Local progression occurred in 8 nodules (38.1%). Mean and median progression-free intervals were 16.8 and 18 months, respectively. For stage I cancers, mean progression-free interval was 17.6 months. Median progression-free interval was not reached. CONCLUSION: This study demonstrates the feasibility of radiofrequency ablation for small, peripheral non-small cell lung cancer tumors. Local control is comparable to, if not better than, that provided by radiotherapy. Radiofrequency ablation should continue to be evaluated by thoracic surgeons as a noninvasive therapy for the high-risk patient with non-small cell lung cancer.