The burst strength is one of the most important characteristics for nonwovens. The strength of three kinds of the nonwoven were detected under four testing radius, including the wood spunlace nonwoven, the Spunbond-Meltblown-Spunbond (SMS) nonwoven and the melt nonwoven. The precise results of the SMS and the melt nonwoven could be received by removing the influence of the elastic membrane and the single-peak fitting. The influence of the testing radius to the strength results was also studied, and the semiempirical formula (q0=k/r3) was deduced using the elastic mechanics theory and testing data.
ObjectiveTo summarize clinical results and experience of subarterial ventricular septal defect (sVSD) closure through a minimal right vertical infra-axillary incision in children, and evaluate the feasibility of this technique. MethodsClinical data of 27 sVSD patients who underwent surgical repair through a minimal right vertical infra-axillary incision from March 2009 to January of 2013 in the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed. There were 20 male and 7 female patients with their age of 1.1-11.0 (4.4±2.8) years and body weight of 7.6-28.0 (14.6±5.3) kg. After induction of anesthesia, the patients were placed in a 90 degree left lateral position. The incision was performed along right midaxillary line vertically between the superior border of the third rib and inferior border of the fifth rib. The thoracic cavity was entered through the fourth intercostal space. The pericardium was opened 2 cm anterior to the phrenic nerve and suspended to elevate the heart and great vessels by the pericardial traction sutures. Cardiopulmonary bypass (CPB) was established after cannulation of the ascending aorta, superior vena cava and inferior vena cava. Closure of sVSD was performed through longitudinal pulmonary incision. After procedures under CPB finished, the aortic cannula was removed and the pericardium was closed with interrupted sutures. The thoracic drainage tube was placed through the sixth intercostal space. All the patients were followed up 3, 6 and/or 12 months after surgery. Satisfactory degree of the patients and their relatives were evaluated. Chest X-ray, electrocardiography and echocardiography were examined. ResultsSurgical repair of sVSD was performed in all the patients through this incision without any difficulty, incision prolongation or conversion to another incision. There was no in-hospital death, reexploration for bleeding, postoperative atelectasis, pulmonary infection, pleural effusion, impairment of central nervous system, phrenic nerve damage, poor wound healing, wound infection or pericardial effusion. Incision length was 4.4-7.0 (5.07±0.66) cm. Echocardiography before discharge showed no residual shunt in all the patients. All the patients were followed up 3, 6 and/or 12 months at the outpatient department or via the phone. During follow-up, there was no late death, residual shunt or chest asymmetry. The short incision under the armpit was obscured and provided favorable cosmetic results. All the patients and their relatives were satisfied with the cosmetic results. ConclusionRepair of sVSD through a minimal right vertical infra-axillary incision is feasible and safe for children. The advantages of this technique are favorable for children with sVSD.