Higher Microbial Abundance and Diversity in Bronchus-Associated Lymphoid Tissue (BALT) Lymphomas than in Non-Cancerous Lung Tissues.

Purpose: It is well known that the majority of the extranodal marginal zone lymphomas of mucosa-associated lymphoid tissues (MALT lymphomas) are associated with microbiota, e.g., gastric MALT lymphoma with Helicobacter pylori. In general, they are very sensitive to low-dose radiotherapy and chemotherapeutic agents. The microbiota profile is not clearly elucidated in bronchus-associated lymphoid tissue (BALT) lymphoma, a rare type of MALT lymphoma in the lung. Thus, this study aimed to clarify the intratumor microbiome in BALT lymphoma using the third-generation NGS method. Materials and Methods: DNAs were extracted from 12 formalin-fixed paraffin-embedded (FFPE) tumor tissues obtained from BALT lymphoma patients diagnosed between 1990 and 2016. 16S rRNA gene was amplified by polymerase chain reaction. Amplicons were sequenced using a Nanopore platform. Next-generation sequencing analysis was performed to assess microbial profiles. For comparison, FFPE specimens from nine non-cancerous lung tissues were also analyzed. Results: Specific bacterial families including Burkholderiaceae, Bacillaceae, and Microbacteriaceae were associated with BALT lymphoma by a linear discriminant analysis effect size approach. Although the number of specimens was limited, BALT lymphomas exhibited significantly higher microbial abundance and diversity with distinct microbial composition patterns and correlation networks than non-cancerous lung tissues. Conclusion: This study provides the first insight into intratumor microbiome in BALT lymphoma using the third-generation NGS method. A distinct microbial composition suggests the presence of a unique tumor microenvironment of BALT lymphoma.

Pediatric Application of Cuffed Endotracheal Tube.

A young child's larynx was formerly believed to be narrowest at the cricoid level, circular in section, and funnel shaped. This supported the routine use of uncuffed endotracheal tubes (ETTs) in young children despite the benefits of cuffed ETTs, such as lower risk for air leakage and aspiration. In the late 1990s, evidence supporting the pediatric use of cuffed tubes emerged largely from anesthesiology studies, while some technical flaws of the tubes remained a concern. Since the 2000s, imaging-based studies have clarified laryngeal anatomy, revealing that it is narrowest at the glottis, elliptical in section, and cylindrical in shape. The update was contemporaneous with technical advances in the design, size, and material of cuffed tubes. The American Heart Association currently recommends the pediatric use of cuffed tubes. In this review, we present the rationale for using cuffed ETTs in young children based on our updated knowledge of pediatric anatomy and technical advances.

Plain Radiographic Analysis of Laryngeal Dimensions in Young Children: Normal versus Croup.

(1) Background: Contrary to a tenet of the funnel-shaped pediatric larynx with the cricoid level being narrowest, recent studies show the glottis and subglottis as the narrowest levels. To locate the functionally narrowest level of the larynx, we reported normal laryngeal dimensions and their croup-related changes in young children. (2) Methods: We reviewed normal plain neck radiographs recorded for the evaluation of minor trauma or foreign bodies in 504 children aged ≤4 years who visited the emergency department from 2016 through 2021. Using computed tomography-based localization of the glottis, we radiographically defined the subglottis and cricoid. At these levels, we measured diameters and calculated cross-sectional areas (CSAs) on the radiographs. The values were compared to the equivalent values of a 1:1 age-matched population with croup. (3) Results: In the study population (n = 401), the narrowest diameter and CSA were observed in the glottis. In detail, the mean anteroposterior/transverse diameters were 9.8/3.4 mm at the glottis, 8.5/5.6 mm at the subglottis, and 7.4/6.8 mm at the cricoid (p < 0.001), respectively. In the same order, the mean CSAs were 26.5, 38.1, and 40.5 mm2 (p < 0.001). All dimensions were narrower in the croup population (p < 0.001). We found croup-related narrowing, namely reductions in the transverse diameter and CSA that were more severe closer to the glottis (p < 0.001), without differences per level in the anteroposterior diameter. (4) Conclusions: This study confirms the glottis as the narrowest level of the larynx in young children. In addition, level-based differences in croup-related narrowing suggest some point between the glottis and subglottis as the functionally narrowest level.

Factors Associated with the Underuse of Sedatives and Neuromuscular Blocking Agents for Pediatric Emergency Endotracheal Intubation in Korea.

PURPOSE: Rapid sequence intubation (RSI) using sedatives and neuromuscular blocking agents (NMBAs) is recommended for pediatric emergency endotracheal intubation (ETI), but is not frequently performed in Korea. This study aimed to verify factors associated with the underuse of RSI medications. MATERIALS AND METHODS: This multicenter retrospective study reviewed patients aged under 18 years who underwent an ETI within 24 hours of arrival at the emergency department between 2016 and 2019. Any cases of ETI during cardiopulmonary resuscitation were excluded. We investigated the characteristics of the patients, intubators, RSI medications, and outcomes. The study cases were classified into no-medication, sedative-only, and sedative-with-NMBA groups. Multivariable logistic regression analysis of RSI medication use was conducted. RESULTS: A total of 334 cases with a median age of 3.4 years were included in this study. Sedatives and NMBAs were used in 63.8% and 32.9%, respectively. In comparing the no-medication (n=121), sedative-only (n=103), and sedative-with-NMBA (n=110) groups, patient age (median; 1.0 year vs. 2.8 years vs. 11.3 years; p<0.001), underlying medical conditions (77.7% vs. 56.3% vs. 36.4%; p<0.001), and pediatricians as intubators (76.9% vs. 54.4% vs. 17.3%; p<0.001) were different. The factors that influenced sedatives with NMBA use were patient age [for a year increment; adjusted odds ratio (aOR), 1.182; 95% confidence interval (CI), 1.120-1.249], no underlying medical conditions (aOR, 2.109; 95% CI, 1.093-4.070), and intubators other than pediatricians (aOR, 5.123; 95% CI, 2.257-11.626). CONCLUSION: RSI accounted for 32.9% of pediatric emergency ETI in Korea. The underuse of RSI medications is associated with younger patient age, underlying medical conditions, and pediatricians as intubators.

Impact of Intubator's Training Level on First-Pass Success of Endotracheal Intubation in Acute Care Settings: A Four-Center Retrospective Study.

(1) Background: First-pass success (FPS) of endotracheal intubation is more challenging in children than in adults. We aimed to identify factors associated with FPS of intubation in acute care settings. (2) Methods: We analyzed data of children aged <10 years who underwent intubation within ≤24 h of arrival at four Korean emergency departments (2016−2019). Variables were compared according to FPS. A logistic regression was performed to quantify the association of factors with FPS. An experienced intubator was defined as a senior resident or a specialist. (3) Results: Of 280 children, 169 (60.4%) had FPS. The children with FPS were older (median age, 23.0 vs. 11.0 months; p = 0.018), were less frequently in their infancy (36.1% vs. 50.5%; p = 0.017), and were less likely to have respiratory compromise (41.4% vs. 55.0%; p = 0.030). The children with FPS tended to be more often intubated by experienced intubators than those without FPS (87.0% vs. 78.4%; p = 0.057). Desaturation was rarer in those with FPS. Factors associated with FPS were experienced intubators (aOR, 1.93; 95% CI, 1.01−3.67) and children's age ≥12 months (1.84; 1.13−3.02). (4) Conclusion: FPS of intubation can be facilitated by deploying or developing clinically competent intubators, particularly for infants, in acute care settings.

Comparison of Base Deficit and Vital Signs as Criteria for Hemorrhagic Shock Classification in Children with Trauma.

PURPOSE: Base deficit (BD) is superior to vital signs in predicting trauma outcomes in adults. The authors aimed to compare BD and vital signs as criteria for the four-tiered hemorrhagic shock classification in children with trauma. MATERIALS AND METHODS: We retrospectively reviewed the data of 1046 injured children who visited a Korean academic hospital from 2010 through 2018. These children were classified separately based on BD (class I, BD ≤2.0 mmol/L; II, 2.1-6.0 mmol/L; III, 6.1-10 mmol/L; and IV, ≥10.1 mmol/L) and vital signs (<13 years: age-adjusted hypotension and tachycardia, and Glasgow Coma Scale; 13-17 years: the 2012 Advanced Trauma Life Support classification). The two methods were compared on a class-by-class basis regarding the outcomes: mortality, early transfusion (overall and massive), and early surgical interventions for the torso or major vessels. RESULTS: In total, 603 children were enrolled, of whom 6.6% died. With the worsening of BD and vital signs, the outcome rates increased stepwise (most p<0.001; only between surgical interventions and vital signs, p=0.035). Mortality more commonly occurred in BD-based class IV than in vital signs-based class IV (58.8% vs. 32.7%, p=0.008). Early transfusion was more commonly performed in BD-based class III than in vital signs-based class III (overall, 73.8% vs. 53.7%, p=0.007; massive, 37.5% vs. 15.8%, p=0.001). No significant differences were found in the rates of early surgical interventions between the two methods. CONCLUSION: BD can be a better predictor of outcomes than vital signs in children with severe hemorrhagic shock.