Treatment of upper airway obstruction associated with goiter

The authors examined the resolution of spirometric indices of upper airway obstruction (UAO) following surgical treatment for goiter. The results of a recent study suggest that the integrity of the upper airway remains intact but prolonged recovery is required.     

Pulmonary edema as a result of chronic upper airway obstruction

This is the first case of an adult who developed recurrent pulmonary edema as a result of unrecognized chronic upper airway obstruction due to polyarticular juvenile rheumatoid arthritis. The case highlights the importance of considering upper airway involvement in the differential diagnosis of sedentary patients with arthritic joint disease and breathing difficulties.     

Functional upper airway obstruction and chronic irritation of the larynx

Wheezing and dyspnoea are typical symptoms of asthma but can also be found in diseases of the extrathoracic airways. Functional upper airway obstruction may imitate, as well as complicate asthma. Functional upper airway obstruction was first described as a conversion disorder in young females with inspiratory stridor. Subsequently, it was found that functional upper airway obstruction was more often a secondary phenomenon in chronic asthma also involving the expiratory laryngeal airflow. During a period of 15 months, we diagnosed six cases of functional upper airway obstruction. Five patients were female and one male, and four were also asthmatics. Three cases showed chronic sinusitis with postnasal drip (PND) and/or gastro-oesophageal reflux. Both disorders may irritate the larynx. Treatment of sinusitis and gastro-oesophageal reflux led to a significant improvement of dyspnoea in all three of these patients. In asthma refractory to treatment and in the case of an asthmatic exacerbation without obvious cause, functional upper airway obstruction should be excluded to avoid unnecessary treatment with systemic steroids. Some of the possible causative factors of functional upper airway obstruction, such as postnasal drip and gastro-oesophageal reflux, are easily treatable.     

Emergency use of the laryngeal mask airway in severe upper airway obstruction caused by supraglottic oedema

We report two cases of severe upper airway obstruction caused by supraglottic oedema which developed rapidly at the time of anaesthesia. Conventional methods to relieve the obstruction failed and it was only overcome when a laryngeal mask airway (LMA) was inserted and positive pressure applied manually during inspiration. In one case a fibrescope was passed via the LMA and this revealed two cushions of oedematous false vocal cords protruding into the bowel of the LMA which were pushed out of the way when positive pressure was applied during inspiration. We believe that the LMA should be considered in the emergency management of severe upper airway obstruction even when this involves supraglottic oedema.     

Tracheobronchial stenting for the treatment of airway obstruction

A wettability gradient was prepared on lowdensity polyethylene (PE) sheets by treating them in air with a corona from a knife-type electrode the power of which increased gradually along the sample length. The PE surfaces oxidized gradually with the increasing corona power and a wettability gradient was created on the surfaces, as evidenced by the measurement of water contact angles, Fourier transform infrared spectroscopy in the attenuated total reflectance mode, and electron spectroscopy for chemical analysis. The wettability gradient surfaces prepared were used to investigate the adhesion behavior of platelets in the absence and presence of plasma proteins in terms of the surface hydrophilicity/hydrophobicity of polymeric materials. The platelets adhered to the wettability gradient surfaces along the sample length were counted and examined by scanning electron microscopy (SEM). It was observed that the platelet adhesion in the absence of plasma proteins increased gradually as the surface wettability increased along the sample length. The platelets adhered to the hydrophilic positions of the gradient surface also were more activated (possessed more pseudo pods as examined by SEM) than on the more hydrophobic ones. However, platelet adhesion in the presence of plasma proteins decreased gradually with the increasing surface wettability; the platelets adhered to the surface also were more activated on the hydrophobic positions of the gradient surface. This result is closely related to plasma protein adsorption on the surface. Plasma protein adsorption on the wettability gradient surface increased with the increasing surface wettability. More plasma protein adsorption on the hydrophilic positions of the gradient surface caused less platelet adhesion, probably due to platelet adhesion inhibiting proteins, such as high-molecular-weight kininogen, which preferably adsorbs onto the surface by the so-called Vroman effect. It seems that both the presence of plasma proteins and surface wettability play important roles for platelet adhesion and activation.     

Differential effects of nasal continuous positive airway pressure on reversible or fixed upper and lower airway obstruction

Our study was to assess whether there were differential effects of nasal continuous positive airway pressure (nCPAP) on different kinds of obstruction in either upper or lower airways in patients with chronic obstructive pulmonary disease (COPD). nCPAP (6 cmH2O for ten minutes) was applied to 7 patients with reversible extrathoracic upper airway obstruction (RUAO) and 3 patients with fixed extrathoracic upper airway obstruction (FUAO). Eighteen stable asthmatics, receiving methacholine challenge to induce a more than 20% reduction in FEV1, were randomly investigated for the effect of nCPAP or sham pressure on reversible lower airway obstruction. Nine stable COPD patients were enrolled to study the effect on irreversible lower airway obstruction. Maximal expiratory and inspiratory flow volume curves and dyspnoea scores were obtained before and after immediate withdrawal of nCPAP. In the RUAO group, nCPAP significantly improved stridor and dyspnoea scores, decreased the ratio of FEF50/FIF50 from 2.05 +/- 0.25 to 1.42 +/- 0.16, and increased peak inspiratory flow (PIF) as well as forced inspiratory vital capacity by 26 +/- 8% and 9 +/- 4%, respectively. In expiratory phase, there was no significant change in pulmonary functions. In asthmatics, nCPAP significantly reversed methacholine-induced bronchoconstriction increasing forced vital capacity by 10 +/- 3%, FEV1 by 15 +/- 4% and PIF by 32 +/- 11%. nCPAP significantly increased the response to bronchodilators. The improvement in airflow rate persisted for at least 5 min after nCPAP withdrawal and was highly correlated with the response to bronchodilators. There was no significant effect of nCPAP on airflow rate in COPD patients. Subjective dyspnoea score changes paralleled the pulmonary function improvement. We conclude that there are differential effects of nCPAP on airflow rates in patients with different nature of airway obstruction. Patients with airway obstruction caused by structural changes may not benefit from the use of nCPAP in improving airflow rates.     

Children with nocturnal upper airway obstruction: postoperative orthodontic and respiratory improvement

The effect of pravastatin, an inhibitor of p21ras isoprenylation, on hepatocarcinogenesis induced by N-nitrosomorpholine and on p21ras isoprenylation were investigated in male Sprague-Dawley rats. Rats received i.p. injections of pravastatin (10 and 20 mg kg(-1) body weight) every other day and, from the beginning of the experiment, were given drinking water containing N-nitrosomorpholine for 8 weeks. Visible white nodules and hepatic lesions staining positively for gamma-glutamyl transpeptidase or glutathione-S-transferase, placental type, were examined macroscopically or histochemically. In week 15, pravastatin at both dosages significantly reduced the incidence, number and volume of visible white nodules. Quantitative histological analysis also showed that prolonged administration of pravastatin at both dosages resulted in significant reductions in the number and percentage area of hepatic lesions positive for gamma-glutamyl transpeptidase and glutathione-S-transferase, placental type. Administration of pravastatin also significantly decreased the amount of membrane-associated p21ras in the tumour and the labelling index of neoplastic nodules and increased the apoptoic indices of neoplastic nodules. These findings indicate that pravastatin suppresses hepatocarcinogenesis and suggest that this effect might be related to pravastatin's inhibition of p21ras isoprenylation and its subsequent inhibition of cell proliferation and induction of apoptosis in neoplastic lesions.     

Exercise-induced airway obstruction

Exercise is one of the most common precipitants of acute asthma encountered in clinical practice. This article examines the prevalence of this condition. Topics discussed include historical review, current concepts of pathogenesis, clinical features, late reactions, diagnosis, and therapy.     

Sleep apnea, hypersomnolence, and upper airway obstruction secondary to adenotonsillar enlargement

The authors examined four children with substantial adenotonsillar enlargement that caused intermittent severe upper airway obstructive episodes, documented by all-night polygraphic monitoring of sleep and respirations. Previously unreported complications of severe adenotonsillar enlargement that were demonstrated included prolonged obstructive apneic episodes and disturbed sleep patterns. The children also exhibited daytime hypersomnolence. Polygraphic sleep studies after adenotonsillectomy confirmed improved sleep patterns and relief of the obstructive episodes. None of our patienqs had developed pulmonary hypertension, cor pulmonale, or other reported complications of prolonged upper airway obstruction, all of which may have been averted by early diagnosis and treatment.     

The outcome of patients with upper airway obstruction transported to a regional paediatric intensive care unit

Two cases of nodular hidradenoma of the breast with possibly different origins are reported. Case 1 is of a 58-year-old female with a breast mass in the left, outer lower-quadrant. A histogenetical origin in the skin adnexal glands was suspected due to its superficial location and immunohistochemical findings. Case 2 is of a 44-year-old male with a subareolar nodule and nipple discharge. Histological examination demonstrated that the tumor was located deep in the breast tissue, was surrounded by dilated mammary ducts and exhibited intraductal extensions, which are all features mimicking those of breast cancer. Immunohistochemical positivity against gross cystic disease fluid protein-15 was weakly identified and negativity for endoplasmic reticulum was observed. This case can be interpreted as arising in the mammary ducts. It is well known that various kinds of skin adnexal tumors arise in the breast tissue; however, nodular hidradenoma of the breast is still a rare benign neoplasm. Clinically, nodular hidradenoma of the breast tends to occur in the nipple or subareolar region of the female breast. It should be kept in mind that nodular hidradenoma may occur in mammary ducts and it should be included when differential diagnoses are made of subareolar breast tumors.     

Postesophagectomy mediastinal chylothorax causing upper airway obstruction misdiagnosed as asthma: a report of two cases

Injury to the thoracic duct resulting in chylothorax is an uncommon but well-documented complication of esophagectomy. In two cases, which were associated with signs of life-threatening upper airway obstruction, an initial diagnosis of asthma was made. It appears that this complication of esophagectomy has not been reported previously.     

Aerosol deposition and airway obstruction

Intrapulmonary deposition of 1-mum-diameter particles of dioctyl sebacate was studied in 58 working coalminers. Total deposition was found to be significantly correlated with lung function measurements characterizing airway obstruction. The closest relationship was between deposition and the mean maximal flow rate in the third quarter of a forced expiration. The shape of the exhaled aerosol recovery curve was also found to be related to the degree of airway obstruction; 3 basic types are described. The concave type was more common in smokers, in whom deposition was significantly greater. The presence of simple pneumoconiosis was not associated with the degree of aerosol deposition. The significance of the findings of aerosol deposition and its recovery pattern are discussed in relation to the pathogenesis of lung disease.     

Late-onset life-threatening angioedema and upper airway obstruction caused by angiotensin-converting enzyme inhibitor: report of a case

Angioedema is a rare but potentially lethal adverse effect when associated with upper airway obstruction. Sporadic cases of angioedema secondary to angiotensin converting enzyme inhibitors (ACEI) have been reported in the literature. The overall incidence is around 0.1% to 0.2%, and the time of onset is usually during the first week of ACEI therapy. Late-onset angioedema secondary to treatment with ACEIs is much more frequent than appreciated, and is largely unrecognized because of the absence of temporal correlation between ACEI therapy and the development of angioedema. Since angioedema may progress to upper airway obstruction, otolaryngologists must be aware of this association. Most importantly, late-onset angioedema should alert the clinician to discontinue the ACEI immediately to prevent further morbidity. This report presents an example of late-onset angioedema which was precipitated by taking a double dose of captopril incidentally. The case is discussed, and the literature, pathophysiology and treatment of angioedema are reviewed.     

Mechanical airway obstruction secondary to retropharyngeal haematoma

Mechanical airway obstruction secondary to retropharyngeal haematoma is a life-threatening emergency and should be anticipated in all cervical spine injure patients regardless of the severity of trauma. Most retropharyngeal haematomas described in the literature have involved complicating factors such as anticoagulant therapy, tumour, aneurysm, infection or major cervical spine injury. Several authors have however described haematomas causing airway compromise with minor hyperextension injuries. We describe the case of a 19-year-old male who was involved in a motorcycle accident. He sustained an atlanto-occipital fracture-dislocation and a very large retropharyngeal haematoma which resulted in airway obstruction and a subsequent difficult intubation. We outline the normal anatomy of the retropharyngeal space, the pathogenesis of retropharyngeal haematomas, and outline techniques of intubation available.     

Upper airway obstruction induced by warfarin sodium

I report a patient in whom warfarin sodium induced upper airway obstruction secondary to a spontaneous nontraumatic hemorrhage into the sublingual space. Treatment of this obstructive sublingual space hematoma with conservative medical management is reviewed. I discuss the role of warfarin sodium in coagulation and in the production of this pseudo-Ludwig phenomenon.     

Tidal expired airflow patterns in adults with airway obstruction

Earlier studies have shown that time and flow indices derived from tidal expiratory flow patterns can be used to distinguish the severity of airway obstruction. This study was designed to address two aspects of tidal expiratory flow patterns: 1) how do expiratory flow patterns differ between subjects with normal and obstructed airways; and 2) can a sensitive index of airway obstruction be derived from these pattern differences? Tidal expiratory flow patterns from 66 adult subjects with varying degrees of airway obstructive disease with a forced expiratory volume in one second (FEV1) of 20-121% predicted were examined. In each subject, the expired flow pattern from each consecutive breath was scaled and then averaged together to create a single expired pattern. A detailed examination of the scaled flow patterns in 12 subjects (six with normal airways and six with airway obstruction) showed that the shape of the post-peak expiratory flow portion was different in the subjects with airway obstruction. A slope index, S, was derived from the scaled patterns and found to be sensitive to the severity of airway obstruction, correlating with FEV1 (% pred) with r2=0.74 (p<0.05, n=57). The S index also correlated (r2=0.36, p<0.05, n=47) with the functional residual capacity (FRC) (% pred) which was >100% in subjects with severe airway obstruction and lung overinflation. In subjects with normal airways, three further airflow patterns could be distinguished, which were different from the patterns seen in subjects with the severest airway obstruction. Scaled flow patterns from tidal expiration collected from uncoached subjects, can be used to derive an index of airway obstruction.