Pulmonary function studies in patients with upper airway obstruction

The Effect of Marked Nasal Septal Deviation on Left Ventricular Function and Blood Markers

OBJECTIVES

This study aimed to assess the effect of nasal septoplasty in patients with marked nasal septal deviation (MNSD) on subjective perception of nasal patency, echocardiography, and hematologic parameters.

METHODS

Seventy-nine consecutive patients (mean age, 29.9 ± 9.7 years; 57 men and 22 women) at least 18 years old were diagnosed as MNSD consistent with presenting symptom of chronic nasal obstruction lasting at least 3 months. Complete blood count measurement to assess mean platelet volume (MPV) and neutrophil to lymphocyte ratio (NLR), the Nasal Obstruction Symptom Evaluation (NOSE) questionnaire, and echocardiography were performed for all patients just before and at postoperative third month of septoplasty.

RESULTS

The MPV (0.021), NLR (<0.001), and NOSE (<0.001) were all significantly decreased, and global longitudinal strain (GLS) value (<0.001) were also significantly increased at postoperative third month. Correlation analysis also indicated that ΔNLR was positively correlated with ΔGLS (r = 0.385, P < 0.001), and ΔNOSE (r = 0.436, P < 0.001), and correlated negatively with the ΔMPV (r = -0.302, P = 0.024). ΔGLS was also positively correlated with the ΔNOSE (r = 0.769, P < 0.001).

CONCLUSION

Septoplasty for MNSD could provide not only alleviation of otorhinolaryngologic symptoms but also improvement in subclinical left ventricular systolic dysfunction and decline in MPV and NLR levels.

Flow-Volume Curve Analysis for Predicting Recurrence After Endoscopic Dilation of Airway Stenosis

BACKGROUND

The flow-volume curve is a simple test for diagnosing upper airway obstruction. We evaluated its use to predict recurrence in patients undergoing endoscopic dilation for treatment of benign upper airway stenosis.

METHODS

The data of 89 consecutive patients undergoing endoscopic dilation of simple upper airway stenosis were retrospectively reviewed. Morphologic distortion of flow-volume loop (visual analysis) and quantitative criteria, including maximal expiratory flow rate at 50% of the vital capacity (MEF_50%)/maximal inspiratory flow rate at 50% of the vital capacity (MIF_50%) of less than 0.3 or more than 1.0, forced expiratory volume in 1 second/MEF exceeding 10, and forced expiratory volume in 1 second/forced expiratory volume in .05 second exceeding 1.5, were considered predictive of recurrence. In all cases, the recurrence was confirmed by radiologic or bronchoscopic findings, or both. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of visual, quantitative, and aggregate criteria for detecting recurrence were computed and compared.

RESULTS

Of 89 patients treated, 27 (30%) had a recurrence. Visual analysis presented a sensitivity, specificity, PPV, NPV, and accuracy of 63%, 83.9%, 63%, 83.9%, and 77.5%, respectively. Among the quantitative criterion, the MEF_50%/MIF_50% was the most accurate, having a sensitivity, specificity, PPV, NPV, and accuracy of 77.8%, 79%, 61.8%, and 89.1%, and 78.7%, respectively. Aggregate criterion presented the best yield compared with other criteria in sensitivity (81.5%), specificity (91.9%), PPV (81.5%), NPV (91.9%), and accuracy (88.8%).

CONCLUSIONS

The flow-volume curve is a simple and noninvasive method to monitor patients undergoing endoscopic dilation of upper airway stenosis. Morphologic changes in the flow-volume loop and in the MEF_50%/MIF_50% ratio are suggestive of recurrence and guide the physician to implement the follow-up with further diagnostic (non)invasive examinations.

Simulation using novel equipment designed to explain spirometric abnormalities in respiratory disease enhances learning in higher cognitive domains

Simulation of disorders of respiratory mechanics shown by spirometry provides insight into the pathophysiology of disease but some clinically important disorders have not been simulated and none have been formally evaluated for education. We have designed simple mechanical devices which, along with existing simulators, enable all the main dysfunctions which have diagnostic value in spirometry to be simulated and clearly explained with visual and haptic feedback. We modelled the airways as Starling resistors by a clearly visible mechanical action to simulate intra- and extra-thoracic obstruction. A narrow tube was used to simulate fixed large airway obstruction and inelastic bands to simulate restriction. We hypothesized that using simulators whose action explains disease promotes learning especially in higher domain educational objectives. The main features of obstruction and restriction were correctly simulated. Simulation of variable extra-thoracic obstruction caused blunting and plateauing of inspiratory flow, and simulation of intra-thoracic obstruction caused limitation of expiratory flow with marked dynamic compression. Multiple choice tests were created with questions allocated to lower (remember and understand) or higher cognitive domains (apply, analyse and evaluate). In a cross-over design, overall mean scores increased after 1½ h simulation spirometry (43-68 %, effect size 1.06, P < 0.0001). In higher cognitive domains the mean score was lower before and increased further than lower domains (Δ 30 vs 20 %, higher vs lower effect size 0.22, P < 0.05). In conclusion, the devices successfully simulate various patterns of obstruction and restriction. Using these devices medical students achieved marked enhancement of learning especially in higher cognitive domains.

Utility of Peak Inspiratory Flow in Managing Subglottic Stenosis

Objectives:

To identify the utility of peak inspiratory flow (PIF) in the assessment and management of subglottic stenosis through correlation of clinical presentation with PIF.

Study Design:

Case report.

Methods:

Review of the clinical course of a 31-year-old woman with the diagnosis of granulomatosis with polyangiitis. Repeated PIF measurements at clinic visits were obtained over a 30-month follow-up.

Results:

Twenty-seven PIF measurements were obtained at 31 otolaryngology clinic visits. Correlations were identified between low PIF measurements with the clinical symptom shortness of breath (2.04 ± 0.38 L/s, n = 10), clinically recorded stridor at rest (1.64 ± 0.41 L/s, n = 3), and urgent operative intervention (1.60 ± 0.23 L/s, n = 5). Correlations were identified between high PIF measurement with patient report of normal breathing (3.07 ± 0.35 L/s, n = 16) and clinical observation of absence of stridor at rest (2.81 ± 0.32 L/s, n = 23). There was a statistically significant difference in the patient’s PIF values with patient-documented shortness of breath vs no shortness of breath ( P = .001) and clinician-noted stridor vs no stridor ( P = .017).

Conclusion:

Peak inspiratory flow measurements correlate with degree of airway compromise and are helpful to monitor the degree of airway obstruction and document response to treatment.

Pulmonary function tests in children with adenotonsillar hypertrophy

OBJECTIVE

Adenotonsillar hypertrophy, a common malady in children may lead on to cardiopulmonary dysfunction in untreated cases. The present study was designed to see alteration in pulmonary function tests i.e. spirometric parameters and blood oxygen saturation consequent to adenotonsillar hypertrophy and subsequent changes after adenotonsillectomy.

METHODS

Spirometry and pulse oximetry were carried out in 40 children with adenotonsillar hypertrophy of both sexes between the age of 7 and 14 years and 40 age and sex matched healthy children. The test was repeated one and half months after surgery in study group and data was statistically analyzed using students' t-test.

RESULTS

The flow volume plot was abnormal in all the patients along with hypoxia, reduced FIF50% and, increased FEF50%/FIF50%, FEV1/PEFR, FEV1/FEV0.5 ratios. There was statistically significant improvement in above parameters following surgery.

CONCLUSIONS

Spirometry can prove an useful diagnostic tool in adenotonsillar hypertrophy for deciding early intervention to prevent cardio pulmonary complications.

Occupational upper airway disease

The upper airway plays a critical role in filtering and conditioning air for the lungs. It provides the first line of warning and defense against microbials, allergens, and toxic inhalants. Current evidence suggests that the upper airway is susceptible to many of the pathogenic processes that the agents cause in the lower respiratory tract. Work-related rhinosinusitis or vocal cord dysfunction should prompt physicians and employers to identify the injurious agent(s) and formulate strategies to eliminate or reduce such exposures. Improving the work environment will prevent the development of new cases and the worsening of symptoms in existing cases.

Variable extrathoracic airflow obstruction and chronic laryngotracheitis in Gulf War veterans

STUDY OBJECTIVES

To study the flow-volume loop for evidence of variable extrathoracic airflow obstruction in Persian Gulf War veterans.

DESIGN

Retrospective case-control, single-center study.

SETTING

The pulmonary division of an academic health-care center.

SUBJECTS

A convenience sample of the Persian Gulf Registry.

MEASUREMENTS AND INTERVENTIONS

(1) Midvital capacity ratio (ratio of maximum forced midexpiratory to maximum forced midinspiratory flow). This ratio is the criterion standard for the diagnosis of variable extrathoracic airflow obstruction. (2) Evaluation of the anatomy and function of the extrathoracic airway by fiberoptic bronchoscopy. (3) Further investigation into the airway abnormality by histologic evaluation of tracheal biopsy samples in Gulf War veterans only.

RESULTS

Midvital capacity was > 1.0 in 32 of 37 Gulf War veterans compared with only 11 of 38 control subjects. The mean (+/-SD) value was 1.37+/-0.4 among Gulf War veterans and 0.88+/-0.3 among control subjects (p=0.0000005). FVC and its ratio to FEV1 were normal in all these subjects. Bronchoscopy showed inflamed larynx and trachea in all (n=17) Gulf War veterans. Histologic study showed chronic inflammation of the trachea in everyone (n=12) who had an adequate biopsy sample.

CONCLUSION

Physicians should be made aware of the presence of chronic inflammation of the upper airways and inspiratory airflow limitation in a number of Gulf War veterans.

Extrathoracic airway dysfunction in cough associated with gastroesophageal reflux

BACKGROUND

Cough associated with gastroesophageal reflux (GER) may originate in extrathoracic airway receptors made hypersensitive by acid-induced mucosal injury.

OBJECTIVE

We investigated the role of laryngeal disease and dysfunction in the pathogenesis of GER-associated cough in nonasthmatic patients.

METHODS

Seven patients with GER-associated cough were compared with 7 patients with GER but no cough. The patients underwent fiberoptic endoscopy for assessment of laryngitis and esophagitis (expressed by scores); esophageal manometry; 24-hour pH monitoring; lung function tests; and histamine inhalation challenge with assessment of bronchial threshold (concentration provoking 10% fall in FEV1 [PC10]), extrathoracic airway threshold (concentration provoking 25% fall in the maximal midinspiratory flow [PC25MIF50]), and cough threshold (concentration provoking 5 or more coughs PCcough). The patients were reevaluated after 3 months of medical treatment for GER.

RESULTS

Patients with cough, compared with those without cough, had significantly higher laryngitis scores (P = .002), lower esophageal sphincter pressures, longer time with pH below 4 (P = .003), greater number of episodes of reflux longer than 5 minutes (P = .016), longer esophageal clearance time (P = .048), and significantly lower PC25MIF50 (P = .005) and PCcough (P = .008) values. Laryngitis score was significantly inversely related to either PCcough (P < .001) or PC25MIF50 (P <.01) but not to PC10. Laryngitis score, PC25MIF50, and PCcough were all closely related to GER severity. After GER treatment, laryngitis, PC25MIF50, and PCcough were all significantly improved.

CONCLUSIONS

These findings suggest that GER-associated cough is strongly associated with laryngeal disease and dysfunction consequent to acid reflux injury in nonasthmatic patients.

Are asthma-like symptoms due to bronchial or extrathoracic airway dysfunction?

Patients with asthma-like symptoms may not have asthma but obstruction of the extrathoracic airway (EA). To evaluate if dysfunction of the EA causes asthma-like symptoms, we assessed bronchial and EA responsiveness to inhaled histamine in 441 patients who presented with at least one of three key symptoms--cough, wheeze, dyspnoea--but had neither documented asthma nor bronchial obstruction. The histamine concentrations causing a 20% fall in forced expiratory volume in 1 s (PC20FEV1) and a 25% fall in maximal mid-inspiratory flow (PC25MIF50) were used as respective thresholds of bronchial and EA responsiveness. Values 8 mg/mL or less indicated bronchial (B-HR) or EA hyper-responsiveness (EA-HR). The influence of concurrent upper respiratory tract diseases, such as post-nasal drip (PND), pharyngitis, laryngitis and sinusitis, was also assessed. We found four response patterns to the histamine challenge: EA-HR in 26.5% of the patients, B-HR in 11.1%, combined EA-HR and B-HR in 40.6%, and no-HR in 21.8%. Cough was reported by 79% of the patients, wheeze by 53%, and dyspnoea by 40%. Patients with cough as the sole presenting symptom (34.2%), as compared with those with wheeze and/or dyspnoea (20%), had significantly greater probability of having EA-HR (OR 5.35, 95% CI 3.25-8.82) and lower probability of having B-HR (OR 0.45, CI 0.28-0.70); patients with cough plus wheeze and/or dyspnoea (45.8%) had significantly greater probability of having both EA-HR and B-HR than either those with cough alone (OR 2.48, CI 1.49-4.13), or those with wheeze and/or dyspnoea but not cough (OR 1.74, CI 1.36-2.22). EA-HR alone or combined with B-HR was strongly associated with EA diseases, particularly pharyngitis and PND. Cough was significantly associated with PND, either when it was the sole symptom (OR 2.16, CI 1.14-4.09) or when it was combined with wheeze and/or dyspnoea (OR 3.53, CI 1.97-6.33). Our results suggest that extrathoracic airway dysfunction may account for asthma-like symptoms, particularly chronic cough. This abnormality seems to be sustained by chronic diseases of the upper respiratory tract.

Dyspnea in dystonia. A functional evaluation

BACKGROUND

Dystonia consists of action-triggered sustained focal muscle contractions, worsened by effort, and resulting in voice changes, abnormal posturing, and dyspnea. The cause of dyspnea, previously unexplained, is the basis of this report.

METHODS

Since the maximal efforts required to perform pulmonary function testing (PFT) could worsen the muscular contractions in dystonic patients, we used several tests to identify possible causes of dyspnea. These included spirometry with flow volume loops (FVL), tidal volume breathing, maximum voluntary ventilation (MVV), and inspiratory and expiratory muscle pressures (PImax, PEmax), sitting and supine. We used cycle ergometry with arterial blood gas (ABG) values to detect cardiac/pulmonary limitations and respiratory inductive plethysmography (RIP) to assess chest wall/abdominal movements for synchrony. Dynamic videofluoroscopy (VF) assessed and recorded the action-triggered muscle activity of the upper airways and the diaphragm during quiet breathing, speech, swallowing, and maximal respiratory maneuvers similar to the efforts required during PFT.

RESULTS

Twenty-six dystonic patients, 12 women and 14 men, ages 14 to 70 years (mean age, 52.3 years) were evaluated. Their neurologic classification included 22 primary (idiopathic) and 4 secondary (2 postneuroleptic use, 2 posstraumatic). Four patients originally classified as having focal dystonia had dyspnea and were found to have diaphragmatic and/or upper airway dysfunction too. The PFTs showed abnormal FVL and/or tidal volume breathing patterns, with intermittent interruptions of air flow during inspiration or expiration in 20 of 24 patients. The VF was abnormal in 24 of 26 patients: 19 patients had combined upper airway (UA) and diaphragmatic dysfunction (DD); 1 patient had UA dysfunction alone, and 4 patients had DD alone. Except for poor effort and/or dystonic movements, cycle ergometry was normal in 18 of 21 patients. The ABG values and/or pulse oximetry were normal in 19 of 22 patients.

CONCLUSION

Dyspnea in dystonia appears to be due to excessive and/or dysynchronized contractions of the upper airways and/or diaphragm, with usually normal gas exchange. These spasmodic and irregular muscular contractions during speech and daily activities are associated with the sensation of excessive effort to overcome the spasms. Excessive spasms can be triggered during PFT and are best detected on FVL patterns coupled with dynamic VF.

Extrathoracic and intrathoracic airway responsiveness in sinusitis

BACKGROUND

Asthma associated with sinusitis is supposed to be sustained by bronchoconstrictive reflexes originating in extrathoracic airway (EA) receptors.

OBJECTIVE

The study was designed to evaluate the relationship between EA responsiveness and bronchial responsiveness in sinusitis.

METHODS

We performed histamine inhalation challenge in 106 patients with chronic sinusitis, during disease exacerbation and after treatment with antimicrobials and nasal flunisolide (100 micrograms daily) for 2 weeks. Forced expiratory volume in 1 second (FEV1) and maximal mid-inspiratory flow (MIF50) were the respective indexes of bronchial and EA narrowing; the histamine concentrations causing a 20% fall in FEV1 (PC20) and 25% drop in MIF50 (PC25MIF50) were used as thresholds of bronchial and EA responsiveness. Thresholds of 8 mg/ml or less were assumed to indicate bronchial hyperresponsiveness (B-HR) or EA hyperresponsiveness (EA-HR).

RESULTS

During sinusitis exacerbation 76 patients had EA-HR, which in 46 was associated with B-HR. The values of PC20 were closely related with those of PC25MIF50 (p < 0.001). EA-HR and B-HR were strongly associated with pharyngitis. After treatment, mean PC25MIF50 and PC20 were significantly increased (p < 0.001). The improvement of PC25MIF50 was closely related to that of PC20 (p < 0.001) and to the decrease in neutrophils in nasal lavage (p < 0.05). EA-HR reversed in 58 patients and improved in 10; B-HR reversed in 29 and improved in 12.

CONCLUSIONS

Our findings suggest that in sinusitis, B-HR may be sustained by constrictive reflexes originating in pharyngeal receptors, made hypersensitive by seeding of the inflammatory process.

Evaluation of upper airway obstruction after partial laryngectomies by radiological method and flow-volume loop analysis

Anatomical and functional estimations of the upper airways in patients after partial laryngectomies (cordectomy, hemilaryngectomy, enlarged hemilaryngectomy) carried out due to cancer are discussed in this paper. The post-operative lumen of the larynx and the trachea were estimated by radiological examination. The coefficient larynx/trachea (L/T) was proposed to describe fixed obstruction. At the same time, all patients underwent spirometric examinations. Inspiratory and expiratory parameters of the flow-volume loop were evaluated. In 39 patients the L/T coefficient was lower than in a group of patients with chronic bronchitis (p < 0.05). Also inspiratory and some expiratory parameters of the flow-volume loop decreased in contrast to the group with chronic bronchitis. All results showed the usefulness of radiological and spirometric methods in detecting upper airway obstructions and confirmed their fixed character. The influence of the area of operation on the degree of upper airway obstruction was emphasized.

Airway complications in relapsing polychondritis

To analyze the importance of airway involvement in relapsing polychondritis, an illustrative case report is presented and 62 patients reported in the literature with serious airway complications are reviewed. There were 47 female and 17 male patients, with an average age of 40.3 years (range, 2 to 73 years). Patients were seen with hoarseness, breathlessness, cough, stridor, wheezes, and tenderness over laryngotracheal cartilages. Respiratory tract involvement was confirmed by conventional radiography, tomography, computed tomography, dynamic pulmonary function tests, and bronchoscopy. Corticosteroids and antiinflammatory and immunosuppressive agents were used in these patients. Tracheostomy was performed in 18 patients. Death occurred in 13 patients despite tracheostomy or corticosteroid therapy, or both. A detailed analysis of the clinical, radiological, and pulmonary function studies is presented, with emphasis on upper airway mechanics. The medical and surgical management options are reviewed, including the use of endotracheal prosthesis and extraluminal splinting in dynamic airway collapse.

Histamine hyperresponsiveness of the extrathoracic airway in patients with asthmatic symptoms

Functional abnormalities of the extrathoracic airway (EA) may produce symptoms mimicking bronchial asthma. We assessed the bronchial (B) and EA responsiveness to inhaled histamine in 40 patients with asthmatic symptoms and in nine asymptomatic controls. FEV1 and maximal mid-inspiratory flow (MIF50) were used as index of bronchial and EA narrowing. Hyperresponsiveness of the intra-(BHR) or extra-(EA-HR) thoracic airway was diagnosed when the provocative concentrations of histamine (PC20FEV1 or PC25MIF50) were less than 8 mg/ml. Fiberoptic laryngoscopy was performed in nine patients and three controls. The glottal region was measured at mid-volume of maximal inspiration (AgMI) and expiration (AgME) before and after histamine. Predominant EA-HR was found in 13 patients, predominant BHR in 12, equivalent BHR and EA-HR in another 12; no significant airway narrowing was observed in three patients and in the nine controls. EA-HR was significantly associated with female sex, sinusitis, post-nasal drip, dysphonia; BHR with atopy, wheezing and lower MEF50. The percent change in AgMI after histamine was closely related to the PC25MIF50 (r = 0.87, P less than 0.001), that of AgME to the PC20FEV1 (r = 0.78, P less than 0.01). These findings suggest that the assessment of EA responsiveness may be useful in the evaluation of asthmatic symptoms, especially in patients with no BHR.

Hyperresponsiveness of the extrathoracic airway in patients with captopril-induced cough

It has been suggested that cough from captopril may originate from an increased sensitivity of receptors in the extrathoracic airway (EA). To explore this hypothesis, we assessed the responsiveness of EA and bronchi and the cough sensitivity to inhaled histamine in nine hypertensive patients with captopril-induced cough (group 1) during treatment and one month after withdrawal of the drug treatment. Nine patients who were asymptomatic while receiving captopril (group 2) and nine patients receiving no current treatment (group 3) served as controls. The EA responsiveness was assessed by using the maximal midinspiratory flow (MIF50) as an arbitrary index of EA constriction and was expressed as the histamine concentration causing a 25 percent decrease in MIF50 (PC25MIF50). PC15FEV1 was the index of bronchial responsiveness and PCcough (dose causing five or more coughs) was that of cough sensitivity. Airway hyperresponsiveness (EA-HR or BHR) was diagnosed when PC25MIF50 or PC15FEV1 were 8 mg/ml or lower. Patients with captopril-cough, as compared with controls, had significantly lower values of PC25MIF50, PC15FEV1, and PCcough; EA-HR and BHR were found, respectively, in seven and three of these patients and in none of the control subjects. In all the patients of group 1, cough and EA-HR resolved after withdrawal of captopril treatment, while BHR persisted in one. PC25MIF50, PC15FEV1, and PCcough were all significantly improved. Our findings suggest that cough during captopril therapy may originate from receptors in the EA.

The biphasic spirogram: a clue to unilateral narrowing of a mainstem bronchus

Two patients with narrowing of a mainstem bronchus each showed two unusual functional features that are likely to be characteristic of this condition. The maximum inspiratory flow-volume curve showed an end inspiratory "tail" and the forced expiratory spirogram had a biphasic shape with normal initial curvature but a "straight line" appearance in later expiration. In one patient relief of the bronchial stenosis by the insertion of a stent restored normal contours to the spirogram and flow-volume curves.

Comparison of dynamic lung function indices during forced and quiet breathing in upper airway obstruction, asthma, and emphysema

We compared the dynamic lung function indices in patients with asthma (n = 27), emphysema (n = 20), and UAO (n = 18), with the purpose being to examine whether different patterns of abnormalities could be found and which tests were most discriminative among the three groups. Forced expiratory indices were measured (FEV1; PEF; MEF50%), as well as indices obtained during quiet breathing (Raw; Gaw; Gaw/VL). The three groups were comparable as far as PEF was concerned (about 60 +/- 20 percent of predicted, yet the group with UAO showed significantly larger FEV1 (84 percent of predicted vs 55 percent and 57 percent of predicted in asthma and emphysema respectively), and larger MEF50% (71 percent of predicted vs 25 percent and 23 percent of predicted in the other groups), and the group with asthma had the largest Raw (0.37 +/- 0.18 kPa.s.L-1 vs 0.24 +/- 0.13 in UAO and 0.22 +/- 0.10 in emphysema). From these functional tests, several ratios were derived which were discriminative among the three groups. Upper airway obstruction could be recognized by a significantly lower PEF/MEF50% ratio and higher FEV1/PEF ratio than in the other conditions. Furthermore, a distinction between asthma and emphysema could be made by comparing airway patency during forced and quiet breathing, ie, the MEF50%/Gaw ratio. This ratio was, in fact, significantly different for all three groups, having the lowest value in emphysema (0.19 +/- 0.08 kPa vs 0.44 +/- 0.23 kPa and 0.63 +/- 0.34 kPa in asthma and UAO, respectively). Within the group with UAO, those with variable intrathoracic obstruction showed the least difference from asthma and emphysema for the measured indices.

Laryngeal obstruction assessed by computed tomography

The aim of this study was to find out if laryngeal obstruction could be assessed by measuring the glottic area using computed tomography (CT). Results from model studies were compared with those from twelve patients with laryngeal diseases. Determination of the orolaryngeal airway resistance (Rol) was used as a reference method. The correlation between airway resistance and area in both the model and among the patients was consistent, with a curvilinear relationship. The results indicate that it is possible to measure the area of a short obstruction by CT and that this area determines the degree of obstruction.

Functional assessment after laryngotracheoplasty

Laryngotracheal stenosis is a difficult problem to manage. Functional assessment is measured primarily on the ability to successfully decannulate the patient. In an effort to identify reliable, objective parameters for postoperative functional assessment, we present a retrospective study of 10 postlaryngotracheoplasty patients. All subjects underwent analysis with computerized tomography, translaryngeal manometry, acoustic reflection, flow volume loops (FVL), and voice analysis. Our results led us to conclude that accurate functional assessment is best provided by use of a combination of CT and spectral voice analysis.

Total respiratory resistance and reactance in patients with upper airway obstruction

In 18 patients with upper airway obstruction, we measured dynamic lung volumes, maximal flows, airway resistance (Raw), and total respiratory resistance (Rrs) and reactance (Xrs) at various frequencies by means of a forced oscillation method. Patients were classified according to the site and the type of the obstruction. The values of Raw, Rrs and Xrs were tightly correlated and reflected the overall importance of the obstruction. In comparison with patients with chronic obstructive pulmonary disease the values of Rrs tend to be higher and to be influenced more by support of the cheeks during the measurement. These differences are not diagnostic, however.

Spectrum of advanced upper airway obstruction due to goiters

Five patients with advanced upper airway obstruction due to goiter were identified in our institution. All had symptoms of respiratory insufficiency to such a degree that surgery was clearly indicated. Functional characteristics of this group were compared with prior series of goiter patients who had less severe respiratory symptoms. A peak inspiratory flow less than 1.5 L/sec characterized this group who required surgery.

Respiratory function in post-laryngectomy patients related to stomal size

Thirty-nine laryngectomized patients from the Professorial Unit of The Royal National Throat, Nose and Ear Hospital, London, were recalled between 6 months and 18 years after operation. The tracheal and stomal diameters were measured and, in addition to a full general examination, respiratory function tests (including arterial blood gas estimations) were performed. Most patients had impaired respiratory function tests which were in excess of the expected impairment due to age alone. The study suggests that impaired function is due to intercurrent pulmonary and cardiovascular diseases, rather than anatomical factors related to the changed upper airway. There was no correlation between stomal size or tracheal/stomal cross sectional area ratio and the measured respiratory function.

Chronic Upper Airway Obstruction: Value of the Flow Volume Loop Examination in Assessment and Management

Chronic obstructive lesions of the upper airways such as post-traumatic strictures, bilateral vocal cord paralysis and chronic inflammatory foci are uncommon. The functional assessment of the severity and character of an obstruction is important both for diagnosis and management, and may also allow evaluation of the efficacy of medical and surgical treatment. There are limitations of simple spirometric pulmonary function tests, which are evident when assessing upper airways obstruction. The flow volume loop is a graphic recording of airflow during maximal respiration and expiration at different lung volumes, and may be affected in a characteristic way by alterations in the airway resistance. Three unusual cases of chronic upper airway obstruction are presented which illustrate the value of the flow volume loop examination in their management.

Rehabilitation of the crippled larynx: application of the Tucker technique for muscle-nerve reinnervation

Interruption of laryngeal innervation may partially or totally impair respiration, deglutition and phonation--the three basic laryngeal functions. Tucker has developed a principle of muscle-nerve pedicle transfer for laryngeal reinnervation to relieve airway obstruction following bilateral recurrent laryngeal nerve injury. We have applied the principle of reinnervation proposed by Tucker to treat patients not only with airway obstruction, but also with aspiration and impaired phonation due to interruption of laryngeal innervation. There were 23 patients in this study. The functional defects included: voice alteration in 10 patients, airway obstruction in 8 and aspiration, as well as a voice change, in 5. The causes of injury were surgery in 9 patients, trauma in 5, tumor in 3, polio in 1 and a birth defect in 1 patient. No cause of nerve injury could be determined in 4 patients. The technique employed involved selective reinnervation of the laryngeal nerve branches to one or more laryngeal muscle groups; the muscle groups reinnervated were selected so as to overcome the functional defect of each particular patient. The patients have been followed for 6 mo. or longer. The results have been independently evaluated by a speech pathologist and documented by indirect and direct endoscopic observations, as well as by audio and audio-video recordings. In some cases, there was further documentation by cine-fluoro-audio tape recordings, laryngo-pharyngography, laryngeal tomography and pulmonary function studies. The muscle-pedicle transfer technique described by Tucker was found to be useful to correct laryngeal dysfunction in carefully selected cases.

Upper airways obstruction with bilateral vocal cord paralysis

In ten patients with bilateral vocal cord paralysis, we demonstrated variable extrathoracic airway obstruction. The ratio of forced expiratory flow at 50 percent vital capacity to forced inspiratory flow at the same lung volume (VE50/VI50) was 1.65 +/- 0.77 (mean +/- 1 SD). There was marked variability of inspiratory flow obstruction with a mean VI50 of 1.63 +/- 0.75 liters/ sec and a range from 0.9 liters/sec to 3.2 liters/sec. Nine of the ten patients required tracheostomy for symptoms of dyspnea. Follow-up flow volume loops were obtained to document the effects of surgical intervention and tracheostomy.

Airflow in unilateral vocal cord paralysis before and after Teflon injection

The effect of unilateral vocal cord paralysis and intracordal Teflon injection on maximum expiratory and inspiratory flows was studied in 15 consecutive patients. Ten patients had a ratio of forced expiratory flow to forced inspiratory flow at 50% vital capacity (Ve50/Vi50) more than one. Of the remaining five, four had low Ve50 consistent with underlying bronchial disease. Repeat studies were obtained in 10 patients two or more weeks after Teflon injection into a vocal cord for voice therapy. Maximum expiratory flow rates did not change (means 6.64 +/- 0.881/sec before and 6.47 +/- 1.101/s after injection). Inspiratory flow at 50% vital capacity improved in all six patients with a forced expiratory volume in one second (FEV1) greater than 75% of the forced vital capacity (FVC). In patients with an FEV1 less than 75% FVC, no consistent changes could be seen. We conclude that a high Ve50/Vi50 suggestive of variable extrathoracic airways obstruction is a frequent finding in the presence of unilateral vocal cord paralysis. Teflon injection does not cause a significant reduction in forced expiratory flows and improves inspiratory flows in subjects without evidence of underlying bronchial disease.

Upper airway obstruction

A large number of diseases may present with respiratory distress. In adults, upper airway obstruction (UAO) is relatively rare. Consequently, UAO may initially be overlooked in the differential diagnosis of the dyspneic patient. Because it may progress rapidly, delays or errors in diagnosis can be critical. During an eight-month period in one emergency department, seven adult patients with potentially life-threatening diseases of the upper airway were seen. To reacquaint physicians with the syndrome of mechanical obstruction of large airways, several illustrative cases are presented and the syndrome is discussed.

Diagnosis of upper airway obstruction by pulmonary function testing

We compared 11 patients with upper airway obstruction (obstruction at or proximal to the carina) to 22 patients with chronic obstructive pulmonary disease and to 15 normal subjects utilizing spirometry, lung volumes, airway resistance, maximal voluntary ventilation, single-breath diffusion capacity, and maximal inspiratory and expiratory flow-volume loops. Four values usually distinguished patients with upper airway obstruction: (1) forced inspiratory flow at 50 percent of the vital capacity (FIF50%) less than or equal to 100 L/min; (2) ratio of forced expiratory flow at 50 percent of the vital capacity of the FIR50% (FEF50%/FIF50%) larger than or equal to 1; (3) ratio of the forced expiratory volume in one second measured in milliliters to the peak expiratory flow rate in liters per minute (FEV1/PEFR) larger than or equal to 10 ml/L/min; and (4) ratio of the forced expired volume in one second to the forced expired volume in 0.5 second (FEV1/FEV0.5) larger than or equal to 1.5. The last ratio can be determined with a simple spirometer.