Minimally invasive surgical approach in children treated for oesophageal atresia is associated with attention problems at school age: a prospective cohort study.

The long-term neurodevelopment of children born with oesophageal atresia (OA) is unclear. Therefore, we assessed the neurocognitive domains and their predictors. Patients born with OA between February 2006 and December 2014, who were routinely seen at eight years as part of a structured prospective longitudinal follow-up program, were included. Main outcome measures were need for school support, performance in various neurocognitive domains and potential predictors of neurocognitive problems. We analysed data of 65 children with a mean (SD) age of 8.1 (0.2) years, of whom 89% with OA type C. Thirty-five (54%) surgical corrections were minimally invasive; the median (interquartile range) duration of exposure to anaesthetics in the first 24 months was 398 (296 - 710) minutes. Forty-four (68%) attended regular education without extra support and intelligence was within normal range (99-108). More than 50% had z-scores ≤ -2 on one or more neurocognitive domains, of which attention was the most frequently affected domain. The speed on the sustained attention task was significantly below normal (z-score -1.48 (2.12), p < .001), as was fluctuation of sustained attention (z-score -3.19 (3.80), p < .001). The minimally invasive approach and a lower socio-economic status (both p = 0.006) proved significant predictors for sustained attention problems in multivariable analyses.  Conclusion: Children who undergo minimally invasive surgery for OA correction are at risk for sustained attention problems at school age. Future studies unravelling the effects of perioperative events on neurodevelopment should lead to optimal surgical, anaesthesiological, and intensive care management in the neonatal period. What is Known: • School-aged children born with oesophageal atresia have normal intelligence but problems with sustained attention at eight years. What is New: • Oesophageal atresia patients, who undergo minimally invasive surgery or who have a background of lower socioeconomic status are at serious risk for sustained attention problems at school age. • Moreover, those who have been intubated for a longer period are at risk for stronger fluctuations in sustained attention.

Automated control for investigation of the insufflation-ventilation interaction in experimental laparoscopy.

In laparoscopic surgery the abdominal cavity is insufflated with pressurized carbon dioxide gas to create workspace. This pressure is exerted through the diaphragm onto the lungs, competing with ventilation and hampering it. In clinical practice the difficulty of optimizing this balance can lead to the application of harmfully high pressures. This study set out to create a research platform for the investigation of the complex interaction between insufflation and ventilation in an animal model. The research platform was constructed to incorporate insufflation, ventilation and relevant hemodynamic monitoring devices, controlling insufflation and ventilation from a central computer. The core of the applied methodology is the fixation of physiological parameters by applying closed-loop control of specific ventilation parameters. For accurate volumetric measurements the research platform can be used in a CT scanner. An algorithm was designed to keep blood carbon dioxide and oxygen values stable, minimizing the effect of fluctuations on vascular tone and hemodynamics. This design allowed stepwise adjustment of insufflation pressure to measure the effects on ventilation and circulation. A pilot experiment in a porcine model demonstrated adequate platform performance. The developed research platform and protocol automation have the potential to increase translatability and repeatability of animal experiments on the biomechanical interactions between insufflation and ventilation.

A novel method for monitoring abdominal compliance to optimize insufflation pressure during laparoscopy.

BACKGROUND: Abdominal compliance describes the ease of expansion of the abdominal cavity. Several studies highlighted the importance of monitoring abdominal compliance (Cab) during the creation of laparoscopic workspace to individualize the insufflation pressure. The lack of validated clinical monitoring tools for abdominal compliance prevents accurate tailoring of insufflation pressure. Oscillometry, also known as the forced oscillation technique (FOT), is currently used to measure respiratory mechanics and has the potential to be adapted for monitoring abdominal compliance. This study aimed to define, develop and evaluate a novel approach which can monitor abdominal compliance during laparoscopy using endoscopic oscillometry. MATERIALS AND METHODS: Endoscopic oscillometry was evaluated in a porcine model for laparoscopy. A custom-built insufflator was developed for applying an oscillatory pressure signal superimposed onto a mean intra-abdominal pressure. This insufflator was used to measure the abdominal compliance at insufflation pressures ranging from 5 to 20 hPa (3.75 to 15 mmHg). The measurements were compared to the static abdominal compliance, which was measured simultaneously with computed tomography imaging. RESULTS: Endoscopic oscillometry recordings and CT images were obtained in 10 subjects, resulting in 76 measurement pairs for analysis. The measured dynamic Cab ranged between 0.0216 and 0.261 L/hPa while the static Cab based on the CT imaging ranged between 0.0318 and 0.364 L/hPa. The correlation showed a polynomial relation and the adjusted R-squared was 97.1%. CONCLUSIONS: Endoscopic oscillometry can be used to monitor changes in abdominal compliance during laparoscopic surgery, which was demonstrated in this study with a comparison with CT imaging in a porcine laparoscopy model. Use of this technology to personalize the insufflation pressure could reduce the risk of applying excessive pressure and limit the drawbacks of insufflation.

Recommendations for endoscopic surveillance after esophageal atresia repair in adults.

BACKGROUND: Endoscopic surveillance of adults with esophageal atresia is advocated, but the optimal surveillance strategy remains uncertain. This study aimed to provide recommendations on appropriate starting age and intervals of endoscopic surveillance in adults with esophageal atresia. METHODS: Participants underwent standardized upper endoscopies with biopsies. Surveillance intervals of 3-5 years were applied, depending on age and histopathological results. Patient's age and time to development of (pre)malignant lesions were calculated. RESULTS: A total of 271 patients with esophageal atresia (55% male; median age at baseline endoscopy 26.7 (range 15.6-68.5) years; colon interposition n = 17) were included. Barrett's esophagus was found in 19 (7%) patients (median age 32.3 (17.8-56.0) years at diagnosis). Youngest patient with a clinically relevant Barrett's esophagus was 20.9 years. Follow-up endoscopies were performed in 108 patients (40%; median follow-up time 4.6 years). During surveillance, four patients developed Barrett's esophagus but no dysplasia or cancer was found. One 45-year-old woman with a colon interposition developed an adenoma with high-grade dysplasia which was radically removed. Two new cases of esophageal carcinoma were diagnosed in patients (55 and 66 years old) who were not under surveillance. One of them had been curatively treated for esophageal carcinoma 13 years ago. CONCLUSIONS: This study shows that endoscopic screening of patients with esophageal atresia, including those with a colon interposition, can be started at 20 years of age. Up to the age of 40 years a surveillance interval of 10 years appeared to be safe. Endoscopic surveillance may also be warranted for patients after curative esophageal cancer treatment.

Surgical management of Encapsulating Peritoneal Sclerosis (EPS) in children: international case series and literature review.

BACKGROUND: Encapsulating Peritoneal Sclerosis (EPS) is a rare phenomenon in paediatric patients with kidney failure treated with peritoneal dialysis (PD). This study highlights clinical challenges in the management of EPS, with particular emphasis on peri-operative considerations and surgical technique. METHODS: Retrospective analysis of all paediatric patients with EPS treated at the Manchester Centre for Transplantation. RESULTS: Four patients were included with a median duration of 78 months on PD. All patients had recurrent peritonitis (> 3 episodes), and all had symptoms within three months of a change of dialysis modality from PD to haemodialysis or transplant. In Manchester, care was delivered by a multi-disciplinary team, including surgeons delivering the adult EPS surgical service with a particular focus on nutritional optimisation, sepsis control, and wound management. The surgery involved laparotomy, lavage, and enterolysis of the small bowel + / - stoma formation, depending on intra-abdominal contamination. Two patients had a formal stoma, which were reversed at three and six months, respectively. Two patients underwent primary closure of the abdomen, whereas two patients had re-look procedures at 48 h with secondary closure. One patient had a post-operative wound infection, which was managed medically. One patient's stoma became detached, leading to an intra-abdominal collection requiring re-laparotomy. The median length of stay was 25 days, and patients were discharged once enteral feeding was established. All patients remained free of recurrence with normal gut function and currently two out of four have functioning transplants. CONCLUSIONS: This series demonstrates 100% survival and parenteral feed independence following EPS surgery. Post-operative morbidity was common; however, with individualised experience-based decision-making and relevant additional interventions, patients made full recoveries. Health and development post-surgery continued, allowing the potential for transplantation. A higher resolution version of the Graphical abstract is available as Supplementary information.

Primary repair of esophageal atresia is followed by multiple diagnostic and surgical procedures.

BACKGROUND: Children born with esophageal atresia (EA) face comorbidities and complications often requiring surgery and anesthesia. We aimed to assess all procedures performed under general anesthesia during their first 12 years of life. METHODS: We performed a retrospective cohort study about subsequent surgeries and procedures requiring general anesthesia in children born with type C EA between January 2007 and December 2017, with follow-up to March 2019. RESULTS: Of 102 eligible patients, 63 were diagnosed with comorbidities, of whom 18 had VACTERL association. Follow-up time for all patients varied between 14 months and 12 years (median 7 years). The patients underwent total 637 procedures, median 4 [IQR2-7] per patient. In the first year of life, 464 procedures were performed, in the second year 69 and in the third year 29. Thirteen patients underwent no other procedures than primary EA repair. In 57 patients, 228 dilatations were performed. Other frequently performed procedures were esophagoscopy (n=52), urologic procedures (n=44) and abdominal procedures (n=33). CONCLUSIONS: Patients with EA frequently require multiple anesthetics for a variety of procedures related to the EA, complications and comorbidities. This study can help care providers when counselling parents of a patient with an EA by giving them more insight into possible procedures they can be confronted with during childhood.

Interventions with Music in PECTus excavatum treatment (IMPECT trial): a study protocol for a randomised controlled trial investigating the clinical effects of perioperative music interventions.

INTRODUCTION: Pectus excavatum repair is associated with substantial postoperative pain, despite the use of epidural analgesia and other analgesic regimens. Perioperative recorded music interventions have been shown to alleviate pain and anxiety in adults, but evidence for children and adolescents is still lacking. This study protocol describes a randomised controlled trial that evaluates the effects of recorded music interventions on postoperative pain relief in children and adolescents after pectus excavatum repair. METHODS: A multicentre randomised controlled trial was set up comparing the effects of perioperative recorded music interventions in addition to standard care with those of standard care only in patients undergoing a Nuss procedure for pectus excavatum repair. One hundred and seventy subjects (12-18 years of age) will be included in three centres in the Netherlands. Patient inclusion has started in November 2018, and is ongoing. The primary outcome is self-reported perceived pain measured on the visual analogue scale. Secondary outcomes are anxiety level, analgesics consumption, vital parameters such as heart rate, blood pressure and respiratory rate, length of hospital stay, postoperative complications, quality of life and cost-effectiveness. ETHICS AND DISSEMINATION: This study is being conducted in accordance with the Declaration of Helsinki. The Medical Ethics Review Board of Erasmus University Medical Centre Rotterdam, The Netherlands, has approved this protocol. Results will be disseminated via peer-reviewed scientific journals and conference presentations. TRIAL REGISTRATION NUMBER: NL6863.

Towards integrative neuromonitoring of the surgical newborn: A systematic review.

BACKGROUND: The altered neurodevelopment of children operated on during the neonatal period might be due to peri-operative changes in the homeostasis of brain perfusion. Monitoring of vital signs is a standard of care, but it does not usually include monitoring of the brain. OBJECTIVES: To evaluate methods of monitoring the brain that might be of value. We also wanted to clarify if there are specific risk factors that result in peri-operative changes and how this might be evaluated. DESIGN: Systematic review. DATA SOURCES: A structured literature search was performed in MEDLINE in Ovid, Embase, Cochrane CENTRAL, Web of Science and Google Scholar. ELIGIBILITY CRITERIA: Studies in neonates who received peri-operative neuromonitoring were eligible for inclusion; studies on neurosurgical procedures or cardiac surgery with cardiopulmonary bypass and/or deep hypothermia cardiac arrest were excluded. RESULTS: Nineteen of the 24 included studies, totalling 374 infants, reported the use of near-infrared spectroscopy. Baseline values of cerebral oxygenation greatly varied (mean 53 to 91%) and consequently, no coherent results were found. Two studies found a correlation between cerebral oxygenation and mean arterial blood pressure. Five studies, with in total 388 infants, used (amplitude-integrated) electro-encephalography to study peri-operative brain activity. Overall, the brain activity decreased during anaesthesia and epileptic activity was more frequent in the peri-operative phase. The association between intra-operative cerebral saturation or activity and neuro-imaging abnormalities and/or neurodevelopmental outcome was investigated in six studies, but no association was found. CONCLUSION: Neuromonitoring with the techniques currently used will neither help our understanding of the altered neonatal pathophysiology, nor enable early detection of deviation from the norm. The modalities lack specificity and are not related to clinical (long-term) outcome or prognosis. Accordingly, we were unable to draw up a monitoring guideline.

The effect of intralesional steroid injections on esophageal strictures and the child as whole: A case series.

BACKGROUND: The most frequent complication after esophageal atresia repair remains anastomotic stricture formation. The initial treatment is endoscopic dilatation. Intralesional steroid injection (ISI) might be an effective adjuvant treatment in case of recurrent strictures. In this series we present our initial experience with this intervention. METHODS: Data on primary surgery, stricture treatment, postoperative complications, outcome and growth were retrospectively collected from electronic patient records. Findings were analyzed by descriptive statistics and mixed model analysis. RESULTS: Between 2014 and 2017, ISI was performed for severe recurrent anastomotic strictures in six patients (median age at injection 12.4 (2.1-34.7) months) after a median of 6 (2-20) dilatations. In five patients ISI was successful and the stenosis was cleared. No postoperative complications were reported, especially none related to acute adrenal suppression. Comparing the year before with the year after ISI, a significant positive change for weight (r = 0.70, p = 0.003) was calculated versus a negative change for height (r = -0.87, p = 0.003). CONCLUSIONS: We found ISI to be an effective adjuvant treatment to recurrent anastomotic stricture dilatation after esophageal atresia repair, without postoperative complications or symptoms of adrenal suppression. It remains important, however, to monitor growth effects. Further evaluation is required in a large prospective study. TYPE OF STUDY: Treatment study, Level IV (case series).

Perioperative management of esophageal atresia/tracheo-esophageal fistula: An analysis of data of 101 consecutive patients.

BACKGROUND: The perioperative management of esophageal atresia/tracheo-esophageal fistula by open or thoracoscopic approach can be complicated by metabolic derangements. Little is known, however, about the severity of derangements of vital and metabolic parameters in the perioperative period. AIM: The aim of this study is to describe the perioperative courses of vital and metabolic parameters in 101 consecutive neonates undergoing surgical repair of esophageal atresia type C. METHOD: In a retrospective cohort study, we extracted all data from the electronic anesthetic and medical charts of patients who underwent esophageal atresia type C repair within 30 days of life (2007-2017). We distinguished three types of surgery: primary open, primary thoracoscopic, and primary thoracoscopic surgery converted to open surgery. Descriptive analysis was applied. RESULTS: The charts of 117 patients were reviewed: data of 101 were included. The perioperative anesthetic management was not standardized; various methods and medications were used for anesthesia induction and maintenance. Intraoperative blood gas analysis data of 72 patients were available and showed derangements regardless of type of surgery. The median pH-value decreased to 7.21 [IQR 7.14-7.30] and a pH-value below 7.20 was found in 29 patients; in four cases below 7.0, with the lowest value 6.83. The median PaCO2 reached an upper level of 7.5kPa [IQR 5.8-9.2]; in 13 cases above 10.0kPa, with a peak value of 25.8kPa. These high PaCO2 levels fluctuated with lowest measured PaCO2 of median 5.6 [IQR 4.5-6.6], with the lowest value 2.8kPa. The median PaO2 level reached an upper level of 16.9kPa [IQR 11.8-25.7], in 22 cases above 20.0kPa, with a peak value of 50.0kPa. These high levels fluctuated with lowest measured PaO2 levels of median 8.3kPa [IQR 6.73-10.5]; the lowest PaO2 value was 4.7 kPa. CONCLUSION: Open and thoracoscopic correction of esophageal atresia were associated with periods of severe metabolic derangements. These events need to be taken into account for the evaluation of esophageal atresia (surgical) care and in evaluations of short- and long-term outcomes.

Effects of Neonatal Thoracoscopic Surgery on Tissue Oxygenation: A Pilot Study on (Neuro-) Monitoring and Outcomes.

INTRODUCTION: Multiple reports have questioned the feasibility of neonatal thoracoscopic repair of congenital diaphragmatic hernia (CDH) and esophageal atresia (EA). The aim of this study is to examine the effects of CO2 pneumothorax on cerebral and renal rSO2 and to assess the potential predictive value of these data on neurodevelopmental outcome after neonatal thoracoscopic surgery for CDH or EA. MATERIALS AND METHODS: A prospective observational pilot study. Cerebral and renal regional tissue oxyhemoglobine saturation (rSO2) rSO2 were assessed using near-infrared spectroscopy (NIRS) during thoracoscopic surgery in neonates with CDH and with EA, in addition to routine anesthesia monitoring. Cerebral and renal rSO2, linked to repeated arterial blood gas analyses, heart rate, blood pressure, and to structured longitudinal neurodevelopmental follow-up. RESULTS: Baseline estimated marginal means of cerebral rSO2 values (CDH: 82%, EA: 91%) did not change significantly during pneumothorax (CDH: 81%, EA 79% [n.s. versus baseline]) despite severe acidosis (lowest pH, CDH: 6.99, EA: 7.1). Neurodevelopmental outcomes at 24 months were normal in all 7 patients who were available for evaluation. CONCLUSION: Neonatal thoracoscopic repair of CDH and EA using CO2-pneumothorax leads to severe acidosis. Cerebral rSO2 remained within clinical acceptable limits during intraoperative periods of acidosis. Neurodevelopmental outcome was favorable within the first 24 months. The potential of NIRS to further improve perioperative care and long-term outcome in this specific patient group deserves further investigation.

Implementation of a Quality Control System for Laparoscopic Pyloromyotomy in Hypertrophic Pyloric Stenosis: Hurdles and Pitfalls.

BACKGROUND: In 2011, we implemented a new video-based system for quality control of laparoscopic pyloromyotomy. More than 3 years later, we evaluated how the implementation had gone and assessed its usability in predicting postoperative outcomes. MATERIALS AND METHODS: Four key point images or short video-segments were to be recorded perioperatively: prepyloromyotomy, parallel-mobility testing, perforation testing, and postpyloromyotomy. Data of all 134 patients undergoing laparoscopic pyloromyotomy from September 2011 to December 2014 were analyzed retrospectively. Five pediatric surgeons independently assessed the anonymized operative images for predicting reoperation and time to full-enteral feeding. RESULTS: The percentage of operations during which images were recorded increased from 45% in 2012 to 75% in 2014. Over the study period, one or more images were recorded in 89 of the 134 (66%) patients. In only 17 of 89 patients (19%), all four images were documented. The key point images or videos were made for prepyloromyotomy in 49%, parallel-mobility testing in 85%, perforation testing in 42%, and postpyloromyotomy in 94% of 89 patients. Five patients (3.7%) were reoperated for incomplete pyloromyotomy (N = 4) or mucosal perforation (N = 1). Images were recorded during the first operation in four of the five reoperated patients. The need of reoperation was correctly predicted for two of the four patients. Full-enteral feeding within 24 hours was correctly predicted for 67% of the patients (range: 47-88%). CONCLUSION: The increase in recorded images over the years is promising. The implementation of the quality control system did not contribute to a significant decrease in the complication rate, which was already very low. Still, reoperation or a protracted postoperative course could only be predicted with moderate accuracy from the operative images, therefore, for now the use of perioperative images in a medicolegal setting should be advised against. Improved compliance with image recording and better instructions for evaluating the images might improve the usefulness of perioperative images in, e.g., telementoring, education, and medicolegal practice.

Safeguarding Infant Brains: A Multidisciplinary Challenge-Results of a Survey, Update on Current Scientific Evidence, and Recommendations on How to Deal with Possible Anesthetic Drug Neurotoxicity.

INTRODUCTION: Potential neurotoxicity of anesthetic drugs has been among the most intensively discussed issue in pediatric anesthesia for more than 10 years. It remains unclear how far this discussion has reached the European pediatric surgical community. Our aim was to investigate the thoughts of pediatric surgeons regarding this topic. In addition, we provide an update on the current scientific evidence regarding neurotoxicity together with recommendations for clinical practice. MATERIALS AND METHODS: A web-based survey to assess the thoughts of practicing European pediatric surgeons regarding neurotoxicity and how it may have influenced their daily practice of pediatric surgery was launched via the European Pediatric Surgeons' Association Web site. RESULTS: A total of 72 responses could be analyzed. A majority of the respondents were interested in the topic but felt a need to further explore it. Thirty-one respondents have changed their daily practice of pediatric surgery due to potential anesthetic drug toxicity. Eighteen respondents reported to be concerned about neurotoxicity, 29 held a neutral position, and 8 were not concerned. Twenty-seven respondents found it a shared responsibility of the surgeon and the anesthesiologist to deal with the neurotoxicity issue. The majority of respondents found a necessity for further research on anesthetic drug neurotoxicity, assigning the highest priority to prospective longitudinal human studies and the lowest to animal studies. CONCLUSION: The neurotoxicity question has reached the pediatric surgical community. Currently available scientific data do not support the theory of anesthetic drug-induced neurotoxicity in young children. Recent interdisciplinary clinical research focuses on neurodevelopmental outcome after surgery in neonates and infants. The European Safe Anesthesia For Every Tot initiative suggests focusing on proper conduct of anesthesia in children rather than on possible anesthetic drug neurotoxicity.

Thoracoscopic versus open repair of CDH in cardiovascular stable neonates.

BACKGROUND: Thoracoscopic surgery is an increasingly popular surgical technique to repair congenital diaphragmatic hernia (CDH). However, acidosis during surgery and the higher recurrence rate are considerable risk factors. The aim of this retrospective study is to compare the outcome of open versus thoracoscopic repair of the diaphragm in neonates with CDH with the same degree of cardiovascular and pulmonary illness who meet the criteria for thoracoscopic repair. METHODS: Retrospective analysis of all patients of two large national reference centers for CDH born in the years 2008 through 2012, and meeting the criteria for surgical repair on cardiopulmonary and physiological criteria according to the CDH EURO consortium consensus and meeting the criteria for thoracoscopic repair according to the review by Vijfhuize et al. The surgical technical aspects were comparable in both centers. RESULTS: 108 patients were included, of whom 75 underwent thoracoscopic repair and 34 underwent open repair. The gestational age and lung-to-head ratio were significantly lower and stay on the ICU significantly longer in the open-repair group. The operation time was longer (178 vs. 150 min, p = .012) and the recurrence rate higher (18.9 vs. 5.9 %, p = .036) in the thoracoscopic-repair group. The arterial pH, pO2, pCO2 and base excess before and after thoracoscopic repair were all significantly different. CONCLUSION: After critical selection for thoracoscopic repair of left-sided CDH based on the patient's preoperative condition, the outcomes of open repair were almost identical to those of thoracoscopic repair. A notable exception is the recurrence rate, which was significantly higher in the thoracoscopic-repair group. For the time being, thoracoscopic primary closure seems a safe and effective procedure, but efficacy of thoracoscopic patch repair has not been established.

Optimizing working space in laparoscopy: CT measurement of the influence of small body size in a porcine model.

INTRODUCTION: In our continuing research into the determinants of laparoscopic working space, the influence of small body size was investigated. METHODS: In eight 6-kg pigs, the effects of intraabdominal CO2 pneumoperitoneum pressure (IAP), prestretching of the abdominal wall, and neuromuscular blockade (NMB) on laparoscopic working space volume and distances were studied. Computed tomography was used to measure working space during two stepwise abdominal insufflation-runs up to an IAP of 15mm Hg. Results were compared with data from earlier experiments in 20-kg pigs. RESULTS: Cardiorespiratory parameters were stable up to an IAP of 8-10mm Hg. In 6-kg pigs working-space dimensions were five times smaller than in 20-kg pigs. Working-space volume, anteroposterior (AP) diameter and symphysis-diaphragm distance increased linearly up to an IAP of 8mm Hg. Above 8mm Hg, compliance decreased. Eighty percent of the total volume (618ml) and of AP diameter (3cm) at 15mm Hg had been achieved at an IAP of 10mm Hg. Prestretching by a first insufflation resulted in a statistically significant increase in working space volume and in AP diameter during the second insufflation. This effect was significantly larger than in 20-kg pigs. Neuromuscular blockade did not have a significant effect on working-space. CONCLUSIONS: Working space in growing individuals is very limited. Eighty percent of the working space created by an IAP of 15mm Hg was already achieved at 10mm Hg, while cardiorespiratory side effects at an IAP of 8-10mm Hg seem acceptable. Prestretching of the abdominal wall significantly increased working space, even more so than in 20-kg pigs. As in 20-kg pigs, NMB had no significant effect on laparoscopic working space. Prestretching of the abdominal wall is a promising cheap, safe and easy strategy to increase laparoscopic working space, lessening the need for prolonged high-pressure pneumoperitoneum.

Optimizing working space in laparoscopy: CT-measurement of the effect of neuromuscular blockade and its reversal in a porcine model.

OBJECTIVE: The objective of this paper was to determine the effect of neuromuscular blockade (NMB) on working space in a porcine laparoscopy model. BACKGROUND: Conflicting results on the effect of NMB on laparoscopic working space are found in literature. Almost all studies are limited by absence of objective assessment of working space or use surrogate outcomes. METHODS: In a standardized porcine laparoscopy model, laparoscopic working-space dimensions with and without NMB were investigated in 16 animals using computed tomography at intra-abdominal pressures of 0, 5, 10, and 15 mmHg during multiple runs of abdominal insufflation. RESULTS: No statistically significant effect of NMB on abdominal dimensions and laparoscopic working-space volume was found during CO2 pneumoperitoneum. In contrast, the effect of pre-stretching of the abdominal wall by a previous abdominal insufflation was found to be significant. CONCLUSIONS: This experimental study confirms the results from several clinical studies that NMB does not influence laparoscopic working space. Studies dealing with working space during laparoscopy should take note of pre-stretching bias.

Optimizing working space in laparoscopy: CT measurement of the effect of pre-stretching of the abdominal wall in a porcine model.

BACKGROUND: Determinants of working space in minimal access surgery have not been well studied. Using computed tomography (CT) to measure volumes and linear dimensions, we are studying the effect of a number of determinants of CO2 working space in a porcine laparoscopy model. Here we report the effects of pre-stretching of the abdominal wall. METHODS: Earlier we had noted an increase in CO2 pneumoperitoneum volume at repeat insufflation with an intra-abdominal pressure (IAP) of 5 mmHg after previous stepwise insufflation up to an IAP of 15 mmHg. We reviewed the data of this serendipity group; data of 16 pigs were available. In a new group of eight pigs, we also explored this effect at repeat IAPs of 10 and 15 mmHg. Volumes and linear dimensions of the CO2 pneumoperitoneum were measured on reconstructed CT images and compared between the initial and repeat insufflation runs. RESULTS: Previous stepwise insufflation of the abdomen with CO2 up to 15 mmHg significantly (p < 0.01) increased subsequent working-space volume at a repeat IAP of 5 mmHg by 21 %, 7 % at a repeat IAP of 10 mmHg and 3 % at a repeat IAP of 15 mmHg. The external anteroposterior diameter significantly (p < 0.01) increased by 0.5 cm (14 %) at repeat 5 mmHg. Other linear dimensions showed a much smaller change. There was no statistically significant correlation between the duration of the insufflation run and the volume increase after pre-stretching at all IAP levels. CONCLUSIONS: Pre-stretching of the abdominal wall allows for the same surgical-field exposure at lower IAPs, reducing the negative effects of prolonged high-pressure CO2 pneumoperitoneum on the cardiorespiratory system and microcirculation. Pre-stretching has important scientific consequences in studies addressing ways of increasing working space in that its effect may confound the possible effects of other interventions aimed at increasing working space.

Increased incidence of hypertrophic pyloric stenosis in esophageal atresia patients.

INTRODUCTION: Around half of patients with esophageal atresia (EA) have additional congenital anomalies. Hypertrophic pyloric stenosis (HPS) in these patients is less known, with only 36 cases reported in the past literature. This retrospective study aimed to establish the incidence and clinical presentation of EA patients in combination with HPS in our hospital. MATERIALS AND METHODS: A retrospective study was based on the medical histories from all patients with EA who underwent surgical repair in our hospital from 1988 through 2012. RESULTS: Of 267 patients with EA, 20 also developed HPS (7.5%). The latter group showed male predominance, 90 versus 60% in the EA without HPS group. The first symptoms of HPS were mostly vomiting and/or feeding intolerance (n = 19). The diagnosis was mostly delayed, with a median of 6 days (range, 1-21 days). CONCLUSIONS: This is the first report on the high incidence of HPS in a large series of EA patients. The incidence found is 30 times higher than that in the normal population. HPS should be considered when patients show recurrent or persisting vomiting and feeding intolerance after surgery. The reason for the higher incidence should be further investigated.