The purpose of this study was to compare structural changes in the pulmonary vasculature in newborns with congenital diaphragmatic hernia (CDH) complicated by persistent pulmonary hypertension (PPH) and stillborns with CDH. Victorian blue van Gieson (VVG) staining and immunostaining with anti-alpha smooth-muscle actin (ASMA) was performed on lung tissue obtained at autopsy from 23 newborns with CDH complicated by PPH, 7 stillborns with CDH, and 11 age-matched controls with sudden infant death syndrome (SIDS). The degrees of adventitial and medial thickness and area were measured in pulmonary arteries with an external diameter (ED) of <75 micrometers, 75-100 micrometers, 100-150 micrometers, 150-250 micrometers, 250-500 micrometers, and >500 micrometers by image analyzer and compared statistically. The degrees of adventitial and medial thickness and area were measured in pulmonary veins with an ED of <100 micrometers, 100-200 micrometers, and >200 micrometers by image analyzer and compared statistically. In order to determine whether the characteristic structural changes were size-related, each was related to ED. There was a significant increase in adventitial thickness and area in arteries of all sizes in both newborns and stillborns with CDH compared to SIDS patients (P < 0. 05). The degree of medial thickness in newborns and stillborns with CDH was significantly increased compared to SIDS patients (P < 0.01). The degree of medial area was significantly increased for arteries with ED less than 100 micrometers (P < 0.05) in newborns and stillborns with CDH compared with SIDS patients. There was a significant increase in adventitial thickness and area in veins of all sizes in newborns with CDH compared to stillborns with CDH and SIDS (P < 0. 05). The degree of adventitial thickness and area of pulmonary veins were similar in stillborns with CDH and SIDS. There were no significant differences in medial thickness of veins between the three groups. The presence of abnormally thick-walled pulmonary arteries in stillborns with CDH suggests that the intrapulmonary arteries in CDH may become excessively muscularized during fetal life, becoming unable to adapt normally at birth. The absence of structural changes in pulmonary veins in stillborns with CDH suggests that the pulmonary venous changes observed in newborns with CDH complicated by PPH occur after birth as a result of increases in transvascular pressure or a response to release of peptide growth factors.
BackgroundLaparoscopic percutaneous extraperitoneal closure (LPEC) has become a common procedure for repairing inguinal hernia. As a laparoscopic approach, pediatric surgical trainees require more training to learn LPEC than a traditional open approach. This study aimed to clarify the experience needed to acquire the skill to perform LPEC adequately.MethodsThis descriptive single-center study used clinical data from patients who underwent LPEC between May 2009 and May 2016. The mean operative time for ten consecutive unilateral repairs was used as an index of proficiency with the procedure. The number of repairs performed before the mean operative time became less than 20 min was evaluated for each trainee.ResultsDuring the study period, six pediatric surgical trainees participated in the training independently. The number of the patients was 987. The total number of repairs was 1436, including 538 unilateral repairs and 449 concurrent bilateral repairs. Overall, the mean operative time was 21.8 ± 8.1 min for unilateral repair and 31.4 ± 9.7 min for concurrent bilateral repairs. The mean number of repairs performed before the acquisition of skill for dexterous LPEC was 125.1 ± 29.5.ConclusionsAlthough there were individual differences, all trainees acquired the skill to perform LPEC adequately within one year. With appropriate guidance, LPEC can become a standard technique for pediatric surgical trainees, along with traditional open surgery. These results provide valuable information for planning LPEC training.
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