Central airway obstruction: is it time to move forward?

INTRODUCTION: Central airway obstruction (CAO) represents a pathological condition that can lead to airflow limitation of the trachea, main stem bronchi, bronchus intermedius or lobar bronchus. MAIN BODY: It is a common clinical situation consensually considered under-diagnosed. Management of patients with CAO can be difficult and deciding on the best treatment approach represents a medical challenge. This work intends to review CAO classifications, causes, treatments and its therapeutic limitations, approaching benign and malign presentations. Three illustrative cases are further presented, supporting the clinical problem under review. CONCLUSION: Management of CAO still remains a challenge. The available options are not always effective nor free from complications. A new generation of costume-tailored airway stents, associated with stem cell-based therapy, could be an option in specific clinical situations.

Diagnosis of Retrolingual Obstruction during Drug-Induced Sleep Endoscopy versus Polysomnography with Nasopharyngeal Tube in Patients with Obstructive Sleep Apnea.

OBJECTIVE: To compare the retrolingual obstruction during drug-induced sleep endoscopy (DISE) with the retrolingual obstruction during polysomnography with nasopharyngeal tube (NPT-PSG). METHODS: A cross-sectional study of 77 consecutive patients with moderate and severe obstructive sleep apnea (OSA) was conducted. After 15 patients were excluded from the study for not completing DISE or NPT-PSG successfully, 62 patients were included in this study. Retrolingual sites of obstruction grade 2 determined by DISE according to the VOTE (velum, oropharynx lateral wall, tongue base, and epiglottis) classification were considered as retrolingual obstruction, while apnea-hypopnea index (AHI) ≥ 15 events/hour determined by NPT-PSG was considered as retrolingual obstruction. The extent of agreement between DISE and NPT-PSG findings was evaluated using unweighted Cohen's kappa test. RESULTS: The 62 study participants (11 moderate OSA, 51 severe OSA) had a mean (SD) age of 39.8 (9.9) years, and 58 (94%) were men. No statistically significant differences between included and excluded patients were observed in patient characteristics. The extent of agreement in retrolingual obstruction between DISE and NPT-PSG was 80.6% (Cohen k = 0.612; 95% CI, 0.415-0.807). CONCLUSION: Retrolingual obstruction requiring treatment showed good agreement between DISE and NPT-PSG, suggesting that NPT-PSG may also be a reliable method to assess the retrolingual obstruction.

Drug-induced sleep endoscopy in children. / Exploración videoendoscópica bajo sueño inducido en niños.

This document is intended as a guide for Spanish ENT specialists who want to perform drug-induced sleep endoscopy. Indications, sedation method and important findings are discussed to unify criteria and methodology.

Drug-induced sleep endoscopy. / La endoscopia del sueño inducido.

This document introduces drug-induced sleep endoscopy to the specialist treating sleep breathing disorders and is intended as a guide for those willing to perform the procedure so that it can be reproducible.

Effect of the Application of the Global Lung Initiative 2012 Spirometry Reference Equation on the Diagnosing and Classifying Degree of Airway Obstruction in Thai Adults Aged 40 to 80 Years Old.

Background and objective: Changing to a different spirometry reference equation can result in misinterpretation of spirometric findings. Currently, there is limited data about any discordance between the interpretations of airway obstruction (AO) using the Global Lungs Initiative (GLI) 2012 and the currently employed Thai reference equations (Siriraj) in Thai adults. Therefore, this study aimed to determine differences in diagnosis around AO and classification of the severity of AO using the GLI2012 and Siriraj reference equations in Thai adults. Materials and Methods: We analyzed spirometric results from Thai adults aged 40-80 years old (n = 2084), which were collected at the Lung Health Center, Maharaj Nakorn Chiang Mai Hospital, Chiang Mai, Thailand between January 2005 and December 2015. The diagnoses concerning the AO were interpreted using the GLI2012 and Siriraj reference equations. The severity of AO in each case was classified into five grades, including mild, moderate, moderately severe, severe, or very severe. McNemar's test was used to analyze differences in diagnosis of AO and classification of the level of severity. The Kappa statistic was used to determine agreements of diagnosis of AO and classification of severity between the two reference equations. Results: There were significant differences in both diagnosis of AO and their classifying severity level between the two reference equations (p-value < 0.001). However, the levels of agreement between the two reference equations were moderate to very good in different age and sex groups (Kappa values ranged from 0.62 to 0.78 for the diagnosis of AO and 0.54 to 0.89 for the classification of severity). Conclusions: Changing from the Siriraj to the GLI2012 reference equations underestimates the proportion of airway obstruction in Thai adults.

New classifications for Life-threatening foreign body airway obstruction.

INTRODUCTION: Foreign body airway obstruction (FBAO) is a common medical emergency; however, few studies of life-threatening FBAO have been reported and no standard classification system is available. METHODS: We retrospectively evaluated patients who presented to the emergency departments of two hospitals and were diagnosed with FBAO. The primary outcome was cerebral performance category (CPC) score at discharge. To establish a new classification system for FBAO, FBAO was classified into three types based on the anatomical and physiological characteristics of the obstructed airway. RESULTS: A total of 137 patients were enrolled. Median age was 79.0 years. The most common cause of FBAO was meat, followed by bread, rice cake, and rice. Of all patients, 65.7% suffered cardiac arrest and 51.1% died. In contrast, 28.5% had favorable neurological outcomes, defined as CPC 1 and 2. Upper airway obstruction (type 1) was the most common (type 1, 78.1%), while trachea and/or bilateral main bronchus obstruction (type 2, 12.4%) showed significantly higher mortality than type 1 obstruction (82.4% vs 47.7%, P = 0.0078). Patients with unilateral bronchus and/or distal bronchus obstruction (type 3, 9.5%) were significantly more likely to consume a dysphagia diet than type 1 patients (23.1% vs 0%, P < 0.0001). CONCLUSION: The majority of patients with life-threatening FBAO were elderly and had poor neurological outcomes. Our new classification system divides FBAO into three types, and revealed that mortality was significantly higher with type 2 than type 1 obstruction. This classification system may improve the management of patients with FBAO and assessment of patient outcomes.

Performance of new spirometry reference values in preoperative assessment of lung function.

BACKGROUND: Pulmonary function is not routinely assessed in patients without respiratory disease and symptoms before surgery, even if they are smokers. We aimed to check whether the new spirometric reference values of the worldwide Global Lung Initiative (GLI) affected the preoperative assessment of lung function in allegedly lung-healthy patients compared with the still commonly used old predicted values. METHODS: Two hundred nineteen allegedly lung-healthy non-smokers, past and current smokers were examined by spirometry before elective surgery. The obtained values of forced expiratory volume in 1 second (FEV1 ), forced vital capacity (FVC) and FEV1 /FVC were transformed into z-scores according to the GLI guidelines. A comparison between the new and old reference values was performed. FEV1 was used for the grading of airway obstruction. RESULTS: One hundred eighty-three subjects performed the ventilation manoeuvre according to the GLI recommendations and were analysed. Most non-smokers and past smokers met the new references ranges for spirometric values. Only z-scores of FEV1 /FVC distinguished among all three patient groups, FEV1 between smokers and the other two groups and FVC did not discriminate the groups, irrespective of the reference values used. Airway obstruction was identified in 24% of asymptomatic smokers by z-scores of FEV1 /FVC but in only 14% by the old predicted values. In elderly smokers (>60 years), the corresponding values rose to 50% and 30%. Old predicted values of FEV1 underestimated the degree of airway obstruction mainly in middle-aged smokers. CONCLUSION: Allegedly lung-healthy current smokers showed a higher proportion of preoperatively reduced lung function when z-scores were used, especially in elderly subjects.

Noninvasive Ventilation as a Temporizing Measure in Critical Fixed Central Airway Obstruction: A Case Report.

BACKGROUND: Critical central airway obstruction (CAO) requires emergent airway intervention, but current guidelines lack specific recommendations for airway management in the emergency department (ED) while awaiting rigid bronchoscopy. There are few reports of the use of noninvasive ventilation (NIV) in tracheomalacia, but its use as a temporizing treatment option in fixed, malignant CAO has not, to the best of our knowledge, been reported. CASE REPORT: An 84-year-old woman presented to the ED in respiratory distress, too breathless to speak and using her accessory muscles of respiration, with bilateral rhonchi throughout the lung fields. Point-of-care arterial blood gas revealed severe hypercapnia, and NIV was initiated to treat a presumed bronchitis with hypercapnic respiratory failure. Chest radiography revealed a paratracheal mass with tracheal deviation and compression. A diagnosis of critical CAO was made. While arranging for rigid bronchoscopic stenting, the patient was kept on NIV to good effect. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Recommendations for emergent treatment of life-threatening, critical CAO before bronchoscopic intervention are not well established. Furthermore, reports of NIV use in CAO are rare. We suggest that emergency physicians consider NIV as a temporizing measure for critical CAO while awaiting availability of bronchoscopy.

Comparative prevalence of co-morbidities in smoking and non-smoking asthma patients with incomplete reversibility of airway obstruction, non-smoking asthma patients with complete reversibility of airway obstruction and COPD patients.

BACKGROUND: Asthma with incomplete reversibility of airway obstruction (IRAO) may often be associated to smoking-induced changes. Nevertheless, a high proportion of patients showing IRAO have never smoked. These patients with IRAO often share features of patients with chronic obstructive pulmonary disease (COPD). Although IRAO is still a poorly defined condition, it has been associated with a higher morbidity and mortality than asthma with complete reversibility of airway obstruction (CRAO) or even COPD alone. A high prevalence of comorbidities could contribute to the reported poorer clinical outcome in IRAO, in comparison to CRAO or COPD alone. AIM: To determine the prevalence of past and current comorbidities in IRAO patients compared to patients with CRAO or COPD. METHODS: This was a retrospective, cross-sectional study. Demographic data, clinical characteristics and 36 predetermined comorbidities documented from self-report and chart review, were recorded from smoking-associated IRAO (S-IRAO), non-smoking IRAO (NS-IRAO), CRAO and COPD patients. RESULTS: A total of 199 patients were included in the final analysis (111F/88M, mean (±SD) age of 63 ± 10 years). The CRAO group had more comorbidities than the three other groups, but this difference was significant only with the NS-IRAO group (P = 0.04). For most comorbidities, the prevalence of comorbidities in both IRAO sub-groups was intermediate between CRAO and COPD, with significant differences between S-IRAO and NS-IRAO only for hypertension (P = 0.03), nasal polyps (P = 0.002) and pneumonia (P = 0.04). Typical asthma-associated comorbidities tended to be more prevalent in NS-IRAO patients and COPD-associated comorbidities in S-IRAO patients. CONCLUSION: In this study, the prevalence of comorbidities was not superior in patients with IRAO, compared to those with CRAO or COPD alone. The prevalence of comorbidities in the two main types of IRAO patients reflects exposure to cigarette smoke and asthma-related mechanisms.

Comparison of level and degree of upper airway obstruction by Müller's maneuver and drug-induced sleep endoscopy in obstructive sleep apnea patients.

OBJECTIVE: This study aimed to compare and analyze the level and degree of observed upper airway obstruction in patients with obstructive sleep apnea (OSA) using Müller's maneuver (MM) and drug-induced sleep endoscopy (DISE). We sought to find a method for evaluating the upper airway that could be used to determine surgical sites. METHODS: This study included 80 OSA patients who visited Kyung Hee Medical Center and underwent polysomnography (PSG) from March 2013 to March 2014. Obstructive levels observed by MM were classified into retropalatal level, or the lateral wall and retroglossal level. These levels were compared with those determined by DISE through the VOTE classification. RESULTS: Based on the results of MM and DISE, lateral wall and retropalatal level obstructions showed relatively high conformity, while retroglossal level obstruction exhibited considerable differences. When evaluated at each level, patients with obstruction on MM also showed partial or complete obstruction on DISE at same level, and patients with no obstruction on DISE also showed no obstruction on MM at same level. CONCLUSION: Both examination methods revealed the same obstruction levels in all cases except epiglottic level, but there were some differences in obstructive degree. MM is capable of detecting obstruction levels in the upper airway and can be used to determine surgical sites in cases when DISE cannot be used due to a patient's condition or a clinic's circumstances.

Severity of clinical manifestations and laryngeal exposure difficulty predicted by glossoptosis endoscopic grades in Robin sequence patients.

OBJECTIVE: To evaluate the performance of two glossoptosis airway obstruction classifications in predicting symptom severity and laryngeal exposure difficulty in Robin Sequence (RS) patients. SETTING: Public tertiary hospital otolaryngology section (Hospital de Clínicas de Porto Alegre - HCPA). PATIENTS: All RS patients diagnosed at HCPA from October 2012 to February 2015 were enrolled, a total of 58 individuals. They were classified in isolated RS, RS-Plus and syndromic RS. INTERVENTION: Patients were submitted to sleep endoscopy and a score was attributed according to Yellon and de Sousa by a blinded researcher. Symptom severity evaluation was performed as defined by Cole classification. MAIN OUTCOME MEASURE: Association between endoscopic findings and clinical symptoms severity and laryngeal exposure difficulty. RESULTS: Twenty four patients were identified as isolated RS (41.4%), 19 patients presented as RS-Plus (32.7%) and 15 patients had well defined diagnosed syndromes (25.9%). Concomitant airway anomalies were found in 18 patients (31%). Specifically 17.4% in isolated RS, 55.6% in RS- Plus and 28.6% in the syndromic group had such anomalies (P = 0,03). Probability of presenting severe clinical symptoms as graded by Cole was higher in grade 3 Yellon classification (68.4%, P = 0.012) and in moderate and severe de Sousa classification (61.5% and 62.5%, respectively, P = 0.015) than in milder grades of obstruction. This findings were considered significant even after controlling for patient age. Laryngeal exposure difficulty was correlated with de Sousa and Yellon (Rho = 0,41 and Rho = 0,43, respectively; P < 0,05). CONCLUSION: Patients with higher degrees of obstruction in sleep endoscopy had a higher probability of presenting a more severe clinical manifestation and a more difficult laryngeal exposure. Since the number of patients included in this study was small for subgroup analyses, it is not clear if this association is restricted to a specific group of RS.

Tiotropium improves lung function, exacerbation rate, and asthma control, independent of baseline characteristics including age, degree of airway obstruction, and allergic status.

BACKGROUND: Many patients with asthma remain symptomatic despite treatment with inhaled corticosteroids (ICS) with or without long-acting ß2-agonists (LABAs). Tiotropium add-on to ICS plus a LABA has been shown to improve lung function and reduce exacerbation risk in patients with symptomatic asthma. OBJECTIVE: To determine whether the efficacy of tiotropium add-on therapy is dependent on patients' baseline characteristics. METHODS: Two randomized, double-blind, parallel-group, twin trials (NCT00772538 and NCT00776984) of once-daily tiotropium Respimat(®) 5 µg add-on to ICS plus a LABA were performed in parallel in patients with severe symptomatic asthma. Exploratory subgroup analyses of peak forced expiratory volume in 1 s (FEV1), trough FEV1, time to first severe exacerbation, time to first episode of asthma worsening, and seven-question Asthma Control Questionnaire responder rate were performed to determine whether results were influenced by baseline characteristics. RESULTS: 912 patients were randomized: 456 received tiotropium and 456 received placebo. Tiotropium improved lung function, reduced the risk of asthma exacerbations and asthma worsening, and improved asthma symptom control, compared with placebo, independent of baseline characteristics including gender, age, body mass index, disease duration, age at asthma onset, and FEV1 % predicted at screening and reversibility. CONCLUSION: Once-daily tiotropium 5 µg compared with placebo improved lung function, reduced the risk of asthma exacerbations and asthma worsening, and improved asthma symptom control, independent of a broad range of baseline characteristics, as add-on to ICS plus LABAs in patients with severe symptomatic asthma. TRIAL REGISTRY: ClinicalTrials.gov; numbers NCT00772538 and NCT00776984 URL: www.clinicaltrials.gov.

The asthma-COPD overlap syndrome: do we really need another syndrome in the already complex matrix of airway disease?

The term asthma-COPD overlap syndrome (ACOS) is one of multiple terms used to describe patients with characteristics of both COPD and asthma, representing ~20% of patients with obstructive airway diseases. The recognition of both sets of morbidities in patients is important to guide practical treatment decisions. It is widely recognized that patients with COPD and coexisting asthma present with a higher disease burden, despite the conceptual expectation that the "reversible" or "treatable" component of asthma would allow for more effective management and better outcomes. However, subcategorization into terms such as ACOS is complicated by the vast spectrum of heterogeneity that is encapsulated by asthma and COPD, resulting in different clinical clusters. In this review, we discuss the possibility that these different clusters are suboptimally described by the umbrella term "ACOS", as this additional categorization may lead to clinical confusion and potential inappropriate use of resources. We suggest that a more clinically relevant approach would be to recognize the extreme variability and the numerous phenotypes encompassed within obstructive airway diseases, with various degrees of overlapping in individual patients. In addition, we discuss some of the evidence to be considered when making practical decisions on the treatment of patients with overlapping characteristics between COPD and asthma, as well as the potential options for phenotype and biomarker-driven management of airway disease with the aim of providing more personalized treatment for patients. Finally, we highlight the need for more evidence in patients with overlapping disease characteristics and to facilitate better characterization of potential treatment responders.

Drug-induced sedation endoscopy versus clinical exploration for the diagnosis of severe upper airway obstruction in OSAHS patients.

BACKGROUND: Identifying the sites of obstruction of the upper airway in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) is paramount for surgical planning. The aim of this study is to compare wake physical exam findings to the ones obtained during drug-induced sedation endoscopy (DISE) in the diagnosis of severe collapse of the upper airway in OSAHS patients. METHODS: A retrospective chart review of OSAHS patients who underwent DISE at our institution during the 2006-2010 period was conducted. All the patients had previously undergone a physical examination that included modified Mallampati index (MMI), the Müller maneuver (MM), and the Friedman staging system. Level and severity of airway collapse were evaluated. A severe collapse was attributed to obstructions equal or greater than 75 % of the airway. RESULTS: A total of 138 patients were included in the study. The incidence of severe airway collapse was compared between DISE and MM; at retropalatal level, no significant difference was found. At retrolingual level, 69 % of patients had severe collapse with DISE in comparison to a 28 % with the MM (p < 0.05). No relationship was found either with the MMI or with the Friedman staging system when compared to the incidence of severe retrolingual collapse diagnosed by DISE. Concordance was low between awake and DISE exploration in both retropalatal and retroglossal level. CONCLUSION: The Müller maneuver underestimates tongue base severe obstruction diagnosis when compared to that obtained after DISE in OSAHS patients. The wake patient exploration does not accurately correlate to DISE exploration.

[Comparison of the dental measurements according to the obstructive character of the tonsils]. / Comparaison des mensurations d'arcades selon le caractère obstructif des amygdales palatines.

INTRODUCTION: The role of obstructive tonsils in dental arches abnormalities is widely discussed in the literature but remains controversial. Data on the probable relationship between obstructive tonsils and the presence of these orthodontic abnormalities are subjective. The objective of this study is to quantify the relationship between the obstructive character of the tonsils and the dental arches measurements. MATERIALS AND METHODS: A cross-sectional study was performed in children aged between 6 to 12 years divided into 2 groups (A and B) according to the obstructive character of the tonsils. Dental intra- and inter-arches measurements are recorded on each child. Data is analyzed using SPSS 20.0 for Windows. A t Student and chi square tests are respectively used to compare quantitative and qualitative variables according to the obstructive character of the tonsils. The level of significance is fixed at p = 0.05. RESULTS: The upper dental arch depth is significantly more important in subjects with obstructive tonsils (group B). Dental arches widths are significantly more important in subjects without obstructive tonsils (group A). Group B subjects are significantly more likely to have class II malocclusions, open bite and posterior cross bite with mandibular lateral deviation than group A subjects. CONCLUSION: Early evaluation of children with obstructive tonsils can prevent dental intra- and inter-arches abnormalities caused by upper airway obstruction. Thus late and more aggressive treatments which are not always as efficient as when they were performed during childhood will be avoided.

Craniofacial skeletal pattern: is it really correlated with the degree of adenoid obstruction?

OBJECTIVE: The aim of this study was to compare the cephalometric pattern of children with and without adenoid obstruction. METHODS: The sample comprised 100 children aged between four and 14 years old, both males and females, subjected to cephalometric examination for sagittal and vertical skeletal analysis. The sample also underwent nasofiberendoscopic examination intended to objectively assess the degree of adenoid obstruction. RESULTS: The individuals presented tendencies towards vertical craniofacial growth, convex profile and mandibular retrusion. However, there were no differences between obstructive and non-obstructive patients concerning all cephalometric variables. Correlations between skeletal parameters and the percentage of adenoid obstruction were either low or not significant. CONCLUSIONS: Results suggest that specific craniofacial patterns, such as Class II and hyperdivergency, might not be associated with adenoid hypertrophy.

ERS/ELS/ACCP 2013 international consensus conference nomenclature on inducible laryngeal obstructions.

Individuals reporting episodes of breathing problems caused by re-occurring variable airflow obstructions in the larynx have been described in an increasing number of publications, with more than 40 different terms being used without consensus on definitions. This lack of an international consensus on nomenclature is a serious obstacle for the development of the area, as knowledge from different centres cannot be matched, pooled or readily utilised by others. Thus, an international Task Force has been created, led by the European Respiratory Society/European Laryngological Society/American College of Chest Physicians. This review describes the methods used to reach an international consensus on the subject and the resulting nomenclature, the 2013 international consensus conference nomenclature.

Classification and implementation of asthma phenotypes in elderly patients.

BACKGROUND: No attempt has yet been made to classify asthma phenotypes in the elderly population. It is essential to clearly identify clinical phenotypes to achieve optimal treatment of elderly patients with asthma. OBJECTIVES: To classify elderly patients with asthma by cluster analysis and developed a way to use the resulting cluster in practice. METHODS: We applied k-means cluster to 872 elderly patients with asthma (aged ≥ 65 years) in a prospective, observational, and multicentered cohort. Acute asthma exacerbation data collected during the prospective follow-up of 2 years was used to evaluate clinical trajectories of these clusters. Subsequently, a decision-tree algorithm was developed to facilitate implementation of these classifications. RESULTS: Four clusters of elderly patients with asthma were identified: (1) long symptom duration and marked airway obstruction, (2) female dominance and normal lung function, (3) smoking male dominance and reduced lung function, and (4) high body mass index and borderline lung function. Cluster grouping was strongly predictive of time to first acute asthma exacerbation (log-rank P = .01). The developed decision-tree algorithm included 2 variables (percentage of predicted forced expiratory volume in 1 second and smoking pack-years), and its efficiency in proper classification was confirmed in the secondary cohort of elderly patients with asthma. CONCLUSIONS: We defined 4 elderly asthma phenotypic clusters with distinct probabilities of future acute exacerbation of asthma. Our simplified decision-tree algorithm can be easily administered in practice to better understand elderly asthma and to identify an exacerbation-prone subgroup of elderly patients with asthma.

Does a patient's Mallampati score predict outcome after maxillomandibular advancement for obstructive sleep apnoea?

The Mallampati airway classification has been used to estimate the success of uvulopalatopharyngoplasty in patients with obstructive sleep apnoea (OSA) but its predictive value in maxillomandibular advancement has not been proved. We aimed to explore the association between preoperative Mallampati scores and surgical outcome after bimaxillary advancement for OSA. We retrospectively analysed data on 50 patients who had maxillofacial operations for OSA at our hospital and stratified them into two groups based on Mallampati scores: high (class III/IV) and low (class I/II). We compared pre- and postoperative apnoea/hypopnoea indices (AHIs), Epworth sleepiness scores, and lowest recorded oxygen saturation in both groups. The postoperative values for all three outcome measures were not significantly different when patients were stratified according to the Mallampati classification (mean (SD) AHI was 41(19) before and 7 (6) after operation in the low group, and 42 (15) before and 9 (7) after in the high group). Success rates (AHI less than 15 postoperatively) were similar in both low and high score groups (p>0.05). Maxillomandibular advancement alleviates obstruction at multiple levels and our study has shown comparable surgical outcomes in both groups. The Mallampati score can be used to optimise patient selection for surgeons considering single-level procedures for OSA. Our study suggests that the Mallampati classification is less useful for the prediction of surgical outcome after maxillomandibular advancement surgery.