Upper airway anesthesia induces airflow limitation in awake humans.

Upper airway receptors are thought to contribute to upper airway stability by reducing collapsing forces. Their activity can be abolished by topical anesthesia. We have measured in 16 healthy volunteers (mean +/- SD age, 23.7 +/- 1.6 yr) specific airway conductance (SGaw), maximal inspiratory (MIFR) and expiratory (MEFR) flow rates before and 15, 35, and 45 min after extensive upper airway anesthesia (UAA) with 10% lidocaine. Average values of MIFR decreased (p less than 0.01) 15 min after UAA, but they returned to or near to control values at 45 min: MIF25 (4.8 versus 6.0 L/s); MIF50 (5.1 versus 6.2 L/s); MIF75 (4.4 versus 5.3 L/s). Transient decreases in flow (V) rates, reaching zero flow in some subjects, were observed in 13 subjects during forced inspiratory vital capacity (FIVC) maneuvers and in seven subjects during forced expiratory vital capacity (FEVC) maneuvers. MEFR at 25, 50, and 75% FVC, SGaw, and FVC did not change after anesthesia. Simultaneous measurements of supraglottic pressure, V, and lung volume in 12 of the 16 subjects showed that the site of flow limitation was localized at the level of the glottis in all except one subject in whom there was both a glottic and a supraglottic obstruction. We conclude that extensive upper airway anesthesia induced a profound but transitory upper airway obstruction during FIVC and FEVC maneuvers. These findings are compatible with the concept of reflex regulation of upper airway caliber.     

The effect of spinal anesthesia on pulmonary function tests in old patients

Pulmonary function test (PFT) results are mainly dependent on age, sex, height, weight, pulmonary mechanics disturbances and cooperation of the subjects. The position and anesthesia type may also influence the PFT results. In this study we aimed to evaluate spirometric changes in old and young patients who performed spinal anesthesia. Fifty patients performed spinal anesthesia were randomized in two groups: Group 1 (n= 25) aged 60-85 years old and group 2 (n= 25) aged 20-59 years old. After electrocardiography, noninvasive blood pressure and peripheral oxygen saturation (SpO2) monitorization, spinal anesthesia using 0.5% hyperbaric bupivacain from L 3-4 intervertebral space was applied. Sensory block levels, hemodynamics and PFT such as forced vital capacity (FVC), forced expiratory volume/1 second (FEV(1)), peak expiratory flow (PEF), and forced expiratory flow at the 25 and 75% of the pulmonary volume (FEF(25-75)) were performed before and after spinal anesthesia in 10th, 40th and 100th minutes in supine and 30 degrees head position using hand type spirometry. Wilcoxon paired two tests statistical analysis was used to compare PFT changes of the subjects. Mean arterial blood pressure levels and spirometric measurements of FVC, FEV(1) and FEF25-75 decrease with respect to basal values in 40th minutes was significant in old patients whom spinal anesthesia was over Th6 level but in young patients the changes were not significant. PFT decrement probabilities should be taken in account in old patients supposing for spinal anesthesia and be paid attention for high level spinal blocks in risk group patients.     

Airflow limitation and breathing strategy in congestive heart failure patients during exercise

BACKGROUND: Congestive heart failure (CHF) patients experience dyspnea on exertion and therefore have decreased exercise tolerance. OBJECTIVE: This study explores the hypothesis that stable New York Heart Association (NYHA) class III CHF patients without a history of pulmonary disease exhibit airflow limitation with increasing exercise. METHODS: We characterized flow limitations and breathing reserves at baseline, during exercise before anaerobic threshold (pre-AT), and after anaerobic threshold (post-AT) in CHF patients and normal subjects. Data were collected in the form of maximal flow volume loops and subsequent tidal flow volume loops at baseline and during exercise. Expiratory flow limitation was expressed as percent of tidal volume that corresponded with overlap of the tidal flow volume loops and maximal flow volume loops during expiration. The area directly between the maximum flow volume loops and the tidal flow volume loops during the expiratory phase is expressed as expiratory flow volume reserve (EFVR). RESULTS: CHF patients experienced expiratory flow limitation during exercise (pre-AT and post-AT) that was significantly increased compared to baseline and to normal subjects at similar exercise levels (CHF, baseline 8.5 +/- 7, pre-AT 37 +/- 10, post-AT 38 +/- 8%, n = 9, p < 0.05). Both CHF patients and normal subjects increased EFVR during exercise, but only the normal subjects increased EFVR to a significantly different value at post-AT exercise levels (normal subjects, 9.5 +/- 2, 11 +/- 2, 32 +/- 4%, n = 7, p < 0.05). Both CHF patients and normal subjects increased end inspiratory lung volume (EILV) during exercise, but only the normal subjects significantly increased EILV at post-AT exercise levels (normal subjects, 49 +/- 4, 55 +/- 5, 76 +/- 4%, p < 0.05). Inspiratory capacity (IC)/forced vital capacity (FVC) ratios were increased in CHF patients compared to normal subjects. However, IC/FVC values did not change during exercise in either group. CONCLUSIONS: CHF patients cannot utilize their full respiratory capacity during exercise secondary to expiratory flow limitation and an inability to increase EILV and EFVR.     

Airway anesthesia during positive and negative inspiratory pressure breathing in man.

We have measured the effects of airway anesthesia (aerosolized 5% lidocaine) on the respiratory pattern during positive or negative inspiratory pressure in 8 resting subjects. The subjects breathed through a 600 ml dead space (peak inspiratory airway pressure, Paw = -2 cmH2O) without or with negative (approx. -5 or -10 cmH2O) or positive (approx. +5 or +10 cmH2O) inspiratory pressure, provided by a laminar flow resistance or a positive pressure source, respectively. Control measurements were performed before and after measurements with airway anesthesia. Measurements included tidal volume, respiratory frequency, ventilation, inspiratory and expiratory duration, occlusion pressure (P0.1) and end-tidal PCO2. None of the parameters measured was significantly altered by airway anesthesia, which was effective in suppressing the cough reflex. We conclude that information from lung afferents that are suppressed with the elimination of the cough reflex is not important for the breathing pattern during resting ventilation with elevated tidal volume (dead space load) and with positive or negative inspiratory pressure.     

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.     

Effects of inhaled lidocaine on exercise-induced asthma

Experiments were performed to determine if stimulation of afferent nerve endings in the respiratory mucosa plays a major role in the initiation of exercise-induced asthma. Five asthmatic subjects were studied in two sessions of 10 min treadmill exercise using an identical workload. In the control session the subjects were exercised without treatment; in the other session aerosol lidocaine (1.5 mg/kg) was inhaled from residual volume to total lung capacity before exercise was started. Pulmonary function tests were measured (1) to obtain baseline values before the aerosol inhalation or exercise was commenced, (2) 2-3 min after completion of lidocaine inhalation, and (3) 4 min after termination of exercise. In the control session the mean postexercise forced expiratory volume in 1 s (FEV1) and the mean forced expiratory flow during the middle half of forced vital capacity (FEF25-75%) were decreased to 61 and 44% of the baseline values, respectively. Similarly, with the lidocaine treatment the post-exercise FEV1 and FEF25-75% were decreased to 54 and 44% of the baseline values, respectively. These data indicate that the afferent nerves in the respiratory mucosa may not play a critical role in the development of exercise-induced asthma.     

The flow-volume loop during glossopharyngeal breathing

The flow-volume loops of three patients with chronic poliomyelitis were examined during glossopharyngeal breathing and compared with those during forced vital capacity maneuvers using only chest wall muscles. Peak expiratory flow rates and vital capacities were greater in all subjects after inspiration using glossopharyngeal breathing. During glossopharyngeal breathing, there was a progressive fall in the inspiratory flow rate and volume of each stroke as pulmonary volume increased.     

Kurtosis and skewness of density histograms on inspiratory and expiratory CT scans in smokers

The aim of this study is to evaluate the relationship between lung function and kurtosis or skewness of lung density histograms on computed tomography (CT) in smokers. Forty-six smokers (age range 46?81 years), enrolled in the Lung Tissue Research Consortium, underwent pulmonary function tests (PFT) and chest CT at full inspiration and full expiration. On both inspiratory and expiratory scans, kurtosis and skewness of the density histograms were automatically measured by open-source software. Correlations between CT measurements and lung function were evaluated by the linear regression analysis. Although no significant correlations were found between inspiratory kurtosis or skewness and PFT results, expiratory kurtosis significantly correlated with the following: the percentage of predicted value of forced expiratory volume in the first second (FEV(1)), the ratio of FEV(1) to forced vital capacity (FVC), and the ratio of residual volume (RV) to total lung capacity (TLC) (FEV(1)%predicted, R = -0.581, p < 0.001; FEV(1)/FVC, R = -0.612, p < 0.001; RV/TLC, R = 0.613, p < 0.001, respectively). Similarly, expiratory skewness showed significant correlations with PFT results (FEV(1)%predicted, R = -0.584, p < 0.001; FEV(1)/FVC, R = -0.619, p < 0.001; RV/TLC, R = 0.585, p < 0.001, respectively). Also, the expiratory/inspiratory (E/I) ratios of kurtosis and skewness significantly correlated with FEV(1)%predicted (p < 0.001), FEV(1)/FVC (p < 0.001), RV/TLC (p < 0.001), and the percentage of predicted value of diffusing capacity for carbon monoxide (kurtosis E/I ratio, p = 0.001; skewness E/I ratio, p = 0.03, respectively). We conclude therefore that expiratory values and the E/I ratios of kurtosis and skewness of CT densitometry reflect airflow limitation and air-trapping. Higher kurtosis or skewness on expiratory CT scan indicates more severe conditions in smokers.     

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.     

Mixed infiltrative and obstructive disease on high-resolution CT: differential diagnosis and functional correlates in a consecutive series

Fourteen of 400 consecutive patients having high-resolution computed tomography (HRCT) with expiratory images showed findings of infiltrative lung disease on inspiratory HRCT and air trapping on expiratory CT. Diagnoses included hypersensitivity pneumonitis, sarcoidosis, atypical infection, and pulmonary edema. The extent of infiltrative abnormalities and air trapping were correlated with pulmonary function tests (PFT) in 11 patients. PFT indicated a mixed pattern in five, an obstructive pattern in three, and a restrictive pattern in three. Forced expiratory volume (FEV) in 1 second/forced vital capacity (FVC) correlated significantly with the extent of air-trapping (r = 0.60; p = 0.05). The extent of infiltrative abnormalities correlated significantly and negatively with forced vital capacity (r = -0.82, p = 0.002), FEV1 (r = -0.59, p = 0.05), total lung capacity (TLC) (r = -0.67, p = 0.05), and DLCO (r = -0.75, p = 0.02). Findings of lung infiltration on inspiratory HRCT scans and air trapping on expiratory CT correlated respectively with PFT measures of restrictive and obstructive lung disease.     

Functional laryngeal obstruction relieved by panting

A 49-year-old man presented with a two-day history of severe recurrent dyspnea and inspiratory stridor. A chest roentgenogram, computed tomographic scan of the neck, direct laryngoscopy, and bronchoscopy excluded organic upper airway obstruction. Laryngospasm occurred during the bronchoscopy. Although flow volume loops revealed severe upper airway obstruction (inspiratory and expiratory), airway resistance measured plethysmographically (during panting) was normal. Because of this observation, panting was recommended for relief of the patient's recurrent attacks of functional laryngeal obstruction. The panting maneuver immediately and completely relieved all 25 to 30 subsequent attacks. After the patient recovered clinically, a flow volume loop was repeated and was found to be normal. The marked discrepancy between severe flow limitation (as detected by flow volume loops) and normal airway resistance (measured plethysmographically) may be a diagnostic test for functional laryngeal obstruction, and panting may be an effective emergency measure for its relief. Relief by panting may also suggest the diagnosis. A second patient with an almost identical symptom complex is described, in whom the panting maneuver was also dramatically successful in promptly aborting recurrent severe attacks of airway obstruction and stridor.     

Pulmonary function changes in children after transcatheter closure of atrial septal defect

This study was performed to assess changes in pulmonary function test (PFT) and pulmonary outcome after transcatheter closure of atrial septal defect (ASD) in pediatric patients. A total 55 pediatric patients undergoing transcatheter ASD closure received PFT at baseline (day before ASD closure), and at 3 days and 6 months after procedure. Forced vital capacity (FVC), forced expired volume in 1 sec (FEV₁), FEV₁ to FVC ratio (FEV₁/FVC), peak expiratory flow (PEF), and mean forced expiratory flow during the middle half of FVC (FEF_25–75) were measured. Individually, subjects were classified by spirometry as normal, obstructive or restrictive, to evaluate the effect of transcatheter closure on pulmonary outcome. These 55 children had significantly reduced mean PEF and FEF_25–75 (84 ± 24%, P = 0.040 and 76 ± 22%, P = 0.010, respectively) at baseline, with FEF_25–75 reduced significantly at 3 days and 6 months (78 ± 24%, P = 0.010 and 81 ± 24%, P = 0.040, respectively) after transcatheter closure. Six months after transcatheter closure of ASD, significant improvement was observed in mean FVC (94 ± 19% vs. 98 ± 15%, P = 0.034) and FEV₁ (90 ± 20% vs. 96 ± 19%, P = 0.008). Assessed individually, better pulmonary outcome was found in patients without pulmonary hypertension (PH) (χ² = 8.333, P = 0.044). PFT disturbance was observed in significant flow limitation in the peripheral airway of ASD patients. Improved PFT was found after transcatheter closure and better pulmonary outcome was observed in patients without PH. ASD children need monitoring pulmonary function and should receive transcatheter closure before PH develops. Pediatr Pulmonol. 2009; 44:1025–1032. ©2009 Wiley‐Liss, Inc.     

Effects of antithyroid medication on the flow-volume loop in patients with hyperthyroidism

This prospective study was designed to evaluate the effects of hyperthyroidism on flow-volume loops in nonasthmatic 20 patients with hyperthyroidism. Thyroid related hormones (Total T3, Total T4 and TSH), thyroid gland volumes with ultrasonography, circumference of neck values and flow-volume loops were obtained at the beginning and after three months of antithyroid treatment. Propylthiouracil treatment was followed by a statistically significant decrease in thyroid gland volume and circumference of neck (p< 0.001 and p< 0.001, respectively). The most significant result was improvement of maximum midexpiratory flow rate (MMEFR) after propylthiouracil therapy for three months (p= 0.003). Increases in mean forced expiratory flow after 25% of FVC has been exhaled (FEF25), mean forced expiratory flow after 75% of FVC has been exhaled (FEF75) values were found consistent with the overall improvement in expiratory flow parameters (p= 0.044, p= 0.012 respectively). In conclusion, we speculated that improvement of expiratory flow parameters might be the earlier changes in flow volume loops of patients who were treated with propylthiouracil for hyperthyroidism.     

Prediction equations for pulmonary function values in healthy young Iranians aged 8-18 years

OBJECTIVE: Pulmonary function test (PFT) variables are dependent on height, age and gender. In addition, there is evidence of PFT variation in different ethnic groups. Prediction equations for PFT from a healthy, non-smoking, urban young population in the city of Mashhad (north-east Iran) have been derived. METHODOLOGY: Prediction equations for normal pulmonary function were derived from 336 healthy, non-smoking subjects, including 187 males (height 103-188.5 cm) and 149 females (height 104-183 cm) aged 8-18 years. The subjects underwent measurement of spirometric flow and volume. The following variables were measured: FVC, FEV1, maximal mid-expiratory flow (MMEF), PEF, maximal expiratory flow at 75, 50 and 25% of the FVC (MEF75, MEF50, and MEF25, respectively), tidal volume (VT), inspiratory reserve volume (IRV), expiratory reserve volume (ERV), inspiratory capacity (IC), and vital capacity (VC). Regression analysis using height and age as independent variables was applied to provide predicted values for both genders. RESULTS: There were positive correlations for each pulmonary function variable with height and age. The largest positive correlations were found for FEV1 with height and age, in both genders. Comparison of PFT variables derived from the equations obtained in the present study showed significant differences to those calculated from several previously published equations (P < 0.001 for most variables). For example, the values of FVC and FEV1 derived from the equations obtained in the present study were 2.83 +/- 0.99 and 2.50 +/- 0.89 for males, and 2.41 +/- 0.54 and 2.19 +/- 0.53 for females, while the values derived from the equations of the European Community for Steel and Coal study were 3.12 +/- 1.06 and 2.62 +/- 0.89 for males and 2.79 +/- 0.67 and 3.35 +/- 0.57 for females, respectively. CONCLUSIONS: A set of PFT reference values and prediction equations for both genders has been derived using a relatively large, healthy, non-smoking Iranian young population, and has generated results that differ from several other prediction equations.     

Correlation between symptom score, wheeze, reversibility of pulmonary function tests and treatment response in asthma

Asthma management is a major concern because some asthmatic patients either do not respond or else hardly respond to treatment. Therefore in the present study, an attempt has been made to determine the predictors of treatment response in asthmatic patients. Thirty six asthmatic adults including 13 male and 23 female were studied during a 3 month treatment period. Asthma symptom score (SS) and wheezing were recorded before and after treatment. Pulmonary function tests (PFTs) including forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), maximal expiratory measured at the beginning and the end of the study. The increase in PFT values 10 mm after 200 ?,tg inhaled salbutamol (in percentage) was considered as reversibility in airway constriction. There were significant improvements in SS (p相似文献   

Impact of a physical rehabilitation program on the respiratory function of adolescents with idiopathic scoliosis

BACKGROUND: Idiopathic adolescent scoliosis (AIS) causes not only spinal deformities but rib cage abnormalities that lead to abnormal volumes and pulmonary capacity on pulmonary function testing (PFT). The objective of this study was to analyze the impact of a physical rehabilitation program on respiratory function in surgical patients with AIS. METHODS: From October 2003 to October 2004, a total of 34 patients (age range, 10 to 18 years) presenting with AIS and a thoracic curvature between 45 degrees and 88 degrees were studied prospectively at a tertiary academic hospital. The patients underwent clinical and radiographic evaluations of the vertebral deformity, chest radiographs, PFT, evaluation of peak expiratory flow, and 6-min walk tests (6MWTs) before and after joining a physical rehabilitation program for 4 months. RESULTS: An improvement in FVC, inspiratory capacity, FEV(1), expiratory reserve volume, and performance assessed by 6MWT were observed after rehabilitation. CONCLUSIONS: Global conditioning improved after the rehabilitation program. This was expressed by both PFT and 6MWT results.     

Alveolar pressure and airway resistance during maximal and submaximal respiratory efforts

A digital computing technique was used to extract continuous calculations of average alveolar pressure and airway resistance from body plethysmographic measurements during forced inspiratory and expiratory vital capacity maneuvers and tidal breathing in human subjects. Derived alveolar pressures were similar to those obtained using an interrupter technique (linear regression slope, 0.99 +/- 0.02; r = 0.98) and by comparison with esophageal pressure measurements. Studies in normal subjects revealed a characteristic pattern of increasing airway resistance throughout the expiratory phases of maximal and submaximal respiratory maneuvers, with maximal resistance of 33 to 110 cm H2O/L/s at low lung volumes during forced vital capacities. In contrast, inspiratory resistance remained low and constant throughout maximal and submaximal inspiratory maneuvers. Patients with COPD showed substantially higher inspiratory and expiratory resistances. In three patients with flow-volume loops suggestive of variable extrathoracic upper airway obstruction, measurements of alveolar pressure and airway resistance made it clear that two of the patients had upper airway obstruction, whereas the other was exerting an inadequate effort. We conclude that this noninvasive technique provides valid estimates of alveolar pressure and airway resistance continuously throughout both phases of the respiratory cycle over a wide range of volumes and flow rates. It may prove to be useful in the assessment of effort and airway obstruction in patients with a variety of pulmonary conditions.     

Inspiratory flow limitation in children with bronchopulmonary dysplasia

The objective of this study was to compare pulmonary function tests of children with bronchopulmonary dysplasia (BPD) and asthma, and to evaluate children with BPD for evidence of upper airway obstruction. This is a case-control retrospective study of pulmonary function tests (PFTs) of 11 children with BPD between 5 and 8 years of age who were followed by pediatric pulmonologists, and of 32 age- and height-matched children with asthma. The median forced vital capacity (FVC), forced expiratory volume in one second (FEV₁), and peak expiratory flow (PEF) were significantly lower in the BPD group (0.86 L, 0.79 L, 120 L/min) than in the asthmatic group (1.34 L, 1.21 L, 155 L/min; P = 0.002, P = 0.007, P = 0.004, respectively). Both groups were equally hyperinflated (median thoracic gas volume 155% of predicted values in the BPD compared to 152% predicted in the asthma group; P = 0.67), and both groups showed decreases in air-trapping after a bronchodilator. The ratios of forced expiratory flow at 50% of the FVC to forced inspiratory flow at 50% of the FVC (FEF_50%/FIF_50%) and FEV₁ to PEF (FEV₁/PEF) were used to assess upper airway obstruction and were higher in children with BPD than asthma (P = 0.0001 and P = 0.035, respectively). We conclude that pulmonary function of children with BPD who are still symptomatic after 5 years of age is different from age-matched children with asthma, and the children with BPD demonstrate significant inspiratory flow limitations. Pediatr Pulmonol. 1998;26:167–172. © 1998 Wiley-Liss, Inc.     

Pulmonary function in singers and wind-instrument players

Previous studies suggest that pulmonary function of singers and wind-instrument players may be better than normal control subjects due to breath-control training; however, prior studies were poorly controlled or limited in scope. In the present study, we compare 34 singers and 48 wind instrumentalists with a control group of 31 string or percussion instrumentalists using a pulmonary questionnaire, measurements of inspiratory and expiratory pressures, and spirometry. We found no significant difference between groups in maximum voluntary ventilation, forced expiratory volume in one second (FEV1), forced vital capacity (FVC), mean forced expiratory flow during the middle half of the FVC, the FEV1/FVC, peak expiratory pressure, or peak inspiratory pressure, independently or when corrected for age, sex, height, weight, years performing, smoking, presence or absence of cough, or sputum production. Smoking correlated negatively with measurements of pulmonary function in all groups. There was evidence of a heightened awareness of health among singers, who exercised more and smoked less than their colleagues. The differences in health habits may account in part for the myth of improved pulmonary volumes among singers.     

Ipratropium bromide protects against bronchoconstriction during bronchoscopy

Pulmonary function is reportedly impaired by fiberoptic bronchoscopy. We investigated the effect of two anticholinergic agents, intramuscular atropine and inhaled ipratropium bromide, on bronchoconstriction in 29 patients who were undergoing diagnostic bronchoscopy. The patients were divided into three groups; the first received 0.5 mg of atropine intramuscularly; the second took four puffs of 0.02 mg ipratropium bromide aerosolized by a metered-dose inhaler, and the third inhaled four puffs of a placebo. Fifteen minutes later a standardized topical anesthetic, lidocaine, was administered, and a bronchoscopic examination was performed. Pulmonary function was measured before and 15 minutes after each step. Pulmonary function was not affected by the treatment with anticholinergics or the placebo. In the placebo and the atropine groups, the topical anesthesia produced significant reductions in forced expiratory volume in 1 second (FEV,) and peak expiratory flow rate (PEFR); further reductions in these values were observed after bronchoscopy. In the group treated with ipratropium bromide there were no significant changes in FEV, and PEFR after topical anesthesia. Bronchoscopy induced significant reductions in FEV₁ and PEFR, but the changes were significantly smaller than those seen in the placebo and atropine groups. The results suggest that the deleterious effect of bronchoscopy on pulmonary function is due to topical lidocaine anesthesia and to the bronchoscopic examination itself. Inhaled ipratropium bromide protects against these deleterious effects, whereas intramuscular atropine does not.Offprint request to: H. Aizawa