Pharyngeal lavage lymphocytosis in patients with obstructive sleep apnea: a preliminary observation

Association of preoperative neutrophil-lymphocyte ratios with the emergence delirium in pediatric patients after tonsillectomy and adenoidectomy: an observational prospective study

PURPOSE

The study aimed to investigate potential risk factors for emergence delirium (ED) in pediatric patients after tonsillectomy and adenoidectomy (T&A).

METHODS

This prospective, single-center observational study enrolled children aged 3-7 years who underwent T&A under general anesthesia. ED was assessed according to DSM-IV or V criteria. Receiver operating characteristic curve analysis was performed to evaluate the predicative and cut-off values of risk factors, including age, preoperative anxiety level, postoperative pain and neutrophil-lymphocyte ratio (NLR) for ED. Univariate and multivariate logistic regression analyses were performed to investigate risk factors for ED.

RESULTS

94 pediatric patients who underwent T&A were enrolled and 19 developed ED (an incidence of 25.3%). Receiver operating characteristic analysis indicated that preoperative NLR was a significant predictor of ED with a cut-off value of 0.8719 and an area under the curve (AUC) of 0.671 (95% confidence interval (CI) 0.546-0.796, P = 0.022). Preoperative NLR (< 0.8719) and postoperative pain were independent risk factors associated with ED (odds ratio: 0.168, 95% CI 0.033-0.858, P = 0.032; odds ratio: 7.298, 95% CI 1.563-34.083, P = 0.011) according to multivariate logistic regression analysis.

CONCLUSIONS

Preoperative NLR level and postoperative pain were independent risk factors for ED in pediatric patients undergoing T&A.

Non-interventional Pilot Study Evaluating the Efficacy and Safety of Lysozymebased Therapy in Patients with Non-infectious Sore Throat

OBJECTIVE

This study aimed to evaluate the efficacy and safety of lysozyme-based oral antiseptic in the therapy of non-infectious sore throat in teachers.

MATERIALS AND METHODS

A non-interventional, prospective, pilot study was conducted with two examinations. The first was performed as part of a general medical examination. If a non-infectious sore throat was confirmed by clinical checkup and all other inclusion and non-exclusion criteria confirmed, patients were offered to be enrolled in the study. After signing the informed consent form, patients were advised to use lysozyme-based lozenges, six times a day, for a period of five days. A telephone call follow-up examination was performed within 24 hours from the therapy completion.

RESULTS

This was a pilot study involving 25 adult patients of both genders. Lysozyme-based lozenges showed positive effects in relieving the symptoms of non-infectious sore throat in teachers. At the same time, the lozenges showed excellent tolerability, and no side effects were reported during the study. 92% of patients confirmed they would take the same medicine again due to the same problem.

CONCLUSION

The results of this "proof-of-concept" study indicated that lysozyme-based antiseptic could be effective and safe in the treatment of non-infectious sore throat in teachers and should be further evaluated as treatment option in this condition.

Extracellular Vesicles from Airway Secretions: New Insights in Lung Diseases

Lung diseases (LD) are one of the most common causes of death worldwide. Although it is known that chronic airway inflammation and excessive tissue repair are processes associated with LD such as asthma, chronic obstructive pulmonary disease (COPD) or idiopathic pulmonary fibrosis (IPF), their specific pathways remain unclear. Extracellular vesicles (EVs) are heterogeneous nanoscale membrane vesicles with an important role in cell-to-cell communication. EVs are present in general biofluids as plasma or urine but also in secretions of the airway as bronchoalveolar lavage fluid (BALF), induced sputum (IS), nasal lavage (NL) or pharyngeal lavage. Alterations of airway EV cargo could be crucial for understanding LD. Airway EVs have shown a role in the pathogenesis of some LD such as eosinophil increase in asthma, the promotion of lung cancer in vitro models in COPD and as biomarkers to distinguishing IPF in patients with diffuse lung diseases. In addition, they also have a promising future as therapeutics for LD. In this review, we focus on the importance of airway secretions in LD, the pivotal role of EVs from those secretions on their pathophysiology and their potential for biomarker discovery.

Smoking history and its relationship with comorbidities in patients with obstructive sleep apnea

INTRODUCTION

Current knowledge on the correlation between smoking and comorbidities associated with obstructive sleep apnea (OSA) is limited. This study evaluated the smoking history of OSA patients and analyzed the association between smoking and OSA comorbidities.

METHODS

Retrospective analysis was performed in newly diagnosed OSA patients in our hospital, a tertiary medical center, from January 2016 to December 2019. In all, 1021 patients were enrolled and divided into two groups, non-smokers (n=796) and current/former smokers (n=225), in order to compare their clinical manifestations and polysomnographic results and to analyze the association between smoking and comorbidities.

RESULTS

Compared with the non-smokers, the current/former smokers had higher Epworth sleepiness scale (ESS) scores (9.3 ± 4.0 vs 8.5 ± 5.1; p<0.05), longer sleep latency (SL) [20.5 (12.3-39.3) vs 18.5 (10.0-34.0) minutes; p<0.05], and a lower nocturnal mean oxygen saturation (91.8 ± 3.6% vs 92.8 ± 3.4%; p<0.001). There was no significant difference in the apnea-hypopnea index (AHI) between the two groups. OSA patients with a history of smoking had significantly increased risk of hypertension (OR=2.09; 95% CI: 1.46- 3.01), chronic obstructive pulmonary disease (COPD) (OR=9.80; 95% CI: 4.73-20.33), gastroesophageal reflux disease (GERD) (OR=1.97; 95% CI: 1.19-3.27), and chronic pharyngitis (OR=1.83; 95% CI: 1.32-2.54).

CONCLUSIONS

No significant association was found between previous smoking history and current OSA severity. OSA patients with a history of smoking had an increased risk of hypertension, COPD, GERD, and chronic pharyngitis.

[Alterations of respiratory resistance in patients with obstructive sleep apnea hypopnea syndrome]

OBJECTIVE

To evaluate the association between the components of airway resistance and severity of obstructive sleep apnea hypopnea syndrome (OSAHS).

METHODS

A total of 234 patients with snoring during sleep underwent full-night polysomnography in our center between January, 2015 and September, 2017. According to the apnea-hypopnea index (AHI) scores, the patients were divided into non-OSAHS group (AHI scores <5), mild or moderate OSAHS group (5-30) group, and severe OSAHS group (>30). The pulmonary function and respiratory resistance of the patients were assessed using spirometry and impulse oscillometry, respectively, and the correlation between the parameters of respiratory resistance and the severity of AHI were analyzed.

RESULTS

The non-OSAHS, mild or moderate OSAHS, and severe OSAHS groups consisted of 31, 90 and 113 patients, respectively. The patients with severe OSAHS had significantly higher levels of respiratory resistance at 5 Hz (R5) and 20 Hz (R20), FEF_50% and MMEF than those in the other two groups (P<0.05). Bivariate correlation analysis identified positive correlations of R5 (r=0.259, P=0.000), R20 (r=0.298, P=0.000) and FEF_50% (r=0.176, P=0.007) with AHI scores of the patients.

CONCLUSION

Patients with OSAHS have increased respiratory resistance in the large airways and compensatory reduction in small airway resistance.

Role of lung volume and airway inflammation in obstructive sleep apnea

Obstructive sleep apnea (OSA) is a prevalent disorder that affects not only the upper airways but also the intrathoracic airways. In this review, we summarize the results of studies on lung function and airway inflammation. We provide evidence that the alterations in intrathoracic airways observed in OSA are not purely consequences of mechanical trauma and oxidative stress during apneic events but have a causal role in the structural changes associated with OSA and increasing severity of this disorder.

Upper airway and systemic inflammation in obstructive sleep apnoea

Obstructive sleep apnoea (OSA) is associated with pharyngeal inflammation, but the coexistence of systemic inflammation is controversial. This study investigated whether local and systemic inflammatory biomarkers are related in patients with OSA. An uncontrolled extension to the study assessed the response to effective treatment.We recruited 89 patients with OSA (apnoea/hypopnoea index (AHI) ≥5 events·h^-1), 28 snorers and 26 healthy controls. Pharyngeal lavage (PHAL) and plasma samples were collected at baseline and after a 1-year follow-up. Inflammatory cells were evaluated by flow cytometry; interleukin (IL)-6, IL-8 and tumour necrosis factor-α were evaluated by immunoassay.In PHAL, CD4⁺ T-cells, IL-6 and IL-8 were higher in OSA patients than in snorers or healthy controls (p<0.05). The AHI correlated with CD4⁺, IL-6 and IL-8 in PHAL (all p-values <0.05). There were no differences in the inflammatory biomarkers in plasma between the study groups and no relationship between plasma and PHAL biomarkers. Biomarkers decreased significantly in PHAL but not in plasma after 1 year of therapy with continuous positive airway pressure or surgery.In patients with OSA, increased levels of inflammatory biomarkers were found in PHAL, which were reduced with effective treatment. No simultaneous increase in plasma inflammatory biomarkers was found.

The impact of chronic intermittent hypoxia on hematopoiesis and the bone marrow microenvironment

Obstructive sleep apnea (OSA) is a highly prevalent sleep-related breathing disorder which is associated with patient morbidity and an elevated risk of developing hypertension and cardiovascular diseases. There is ample evidence for the involvement of bone marrow (BM) cells in the pathophysiology of cardiovascular diseases but a connection between OSA and modulation of the BM microenvironment had not been established. Here, we studied how chronic intermittent hypoxia (CIH) affected hematopoiesis and the BM microenvironment, in a rat model of OSA. We show that CIH followed by normoxia increases the bone marrow hypoxic area, increases the number of multipotent hematopoietic progenitors (CFU assay), promotes erythropoiesis, and increases monocyte counts. In the BM microenvironment of CIH-subjected animals, the number of VE-cadherin-expressing blood vessels, particularly sinusoids, increased, accompanied by increased smooth muscle cell coverage, while vWF-positive vessels decreased. Molecularly, we investigated the expression of endothelial cell-derived genes (angiocrine factors) that could explain the cellular phenotypes. Accordingly, we observed an increase in colony-stimulating factor 1, vascular endothelium growth factor, delta-like 4, and angiopoietin-1 expression. Our data shows that CIH induces vascular remodeling in the BM microenvironment, which modulates hematopoiesis, increasing erythropoiesis, and circulating monocytes. Our study reveals for the first time the effect of CIH in hematopoiesis and suggests that hematopoietic changes may occur in OSA patients.

Tonic stimulation of the pharyngeal mucosa causes pain and a reversible increase of inflammatory mediators

Objective and design

To develop a model of the inflammatory component of non-infectious sore throat using tonic stimulation and quantification of inflammatory mediators in pharyngeal lavage fluid.

Material or subjects

Forty-five healthy volunteers.

Treatment

Cold dry air.

Method

Tonic stimulation of the pharynx was achieved using a constant stream of cold dry air to the back of the throat. Following optimization of stimulation conditions (phase 1), pharyngeal pain, irritation, and swallowing discomfort were assessed using visual analog scales, and the concentration of inflammatory markers were measured in pharyngeal lavage fluid (phase 2).

Results

Optimum conditions for tonic pharyngeal stimulation were cold dry air at 12 °C, relative humidity 20 %, at a flow rate of 12 L/min for 15 min. Analysis of pharyngeal lavage fluid collected 5 min after stimulation showed significant increases in prostaglandin E₂ (P = 0.018), thromboxane B₂ (P < 0.001), and substance P (P < 0.001), but no increase in peptidoleukotriene. When the stimulus was removed, the level of inflammatory markers in pharyngeal lavage fluid returned to baseline by 30 min post-stimulation. These objective measures mirrored subjective pain ratings.

Conclusions

Tonic stimulation of the pharyngeal mucosa with cold dry air causes pain and an increase of inflammatory mediators which are reversible.

Electronic supplementary material

The online version of this article (doi:10.1007/s00011-013-0663-7) contains supplementary material, which is available to authorized users.

Environmental and non-infectious factors in the aetiology of pharyngitis (sore throat)

OBJECTIVES

The aim of this review is to examine the causes, pathophysiology and experimental models of non-infectious pharyngitis (sore throat).

INTRODUCTION

The causes of sore throat can be infectious (viruses, bacteria, and fungi) or non-infectious, although the relative proportion of each is not well documented.

METHODS

A PubMed database search was performed for studies of non-infectious sore throat.

RESULTS AND CONCLUSIONS

Non-infectious causes of sore throat include: physico-chemical factors, such as smoking, snoring, shouting, tracheal intubation, medications, or concomitant illness; and environmental factors including indoor and outdoor air pollutants, temperature and humidity, and hazardous or occupational irritants. The pathophysiology underlying non-infectious sore throat is largely uncharacterised, although neurogenic inflammation looks to be a promising candidate. It is likely that there will be individual disposition factors or the coincidence of more than one irritant with possible--up to now unknown--interactions between them. Therefore, experimental models with defined conditions and objective endpoints are needed. A new model using cold dry air to directly induce pharyngeal irritation in humans, with pharyngeal lavage to measure biomarkers, may provide a useful tool for the study of mechanisms and treatment of non-infectious sore throat.

Pathogenesis of cognitive dysfunction in patients with obstructive sleep apnea: a hypothesis with emphasis on the nucleus tractus solitarius

OSA is characterized by the quintessential triad of intermittent apnea, hypoxia, and hypoxemia due to pharyngeal collapse. This paper highlights the upstream mechanisms that may trigger cognitive decline in OSA. Three interrelated steps underpin cognitive dysfunction in OSA patients. First, several risk factors upregulate peripheral inflammation; these crucial factors promote neuroinflammation, cerebrovascular endothelial dysfunction, and oxidative stress in OSA. Secondly, the neuroinflammation exerts negative impact globally on the CNS, and thirdly, important foci in the neocortex and brainstem are rendered inflamed and dysfunctional. A strong link is known to exist between neuroinflammation and neurodegeneration. A unique perspective delineated here underscores the importance of dysfunctional brainstem nuclei in etiopathogenesis of cognitive decline in OSA patients. Nucleus tractus solitarius (NTS) is the central integration hub for afferents from upper airway (somatosensory/gustatory), respiratory, gastrointestinal, cardiovascular (baroreceptor and chemoreceptor) and other systems. The NTS has an essential role in sympathetic and parasympathetic systems also; it projects to most key brain regions and modulates numerous physiological functions. Inflamed and dysfunctional NTS and other key brainstem nuclei may play a pivotal role in triggering memory and cognitive dysfunction in OSA. Attenuation of upstream factors and amelioration of the NTS dysfunction remain important challenges.