Surgical Treatment of Short Bowel Syndrome-The Past, the Present and the Future, a Descriptive Review of the Literature.

Short bowel syndrome (SBS) is a devastating disorder with both short- and long-term implications for patients. Unfortunately, the prevalence of SBS has doubled over the past 40 years. Broadly speaking, the etiology of SBS can be categorized as congenital or secondary, the latter typically due to extensive small bowel resection following diseases of the small intestine, e.g., necrotizing enterocolitis, Hirschsprung's disease or intestinal atresia. As of yet, no cure exists, thus, conservative treatment, primarily parenteral nutrition (PN), is the first-line therapy. In some cases, weaning from PN is not possible and operative therapy is required. The invention of the longitudinal intestinal lengthening and tailoring (LILT or Bianchi) procedure in 1980 was a major step forward in patient care and spawned further techniques that continue to improve lives for patients with severe SBS (e.g., double barrel enteroplasty, serial transverse enteroplasty, etc.). With this review, we aim to provide an overview of the clinical implications of SBS, common conservative therapies and the development of operative techniques over the past six decades. We also provide a short outlook on the future of operative techniques, specifically with respect to regenerative medicine.

Anatomy of the neural fibers at the superior mesenteric artery-a cadaver study.

PURPOSE: Most surgeons perform right-sided semicircular clearance of the superior mesenteric artery (SMA) nerve plexus for pancreatic head carcinoma, presuming a linear course of the SMA nerve fibers. The hypothesis was that the SMA nerve plexus fibers follow a non-linear course, and the goal of the present study was to assess the neural fibers distribution along the SMA. METHODS: The course of neural fibers along the retropancreatic and suprapancreatic SMA was assessed in 7 cadavers. RESULTS: In the retropancreatic course of the vessel, the main nerve cords branch and form a large number of finer nerve branches performing an anti-clockwise rotation of slightly less than 90° around the SMA. Finer nerve branches are located rather close to the vessel, while the main nerve cords are localized in the loose connective tissue of the peripheral parts of the vascular sheath. Nerve fibers around the suprapancreatic SMA run as two main nerve cords framing the artery on the right lateral-ventral and the left lateral to lateral-dorsal side. CONCLUSION: The rotation of the nerve fiber around the SMA indicates that a more radical resection of at least 180° of neural tissue around the SMA might be required to achieve tumor clearance in pancreatic cancer with perineural invasion at the uncinate margin.

Open Versus Laparoscopic Pyloromyotomy for Pyloric Stenosis-A Systematic Review and Meta-Analysis.

INTRODUCTION: Infantile hypertrophic pyloric stenosis is treated by either open pyloromyotomy (OP) or laparoscopic pyloromyotomy (LP). The aim of this meta-analysis was to compare the open versus laparoscopic technique. METHODS: A literature search was conducted from 1990 to February 2021 using the electronic databases MEDLINE, Embase, and Cochrane Central Register of Controlled Trials. Primary outcomes were mucosal perforation and incomplete pyloromyotomy. Secondary outcomes consisted of length of hospital stay, time to full feeds, operating time, postoperative wound infection/abscess, incisional hernia, hematoma/seroma formation, and death. RESULTS: Seven randomized controlled trials including 720 patients (357 with OP and 363 with LP) were included. Mucosal perforation rate was not different between groups (relative risk [RR] LP versus OP 1.60 [0.49-5.26]). LP was associated with nonsignificant higher risk of incomplete pyloromyotomy (RR 7.37 [0.92-59.11]). There was no difference in neither postoperative wound infections after LP compared with OP (RR 0.59 [0.24-1.45]) nor in postoperative seroma/hematoma formation (RR 3.44 [0.39-30.43]) or occurrence of incisional hernias (RR 1.01 [0.11-9.53]). Length of hospital stay (-3.01 h for LP [-8.39 to 2.37 h]) and time to full feeds (-5.86 h for LP [-15.95 to 4.24 h]) were nonsignificantly shorter after LP. Operation time was almost identical between groups (+0.53 min for LP [-3.53 to 4.59 min]). CONCLUSIONS: On a meta-level, there is no precise effect estimate indicating that LP carries a higher risk for mucosal perforation or incomplete pyloromyotomies compared with the open equivalent. Because of very low certainty of evidence, we do not know about the effect of the laparoscopic approach on postoperative wound infections, postoperative hematoma or seroma formation, incisional hernia occurrence, length of postoperative stay, time to full feeds, or operating time.

CT-based patient-specific instrumentation for total knee arthroplasty in over 700 cases: single-use instruments are as accurate as standard instruments.

PURPOSE: Efforts in total knee arthroplasty are made to improve accuracy for a correct leg axis and reduce component malpositioning using patient-specific instruments. It was hypothesized that use of patient-specific instruments (vs. computer-navigated and conventional techniques) will reduce the number of outliers. Our second hypothesis was that single-use instrumentation will lead to the same accuracy compared to patient-specific instruments made of metal. METHODS: 708 primary total knee arthroplasties between 2014 and 2018 using computer tomography (CT)-based patient-specific cutting block technique and a preoperative planning protocol were retrospectively reviewed. Preoperative data [hip-knee-angle (HKA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), tibial slope, femoral component flexion] was compared to postoperative performed standard radiological follow-up X-rays. Differences of > 3° between measurements were defined as outliers. RESULTS: Overall 500 prostheses using standard instrumentation and 208 prostheses using single-use instruments were implanted. Preoperative HKA axes (- 1.2°; p < 0.001), femoral component flexion (Δ 0.8°, p < 0.001), LDFA (Δ - 1.5°, p < 0.001), MPTA (Δ - 0.5°, p < 0.001) and tibial posterior slopes (Δ 0.5°, p < 0.001), respectively, were different from postoperative axes. More outliers occurred using standard (vs. single-use) instruments (p < 0.001) regarding postoperative HKA (ranges of standard- vs. single-use: instruments: HKA 178.0°-180.5° vs. 178.0°-180.5°, femoral component flexion 0.0°-6.0° vs. 0.0°-4.5°, LDFA 90.0°-91.0° vs. 90.0°-90.0°, MPTA 90.0°-90.0° vs. 90.0°-90.0°, tibial posterior slope - 10° to 10° vs. - 1° to 10°). No differences were seen for other angles measured. Comparing both systems, total number of outliers was higher using standard (8%) vs. single-use instruments (4.3%). CONCLUSION: This study shows a high accuracy of CT-based patient-specific instrumentation concerning postoperative achieved knee angles and mechanical leg axes. Single-use instruments showed a similar accuracy. LEVEL OF EVIDENCE: III.

Effect of high altitude on human postprandial 13 C-octanoate metabolism, intermediary metabolites, gastrointestinal peptides, and visceral perception.

OBJECTIVE: At high altitude (HA), acute mountain sickness (AMS) is accompanied by neurologic and upper gastrointestinal symptoms (UGS). The primary aim of this study was to test the hypothesis that delayed gastric emptying (GE), assessed by 13 C-octanoate breath testing (OBT), causes UGS in AMS. The secondary aim was to assess post-gastric mechanisms of OBT, which could confound results under these conditions, by determination of intermediary metabolites, gastrointestinal peptides, and basal metabolic rate. METHODS: A prospective trial was performed in 25 healthy participants (15 male) at 4559 m (HA) and at 490 m (Zurich). GE was assessed by OBT (428 kcal solid meal) and UGS by visual analogue scales (VAS). Blood sampling of metabolites (glucose, free fatty acids (FFA), triglycerides (TG), beta-hydroxyl butyrate (BHB), L-lactate) and gastrointestinal peptides (insulin, amylin, PYY, etc.) was performed as well as blood gas analysis and spirometry. STATISTICAL ANALYSIS: variance analyses, bivariate correlation, and multilinear regression analysis. RESULTS: After 24 h under hypoxic conditions at HA, participants developed AMS (p < 0.001). 13 CO2 exhalation kinetics increased (p < 0.05) resulting in reduced estimates of gastric half-emptying times (p < 0.01). However, median resting respiratory quotients and plasma profiles of TG indicated that augmented beta-oxidation was the main predictor of accelerated 13 CO2 -generation under these conditions. CONCLUSION: Quantification of 13 C-octanoate oxidation by a breath test is sensitive to variation in metabolic (liver) function under hypoxic conditions. 13 C-breath testing using short-chain fatty acids is not reliable for measurement of gastric function at HA and should be considered critically in other severe hypoxic conditions, like sepsis or chronic lung disease.

Statistics decrypted-a comprehensive review and smartphone-assisted five-step approach for good statistical practice.

BACKGROUND: Statistic scripts are often made by mathematicians and cryptic for clinicians or non-mathematician scientists. Nevertheless, almost all research projects necessitate the application of some statistical tests or at least an understanding thereof. The present review aims on giving an overview of the most common statistical terms and concepts. It further ensures good statistical practice by providing a five-step approach guiding the reader to the correct statistical test. METHODS AND RESULTS: First, different types of variables and measurements to describe a data set with means of descriptive statistics are introduced. The basic thoughts and tools of interferential statistics are presented, and different types of bias are discussed. Then in the final paragraph, the most commonly used statistical tests are described. A smartphone app accessible via QR code finally guides the reader in five steps to the correct statistical test, depending on the data used in order to avoid commonly performed mistakes. CONCLUSIONS: The five-step approach sets a new minimal standard for good statistical practice.

Minimally Invasive Total Extraperitoneal Varicocele Repair: First Description in Children.

Introduction: The aim of this study was to report the first pediatric case series treated with minimally invasive total extraperitoneal varicocele (MITEV) repair using the total extraperitoneal (TEP) approach. Materials and Methods: Five male adolescents (12-17 years) were included in this study, all with left-sided Grade III varicoceles. A 5 mm camera port was inserted just below the umbilicus and two 5 mm working ports were used, one above the symphysis in the midline and the other in the left lateral hemiabdomen just below the arcuate line. Results: Operation time ranged from 47 to 61 minutes (mean: 53 minutes). There were no intra- or postoperative complications. The peritoneum was not perforated, and the abdominal cavity was not entered. Two patients had resolution from varicoceles on follow-up clinical examination and ultrasonography was performed 6 months after surgery. In 3 patients, long-term follow-up was pending. Conclusion: MITEV repair reflects a new minimally invasive access to the retroperitoneum in children with varicocele.

Corrigendum: Microbial Colonization From the Fetus to Early Childhood-A Comprehensive Review.

[This corrects the article DOI: 10.3389/fcimb.2020.573735.].

Failed preoperative vacuum bell therapy does not affect outcomes following minimally invasive repair of pectus excavatum.

PURPOSE: It is unknown if failed preoperative vacuum bell (VB) treatment in patients undergoing minimally invasive repair of pectus excavatum (MIRPE), delays repair and/or affects postoperative outcomes. METHODS: A retrospective data analysis including all consecutive patients treated at one single institution undergoing MIRPE was performed between 2000 and 2016. Patients were stratified into preoperative VB therapy versus no previous VB therapy. RESULTS: In total, 127 patients were included. Twenty-seven (21.3%) patients had preoperative VB treatment for 17 months (median, IQR 8-34). All 27 patients stopped VB treatment due to the lack of treatment effect. Eight (47.1%) of 17 assessed VB patients showed signs of skin irritation or hematoma. VB treatment had no effect on length of hospital stay (p = 0.385), postoperative complications (p = 1.0), bar dislocations (p = 1.0), and duration of bar treatment (p = 0.174). Time spent in intensive care unit was shorter in patients with VB therapy (p = 0.007). Long-term perception of treatment including rating of primary operation (p = 0.113), pain during primary operation (p = 0.838), own perspective of look of chest (p = 0.545), satisfaction with the procedure (p = 0.409), and intention of doing surgery again (p = 1.0) were not different between groups. CONCLUSIONS: Failed preoperative VB therapy had no or minimal effect on short-term outcomes and long-term perceptions following MIRPE.

Abdominal Wall Defects-Current Treatments.

Gastroschisis and omphalocele reflect the two most common abdominal wall defects in newborns. First postnatal care consists of defect coverage, avoidance of fluid and heat loss, fluid administration and gastric decompression. Definitive treatment is achieved by defect reduction and abdominal wall closure. Different techniques and timings are used depending on type and size of defect, the abdominal domain and comorbidities of the child. The present review aims to provide an overview of current treatments.

Establishment of Single-Port, Laparoscopic, Pediatric Hernia Repair in a Developing Country.

Background: Single-port, laparoscopic, needle-assisted, inguinal hernia repair (LNAR) in children intends to reduce surgical trauma and enables contralateral assessment and closure of contralateral patent processus vaginalis if necessary. The aim of the present study was to demonstrate that laparoscopic inguinal repair can be performed safely and cost-effectively in a developing country where laparoscopy is not yet commonly used. Methods: In this single-center study, we included all children undergoing LNAR between January 2017 and December 2018. Intraoperative and postoperative complications and hospital costs were assessed. Results: We performed 148 hernia repair operations in 117 children (age range 1 month to 15 years). Mean operative time was 20.8 ± 9.4 minutes. Mean length of hospital stay amounted to 10 ± 7.6 hours, with 77.7% of patients discharged within 6 hours. No intraoperative complications occurred in any patient. Complications occurred in six (5.1%) patients. Three (2.5%) patients experienced residual hydrocele, two (1.4%) patients suffered wound site seroma, and one (0.67%) patient experienced recurrent inguinal hernia 6 months after the initial repair. All complications occurred during the first year of the study period. Likewise, operative time (P < .0001) as well as duration of hospital stay (P < .0001) was significantly shorter in the second year. Total costs for complete treatment were below USD 80 per patient, which is comparable with the costs associated with open herniotomy at the same institution. Conclusion: Single-port LNAR and hydrocele repair in children were established safely and cost-effectively in a developing country. Nevertheless, the procedure was associated with a steep learning curve.

Hirschsprung disease and anorectal malformations - An uncommon association.

BACKGROUND: The simultaneous occurrence of Hirschsprung disease (HD) and anorectal malformation (ARM) is extremely rare, with only a very limited amount of cases published in the literature. Constipation is a major problem in patients operated for ARM, and biopsies from the distal rectum in patients with ARM may not show ganglion cells owing to different reasons, leading to a false positive diagnosis of HD. A pull-through procedure for HD after previous anorectoplasty for ARM always leads to fecal incontinence. The aim of the present study was to assess the incidence of simultaneous diagnoses of ARM and HD in a single large cohort of ARM patients and to demonstrate that biopsies from the anal canal, which are negative for ganglion cells, may mislead to a diagnosis of HD. MATERIALS AND METHODS: A retrospective review of our database from 1980 to 2018 identified 164 patients with HD and 2397 patients with ARM. Four patients suffered from both HD and ARM. RESULTS: The incidence of HD in ARM patients was 4/2397 = 0.17%, and the incidence of ARM in HD patients was 4/164 = 2.4%. CONCLUSION: Our results strongly suggest that the association of ARM and HD is less common than previously reported. TYPE OF STUDY: Therapeutic LEVEL OF EVIDENCE: IV.

Bladder Duplication - A Case Series.

OBJECTIVE: To describe 5 cases with complete urinary bladder duplication, their associated conditions, and their respective treatment. Urinary bladder duplication is an extremely rare congenital anomaly of the urinary system. So far about 70 cases have been published in the English literature, most of them as case reports and a few case series. METHODS AND RESULTS: All consecutive patients with bladder duplication treated at our institution between 2000 and 2015 were included. Patient records were retrospectively analyzed, and 5 patients with urinary bladder duplication were identified (see Summary Figure). Two patients were male. All duplications were recognized by health care providers. In 1 case recognition was prenatal (MRI in utero at 22 weeks of gestation), the latest recognition was at 12 months of age. A voiding cystourethrography was performed in 4 patients to confirm the diagnosis. In 4 patients the bladder duplication could be classified according to Abrahamson with 3 complete reduplications and one complete sagittal septum. All patients suffered from associated congenital diseases, but only one patient had urinary tract infections. Surgical treatment was only performed in one patient. Median follow-up was 34 months. DISCUSSION: Urinary bladder duplications reflect extremely seldom disorders that are almost always associated with other congenital anomalies. Treatment depends on patients' symptoms and associated conditions and hence needs to be individualized to each patient.

Congenital diaphragmatic hernias: Severe defect grade predicts the need for fundoplication.

Over one-third of infants with congenital diaphragmatic hernia (CDH) eventually require a Nissen fundoplication (NF). We examined pre- and intraoperative predictors for need of a NF in children undergoing CDH repair to elucidate, which patients will need a later NF.A retrospective analysis of all consecutive patients undergoing CDH repair at our institution from 2008 to 2018 was performed. Patients who underwent a NF were compared to those who did not (noNissen). Logistic regression analysis was performed to find independent predictors for NF in patients undergoing CDH repair. Severe Defect Grade was defined as defect >50% of the hemidiaphragm and intrathoracic liver.One hundred twenty-six patients were included, 42 (33%) underwent NF at a median of 61 days after CDH repair. Intrathoracic liver was more frequent in the NF (71%) versus noNissen (45%) group (P = .008). Absence of >50% of the hemidiaphragm was more frequent in the NF group (76% vs 31%, P < .001). Severe Defect Grade emerged as independent predictor for NF (odds ratio 7, 95% confidence interval 3-16, P < .001).Severe Defect Grade emerged as independent predictor for NF after CDH repair.

ACE2 and gut amino acid transport.

ACE2 is a type I membrane protein with extracellular carboxypeptidase activity displaying a broad tissue distribution with highest expression levels at the brush border membrane (BBM) of small intestine enterocytes and a lower expression in stomach and colon. In small intestinal mucosa, ACE2 mRNA expression appears to increase with age and to display higher levels in patients taking ACE-inhibitors (ACE-I). There, ACE2 protein heterodimerizes with the neutral amino acid transporter Broad neutral Amino acid Transporter 1 (B0AT1) (SLC6A19) or the imino acid transporter Sodium-dependent Imino Transporter 1 (SIT1) (SLC6A20), associations that are required for the surface expression of these transport proteins. These heterodimers can form quaternary structures able to function as binding sites for SARS-CoV-2 spike glycoproteins. The heterodimerization of the carboxypeptidase ACE2 with B0AT1 is suggested to favor the direct supply of substrate amino acids to the transporter, but whether this association impacts the ability of ACE2 to mediate viral infection is not known. B0AT1 mutations cause Hartnup disorder, a condition characterized by neutral aminoaciduria and, in some cases, pellagra-like symptoms, such as photosensitive rash, diarrhea, and cerebellar ataxia. Correspondingly, the lack of ACE2 and the concurrent absence of B0AT1 expression in small intestine causes a decrease in l-tryptophan absorption, niacin deficiency, decreased intestinal antimicrobial peptide production, and increased susceptibility to inflammatory bowel disease (IBD) in mice. Thus, the abundant expression of ACE2 in small intestine and its association with amino acid transporters appears to play a crucial role for the digestion of peptides and the absorption of amino acids and, thereby, for the maintenance of structural and functional gut integrity.

Is it worth to explore the contralateral side in unilateral childhood inguinal hernia?: A PRISMA-compliant meta-analysis.

BACKGROUND: It is still not clear if the contralateral side should be explored in children with unilateral inguinal hernias. The primary aim of the present study was to assess the incidence of metachronous contralateral inguinal hernias (MCIHs) in the pediatric population. The second aim was to assess factors associated with increased risk of MCIH development. METHODS: Prospective studies including patients from 0-19 years undergoing unilateral inguinal hernia repair without surgical exploration of the contralateral side between 1947 and April 2020 with a minimal follow-up of one year were searched. Searches included EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Trials. RESULTS: Seven studies involving 1774 children (1452 boys (82%) and 322 girls (18%) were identified. Overall the incidence of MCIH was 6%. Incidence of MCIH development was significantly higher in children with initial left-sided (9%) versus right-sided (3%) hernia (OR 2.55 with 95% CI from 1.56 to 4.17; P = 0.0002), in female (8%) versus male (4%) children (OR 1.74 with 95% CI from 1.01 to 3.01; P = 0.0469) and in patients with open (14%) versus closed (3%) contralateral processus vaginalis (CPV) (OR 4.17 with 95% CI from 1.25 to 13.9; P = 0.0202). There was no significant difference in MCIH development depending on follow-up duration (follow-up of ≤2 years (i.e. 1-2 years): calculated MCIH incidence 5% (95% CI from 0.00 to 0.11%; 3 studies; 569 patients), follow-up of ≥3 years (i.e. 3-4 years): 6% (95% CI from 0.03 to 0.09; 3 studies, 983 patients)) or patients' age (MCIH incidence in children <1 year: 6.9%; older children: 4.5%; OR 1.87 with 95% CI from 0.97 to 3.62; P = 0.0618). CONCLUSIONS: Overall incidence of MCIH development is 6%. Initial left-sided hernia, female gender and open CPV are risk factors for MCIH development.

SARS-CoV-2 receptor ACE2 gene expression in small intestine correlates with age.

Gastrointestinal symptoms are common in COVID-19 patients, especially in younger patients. Our hypothesis was that intestinal SARS-CoV-2 receptor ACE2 expression depends on patients' age. We examined duodenal biopsies from 43 healthy human adults. ACE2 gene expression was directly correlated with age (Spearman's r = 0.317, p = 0.039). With each year, duodenal ACE2 expression increased by 0.083 RU. The higher intestinal ACE2 mRNA expression in older patients may impact on their susceptibility to develop intestinal symptoms.

Evidence according to Cochrane Systematic Reviews on Alterable Risk Factors for Anastomotic Leakage in Colorectal Surgery.

Anastomotic leakage reflects a major problem in visceral surgery, leading to increased morbidity, mortality, and costs. This review is aimed at evaluating and summarizing risk factors for colorectal anastomotic leakage. A generalized discussion first introduces risk factors beginning with nonalterable factors. Focus is then brought to alterable impact factors on colorectal anastomoses, utilizing Cochrane systematic reviews assessed via systemic literature search of the Cochrane Central Register of Controlled Trials and Medline until May 2019. Seventeen meta-anaylses covering 20 factors were identified. Thereof, 7 factors were preoperative, 10 intraoperative, and 3 postoperative. Three factors significantly reduced the incidence of anastomotic leaks: high (versus low) surgeon's operative volume (RR = 0.68), stapled (versus handsewn) ileocolic anastomosis (RR = 0.41), and a diverting ostomy in anterior resection for rectal carcinoma (RR = 0.32). Discussion of all alterable factors is made in the setting of the pre-, intra-, and postoperative influencers, with the only significant preoperative risk modifier being a high colorectal volume surgeon and the only significant intraoperative factors being utilizing staples in ileocolic anastomoses and a diverting ostomy in rectal anastomoses. There were no measured postoperative alterable factors affecting anastomotic integrity.