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There is a paucity of level 1 and level 2 evidence for best practice in surgical management of CDH. Antenatal imaging and prognostication is developing. Observed to expected lung-to-head ratio on ultrasound allows better predictive value over simple lung-to-head ratio. Based on 2 randomised studies, the verdict is still out in terms the best group and indication for antenatal intervention and their outcome. Tracheal occlusion is best suited for prospective randomised studies of benefit and outcome. Only one pilot randomised controlled study of thoracoscopic repair exists, suggesting increased acidosis; blood gases and CO 2 levels should be closely monitored. Only poorly controlled retrospective studies suggest higher recurrence rates. Randomised studies on the outcome of thoracoscopic repair are needed. Careful selection, anaesthetic vigilance, monitoring and follow-up of these cases are required. There is no evidence to suggest the best patch material to decrease recurrences. Evidence suggests no benefit from routine fundoplication based on the one randomised study. Multi-disciplinary follow-up is required. This can be visits to different specialities, but may be best served by a multi-disciplinary one-stop clinic. [ABSTRACT FROM AUTHOR]

OBJECTIVES To analyse the long-term outcomes of aortic valve (AV) repair with biological patch in patient with non-rheumatic valve disease. METHODS From 1995 to 2011, 554 patients underwent elective (AV) repair; among them, 57 (mean age 45 ± 17 years) had cusp restoration using patch for non-rheumatic valve disease. Seven (12%) patients had unicuspid valve, 30 (53%) patients had bicuspid valve and 20 (35%) had tricuspid valve. Autologous pericardium was used in 26 patients (7 treated, 19 non-treated), bovine pericardium in 26, autologous tricuspid valve leaflet in 4 and aortic homograft cusp in 1. Patching was used to repair perforation (n = 20, 35%), commissural defect (n = 18, 32%), raphe repair (n = 17, 30%) or for cusp extension (n = 2, 3.5%). Echocardiographic and clinical follow-up was 98% complete and mean follow-up was 72 ± 42.5 months. RESULTS No hospital mortality. At 8 years, overall survival was 90 ± 5% and freedom from valve-related death was 96 ± 3%. Two patients (3.5%) needed early reoperation for aortic regurgitation (AR); they underwent re-repair and the Ross procedure, respectively. Late reoperation was necessary in 9 patients (16%) for AR (n = 4), stenosis (n = 3) or mixed disease (n = 2). They had the Ross procedure (n = 6) or prosthetic valve replacement (n = 3) with no mortality. At 8 years, freedom from reoperation was 75 ± 9%. Freedom from reoperation was slightly higher in tricuspid compared with non-tricuspid valves (92 ± 7 vs 68 ± 11%, P = 0.18) and slightly higher for bovine (95 ± 5%) compared with autologous pericardium (73 ± 11%, P = 0.38), but differences were statistically not significant. In tricuspid valves, freedom from reoperation was higher in perforation repair compared with other techniques (100 vs 50 ± 35%, P = 0.02). In bicuspid valves, freedom from reoperation was similar between different repair techniques (P = 0.38). Late echocardiography showed AR 0-1 in 30 (53%) patients, AR 2 in 12 (21%) and no AR ≥ 3. Three patients presented a mean transvalvular gradient of 30–40 mmHg. Thromboembolic events occurred in 2 patients (0.6%/patient-year), bleeding events in 1 (0.3% /patient-year) and no endocarditis occurred. CONCLUSIONS AV repair with biological patch is feasible for various aetiologies. The techniques are safe and medium-term durability is acceptable, even excellent for perforation repair in tricuspid valve morphology. Bovine pericardium is a good alternative to autologous pericardium. [ABSTRACT FROM AUTHOR]

An experimental investigation was conducted to evaluate the structural behavior and chloride penetration characteristic of reinforced concrete columns to which patch repair was applied. A total of 24 reinforced concrete columns were fabricated. Four repair materials, with different types and contents of admixtures, were selected. The contents of the three admixtures (silica fume, zeolite, and polymer dispersion) were 0%, 10%, and 15%, based on the weights of the admixture and cement. For the experimental methods, a chloride penetration test and an axial compression test were used. As a result of the experiments, compression failure occurred in the control column. For the repaired columns, however, interfacial failure was observed, as the concrete core and repair material were debonded. The repair material that showed the greatest effect was mortar, for which polymer dispersion was used as the admixture. The ultimate strength and the strain at ultimate strength of the column that was repaired with this mortar increased by 40% and 80%, respectively, compared to the control column. Furthermore, the repair mortars that were mixed with the admixture showed much lower chloride concentrations than the control column. In particular, the chloride concentration of the mortar that was mixed with 15% polymer dispersion decreased by 95%, in the section with a depth of 20–30 mm from the column surface. [ABSTRACT FROM AUTHOR]

Experiments and finite element analysis (FEA) were performed on scarf-patch repaired composite panels. Tensile static tests were performed on pristine and repaired panels to evaluate their tensile strength. The obtained results showed that the repaired panels restored tensile strength by 95% of the pristine value. Subsequently, a verification finite element (FE) model was established. Two additional models, one with homogenized mechanical properties of the laminate and one that considered that the ply-by-ply properties were built to simulate the experimental repairs. The predictions of the two models agreed reasonably well with the experimental results and the optimum scarf angle was found at 2.5°. [ABSTRACT FROM PUBLISHER]

• The effectiveness of bio-based repair materials was presented and highlighted. • The resistance against ingress of water was enhanced by alginate-based healing agents. • Re-deterioration in patch repair method was prevented by the use of Bacillus subtilis (natto). • The use of Bacillus subtilis (natto) was proved to work as a cathodic inhibitor. This study explored the application of bio-based repair materials to concrete for crack repair and patch repair methods. First, the concept of crack repair using Bacillus subtilis (natto) under wet conditions is presented. In addition to the self-healing efficiency, enhancement of corrosion resistance owing to consumption of dissolved oxygen by bacteria which could work as a cathodic inhibitor is theoretically explained by electro-chemical reactions. And then, this study exemplified the application of the bio-based repair material to concrete with respect to crack repair and patch repair methods. First, alginate-based self-healing materials (in-situ encapsulation) are newly developed in this study to improve the resistance against ingress of water in cracked mortar specimens, which is demonstrated by the reduced absorption of water. This is adequately explained by the fact that the calcite precipitation in gel films formed in crack is highly effective in sealing crack in mortar specimen. In addition, the healing agents could reduce the concentration of dissolved oxygen in concrete, which is found to contribute to reduction of the macrocell corrosion current density in which the corrosion rate is determined by the cathodic reactions associated with diffusion of dissolved oxygen. The use of Bacillus subtilis (natto) is highly advantageous in preventing re-deterioration owing to macrocell corrosion taking place between patch repair region and surrounding concrete containing chloride. [ABSTRACT FROM AUTHOR]

This paper aimed at an experimental investigation of the comparative corrosion phenomenon in the reinforcing steel of repaired chloride contaminated self-compacting concrete (SCRC) and ordinary concrete (OC) patches. This research is a continuation of a previous study in which macrocell specimens were prepared with OC having different chloride contaminations simulating the actual patch repair in the construction field. Here, in this research, the same specimens were prepared with SCRC to investigate more deeply the macrocell phenomenon in SCRC, which received limited attention in the past. Four prismatic specimens with two sets of 5 and 3% chloride contaminated SCRC at the two ends were prepared respectively, and the middle portion of these specimens was cast after 24 h with uncontaminated SCRC simulating the actual patch repair in the field. After 1 year of experimental observations of corrosion potentials and corrosion rates, interesting and novel results were obtained in comparison with OC and SCRC specimens. [ABSTRACT FROM AUTHOR]

OBJECTIVES Different surgical strategies have been evolved for the surgical treatment of ruptured sinus of Valsalva aneurysm (RSVA) from simple primary closure to patching of the rupture site by a dual chamber approach. We reviewed our 25-year experience and current literature regarding the efficacy of different surgical approaches. METHODS A retrospective review identified 55 patients who underwent RSVA repair between 1985 and 2011. The mean age was 30.9 ± 12.1 years. The RSVA originated from the right coronary sinus in 43 patients (78.2%), from the non-coronary sinus in 11 (20.0%) and from the left in 1. Rupture into the right ventricle was the most common result (n = 38). Dual-chamber exposure (the involved chamber and aorta) was used in 67.3% of the patients and isolated trans-aortic approach was used in 32.7%. RSVA was repaired with either a patch (n = 43) or direct sutures (n = 12), whereas the aortic valve was replaced in eight patients among the last group. RESULTS The hospital mortality rate was 3.6%. The follow-up was available in 94.3% (50 patients) of survivors ranging from 1 month to 25 years (mean 15.3 ± 4.1 years). There were five late deaths. Recurrence of the fistula was seen in two primarily repaired (two of four patients) and none of the patched-closed patients. Actual survival was 93.4 ± 3.7% at 10 years and 87.1 ± 5.6% at 15 years. Freedom from reoperations was 81.6 ± 6.1% at 15 years. CONCLUSIONS Surgical treatment for RSVA carries an acceptably low operative risk and long-term freedom from death and reoperation. Surgical approach must be chosen according to the ruptured chamber and associated lesions. Patch repair of RSVA must be preferred. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a patch repair method that uses high performance fiber reinforced cement composites (HPFRCCs) to repair reinforced concrete members damaged by chloride attack. The beam specimens were deteriorated under chloride attack and then repaired using HPFRCC shotcreting, before they were loaded to investigate their mechanical performance. The experimental results indicates that even after formation of multiple fine cracks under applied load, the HPFRCC remains impermeable due to its very small crack width. With the proposed repair method, the HPFRCC patch layer allowed only very fine cracks to be formed in service conditions. The strength of a beam deteriorated by rebar corrosion could be recovered using HPFRCC patching if the amount of corrosion was less than 10%. It was also clarified that a combined use of a fiber net with HPFRCC patching improves the dispersibility of fine cracks in the HPFRCC layer. [Copyright &y& Elsevier]

Congenital diaphragmatic hernia is a rare but severe condition affecting 1 in 2000 to 3000 newborns with a survival rate of 67%. Although regular antenatal screening allows prenatal diagnosis in many cases, traditionally treatment has been based on postnatal surgical repair. Recent literature has pointed out the survival benefits of initial stabilization and the use of gentle ventilation strategies prior to definitive treatment, shifting the trend from immediate to delayed surgical repair. Advances in fetal intervention have allowed the introduction of fetal endoscopic tracheal occlusion as a method to hasten lung development before birth in order to minimize postnatal morbidity. Despite appropriate treatment, the long-term outcomes of these patients are plagued with numerous complications, associated with the primary pathology and also aggressive therapeutic measures. International centers of excellence have recently come together in an effort to standardize the care of such patients in hopes of maximizing their outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Infrastructure rehabilitation represents a multitrillion dollar opportunity for the construction industry. In USA alone the rehabilitation needs are estimated to exceed 1.6 trillion dollars over the next 5years. Since the majority of the existent infrastructures are concrete based this means that concrete infrastructure rehabilitation is a hot issue to be dealt with. Besides the sooner concrete deterioration is tackled the lower are the rehabilitation costs. This paper provides a literature review on concrete repair materials, highlighting the current problems face by them. It covers concrete surface treatments, patch repair and FRP strengthening. The case of trenchless rehabilitation of concrete sewage pipelines is also discussed. The potential of geopolymers to overcome those limitations is analyzed. [Copyright &y& Elsevier]

Abstract: Background: Large congenital diaphragmatic hernia (CDH) defects often require the use of synthetic patches for tension-free repair. Although high rates of recurrence and other morbidities have been previously reported, our favorable perception of patch repair prompted this review. Methods: A single-center retrospective chart review of CDH cases repaired between January 1, 1999, and October 1, 2010. Patch repairs were performed by multiple surgeons with an effort to construct a tension-free dome-shaped patch. Results: One hundred eighty-four children underwent CDH repair of whom 99 (53.8%) required a patch. Seventy-four (74.7%) of the 99 patients who underwent patch repair survived to discharge and were compared with 75 primary repair survivors. Of those undergoing patch repair, 88% were prenatally diagnosed, 55% had liver herniation, and 22 (29.9%) were repaired on extracorporeal membrane oxygenation. Two patients experienced a recurrence after a patch repair and 3 after a primary repair for a rate of 5.4% and 4.0%, respectively (P = 1.0). Conclusions: These results demonstrate that synthetic patch repair for CDH can be performed with a very low rate of recurrence challenging the need for alternative approaches to diaphragmatic replacement. High rates of recurrence reported for patch repair may be technical rather than intrinsic to the patch. [Copyright &y& Elsevier]

Abstract: Patch repairs are common in the rehabilitation of reinforced concrete structures, mainly bridges but also buildings, exposed to carbonation and chloride ingress. This technique includes the following steps: (i) removal of damaged concrete; (ii) cleansing of corroded steel rebars; (iii) application of anti-corrosive coating; and (iv) application of a repair mortar. Although the application of an anti-corrosive coating is common practice, part of most manufacturers’ guidelines and, moreover, a mandatory step in some countries standards, it is important to assess if it decreases the bond of steel rebars to the repair mortar, in which case the anti-corrosive protection of the rebars should be assured in an alternative way. The experimental study herein described includes 72 pull-out tests and it was conducted aiming to characterise the bond strength of the rebar-to-mortar interface and, subsequently, to define the most adequate procedure concerning the anti-corrosive protection of the rebars. In summary, it can be stated that it is advisable to always apply cementitious coatings to plain rebars whereas it should be avoided for ribbed rebars since, in this case, the loss of average bond strength due to coatings can reach 40%. [Copyright &y& Elsevier]

The tension-softening parameters for different concrete-concrete interfaces are determined using the bimaterial cracked hinge model. Beams of different sizes having a jointed interface between two different strengths of concrete are tested under three-point bending (TPB). The load versus crack mouth opening displacement (CMOD) results are used to obtain the stress-crack opening relation through an inverse analysis. In addition, the fracture energy, tensile strength, and modulus of elasticity are also computed from the inverse analysis. The fracture properties are used in the nonlinear fracture mechanics analysis of a concrete patch-repaired beam to determine its load-carrying capacity when repaired with concrete of different strengths. [ABSTRACT FROM AUTHOR]