Optical Trocar Access for Retroperitoneal Robotic-Assisted Pyeloplasty in Children with Ureteropelvic Junction Obstruction.

Purpose: Retroperitoneal robotic-assisted pyeloplasty (ret-RAP) for ureteropelvic junction obstruction (UPJO) requires a larger retroperitoneal space (RS) to maintain specified distances between robotic (da Vinci) trocars and between trocars and the region of interest. A modified closed technique (MOT) and conventional closed technique (COT) were compared for creating an adequate RS with optical trocars. Methods: RS access in children with UPJO who underwent ret-RAP (n = 30) was MOT (n = 15) and COT (n = 15). All patients were positioned laterally. For MOT, a 5 mm optical trocar was inserted at the angle formed between the 12th rib and the erector spinae muscles. As the trocar was advanced under direct vision, it pierced the superficial subcutaneous layer, Scarpa's fascia, lumbar fascia, internal/external oblique and transversus abdominalis muscles, and the posterior renal fascia. Once in the RS, the tip of the scope was used for blunt dissection of perirenal fat, the tip was withdrawn until it was outside the perirenal fascia, and used to dissect toward the anterior abdomen in the pararenal fat layer. Results: Ages and weights at ret-RAP were similar (MOT: 5.6 ± 1.8 years versus COT: 7.8 ± 4.6 years; MOT: 20.6 ± 10.1 kg versus COT: 27.6 ± 13.9 kg). Times for RS access were similar (MOT: 1.6 ± 0.5 minutes versus COT: 1.9 ± 0.7 minutes), but RS expansion was significantly quicker in MOT (32.3 ± 8.7 minutes versus 52.0 ± 15.1 minutes; P < .001). Peritoneal injury caused carbon dioxide leakage in 4 of 15 COT cases and 0 of 15 MOT cases. Conclusion: RS expansion with MOT was safer because there were no peritoneal injuries and MOT was quicker than COT.

The outcome of closure of inguinal hernia with laparoscopic percutaneous extraperitoneal closure in young adults.

BACKGROUND: Hernioplasty is one of the most commonly performed surgeries. However, the optimal procedure for young adults has not been defined yet. Our study compared the outcomes of laparoscopic percutaneous extraperitoneal closure (LPEC) in young adults with outcomes in children. MATERIAL AND METHODS: We retrospectively reviewed patients aged 0-30 years who underwent LPEC. Data regarding age, sex, hernia type, surgical time, pre-intraoperative laterality, contralateral patent processus vaginalis (CPPV), and complications were analyzed. RESULTS: LPEC was performed on 2642 patients in our hospital. Of these, 51 patients were young adults (aged 15-30 years). Asymptomatic CPPV in unilateral patients was frequent in the <15-year age group (50.2%) compared to the 15-30-year age group (15.9%). The median surgical time was shorter in the <15-year age group (19 min, interquartile range [IQR]: 24-33) compared to that of the 15-30-year age group (33 min, IQR: 23.3-40.8). CONCLUSIONS: This is the first report on the outcomes in young adult patients who underwent LPEC. The median surgical time was longer in the 15-30-year age group than in the <15-year age group. The median follow-up was 4.7 years with no intra-postoperative complications, such as postoperative bleeding, infection, persistent pain, and recurrence. LPEC is an effective, cosmetic, and safe surgical treatment in young adults and children.

A Pilot Study to Determine the Role of Spatulating the Ureter During Pyeloplasty in Children for Ureteropelvic Junction Obstruction in the Robotic Era.

Purpose: Spatulation during ureteropelvic junction obstruction repair was evaluated in children treated by robot-assisted retroperitoneal pyeloplasty anastomosis (RRPA). Methods: Intraoperative video recordings (IVRs) of RRPA (n = 22 ureters) performed at a single institute between 2018 and 2022 were reviewed blindly by 5 independent surgeons for perceived difficulty of suturing (DOS; 5 = impossible; 4 = difficult; 3 = tedious; 2 = slow; 1 = easy) and spatulation ranking as superior (+1), inferior (-1), or unnecessary (0). The retroperitoneal space was accessed in the lateral decubitus position using a closed technique under direct vision to avoid air leakage and subcutaneous emphysema. All subjects had a Double-J stent (4.7F) placed. Results: Subjects had similar demographics and preoperative ureter diameters. IVRs were RRPA with spatulation of the ureter on the lateral side (RRPA +SP) (n = 13) and RRPA without spatulation of the ureter (RRPA -SP) (n = 9). Overall DOS scores and coefficients of variation for time taken to place one suture were similar. Total anastomotic time was significantly shorter for RRPA -SP; 67.9 ± 8.4 minutes versus 57.9 ± 9.2 minutes, P = .01. Overall spatulation ranking was 0. Postoperative scanning showed improved drainage in 12 of 13 (92%) in RRPA +SP and 8 of 9 (88%) in RRPA -SP; differences were not significant. One anastomotic stricture in RRPA -SP required open repair. Conclusions: RRPA was quicker and more precise without spatulation. Outcomes of scanning 1 year after RRPA were similar for RRPA -SP and RRPA +SP.

Prednisolone administration monitored by postoperative stool color achieves high jaundice clearance after laparoscopic portoenterostomy for biliary atresia.

PURPOSE: Stool color (SC) for monitoring prednisolone use in biliary atresia (BA) patients after laparoscopic portoenterostomy (LPE) was reviewed. METHODS: Subjects were 47 post-LPE BA patients given a reducing dose course of intravenous prednisolone. The course started at 4 mg/kg/day and gradually reduced, ultimately reaching a final total dose (TD) of 31.5 mg/kg. Normal SC indicated a course could progress until finished and was repeated until jaundice clearance (JC) was achieved. Abnormal SC persisting for two consecutive courses was the absolute indication for redo or liver transplantation (LTx). RESULTS: JC was achieved in 38/47 (80.9%) LPE cases and 4/6 redos to give an overall JC rate (JCR) of 42/47 (89.4%). Outcomes after one course (n = 5; JCR: 80.0%; median TD: 30.0 mg/kg, interquartile range [IQR: 26.0-31.5]), two courses (n = 10; JCR: 90.0%; median TD: 62.5 mg/kg [IQR: 60.8-66.0]), three courses (n = 13; JCR: 92.3%; median TD: 90.0 mg/kg [IQR: 86.0-90.0]), four courses (n = 10; JCR: 80.0%; median TD: 120.0 mg/kg [IQR: 116.7-123.3]), five courses (n = 7; JCR: 100%; median TD: 156.0 mg/kg [IQR: 154.3-157.5]), six courses (n = 1; JCR: 100%; TD: 189.0 mg/kg), ten courses (n = 1; JCR: 100%; TD: 308 mg/kg). CONCLUSION: Indications for repeat prednisolone and timing of redo/LTx based on SC monitoring appeared effective based on high JCR and successful redo/LTx. LEVELS OF EVIDENCE: III.

Lung viral infection modelling in a bioengineered whole-organ.

Lung infections are one of the leading causes of death worldwide, and this situation has been exacerbated by the emergence of COVID-19. Pre-clinical modelling of viral infections has relied on cell cultures that lack 3D structure and the context of lung extracellular matrices. Here, we propose a bioreactor-based, whole-organ lung model of viral infection. The bioreactor takes advantage of an automated system to achieve efficient decellularization of a whole rat lung, and recellularization of the scaffold using primary human bronchial cells. Automatization allowed for the dynamic culture of airway epithelial cells in a breathing-mimicking setup that led to an even distribution of lung epithelial cells throughout the distal regions. In the sealed bioreactor system, we demonstrate proof-of-concept for viral infection within the epithelialized lung by infecting primary human airway epithelial cells and subsequently injecting neutrophils. Moreover, to assess the possibility of drug screening in this model, we demonstrate the efficacy of the broad-spectrum antiviral remdesivir. This whole-organ scale lung infection model represents a step towards modelling viral infection of human cells in a 3D context, providing a powerful tool to investigate the mechanisms of the early stages of pathogenic infections and the development of effective treatment strategies for respiratory diseases.

Hydrogel-in-hydrogel live bioprinting for guidance and control of organoids and organotypic cultures.

Three-dimensional hydrogel-based organ-like cultures can be applied to study development, regeneration, and disease in vitro. However, the control of engineered hydrogel composition, mechanical properties and geometrical constraints tends to be restricted to the initial time of fabrication. Modulation of hydrogel characteristics over time and according to culture evolution is often not possible. Here, we overcome these limitations by developing a hydrogel-in-hydrogel live bioprinting approach that enables the dynamic fabrication of instructive hydrogel elements within pre-existing hydrogel-based organ-like cultures. This can be achieved by crosslinking photosensitive hydrogels via two-photon absorption at any time during culture. We show that instructive hydrogels guide neural axon directionality in growing organotypic spinal cords, and that hydrogel geometry and mechanical properties control differential cell migration in developing cancer organoids. Finally, we show that hydrogel constraints promote cell polarity in liver organoids, guide small intestinal organoid morphogenesis and control lung tip bifurcation according to the hydrogel composition and shape.

Lessons learned from pre-clinical testing of xenogeneic decellularized esophagi in a rabbit model.

Decellularization of esophagi from several species for tissue engineering is well described, but successful implantation in animal models of esophageal replacement has been challenging. The purpose of this study was to assess feasibility and applicability of esophageal replacement using decellularized porcine esophageal scaffolds in a new pre-clinical model. Following surgical replacement in rabbits with a vascularizing muscle flap, we observed successful anastomoses of decellularized scaffolds, cues of early neovascularization, and prevention of luminal collapse by the use of biodegradable stents. However, despite the success of the surgical procedure, the long-term survival was limited by the fragility of the animal model. Our results indicate that transplantation of a decellularized porcine scaffold is possible and vascular flaps may be useful to provide a vascular supply, but long-term outcomes require further pre-clinical testing in a different large animal model.

Biochemical Evaluation of Laparoscopic Portoenterostomy for Treating Biliary Atresia and Redo for Failed Portoenterostomy.

Background: Postoperative outcomes of portoenterostomy (PE) and redo-PE were evaluated using selected biochemical markers (SBM) and biochemical status categories (BSC). Methods: Subjects were 70 consecutive PE performed for biliary atresia. SBM were aspartate aminotransferase (AST)/alanine aminotransferase (ALT), cholinesterase (ChE), and platelet count (PLT) assessed at 1, 2, 3, 6, and 12 months, and thence, annually for a maximum of 10 years. BSC were as follows: all SBM normal (N-SBM), normal AST/ALT (N-SLT), normal ChE (N-ChE), normal PC (N-PLT), all abnormal (A-SBM), abnormal AST/ALT (A-SLT), abnormal ChE (A-ChE), and abnormal PC (A-PLT). Subjects achieving jaundice clearance (JC) and surviving with native livers (SNL) also had gamma glutamyl transpeptidase assessed. Redo-PE indicated for failed PE was assessed postoperatively using the same SBM/BSC protocol. Results: PE were laparoscopic (LPE; n = 40) or open (OPE; n = 30). Mean age/weight at PE and duration of follow-up were similar. For JC, LPE = 34/40 (85.0%) and OPE = 22/30 (73.3%); P = .23. For SNL, LPE = 29/40 (72.5%) and OPE = 16/30 (53.3%); P = .10. LPE and OPE were similar for SBM/BSC, except for a single significant increase in ALT in OPE at 6 months. Redo-PE was performed 17-180 days (mean 67.1 days) after primary PE. AST was significantly increased at the last preredo assessment 3 months after primary PE; P < .05. After redo, AST decreased and SBM/BSC results were equivalent to nonredo subjects. Conclusion: Postoperative biochemical data for all PE cases were comparable; redo-PE would appear to be viable for restoring SBM, and AST could be valuable as a single marker of deterioration in redo cases.

Regenerative medicine for childhood gastrointestinal diseases.

Several paediatric gastrointestinal diseases result in life-shortening organ failure. For many of these conditions, current therapeutic options are suboptimal and may not offer a cure. Regenerative medicine is an inter-disciplinary field involving biologists, engineers, and clinicians that aims to produce cell and tissue-based therapies to overcome organ failure. Exciting advances in stem cell biology, materials science, and bioengineering bring engineered gastrointestinal cell and tissue therapies to the verge of clinical trial. In this review, we summarise the requirements for bioengineered therapies, the possible sources of the various cellular and non-cellular components, and the progress towards clinical translation of oesophageal and intestinal tissue engineering to date.

Mitochondrial fission links ECM mechanotransduction to metabolic redox homeostasis and metastatic chemotherapy resistance.

Metastatic breast cancer cells disseminate to organs with a soft microenvironment. Whether and how the mechanical properties of the local tissue influence their response to treatment remains unclear. Here we found that a soft extracellular matrix empowers redox homeostasis. Cells cultured on a soft extracellular matrix display increased peri-mitochondrial F-actin, promoted by Spire1C and Arp2/3 nucleation factors, and increased DRP1- and MIEF1/2-dependent mitochondrial fission. Changes in mitochondrial dynamics lead to increased production of mitochondrial reactive oxygen species and activate the NRF2 antioxidant transcriptional response, including increased cystine uptake and glutathione metabolism. This retrograde response endows cells with resistance to oxidative stress and reactive oxygen species-dependent chemotherapy drugs. This is relevant in a mouse model of metastatic breast cancer cells dormant in the lung soft tissue, where inhibition of DRP1 and NRF2 restored cisplatin sensitivity and prevented disseminated cancer-cell awakening. We propose that targeting this mitochondrial dynamics- and redox-based mechanotransduction pathway could open avenues to prevent metastatic relapse.

Monitoring tissue engineered constructs and protocols with laboratory-based x-ray phase contrast tomography.

Tissue engineering (TE) aims to generate bioengineered constructs which can offer a surgical treatment for many conditions involving tissue or organ loss. Construct generation must be guided by suitable assessment tools. However, most current tools (e.g. histology) are destructive, which restricts evaluation to a single-2D anatomical plane, and has no potential for assessing constructs prior to or following their implantation. An alternative can be provided by laboratory-based x-ray phase contrast computed tomography (PC-CT), which enables the extraction of 3D density maps of an organ's anatomy. In this work, we developed a semi-automated image processing pipeline dedicated to the analysis of PC-CT slices of oesophageal constructs. Visual and quantitative (density and morphological) information is extracted on a volumetric basis, enabling a comprehensive evaluation of the regenerated constructs. We believe the presented tools can enable the successful regeneration of patient-specific oesophagus, and bring comparable benefit to a wide range of TE applications. STATEMENT OF SIGNIFICANCE: Phase contrast computed tomography (PC-CT) is an imaging modality which generates high resolution volumetric density maps of biological tissue. In this work, we demonstrate the use of PC-CT as a new tool for guiding the progression of an oesophageal tissue engineering (TE) protocol. Specifically, we developed a semi-automated image-processing pipeline which analyses the oesophageal PC-CT slices, extracting visual and quantitative (density and morphological) information. This information was proven key for performing a comprehensive evaluation of the regenerated constructs, and cannot be obtained through existing assessment tools primarily due to their destructive nature (e.g. histology). This work paves the way for using PC-CT in a wide range of TE applications which can be pivotal for unlocking the potential of this field.

Local and systemic responses to SARS-CoV-2 infection in children and adults.

It is not fully understood why COVID-19 is typically milder in children1-3. Here, to examine the differences between children and adults in their response to SARS-CoV-2 infection, we analysed paediatric and adult patients with COVID-19 as well as healthy control individuals (total n = 93) using single-cell multi-omic profiling of matched nasal, tracheal, bronchial and blood samples. In the airways of healthy paediatric individuals, we observed cells that were already in an interferon-activated state, which after SARS-CoV-2 infection was further induced especially in airway immune cells. We postulate that higher paediatric innate interferon responses restrict viral replication and disease progression. The systemic response in children was characterized by increases in naive lymphocytes and a depletion of natural killer cells, whereas, in adults, cytotoxic T cells and interferon-stimulated subpopulations were significantly increased. We provide evidence that dendritic cells initiate interferon signalling in early infection, and identify epithelial cell states associated with COVID-19 and age. Our matching nasal and blood data show a strong interferon response in the airways with the induction of systemic interferon-stimulated populations, which were substantially reduced in paediatric patients. Together, we provide several mechanisms that explain the milder clinical syndrome observed in children.

Comparison of surgical outcomes between laparoscopic percutaneous extracorporeal closure (LPEC) and open repair for pediatric inguinal hernia by propensity score methods and log-rank test analysis.

BACKGROUND: Despite a number of studies comparing laparoscopic inguinal hernia repair (LH) and open herniorrhaphy (OH), the putative advantage of LH remains controversial due to a paucity of firm evidence. We hypothesized that LH has both advantages and disadvantages compared to OH and sought to clarify them by comprehensively analyzing the retrospective data using the combination of multiple statistical methods. METHODS: Operative data for inguinal hernia during the period from February 1999 to December 2019 were examined. The patients were assigned into two groups according to the surgical procedure: laparoscopic percutaneous extraperitoneal closure (LPEC, n = 2410) and OH (n = 2038). Operative and anesthesia times and incidence of postoperative complications were evaluated using the propensity score methods and log-rank test. RESULTS: In comparison with OH, operative time of LPEC was longer for unilateral repair (21.59 ± 8.1 min vs 18.01 ± 8.0 min; p < 0.001) and shorter for bilateral repairs (28.55 ± 10.1 min vs 33.23 ± 11.7 min; p < 0.001), while anesthesia times were longer for both unilateral repair (57.67 ± 10.1 min vs 40.62 ± 11.9 min; p < 0.001) and bilateral repairs (65.95 ± 12.5 min vs 56.35 ± 15.1 min; p < 0.001). LPEC significantly reduced the risk of metachronous contralateral hernia (MCLH) (0.52% vs 9.29%; p < 0.001), but the recurrence rate was higher (0.21% vs 0.04%; p = 0.002) than OH. Orchiectomy due to testicular atrophy or torsion was required in 3 cases of OH (0.19%), whereas it was not seen in LPEC. CONCLUSIONS: LPEC had a less risk of MCLH and testicular complications but was associated with a higher recurrence rate and longer anesthesia time. Propensity scoring techniques can enhance the robustness of retrospective comparisons between groups over several years of data collection, which is frequently required in pediatric surgery studies.

In vitro models of fetal lung development to enhance research into congenital lung diseases.

PURPOSE: This paper aims to build upon previous work to definitively establish in vitro models of murine pseudoglandular stage lung development. These can be easily translated to human fetal lung samples to allow the investigation of lung development in physiologic and pathologic conditions. METHODS: Lungs were harvested from mouse embryos at E12.5 and cultured in three different settings, i.e., whole lung culture, mesenchyme-free epithelium culture, and organoid culture. For the whole lung culture, extracted lungs were embedded in Matrigel and incubated on permeable filters. Separately, distal epithelial tips were isolated by firstly removing mesothelial and mesenchymal cells, and then severing the tips from the airway tubes. These were then cultured either in branch-promoting or self-renewing conditions. RESULTS: Cultured whole lungs underwent branching morphogenesis similarly to native lungs. Real-time qPCR analysis demonstrated expression of key genes essential for lung bud formation. The culture condition for epithelial tips was optimized by testing different concentrations of FGF10 and CHIR99021 and evaluating branching formation. The epithelial rudiments in self-renewing conditions formed spherical 3D structures with homogeneous Sox9 expression. CONCLUSION: We report efficient protocols for ex vivo culture systems of pseudoglandular stage mouse embryonic lungs. These models can be applied to human samples and could be useful to paediatric surgeons to investigate normal lung development, understand the pathogenesis of congenital lung diseases, and explore novel therapeutic strategies.

An In Vitro Whole-Organ Liver Engineering for Testing of Genetic Therapies.

Explosion of gene therapy approaches for treating rare monogenic and common liver disorders created an urgent need for disease models able to replicate human liver cellular environment. Available models lack 3D liver structure or are unable to survive in long-term culture. We aimed to generate and test a 3D culture system that allows long-term maintenance of human liver cell characteristics. The in vitro whole-organ "Bioreactor grown Artificial Liver Model" (BALM) employs a custom-designed bioreactor for long-term 3D culture of human induced pluripotent stem cells-derived hepatocyte-like cells (hiHEPs) in a mouse decellularized liver scaffold. Adeno-associated viral (AAV) and lentiviral (LV) vectors were introduced by intravascular injection. Substantial AAV and LV transgene expression in the BALM-grown hiHEPs was detected. Measurement of secreted proteins in the media allowed non-invasive monitoring of the system. We demonstrated that humanized whole-organ BALM is a valuable tool to generate pre-clinical data for investigational medicinal products.

Successful Strategy for the Conservative Management of Acquired Tracheoesophageal Fistula Due to Lithium Button Battery Ingestion.

A 16-month-old boy was referred to our hospital for the management of suspected lithium button battery (LBB) ingestion. He had been previously well, but became febrile with a persistent cough resistant to oral antibiotics and dysphagia for 5 days. Radiography identified an LBB lodged in the upper esophagus. The LBB was retrieved under direct visualization with rigid laryngoscopy. He was sedated for 5 days and enteral feeding was commenced through a nasojejunal tube on the next day after procedure. On day 8 after retrieval, endoscopy and fluoroscopy identified a tracheoesophageal fistula (TEF), 6 mm in diameter. Conservative management was conducted with periodic follow-up endoscopies, which showed signs of healing in the esophagus. Following continuous antibiotics and proactive nutritional support, the TEF was found to have closed spontaneously by day 28 after the LBB removal. We present our experience of the successful nonsurgical management of acquired TEF secondary to LBB ingestion and aim to establish a protocol for managing it conservatively by reviewing the relevant literature.

Atypical rectoscrotal and rectoperineal fistula in male anorectal malformations: a case series of non-detaching strategies for preventing urethral injury.

Anorectal malformations (ARM) represent a broad spectrum of patients with different level of the rectum and type of a fistula. Standardized approaches are usually successful, but patients occasionally present with an unusual course of fistula which requires a modified surgical strategy. We present here three male ARM patients with an atypical fistula which did not have connection with the urinary tract, but ran near the fistula. Case 1 has a low-type ARM with a rectoscrotal fistula running deep and partly involved in the corpus spongiosum. Anorectoplasty was performed through an anterior sagittal incision and the anterior wall of the fistula was laid open leaving the posterior wall undetached. Case 2 was diagnosed with an intermediate-type ARM with a long rectoscrotal fistula running near and parallel the urethra. Posterior sagittal anorectoplasty (PSARP) was performed leaving the fistula untouched. Case 3 presented with an intermediate-type ARM with a rectoperineal fistula adherent to the urethra. The patient was treated by PSARP leaving the fistula and part of the muscle coat of the rectum in situ. All the cases were smoothly discharged and no urological complication nor problem associated with the residual fistula was observed at the latest follow-up (17 months-2 years). Preoperative distal colostography with the aid of diverting colostomy was importantly useful for deciding surgical procedure.

Long-term feeding issue and its impact on the daily life of congenital diaphragmatic hernia survivors: results of the first patient-led survey.

BACKGROUND: CDH UK is a registered charity governed by a volunteer committee and providing informal support to patients, families and healthcare workers affected directly or indirectly with congenital diaphragmatic hernia (CDH) internationally. This is the first patient-led survey undertaken by CDH UK aiming for highlighting the feeding problems and their impact on the daily life of CDH survivors. METHODS: Answers from CDH survivors were collected through an online questionnaire (SurveyMonkey®) undertaken by CDH UK. The questionnaire contained questions about their feeding problems and support they were receiving for it. MAIN RESULTS: Overall, 151 patients answered some parts of the survey and 102 patients completed the questionnaire. Overall, 116 (76.8%) responders reported suffering from any type of feeding issue. Gastric acid reflux (GER) and growth retardation were the commonest symptoms experienced by 97 (91.5%) and 72 (62.2%) responders, respectively. Only 18 (17.0%) responders have received any written information on feeding or details of patient/parent support. Eighty (75.5%) responders are satisfied with the level of support they are receiving, but 78 (76.4%) answered that the whole experience associated with the disease has been very or extremely stressful. CONCLUSIONS: CDH survivors frequently have various issues with feeding, which may not be adequately supported or discussed clinically. It is desirable to assist the patients to reliable resources of long-term support, including multidisciplinary team (MDT) approach.

Indications for Nonoperative Management of Uncomplicated Appendicitis in Children: A Prospective Analysis at a Single Institution.

Aim: To assess nonoperative management (NOM) of uncomplicated appendicitis (UC-appy) in children to determine factors influencing prognosis and review the literature. Materials and Methods: All UC-appy cases presenting younger than 16 years between 2015 and 2018 who had NOM (one dose of intravenous analgesia and intravenous piperacillin/tazobactam 112.5 mg/kg 8 hourly) and were followed up for at least 3 months were reviewed prospectively (n = 146). Perceived pain and fever were assessed 12 hourly, biochemistry daily. If predetermined cutoff results were not achieved at each assessment, NOM was abandoned and urgent laparoscopic appendectomy (ULA) performed. Results: NOM succeeded in 48.6% (S-NOM; n = 71) and failed in 51.4% (F-NOM; n = 75). Mean age at presentation (10.7 ± 2.5 versus 8.6 ± 3.7 years old; P < .0001) and duration of preadmission fever (1.0 ± 0.9 versus 2.1 ± 1.2 days; P < .0001) were the only significantly different criteria between S-NOM and F-NOM. Optimal cutoff values using receiver operating characteristic curve analysis were 7.0 years old (32% sensitivity and 93% specificity) and 1.0 day (95% sensitivity and 25% specificity), respectively. NOM was abandoned for persistent pain, prolonged fever, or raised white blood count at 12 hours in 20/75 (26.7%), 24 hours in 31/75 (41.3%), 36 hours in 14/75 (18.7%), and 48-72 hours in 10/75 (13.3%). At ULA, perforation was identified in 14/75 (18.7%). Complications arising within 3 months of ULA were residual abscess (n = 7/75; 9.3%) and transient ileus (n = 1/75; 1.3%). Conclusion: It would appear that surgery may be more appropriate for children with UC-appy when they are younger and febrile before admission for longer.

The learning curve of laparoscopic percutaneous extraperitoneal closure (LPEC) for inguinal hernia: protocoled training in a single center for six pediatric surgical trainees.

BACKGROUND: Laparoscopic 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. METHODS: This 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. RESULTS: During 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. CONCLUSIONS: Although 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.