Two hundred eighteen healthy children aged 2 to 18 years were studied using a modification of the forced oscillation technique. Reference values with height as predictor were determined for total respiratory resistance and impedance during inspiration, expiration, and throughout the whole respiratory cycle at an oscillation frequency of 4 Hz and, in a subpopulation of 61 children, at frequencies of 2 and 12 Hz. Mean total inspiratory resistance, determined at 4 Hz, decreased with growth from 1.3 kPa X 1(-1) X s at 2 years of age to 0.3 kPa X 1(-1) X s at 18 years. Variability in the results between individuals, expressed in terms of coefficient of variation, was found to be +27% and -21%, respectively, and within individuals, 9%. Resistance during expiration was on average 16% higher than during inspiration and the variability within individuals was 11%. A marked decrease in resistance was found in small children when the frequency was increased from 2 to 12 Hz. The frequency dependence of respiratory resistance observed in small children changes gradually with growth, in parallel with the reduction of total respiratory resistance, to an adult pattern in which no significant change in resistance can be noted between frequencies of 2 and 12 Hz.

Adolescent↗

PubMedDate not supplied

Effects of electric arc welding on ventilatory lung function.

Respiratory symptoms, spirometry, forced expiratory flows, and the nitrogen closing volume test were studied in 119 welders and 90 controls, matched with respect to age, height, and smoking habits. Respiratory symptoms according to a questionnaire were more prevalent in the welders. No short-term changes of the measured variables during the day or week attributable to welding were found in twenty-one nonsmoking welders. Compared to the controls, closing volume and closing capacity (i. e., closing volume + residual volume) were significantly higher, and total lung capacity and the amplitude of the cardiogenic oscillations in the nitrogen curve were significantly lower in the welders who were nonsmokers or exsmokers, whereas there were no differences among smokers. These findings in welders may be attributable to deposition of welding fume particles in peripheral small airways or alveoli.

Aerosols↗

PubMedDate not supplied

New mobilization and laterofixation procedure for cricoarytenoid joint ankylosis in rheumatoid arthritis.

Ankylosis of the cricoarytenoid joints due to rheumatoid arthritis can cause severe laryngeal obstruction. With a mobilization and laterofixation procedure, five of six patients were successfully operated upon. Documented improvement of breathing was achieved and the voice function was acceptable after decannulation.

Adult↗

PubMedDate not supplied

Glucose and insulin infusion directly after cardiac surgery: effects on systemic glucose uptake, catecholamine excretion, O2 consumption, and CO2 production.

Systemic glucose uptake was studied in 31 patients during 4 hr starting 1 hr after open heart surgery, using the hyperinsulinemic "clamp" technique at different plasma insulin levels and at a glucose concentration of 6 or 10 mmol/liter. Possible metabolic side effects related to the glucose uptake were studied by measurements of urinary catecholamine excretion, O2 consumption, CO2 production, and arterial PCO2. A peak systemic glucose uptake of 7.0 +/- 0.4 mg/kg body weight/min was found at a plasma insulin concentration of 3192 +/- 150 mU/liter and a blood glucose concentration of 10.2 +/- 0.1 mmol/liter. No significant difference was found in urinary catecholamine excretion compared to control patients. O2 consumption was unaltered while a 15% increase in CO2 production was observed.

Adult↗

PubMedDate not supplied

Laryngeal obstruction after Teflon injection.

Respiratory effects of injection of teflon were studied in twelve patients with unilateral vocal cord paralysis by determination of the orolaryngeal airway resistance (Rol). Ordinary spirometry and flow volume loops were also performed but were found to be less adequate than determination of Rol. Within the first week postoperatively, Rol increased by on average about 75%. Only one patient had clinical symptoms of laryngeal obstruction. One month after the injection of teflon, Rol was in all patients the same as preoperatively. It is concluded that teflon injection should be used with caution in patients with severe respiratory impairment but could be used without fear of induced future respiratory effects in patients with progressive pulmonary disease.

Adult↗

PubMedDate not supplied

Effects of glypressin on human nasal mucosa.

The effect of intravenous and topical glypressin, a triglycyl hormonogen of vasopressin, on the nasal mucosa was evaluated in healthy subjects. A dose-dependent reduction of nasal blood flow resulted from both intravenous and topical glypressin. The effect of the latter in gel form lasted 2 hours. Glypressin was also found to decongest the nasal mucosa. Topical application of glypressin gel might be an alternative to conventional treatment with intranasal packing in nose-bleed.

Administration, Intranasal↗

PubMedDate not supplied

Reflex activation in allergen-induced nasal mucosal vascular reactions.

Subjects with allergic rhinitis were challenged unilaterally with diluent and increasing doses of allergen. Challenge with the highest dose of allergen was also carried out after topical anesthesia of the nasal cavity using lidocaine. In the contralateral, unprovoked nasal cavity the mucosal blood flow was determined using the 133Xenon wash-out technique and the nasal airway resistance was determined by rhinomanometry before and after challenge. Nasal symptom scores were estimated 15 min after each challenge. Blood flow in the nasal mucosa in the unprovoked right nasal cavity decreased in a dose-dependent manner for th two highest doses of allergen where a reduction of 21% (p less than 0.05) and 26% (p less than 0.01) was obtained. Nasal airway resistance increased somewhat after the highest dose (p greater than 0.05). Topical anesthesia in the provoked nasal cavity inhibited the decrease in blood flow in the unchallenged nasal cavity. These findings suggest that the changes in the tone of the resistance vessels, but not the capacitance vessels, which are induced by allergen, are largely reflex-mediated.

Adult↗

PubMedDate not supplied

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.

Aged↗

PubMedDate not supplied

Day-to-day variation of bronchodilatory response to an inhaled beta-2-stimulant in asthmatics.

The effect of inhaling 0.25 and 2.0 mg of terbutaline sulphate, a beta-2-stimulant, from a metered dose aerosol was studied in five asthmatic patients during two periods of five days each. During the first period, the patients used a good spontaneous inhalation technique; during the second period, the inhalation technique was optimized and controlled. The variation of basal FEV1 and of the increase (delta FEV1) caused by 0.25 mg of inhaled terbutaline was considerable. The effect was only slightly better and the variation only slightly smaller when the controlled inhalation technique was used. The differences were not significant. In individual patients, there was no or negative correlation between delta FEV1 and the corresponding basal FEV1 value. Accordingly, the most commonly used way of expressing delta FEV1 as a percentage of basal FEV1 value was found to be insensitive. Delta FEV1, expressed as a percentage of the maximum available FEV1 increase on the same day after 2.25 mg terbutaline sulphate, was found to be most sensitive. This way of expressing delta FEV1 will increase the possibilities of detecting differences between treatments in clinical trials.

Administration, Inhalation↗