Overview of Nasal Airway and Nasal Breathing Evaluation.

Several methods are available for evaluating nasal breathing and nasal airflow, as this evaluation may be made from several different perspectives.Physiologic methods for nasal airway evaluation directly measure nasal airflow or nasal airway resistance, while anatomical methods measure nasal airway dimensions. Subjective methods evaluate nasal breathing through several validated patient-reported scales assessing nasal breathing. Computational fluid dynamics evaluates nasal airflow through the analysis of several physics' variables of the nasal airway.Being familiar to these methods is of utmost importance for the nasal surgeon to be able to understand data provided by the different methods and to be able to choose the combination of evaluation methods that will provide the information most relevant to each clinical situation.

Peak Nasal Inspiratory Flow (PNIF) for Nasal Breathing Evaluation.

Measuring nasal airflow and nasal breathing has been a major goal of rhinology. Many objective methods for measuring nasal airflow or nasal airway resistance or dimensions provide valuable data but are time-consuming and require expensive equipment and trained technicians, thus making these methods less practical for clinical practice. Peak nasal inspiratory flow (PNIF) measurement is fast, unexpensive, noninvasive, and able to provide an objective evaluation of nasal airflow in real-time. Unilateral PNIF measurements allow separated evaluation of each side of the nasal airway and may prove particularly useful when clinical assessment detects significant asymmetry between both nasal cavities.PNIF measurements are most useful for assessing changes in nasal airflow achieved by any form of therapy, including surgical treatment of the nasal airway. These measurements generally correlate with other objective methods for nasal airway evaluation, but not unequivocally with patient-reported evaluation of nasal breathing. Nevertheless, as low PNIF values prevent the sensation of a suitable nasal breathing, PNIF measurement may also prove useful to optimize the decision of how to best address patients with complaints of nasal airway obstruction.

[Impact of sinonasal anatomic changes after endoscopic anterior skull base surgery on nasal airflow and air conditioning: a computational fluid dynamics study].

Objective: To analyze the impact of the sinonasal anatomic changes after endonasal endoscopic anterior skull base surgery on the nasal airflow and heating and humidification by computational fluid dynamics (CFD), and to explore the correlation between the postoperative CFD parameters and the subjective symptoms of the patients. Methods: The clinical data in the Rhinology Department of the First Affiliated Hospital of Zhengzhou University from 2016 to 2021 were retrospectively analyzed. The patients received the endoscopic resection of the anterior skull base tumor were selected as the case group, and the adults whose CT scans had no sinonasal abnormalities were chosen as the control group. The CFD simulation was performed on the sinonasal models after reconstructed from the patients' sinus CT images during the post-surgical follow-up. All the patients were asked to complete the Empty Nose Syndrome 6-Item Questionnaire (ENS6Q) to assess the subjective symptoms. The comparison between two independent groups and the correlation analysis were carried out by using the Mann-Whitney U test and the Spearman correlation test in the SPSS 26.0 software. Results: Nineteen patients (including 8 males and 11 females, from 22 to 67 years old) in the case group and 2 patients (a male of 38 years old and a female of 45 years old) in the control group were enrolled in this study. After the anterior skull base surgery, the high-speed airflow moved to the upper part of the nasal cavity, and the lowest temperature shifted upwards on the choana. Comparing with the control group, the ratio of nasal mucosal surface area to nasal ventilation volume in the case group decreased [0.41 (0.40, 0.41) mm-1 vs 0.32 (0.30, 0.38) mm-1; Z=-2.04, P=0.041], the air flow in the upper and middle part of the nasal cavity increased [61.14 (59.78, 62.51)% vs 78.07 (76.22, 94.43)%; Z=-2.28, P=0.023], the nasal resistance decreased [0.024 (0.022, 0.026) Pa·s/ml vs 0.016 (0.009, 0.018) Pa·s/ml; Z=-2.29, P=0.022], the lowest temperature in the middle of the nasal cavity decreased [28.29 (27.23, 29.35)℃ vs 25.06 (24.07, 25.50)℃; Z=-2.28, P=0.023], the nasal heating efficiency decreased [98.74 (97.95, 99.52)% vs 82.16 (80.24, 86.91)%; Z=-2.28, P=0.023], the lowest relative humidity decreased [(79.62 (76.55, 82.69)% vs 73.28 (71.27, 75.05)%; Z=-2.28, P=0.023], and the nasal humidification efficiency decreased [99.50 (97.69, 101.30)% vs 86.09 (79.33, 87.16)%; Z=-2.28, P=0.023]. The ENS6Q total scores of all patients in the case group were less than 11 points. There was a moderate negative correlation between the proportion of the inferior airflow in the post-surgical nasal cavity negatively and the ENS6Q total scores (rs=-0.50, P=0.029). Conclusions: The sinonasal anatomic changes after the endoscopic anterior skull base surgery alter the nasal airflow patterns, reducing the efficiency of nasal heating and humidification. However, the post-surgical occurrence tendency of the empty nose syndrome is weak.

Objective assessment of nasal resistance among electronic cigarette users.

BACKGROUND: Electronic cigarettes have been a popular alternative to tobacco smoking. The effect of tobacco smoking on nasal airway resistance has been investigated before; however, the effect of the aerosol generated by electronic cigarettes is still unknown. This study aimed to evaluate the short-term effects of e-cigarettes on nasal airway resistance. METHODS: Sixty-one participants were recruited into a vapers group and a control group. The vapers group was instructed to smoke for 5 minutes, and their nasal resistance was measured pre-procedure and at 1 and 5 minutes post-procedure. The results were compared between both groups. RESULTS: Repeated measures analysis of variance demonstrated that vaping has no statistically significant effect on total nasal airway resistance. CONCLUSION: Although the differences between both groups were not statistically significant overall, the vapers group showed a reduction in nasal airway resistance in the short term.

Case report: 2 cases of cardiac arrest caused by rhino-cardiac reflex while disinfecting nasal cavity before endonasal transsphenoidal endoscopic pituitary surgery.

BACKGROUND: Trigeminal-cardiac reflex (TCR) is a brainstem vagus reflex that occurs when any center or peripheral branch of the trigeminal nerve was stimulated or operated on. The typical clinical manifestation is sudden bradycardia with or without blood pressure decline. The rhino-cardiac reflex which is one type of TCR is rare in clinical practice. As the rhino-cardiac reflex caused by disinfection of the nasal cavity is very rare, we report these two cases to remind other anesthesiologists to be vigilant to this situation. CASE PRESENTATION: This case report describes two cases of cardiac arrest caused by rhino-cardiac reflex while disinfecting nasal cavity before endoscopic transsphenoidal removal of pituitary adenomas. Their heart rate all dropped suddenly at the very moment of nasal stimulation and recovered quickly after stimulation was stopped and the administration of drugs or cardiac support. CONCLUSION: Although the occurrence of rhino-cardiac reflex is rare, we should pay attention to it in clinical anesthesia. It is necessary to know the risk factors for preventing it. Once it occurs, we should take active and effective rescue measures to avoid serious complications.

Does Nasal Secretion Decrease in Sjögren Syndrome and Does This Affect Nasal Function?

OBJECTIVE: Sjögren syndrome is a systemic inflammatory disease causing gland dysfunction. Few (and contradictory) reports on the mucosal effects of Sjögren syndrome have appeared. Here, we objectively demonstrate nasal dryness in Sjögren syndrome patients and explore the effect of such dryness on olfaction. METHODS: Thirty-four consecutive patients with primary Sjögren syndrome were enrolled in this cross-sectional study. The control group consisted of 21 age- and sex-matched volunteers. Medical histories and nasal findings were recorded. The Connecticut Chemosensory Clinical Research Center test was used to evaluate olfactory function. All subjects underwent mucucociliary clearance analysis (the saccharin test and peak nasal inspiratory flowmetry). The intranasal Schirmer test was used to evaluate the nasal cavity. RESULTS: The nasal Schirmer test scores were 8.4 mm (right) and 8 mm (left) (P = .041, P = .016, respectively, compared to controls). The Chi-squared test revealed significant differences (compared to controls) in nasal dryness (P = .001), postnasal drip (P = .04), and smell (a decrease) (P = .005). Neither olfactory function nor mucociliary clearance differed between the groups. We noted a trend toward a positive correlation between olfactory function and the nasal Schirmer score but statistical significance was not attained. CONCLUSION: The intranasal Schirmer test objectively showed that Sjögren syndrome patients exhibited nasal cavity dryness; this is useful in terms of follow-up. This did not affect olfactory function. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:370-373, 2021.

Measuring vital capacity in amyotrophic lateral sclerosis: Effects of interfaces and reproducibility.

BACKGROUND: Deterioration of vital capacity (VC) in amyotrophic lateral sclerosis (ALS) signifies disease progression and indicates need for non-invasive ventilation. Weak facial muscles consequent to ALS, with resulting poor mouth seal, may interfere with the accuracy of VC measurements. OBJECTIVES: To determine whether different interfaces affect VC measurements in ALS patients and whether the interface yielding the largest VC produces an even higher VC when re-measured after one week (learning effect). To explore the relationship between optimal interface VC and sniff nasal pressure (SNIP), a measurement of global inspiratory muscle strength. METHODS: Thirty-five patients (17 bulbar and 18 spinal ALS) were studied. Three interfaces (rigid-cylindrical, flanged, oronasal mask) were tested. One week after the first visit, VC was recorded using the optimal interface. SNIP recordings were also obtained. RESULTS: In the bulbar ALS group, median (interquartile range) VC with the flanged mouthpiece was 8.4% (3.9-15.5) larger than with the cylindrical mouthpiece (p < 0.001). VC values with oronasal mask were intermediate to VC with the other two interfaces. In spinal ALS, flanged mouthpiece VC was 4.6% (2.3-7.5) larger than with oronasal mask (p < 0.0006). The latter was 4.5% (0.6-5.2) smaller than with the cylindrical mouthpiece (p = 0.002). In both groups, VC during the second visit was greater than during the first visit (p < 0.025). SNIPs were logarithmically related to VC values recorded with the flanged mouthpiece. CONCLUSION: A flanged mouthpiece yields the largest values of VC in patients with bulbar and spinal ALS.

Comparison between rhinometric variables and nasal airing in children with mouth breathing

ABSTRACT Purpose: to analyze the correlation between the values of nasal aeration and geometry of the nasal cavities, before and after nasal cleansing in children with mouth breathing. Methods: 20 children aged 4 to 12 years old were chosen. The questionnaire Identification Index of Signs and Symptoms of Oral breathing was applied and nasal patency was assessed by nasal aeration, through the Altmann graded mirror, and the nasal geometry measured by acoustic rhinometry. After nasal cleansing and massage, the same aeration measurements and nasal geometry procedures were performed. Group normality was analyzed using the Shapiro-Wilk test considering the hypothesis of normal distribution whenever p>0.05. The Spearman's test was applied to analyze the correlation between variables (p<0.05). Results: there was a strong and significant correlation between nasal aeration and the corresponding cross-sectional area of the front of the inferior turbinate (CSA2) in the left cavity before cleansing. There were no correlations between the nasal aeration and other rhinometric variables. Conclusion: there was a correlation between nasal aeration values and the anterior portion of the turbinates, before the massage and nasal cleansing technique, in mouth breathing children. There were no significant differences when the nasal aeration was correlated with other rhinometric variables.

Giant nasal granuloma gravidarum.

Nasal granuloma gravidarum usually presents as a small vascular lesion on the septum or turbinates during pregnancy. We present a case of a giant nasal granuloma gravidarum and its management.

Intranasal glial heterotopia in a male infant: A case report.

RATIONALE: Nasal glial heterotopia is a rare type of neoplasm consisting of meningothelial and/or neuroglial elements. PATIENT CONCERNS: A 2-month-old male was evaluated for treatment of a congenital mass in the right nasal cavity near the pharynx. DIAGNOSES: The patient was preoperatively diagnosed with a congenital intranasal neoplasm. INTERVENTIONS: Nasal endoscopic resection of the nasopharyngeal mass was performed under general anesthesia. Histological examination of the resected tissue provided a diagnosis of intranasal glial heterotopia. OUTCOMES: The surgical outcome was good, with no surgical site infection. After 1 year of follow-up, the boy was asymptomatic with no recurrence. LESSONS: Excision of a nasopharyngeal mass via nasal endoscopy resulted in no recurrence during 1 year of follow-up. Before any surgical treatment for suspected glial heterotopia, the mass should be differentiated clinically and radiologically from an encephalocele to prevent the risk of cerebrospinal fluid leakage and meningitis.

Evaluation of nasal airflow resistance of operated unilateral cleft lip and palate surgery patients compared with skeletal class III individuals.

OBJECTIVE: The purpose of this study was to measure the nasal airflow resistance of operated unilateral cleft lip and palate (UCLP) patients using the anterior rhinomanometry method compared with non-cleft skeletal class III individuals with isolated maxillary hypoplasia serving as the control group. MATERIAL&METHODS: Sixteen UCLP patients who have undergone lip and palate reconstructions and alveolar cleft grafting but not advanced surgeries as the study group and 16 non-cleft skeletal class III participants as the control group (corresponded for age and sex to the study group) were included in this prospective study. All of the patients had class III occlusion due to isolated maxillary hypoplasia. Nasal airflow was measured with anterior rhinomanometry (in ml/sec) for each nostril separately. For evaluation of nasal side subgroups of the UCLP group for nasal resistance, the cleft sides and non-cleft sides of individuals were examined in two separate groups. The nasal side resistance of the control group was evaluated as the average of both nasal side resistances. The nasal resistances for nasal sides and total nasal resistance were measured in Pa/L/sec. The observed data were analyzed using Kolmogorov-Smirnov test used for normality, and the Student t-test and Mann Whitney U test used to determine the differences between the groups. P values of <0.05 were considered statistically significant. RESULTS: As the primary outcome of this study, it was found that both the cleft sides and non-cleft sides of the UCLP individuals had statistically significantly higher nasal resistance than the healthy skeletal class III control group (p < 0.05). It was revealed that the cleft side had more nasal resistance than the non-cleft side for both inspiration and expiration, but the results were not statistically significant (p = 0.41/p = 0.28). CONCLUSION: The results showed that operated UCLP patients have nasal resistance and breathing problems, even when lip, palate, and alveolar cleft operations have been performed.

Prevention of Nasal Ala Pressure Injuries With Use of Hydroactive Dressings in Patients With Nasotracheal Intubation of Orthognathic Surgery: A Randomized Controlled Trial.

PURPOSE: To compare a hydroactive dressing to an adhesive tape standard of care in the prevention of nasal ala pressure injuries associated with nasotracheal intubation during orthognathic surgery. DESIGN: Randomized controlled trial. SUBJECTS AND SETTING: The study took place in a tertiary hospital of stomatology in China. Patients undergoing general anesthesia with nasotracheal intubation during orthognathic surgical procedures were invited to participate. METHODS: Participants were divided into 2 groups: in the experimental group, a hydroactive dressing was applied to the nasal ala before the surgical procedures; the control group received standard prevention with a type of tape. Skin assessments were performed on the wards up to 72 hours after the procedures. Demographic information and potential contributing factors associated the development of nasal ala pressure injuries were collected from patients' electronic medical records. Pressure injury development was staged using National Pressure Injury Advisory staging guidelines. Pressure injury incidence was compared between groups using the χ test and odds ratio. RESULTS: The sample comprised 450 participants, 225 in each group. The incidence of nasal ala pressure injuries development was 14.222% and 4.444% in the 2 groups, respectively (P = .000). The odds ratio was 3.565 (95% confidence interval, 1.707-7.443). CONCLUSIONS: The study findings indicate that the incidence of pressure injuries of nasal ala skin protected by hydroactive dressings was lower than the standard preventive method. Hydroactive dressings should be considered as a prevention method to reduce device-related skin injuries associated with nasotracheal intubation.

Association Between Orthonasal Olfaction and Chemosensory Perception in Patients With Smell Loss.

OBJECTIVES: Self-ratings seem to be the most effortless strategy for assessment of patients' chemical senses. Notably, although flavor perception strongly relies on olfaction, the relationship between self-reported flavor perception and orthonasal olfactory tests have hitherto not been considered. The aim of this study was to investigate the relationship between self-perceived olfactory function (SO), taste (ST), and flavor perception (SF) and smell test results in patients with olfactory dysfunction (OD). METHODS: We included 203 patients with quantitative OD. Group comparison, bivariate correlation, and ordinal logistic regression were employed to quantify the relationships between predictor variables (age, gender, reason for OD, and orthonasal olfaction-summed scores of threshold, discrimination, and identification [TDI]) and outcomes of SO and SF ("impaired," "average," or "good"). RESULTS: Group comparison revealed significant differences between SO and SF (P < .001). Stronger correlations were found between SO and TDI (r = 0.64), compared to SF and TDI (r = 0.27). No relevant correlation was found between ST and TDI (r = 0.10). Higher TDI was associated with odds of higher SO in univariate (odds ratio = 1.25) and multivariable analyses (adjusted odds ratio = 1.23), and both models showed good fit of data. Conversely, regression models on the associations between TDI and changes in SF did not meet the assumption of goodness of fit. CONCLUSION: We found that higher orthonasal olfactory performance was associated with odds of higher SO in patients with OD, even after controlling for olfactory-relevant factors. To the contrary, similar models based on flavor perception failed to describe these relationships. This indicates for SF and ST to be less represented by the TDI compared to SO. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:2213-2219, 2020.

Does Nasal Cavity Enlargement Associated With Respiratory Function Improvement After Surgically Assisted Rapid Maxillary Expansion?

PURPOSE: To systematically evaluate the effects of surgically assisted rapid maxillary expansion (SARME) on nasal cavity and its associated respiratory function changes. MATERIAL AND METHODS: Multiple electronic databases were searched, authors were contacted as required, and reference lists of potentially relevant studies were screened. Articles that included patients older than 16 who had received SARME were considered. Data extraction and quality assessment were performed independently and in duplicate. RESULTS: Eight articles, including 161 patients, were finally selected and analyzed. Nasal cavity significantly augmentation after SARME has been recognized by 7 studies with moderate-quality evidence. Among them, the nasal cavity volume increased <20% in 4 studies, 20% to 40% in 1 study, and >40% in 2 studies. Totally, the range of increasing in nasal cavity volume was 7.6% to 99%. One study had recorded the nasal expiratory and inspiratory flow significantly increased 18.5% and 21.7%, respectively. CONCLUSION: SARME was found to produce meaningful volume augmentation in nasal cavity with adult patients. However, the improvement of nasal respiratory function has not been well elucidated; thus, SARME is not yet recommended for the purpose of improving nasal respiratory.

An optimization method for surgical reduction of hypertrophied inferior turbinate.

Surgical reductions of the hypertrophied inferior turbinate (HIT) can improve nasal obstruction. However, there is currently a lack of personalized and objective methods to guide surgical operations, which results in the excessive or inadequate resection of HIT. In this study, we proposed an optimizing method based on homotopy deformation to determine the resected amount and shape of the tissue by matching the flow resistance in the two nasal passageways. The simulation results obtained using computational fluid dynamics showed that after such an optimization procedure, the most obstructed nasal side could have a similar air flux as the less obstructed side. A 35% and a 56% less tissue resection in the optimizing operation compared to that in the total turbinectomy could well balance the air flow between the two nasal cavities in the simulations for patients 1 and 2 with unilateral nasal obstruction respectively. Compared with the optimization operation, the total turbinectomy made a more aggressive resection of HIT, which could worsen the air conditioning capacity of the nose. A sensitivity test indicated that in the optimization operation, the most constricted region in the nasal cavity should be adequately enlarged. However, more tissue resection than is required for the optimization operation did not improve the flow in the obstructed side strikingly. Simulations of the optimization operation in both nasal cavities for a patient with bilateral nasal obstruction were also performed. The flow rate could reach the normal level and be well balanced in the two sides after such an optimization procedure.

Impact of posterior septum resection on nasal airflow pattern and warming function.

Background: The functional significance of the posterior segment of the septum is not fully understood.Aims/Objectives: The purpose of this study was to evaluate the impact of posterior septum resection with varying extents on nasal airflow pattern and warming function, and to determine the appropriate resection extent on posterior septum without disturbing airflow pattern.Material and Methods: Three dimensional models were established from the nasal CT scan of a healthy female volunteer without nasal disease. The models included the normal, as well as 1 cm, 2 cm, and 3 cm extent of posterior septum resection by virtual surgery. Using computational fluid dynamics, the airflow characteristics such as average and peak airflow velocity, average wall shear stress, average temperature and turbulence kinetic energy were recorded and compared among the four models.Results: By comparison with the normal model, the virtual surgeries with varying extents of posterior septum resection (1 cm, 2 cm, and 3 cm), demonstrated little alteration on indices of the average and peak airflow velocity, average wall shear stress, airflow temperature and turbulence kinetic energy. However, a statistical difference of the abovementioned indices existed when compared between varying planes of the nasal cavity (p < .001), although this did not appear to be significantly influenced by the degree of posterior septectomy.Conclusions and significance: From an aerodynamics perspective, little disturbance on airflow pattern and warming function of nasal cavity could be detected with increasing resection of posterior septum (up to 3 cm). These results may imply that resection of the posterior septum (up to 3 cm) has little impact on nasal function.

Breeding French bulldogs so that they breathe well-A long way to go.

Brachycephalic syndrome (BS) is a pathophysiological disorder caused by excessive soft tissue within the upper airways of short-nosed dog breeds, causing obstruction of the nasal, pharyngeal and laryngeal lumen, resulting in severe respiratory distress. As the prevalence of BS appears to be high among some of the affected breeds, there is an urgent need for breeding efforts to improve the health status of those dogs. In the present study, we evaluated correlations between morphometric and other phenotypic characteristics and BS in a population of 69 French bulldogs from Denmark to identify parameters that could serve as a basis for breeding against BS. Furthermore, the genetic variation was monitored to determine whether it would be possible to breed based on these characteristics without simultaneously causing a critical reduction in genetic variation. Six phenotypic characteristics were correlated with the Brachycephalic Syndrome Functional (BSF) score. Among the morphometric risk factors, nostril stenosis (NS) and neck girth (NG) had the highest impact on the BSF score, accounting for 32% and 4% of the variation, respectively. The genetic variation in the population was comparable to other pure breeds, i.e. estimated and observed heterozygosity was 0.60 and the average inbreeding coefficient was 0.01. If only dogs with Grades 1 and 2 NS (no or only mild NS) were selected for breeding the mean BSF score would be reduced significantly. However, it would result in the exclusion of 81% of the population for breeding and this is not prudent. Excluding only dogs with severe stenosis (Grade 4) would exclude 50% of the population without any adverse impact on genetic variation within the population. Although exclusion of dogs with Grade 4 would result in an apparent reduction in the mean BSF score, this reduction is not significant. As NS accounts for 32% of the variation in BSF score, a possible long term strategy to reduce the prevalence of the BS in French bulldogs would seem to be a selection scheme that first excluded dogs with the most severe NS from breeding, gradually moving towards selecting dogs with lower NS grades. According to our findings there is no viable short term solution for reducing the prevalence of BS in the French bulldog population.

[Biophysical mechanisms of dehydration of nasal cavity secretion in inflammatory diseases of the upper respiratory tract]. / Biofizicheskie mekhanizmy degidratatsii sekreta polosti nosa pri vospalitel'nykh zabolevaniiakh verkhnikh dykhatel'nykh putei.

The purpose of the study is an experimental-theoretical study of the mechanisms of structuring the secretion of the nasal cavity, in the process of its dehydration in inflammatory diseases of the upper respiratory tract. The work shows the general patterns of dehydration of natural biological fluids and their model solutions. Simulation of dehydration of the secret allowed us to identify the most informative parameters of changes in its composition in pathology and to develop criteria for diagnosing the inflammatory process of the VDP using the wedge-shaped dehydration method. The study clarified the mechanisms of dehydration of biological fluid, which expanded the possibilities of diagnosing diseases of the VDP.