Dimensional compatibility of rigid ventilating bronchoscopes with pediatric airway anatomy using different recommendations for age-related sizing-A bench study.

BACKGROUND: Appropriate size selection of pediatric rigid bronchoscopes is fundamental to avoidance of airway trauma and to a high success rate with the first intubation attempt. The aim of the present study was to compare the outer diameters of pediatric rigid bronchoscopes with the anatomical data on the pediatric airway. METHODS: Outer diameters (OD) of pediatric rigid ventilating bronchoscopes as given by the manufacturer were compared with published computed tomography internal diameters (ID) of the cricoid outlet, the trachea as well as the left and right proximal mainstem bronchus, using six published recommendations for age-related size selection. The ratios between a specific OD and ID were calculated and given as percentage values (%) for lower and upper age ranges. RESULTS: Nominal sized 2.5, 3, 3.5, 3.7, 4, 4.5, 5, and 6 rigid bronchoscopes were included. In five recommendations, the rigid bronchoscopes' OD was larger than the internal cricoid diameter in the upper age range, whereas in one recommendation the ratio (OD rigid bronchoscope to ID of cricoid) ranged between 77% and 90% for the upper age and between 95% and 109% for the lower age range. In only one of the six recommendations was the rigid bronchoscope OD larger than the tracheal ID. Ratios for the left and right proximal mainstem bronchus ranged from 70% to 146% for the upper and from 78% to 156% for the lower age range, with the highest ratios for the left proximal mainstem bronchus. CONCLUSION: Based on this in vitro study, most of the recommendations analyzed result in a balanced fit of rigid bronchoscopes within the cricoid. Since the left mainstem bronchus is considerably smaller than the cricoid, any insertion on this level will require careful endoscopic guidance to avoid damage to the left mainstem bronchus.

Pediatric Airway Endoscopy: Recommendations of the Society for Pediatric Pneumology.

For many decades, pediatric bronchoscopy has been an integral part of the diagnosis and treatment of acute and chronic pulmonary diseases in children. Rapid technical advances have continuously influenced the performance of the procedure. Over the years, the application of pediatric bronchoscopy has considerably expanded to a broad range of indications. In this comprehensive and up-to-date guideline, the Special Interest Group of the Society for Pediatric Pneumology reviewed the most recent literature on pediatric bronchoscopy and reached a consensus on a safe technical performance of the procedure.

In-situ muconic acid extraction reveals sugar consumption bottleneck in a xylose-utilizing Saccharomyces cerevisiae strain.

BACKGROUND: The current shift from a fossil-resource based economy to a more sustainable, bio-based economy requires development of alternative production routes based on utilization of biomass for the many chemicals that are currently produced from petroleum. Muconic acid is an attractive platform chemical for the bio-based economy because it can be converted in chemicals with wide industrial applicability, such as adipic and terephthalic acid, and because its two double bonds offer great versatility for chemical modification. RESULTS: We have constructed a yeast cell factory converting glucose and xylose into muconic acid without formation of ethanol. We consecutively eliminated feedback inhibition in the shikimate pathway, inserted the heterologous pathway for muconic acid biosynthesis from 3-dehydroshikimate (DHS) by co-expression of DHS dehydratase from P. anserina, protocatechuic acid (PCA) decarboxylase (PCAD) from K. pneumoniae and oxygen-consuming catechol 1,2-dioxygenase (CDO) from C. albicans, eliminated ethanol production by deletion of the three PDC genes and minimized PCA production by enhancing PCAD overexpression and production of its co-factor. The yeast pitching rate was increased to lower high biomass formation caused by the compulsory aerobic conditions. Maximal titers of 4 g/L, 4.5 g/L and 3.8 g/L muconic acid were reached with glucose, xylose, and a mixture, respectively. The use of an elevated initial sugar level, resulting in muconic acid titers above 2.5 g/L, caused stuck fermentations with incomplete utilization of the sugar. Application of polypropylene glycol 4000 (PPG) as solvent for in situ product removal during the fermentation shows that this is not due to toxicity by the muconic acid produced. CONCLUSIONS: This work has developed an industrial yeast strain able to produce muconic acid from glucose and also with great efficiency from xylose, without any ethanol production, minimal production of PCA and reaching the highest titers in batch fermentation reported up to now. Utilization of higher sugar levels remained conspicuously incomplete. Since this was not due to product inhibition by muconic acid or to loss of viability, an unknown, possibly metabolic bottleneck apparently arises during muconic acid fermentation with high sugar levels and blocks further sugar utilization.

A sustainable wood biorefinery for low-carbon footprint chemicals production.

The profitability and sustainability of future biorefineries are dependent on efficient feedstock use. Therefore, it is essential to valorize lignin when using wood. We have developed an integrated biorefinery that converts 78 weight % (wt %) of birch into xylochemicals. Reductive catalytic fractionation of the wood produces a carbohydrate pulp amenable to bioethanol production and a lignin oil. After extraction of the lignin oil, the crude, unseparated mixture of phenolic monomers is catalytically funneled into 20 wt % of phenol and 9 wt % of propylene (on the basis of lignin weight) by gas-phase hydroprocessing and dealkylation; the residual phenolic oligomers (30 wt %) are used in printing ink as replacements for controversial para-nonylphenol. A techno-economic analysis predicts an economically competitive production process, and a life-cycle assessment estimates a lower carbon dioxide footprint relative to that of fossil-based production.

Classical versus controlled rapid sequence induction and intubation in children with bleeding tonsils (a retrospective audit).

PURPOSE: To determine whether bag-mask ventilation between induction of anaesthesia and tracheal intubation in children with post-tonsillectomy bleeding reduces the incidence of hypoxaemia and difficult direct laryngoscopy without increasing perioperative respiratory complications. METHODS: Medical records, anaesthesia protocols and vital sign data were analysed from February 2005 to March 2017 for patients undergoing anaesthesia for surgical revision of bleeding tonsils. Type of rapid sequence induction and intubation (RSII; classical, ie, apnoeic, vs controlled, ie, with gentle bag-mask ventilation) was noted. Primary outcomes were incidence of moderate and severe hypoxaemia, grade of direct laryngoscopic views as well as occurrence of noted tracheal intubation difficulties. Haemodynamic alterations during RSII and perioperative adverse events such as noted gastric regurgitation, pulmonary aspiration and perioperative pulmonary morbidity were also recorded. RESULTS: A classical RSII was performed for 22 surgical revisions in 22 children and a controlled RSII was used for 88 surgical revisions in 81 children. Patients undergoing controlled RSII had less incidence of severe hypoxaemia (1 vs 3; P = .025), better direct laryngoscopic views (P = .048) and less hypertension (5 vs 9; P < .001) than those patients managed by classical RSII. No tracheal intubation difficulties occurred. There was no significant perioperative pulmonary morbidity reported in either group. CONCLUSIONS: Controlled RSII had advantages over classical RSII in children with post-tonsillectomy bleeding and may become a strategic option in these patients to avoid hypoxaemia, difficult laryngoscopy and hypertension during induction of anaesthesia and tracheal intubation. Bag-mask ventilation in patients with bleeding tonsils did not lead to pulmonary morbidity.

Childhood Stroke: Awareness, Interest, and Knowledge Among the Pediatric Community.

Objective: Acute childhood stroke is an emergency requiring a high level of awareness among first-line healthcare providers. This survey serves as an indicator of the awareness of, the interest in, and knowledge of childhood stroke of German pediatricians. Methods: Thousand six hundred and ninety-seven physicians of pediatric in- and outpatient facilities in Bavaria, Germany, were invited via email to an online-survey about childhood stroke. Results: The overall participation rate was 14%. Forty-six percent of participants considered a diagnosis of childhood stroke at least once during the past year, and 47% provide care for patients who have suffered childhood stroke. The acronym FAST (Face-Arm-Speech-Time-Test) was correctly cited in 27% of the questionnaires. Most commonly quoted symptoms of childhood stroke were hemiparesis (90%), speech disorder (58%), seizure (44%), headache (40%), and impaired consciousness (33%). Migraine (63%), seizure (39%), and infections of the brain (31%) were most frequently named as stroke mimics. Main diagnostic measures indicated were magnetic resonance imaging (MRI) (96%) and computer tomography (CT) (55%). Main therapeutic strategies were thrombolysis (80%), anticoagulation (41%), neuroprotective measures, and thrombectomies (15% each). Thirty-nine percent of participants had taken part in training sessions, 61% studied literature, 37% discussed with colleagues, and 25% performed internet research on childhood stroke. Ninety-three percent of participants approve skill enhancement, favoring training sessions (80%), publications (43%), and web based offers (35%). Consent for offering a flyer on the topic to caregivers in facilities was given in 49%. Conclusion: Childhood stroke constitutes a topic of clinical importance to pediatricians. Participants demonstrate a considerable level of comprehension concerning the subject, but room for improvement remains. A multi-modal approach encompassing an elaborate training program, regular educational publications in professional journals, and web based offers could reach a broad range of health care providers. Paired with a public adult and childhood stroke awareness campaign, these efforts could contribute to optimize the care for children suffering from stroke.

Pediatric pulmonology year in review 2017: Part 1.

Pediatric Pulmonology publishes original research, case reports and review articles on topics related to a wide range of children's respiratory disorders. In this article (Part 1 of a series), we summarize the past year's publications in our major topic areas, as well as selected literature in these areas from other journals. In Part 1, we review selected articles on diagnostic testing/endoscopy, respiratory complications of neuromuscular disorders, and rare lung diseases.

Assessment of the multiplex PCR-based assay Unyvero pneumonia application for detection of bacterial pathogens and antibiotic resistance genes in children and neonates.

BACKGROUND: Pneumonia is a major healthcare problem. Rapid pathogen identification is critical, but often delayed due to the duration of culturing. Early, broad antibacterial therapy might lead to false-negative culture findings and eventually to the development of antibiotic resistances. We aimed to assess the accuracy of the new application Unyvero P50 based on multiplex PCR to detect bacterial pathogens in respiratory specimens from children and neonates. METHODS: In this prospective study, bronchoalveolar lavage fluids, tracheal aspirates, or pleural fluids from neonates and children were analyzed by both traditional culture methods and Unyvero multiplex PCR. RESULTS: We analyzed specimens from 79 patients with a median age of 1.8 (range 0.01-20.1). Overall, Unyvero yielded a sensitivity of 73.1% and a specificity of 97.9% compared to culture methods. Best results were observed for non-fermenting bacteria, for which sensitivity of Unyvero was 90% and specificity 97.3%, while rates were lower for Gram-positive bacteria (46.2 and 93.9%, respectively). For resistance genes, we observed a concordance with antibiogram of 75% for those specimens in which there was a cultural correlate. CONCLUSIONS: Unyvero is a fast and easy-to-use tool that might provide additional information for clinical decision making, especially in neonates and in the setting of nosocomial pneumonia. Sensitivity of the PCR for Gram-positive bacteria and important resistance genes must be improved before this application can be widely recommended.

ERS statement: interventional bronchoscopy in children.

Paediatric airway endoscopy is accepted as a diagnostic and therapeutic procedure, with an expanding number of indications and applications in children. The aim of this European Respiratory Society task force was to produce a statement on interventional bronchoscopy in children, describing the evidence available at present and current clinical practice, and identifying areas deserving further investigation. The multidisciplinary task force panel performed a systematic review of the literature, focusing on whole lung lavage, transbronchial and endobronchial biopsy, transbronchial needle aspiration with endobronchial ultrasound, foreign body extraction, balloon dilation and occlusion, laser-assisted procedures, usage of airway stents, microdebriders, cryotherapy, endoscopic intubation, application of drugs and other liquids, and caregiver perspectives. There is a scarcity of published evidence in this field, and in many cases the task force had to resort to the collective clinical experience of the committee to develop this statement. The highlighted gaps in knowledge underline the need for further research and serve as a call to paediatric bronchoscopists to work together in multicentre collaborations, for the benefit of children with airway disorders.

Pediatric Pulmonology year in review 2016: Part 1.

Pediatric Pulmonology continues to publish research and clinical topics related to the entire range of children's respiratory disorders. As we have done annually in recent years, we here summarize the past year's publications in our major topic areas, as well as selected literature in these areas from other core journals relevant to our discipline. This review (Part 1) covers selected articles on sleep, diagnostic testing/endoscopy, respiratory complications of neuromuscular disorders, and rare lung diseases.

Foreign body removal in children: Recommendations versus real life-A survey of current clinical management in Germany.

BACKGROUND: Task forces of the European Respiratory Society (ERS, 2003) and the American Thoracic Society (ATS, 2015) both recommend rigid bronchoscopy for foreign body removal in children. However, there is an increasing number of publications recommending flexible bronchoscopy as primary method for foreign body removal in children. METHODS: We therefore initiated a nationwide survey, investigating the routinely used method of foreign body removal in children in different centers in Germany. RESULTS: In total, 259 centers took part in the survey. Twenty percent used flexible bronchoscopy as primary method of choice for foreign body removal. Of note, only 40% of the respondents reported that they had attended formal training courses in flexible bronchoscopy, 15% in rigid bronchoscopy, and 42% had never attended a formal training. Twenty-five percent indicated that they had already encountered an emergency situation during or after foreign body removal, requiring intensive care. CONCLUSION: Published data shows that rigid bronchoscopy involves fewer complications and is more successful in foreign body removal in children. It is consequently questionable, why 20% of the medical centers report a preference for the flexible method. One reason might be the poor availability of rigid bronchoscopy and the difficulty gaining sufficient expertise in rigid bronchoscopy in Germany. Pediatr Pulmonol. 2017;52:656-661. © 2016 Wiley Periodicals, Inc.

[The remains of the day: A working day in a university children's hospital]. / Was vom Tage übrig bleibt ­ Arbeitsalltag einer Universitätsmedizin für Kinder und Jugendliche.

BACKGROUND: Limited time available for direct patient contact and a lot of time required for administrative duties have been reported by physicians working in adult medicine. OBJECTIVE: To characterize the typical daily work routine in a major pediatric university hospital. MATERIALS AND METHODS: A self-administered questionnaire was completed by physicians in the University Children's Hospital, Munich. The questionnaire captured the time spent on direct patient contact and on administrative tasks as well as the physicians' clinical experience and the location where the respective work was actually carried out (inpatient ward, outpatient emergency department, specialized outpatient clinic or department for developmental medicine). RESULTS: Most physicians (91.7 %) reported daily working hours beyond the regular schedule of 8.5hours. The proportion of time dedicated to direct patient contact was 31.2 % (95 % confidence interval: 25.2-37.1). Considering the number of patients in the work units, the average amount of time available for each individual patient varied between 14 minutes in the pediatric ward and 52 minutes in the department for developmental medicine. The reported times spent on patient contact did not significantly differ between physicians with > 5 years and those with ≤ 5 years of clinical experience. CONCLUSION: Although physicians in a university pediatric hospital work long daily hours, only restricted time is available for direct patient contact defined as physical examination of the child and face-to-face communication with patients and families.

Pediatric pulmonology year in review 2015: Part 3.

Our journal covers a broad range of research and scholarly topics related to children's respiratory disorders. For updated perspectives on the rapidly expanding knowledge in our field, we will summarize the past year's publications in our major topic areas, as well as selected publications in these areas from the core clinical journal literature outside our own pages. The current review (Part 3) covers articles on asthma, diagnostic testing/endoscopy, respiratory complications of neuromuscular disorders, and rare lung diseases. Pediatr Pulmonol. 2016;51:747-753. © 2016 Wiley Periodicals, Inc.

Pediatric Pulmonology year in review 2014: Part 1.

Our discipline and our journal cover an extremely broad range of research and scholarly topics related to children's respiratory disorders. To better meet the needs of our readership for updated perspectives on the rapidly expanding knowledge in our field, we here summarize the past year's publications in our major topic areas, as well as selected publications in these areas from the core clinical journal literature outside our own pages.

Prevalence and characteristics of tracheal cobblestoning in children.

BACKGROUND: Tracheal follicular pattern or so-called tracheal cobblestoning is a poorly described entity in the literature and is depicted as a nodular or lumpy appearance of the tracheal wall mucosa suggesting tracheal irritation from factors like gastro-esophageal reflux (GERD) or pulmonary infection. The aim of the present study was to investigate the prevalence and characteristics of tracheal cobblestones in a large pediatric population. METHODS: A large database of rigid tracheoscopies recorded in children (0-6 years of age) undergoing general anesthesia with planned tracheal intubation for elective surgical procedures was retrospectively analyzed. Tracheoscopy records were reviewed by five pediatric airway experts (authors 3-7). Data were compared using the Mann-Whitney test, chi-square or Fisher exact test as appropriate (P < 0.05). RESULTS: A total of 971 rigid tracheoscopy records were analyzed. The median age of the patients was 3.3 years (range 0.4-6.0 yrs). Cobblestones were present in 377 out of 971 patients (38.8%) with a male to female prevalence of 254 (40.6%)/123 (35.5%). None of the children under four months of age showed the presence of cobblestones. The prevalence of cobblestones was significantly less in patients under 3 years of age compared to over 3 years (P < 0.01). There was no association between prevalence of cobblestones and GERD, current or recent respiratory infection or concomitant enlarged tonsils. CONCLUSION: The prevalence of tracheal cobblestones in otherwise healthy children is high and is not associated with GERD or respiratory infection. The gender and age related differences are novel interesting findings that require further investigations.

Endobronchial lesions caused by nontuberculous mycobacteria in apparently healthy pediatric patients.

Pulmonary disease caused by nontuberculous mycobacteria in healthy children is rare, and its pathogenesis is unknown in most cases and standardized treatment is lacking. Here, we report various endobronchial manifestations in 5 patients including hitherto undescribed diffuse tracheobronchial granulomas in 2 patients. Bronchoscopic debulking was performed in all patients and tuberculostatic treatment in 4. All patients including 1 without tuberculostatic treatment showed remission.

The prevalence of tracheal bronchus in pediatric patients undergoing rigid bronchoscopy.

BACKGROUND: Tracheal bronchus (TB) is defined as an abnormal bronchus that originates directly from the lateral wall of the trachea above the carina and goes towards the upper lobe territory of the lung. We analyzed rigid endoscopies of the trachea in children to determine the incidence and characteristics of TB. METHODS: In total, 1021 rigid endoscopies of the trachea recorded from children aged 0 to 6 years were analyzed. Endoscopic examination was performed from supraglottic region to carina using a 0-degree Hopkins rod-lens telescope. Patients with a TB were identified and the site of origin of the TB and its level above the carina was noted. Data of the identified patients was reviewed for the presence of preoperative airway findings such as stridor, upper lobe pneumonia and wheezing or atelectasis, other congenital anomalies, and intraoperative complications. RESULTS: TB was detected in 11 (1.06%) of 1021 upper airway endoscopic examinations. All originated from the right lateral wall of the trachea. Six children had retained secretions in the TB, and 3 children had perioperative airway problems unrelated to the TB. One child showed right main stem bronchus narrowing as seen at the true carina, in the presence of a TB. All the children with TB exhibited at least 1 additional congenital anomaly at birth besides TB. CONCLUSIONS: TB is a relatively common congenital endoscopic lower airway anomaly in childhood, which is itself rarely symptomatic, but almost always coexists with other congenital anomalies.