Effect of theophylline on gastroesophageal reflux in normal adults

In a randomized, double-blind manner, 15 normal adults were given a single oral loading dose of anhydrous theophylline (6.5 ± 0.9 mg/kg) and nine normal adults were given placebo. All subjects were tested for serum theophylline levels, acid reflux (using intraesophageal pH probe), and lower esophageal sphincter pressure (LESP) at 1.5, 4, and 8 hr after treatment. Of subjects with negative baseline acid reflux tests, eight of 13 (61.5%) given theophylline developed positive acid reflux tests compared with none of eight subjects given placebo. One of nine (11%) placebo subjects reported heartburn compared with 11 of 15 (73%) subjects given theophylline. The maximum mean percent change in LESP from baseline was +5.62 ± 28.8% in the placebo group and ?25.01 ± 23.7% in the theophylline group (p = 0.01) at 4 hr after treatment. While only two of nine (22%) adults given placebo had at least a 14% reduction in LESP following treatment, all of the 15 subjects sustained a minimum of 14% relaxation in LESP. This study confirms that oral theophylline at therapeutic serum levels inhibits LESP and induces gastroesophageal reflux (GER) measured by acid reflux tests in most normal adults.     

儿童支气管哮喘并发胃食管反流血浆MTL和血清GAS的变化及其临床意义

目的:探讨血浆胃动素(MTL)和血清胃泌素(GAS)在儿童支气管哮喘中的水平变化,以阐明胃肠激素与支气管哮喘患儿胃肠功能的关系.方法:应用放射免疫分析(RIA)检测98例哮喘患儿MTL和GAS的水平,其中76例患儿通过平卧或抬高床脚进行吞钡X线检查,并对喘息发作的次数、年龄、严重复发性哮喘,结合伴有反胃烧心等食管炎症状的患儿做好详细的统计学处理.结果:哮喘患儿无男女性别差异.哮喘有症状和钡餐阳性者与对照组比较P＜0.001,哮喘无症状组与对照组及哮喘有症状组与无症状组比较也有显著性差异.哮喘有症状组血浆MTL和血清GAS水平明显低于对照组和哮喘无症状组,组间比较均有显著性差异(P＜0.001).结论:经观察发现哮喘反复发作可引起血浆MTL和血清GAS水平的严重降低,支气管哮喘伴发胃食管反流(GER)与哮喘反复发作引起血MTL和GAS水平降低有密切的相关性,胃肠激素水平降低是哮喘引发GER的关键所在,而GER又可触发和加剧喘息的发作.     

Gastroesophageal reflux in asthmatic patients: an incidence study and clinical correlation

The prevalence of gastroesophageal reflux (GER) in asthmatic patients is elevated, but the exact frequency remains unknown. The relationship between GER and asthma has not been investigated in Mexico. The objective of this study is to know the frequency of GER in Mexican asthmatic patients and the possible relationship with the severity of asthma. Fifty patients with adult-onset asthma were studied. AII of them fulfill the diagnostic criteria of the National Institutes of Health, U.S. The evaluation included a symptoms questionnaire, spirometry, esophageal manometry, 24-h esophageal pH-recording, and an upper gastrointestinal endoscopy. Twenty-three patients had mild asthma (46%), 16 moderate (32%) and 11 had severe asthma (22%). Twenty-seven (54%) reported heartburn and regurgitation at least twice a week. The esophageal pH-recording showed pathologic GER in 37 subjects (74%) and endoscopic esophagitis was found in 7 cases (14%). The pH-recording showed pathologic GER in 13 patients with mild asthma (57%), in 13 with moderate asthma (81%) and in all patients with severe asthma (100%). The frequency of GER in Mexican asthmatic patients is high and increases proportionately with the severity of asthma. This factor must be considered in the integral evaluation of these patients.     

Effects of proton pump inhibitor on airway hyperresponsiveness in asthmatics with gastroesophageal reflux]

BACKGROUND: Previous data suggest the high incidence of gastroesophageal reflux (GER) in asthmatics, although the relationship between GER and the respiratory condition in asthmatics remain unclear. We investigated the incidence of GER in asthmatics and the association between the effects of proton-pump inhibitor (PPI) on respiratory functions and esophageal pH in asthmatics with GER. METHODS: Two hundreds ninety outpatients who attended our unit with asthma received GER symptoms questionnaire used at Mayo Clinic. Twenty three of them who answered to have any GER symptom were treated with PPI (lansoprazole 30 mg/day) for eight weeks, and investigated changes in the GER symptoms and peak expiratory flow rates (PEFR) before and after treatment. Furthermore, in six of twenty three, airway hyperresponsiveness to methacholine and esophageal pH monitor for 24 hours were measured in order to evaluate the association between esophageal pH and the effect of PPI on GER during the test. Furthermore, the serum level of theophylline was analyzed for assessment of the PPI effect on theophylline metabolism. RESULTS: 150 of 290 asthmatics had answered to have any GER symptom including cough. Most of GER symptoms had improved except for cough after treatment with PPI. The airway hyperresponsiveness significantly improved after treatment with PPI (n=6, p<0.03), although PEF and FEV1 were not significantly changed. CONCLUSION: These results suggest that PPI may be an effective drug for asthmatics with GER through suppression of airway hyperresponsiveness.     

Silent gastroesophageal reflux in patients with bronchial asthma

Gastroesophageal reflux (GER) is a common occurrence in patients with asthma. We performed a prospective study to detect GER in patients with asthma using pH monitoring. Twenty consecutive patients (mean age 48 +/- 14 yr, range 23-70; 13 men) with asthma of unexplained etiology were evaluated. Esophageal and gastric pH were studied both while introducing and pulling out pH probe. Upper GI endoscopy was done in all the patients before doing pH monitoring. Esophageal pH was recorded at 25 cm, 30 cm and 35 cm from the incisors. Mean esophageal pH values while introducing pH probe were 2.9 +/- 1.08 (0-5.1), 2.5 +/- 1.2 (0-5) and 1.6 +/- 1.5 (0-4.6) at 25 cm, 30 cm and 35 cm from incisors respectively. The gastric pH was 0.5 +/- 0.4 (0-2). While pulling out pH probe, pH values were 1.5 +/- 1.4 (0-4.7), 2.4 +/- 1.5 (0-5.1) and 2.9 +/- 1.4 (0-5.4) at 35 cm, 30 cm, and 25 cm from incisors respectively. Of 20 patients, 19 had pH of 4 or lower at 25 cm, 30 cm and 35 cm from incisors. The mean pH value was lower at 35 cm than at 30 cm and 25 cm (1.6 +/- 1.5 vs 2.5 +/- 1.2 and 2.9 +/- 1.08, p < 0.04). In conclusion majority of adults with asthma have silent GER as detected on pH monitoring.     

Somatostatin effects on lower esophageal sphincter function.

The effect of somatostatin (GH-RIH) infusion (2 microgram/min) on lower esophageal sphincter pressure (LESP) responses to various stimuli was evaluated in adult male baboons. GH-RIH infusion did not affect basal LESP, but did cause a significant suppression of mean immunoreactive insulin (IRI) to 5.8% of basal values (P less than 0.05). Pentagastrin IV caused dose-related increases in LESP that were unaffected by GH-RIH. Abdominal compression caused a threefold rise in LESP (P less than 0.005) both without and with GH-RIH. However, atropine (20 microgram/kg iv bolus) completely blocked this cholinergic LES pressure response. Intragastric alkali as well as intragastric glycine caused significant increases in LESP (P less than 0.05). These LESP responses to alkali and to glycine were totally abolished by GH-RIH. In conclusion, GH-RIH infusion in the baboon does not affect basal LESP, LES smooth muscle response to exogenous stimulation, nor a cholinergically mediated LES response. GH-RIH does inhibit the response of LESP both to intragastric alkali and to glycine by the apparent suppression of a hormonally mediated mechanism.     

Serum interleukin – 4 and tumor necrosis factor alpha concentrations in children with primary acid gastroesophageal reflux and acid gastroesophageal reflux secondary to cow's milk allergy

AimThe possible role of serum interleukin 4 (IL-4) and tumor necrosis factor alpha (TNF- α) in pathogenesis of the reflux symptoms in children with primary acid gastroesophageal reflux (GER) and acid GER secondary to cow's milk allergy (CMA).Material and methodsOut of 264 children, 76 (28.8%) patients with primary GER and 62 (23.5%) patients with GER secondary to CMA (pH – monitoring) serum IL-4 and TNF- α concentrations were assessed before treatment, 1 and 2 years after the initiation of the periodically administered pharmacotherapy.ResultsChildren with primary GER had mean IL-4 concentrations 0.17 ± 0.06 pg/ml before treatment, 0.08 ± 0.07 pg/ ml after 1-year and 0.07 ± 0.06 pg/ml after 2-years of treatment. The mean IL-4 concentrations were 1.07 ± 0.24, 0.5 ± 0.22 and 0.44 ± 0.19 pg/ml respectively in children with GER secondary to CMA.The mean serum TNF- α concentrations was 3.62 ± 1.30 pg/ml before treatment, 2.16 ± 1,35 pg/ ml after 1 year and 1.65 ± 1.16 pg/ml after 2 years of treatment in children with primary GER. In group with GER secondary to CMA mean serum TNF- α concentrations were 4.95 ± 1.88, 2.53 ± 0.80 and 2.02 ± 0.78 pg/ml respectively. Statistical analysis of the concentration of both cytokines showed their differentiation between them and in the study groups.ConclusionsThe highest mean serum IL-4 and TNF-α concentrations were observed in children with GER secondary to CMA and in children in control group (with cow's milk allergy and/or other food allergy diagnosed – CMA/FA) before the treatment administration.     

Effect of theophylline on gastroesophageal reflux in patients with asthma

A possible role of methylxanthines in the high incidence of gastroesophageal reflux (GER) in patients with asthma has been suggested. Therefore, we used a randomized, double-blind, crossover design to compare the effects of a 1-week conventional theophylline treatment and a 1-week placebo treatment in 16 adult patients with asthma. No oral or parenteral glucocorticoids were administered, but seven patients were taking inhaled corticoids. All patients needed inhaled adrenergic drugs. At the end of each period of theophylline or placebo treatment, the patients were carefully questioned with respect to respiratory and digestive symptoms, forced expiratory flows were measured, and GER was assessed by prolonged nocturnal intraesophageal pH monitoring. Peak expiratory flow was measured three times a day throughout the study. No significant increase in GER was found with theophylline compared to placebo, and forced expiratory flows improved with theophylline (p less than 0.05 for FEV1 and p less than 0.01 for peak expiratory flow rate). There was no correlation between GER, the duration of asthma, and forced expiratory flows. Thus, our study failed to demonstrate any adverse effect of a slow-release theophylline preparation on GER in patients with asthma. These results further suggest that the presence of GER is not a contraindication to the use of a slow-release theophylline in subjects with asthma.     

The effect of surgically created gastroesophageal reflux on intrapleural pressures in dogs

The causal relationship between gastroesophageal reflux (GER) and respiratory disorders is not well understood. Previous experimental studies that investigated this relationship were performed in anesthetized animals and used artificial acidification of esophagus for simulation of GER. In this study, we investigated the impact of GER on intrapleural pressures (IPP) in conscious, unanesthetized dogs. After the induction of appropriate anesthesia, 5 purpose-bred mongrel dogs underwent reflux-creating surgery (partial cardiomyectomy). The presence of GER was confirmed by determining the reflux index (RI) and the duration of longest reflux episode (DLRE) after 24-h intraesophageal pH-metry. IP was monitored before and after cardiomyectomy using a subcutaneously placed telemetric implant with its pressure-sensor catheter tip inserted into the pleural space. Partial cardiomyectomy resulted in a significant increase in RI from a preoperative mean value of 0.38 +/- 0.21 to 7.52 +/- 2.56%, and DLRE from 1.22 +/- 1.12 to 36.80 +/- 12.71 min, as recorded by the proximal sensor of the pH probe. A similar trend was observed at the distal sensor. After cardiomyectomy, the negative inspiratory IPP significantly increased from 17.2 +/- 7.9 to 28.4 +/- 9.7 mm Hg. A similar effect was observed in the negative expiratory IPP. The negative inspiratory IPP had a significant correlation with both RI (R = 0.932) and DLRE (R = 0.899). Cardiomyectomy causes GER, the severity of which correlates with negative inspiratory IPP in a dog model. The suggested model allows for the investigation of the pathologic association of GER with respiratory disorders in conscious animals.     

A fast, simple, and inexpensive method to collect exhaled breath condensate for pH determination.

BACKGROUND: Exhaled breath condensate (EBC) analysis is a noninvasive method for assessing lower airway inflammation. Various methods of collecting EBC have been described. However, they are often time-consuming or involve expensive equipment. OBJECTIVE: To evaluate the efficiency and repeatability of a simple, fast, and inexpensive method of EBC collection for pH determination. METHODS: Twenty-four mild asthmatic patients, 18 moderate-to-severe asthmatic patients, and 26 controls were asked to slowly exhale for 45 seconds into a -80 degrees C cooled metal cylinder covered with protective rubber and attached to a piece of tubing. The EBC was collected using a syringe's plunger. The groups were compared regarding EBC pH. Reproducibility tests were also performed. Induced sputum samples were obtained for inflammatory cell counts. RESULTS: We obtained approximately 50 microL of EBC for pH determination. Mild asthmatic patients had lower mean +/- SD pH values than controls (5.97 +/- 0.48 vs 6.36 +/- 0.34; P = .008), and corticosteroid-treated, moderate-to-severe asthmatic patients had mean +/- SD pH values similar to controls (6.23 +/- 0.38; P > .05). Mean +/- SD sputum eosinophil percentages were higher in both asthmatic groups than in controls (3.42% +/- 5.37% and 4.14% +/- 4.98% vs 0.04% +/- 0.12%; P < .001) and were not correlated with pH values in all groups. The mean intraday coefficient of variation for the method was 4.8% (range, 0.9%-8.8%). No correlation was found in all groups between sputum neutrophils and pH. CONCLUSIONS: We developed a useful device for collecting EBC for pH evaluation that could provide an alternative to other methods when pH is the main variable evaluated.     

Gastroesophageal reflux and pulmonary disease

Gastroesophageal reflux (GER) is a functional entity which is defined as "the involuntary reflux of the gastric contents in the oesophagus, without vomiting and without the involvement of either the gastric, abdominal or diaphragmatic muscles". It is therefore a question of a syndrome which is independent of the anatomical abnormalities in the cardio-tuberositic region (i.e. hiatal hernia). It may also show itself through digestive symptoms, thoracic pains, ENT symptoms and breathing complications. The presence of the latter has been clearly established in certain circumstances: --in infants, GER can cause obstructive apneas, which are responsible for sudden inexplicable deaths (SID): GER and SID have very similar epidemiological characteristics; polygraphic recordings showed that a reflux may immediately precede the onset of obstructive apnea; the instillation of 0.1 N hydrochloric acid in the oesophagus of children with GER causes an apnea. Medical or surgical treatment of the reflux prevents the recurrence of these accidents; --in adults, and older children, GER is responsible for coughs, recurring bronchopneumopathies and asthma; long-term recordings of the oesophageal pH have proved that there is a time-relationship between the two events. Scintigraphic studies have shown the pulmonary contamination by a radioactive isotope placed in the stomach the previous evening. GER has been equally suspected for conditions such as lung abscess, bronchiectasis and hemoptysis, but here it is more difficult to prove. With certain pulmonary fibroses, histological lesions have been compared with those observed during inhalation bronchopneumopathies, but it is difficult to establish a link with a reflux; --functional respiratory studies have not produced a specific functional entity for patients with GER; --careful medical treatment or surgical correction of GER lead to the sedation of respiratory symptoms (RS) in the majority of cases; --the association frequency of a GER and of RS is difficult to establish because of the diversity of the means of diagnosis employed in the past and also because of the heterogeneity of the studied populations, but the frequency is nevertheless high, indeed significantly higher than the prevalence of GER in the general population. The mechanisms which link GER and RS are not well known: first of all, there is the failure of normal antireflux mechanisms and also certain hormonal, alimentary (coffee, alcohol, tobacco, etc.) and therapeutic (theophylline, betamimetics) factors, which facilitate the reflux.(ABSTRACT TRUNCATED AT 400 WORDS)     

酸反流指数在儿童病理性胃食管反流诊断中的价值附12年4109例食管pH值监测结果分析

目的了解酸反流指数（RI）在儿童病理性胃食管反流（GER）诊断中的价值,探讨儿童病理性GER的诊断标准。方法对在浙江大学医学院附属儿童医院进行食管pH值监测的数据进行归纳和整理,并除外复查和少数未能完成监测的数据。根据Boix-Ochoa标准（金标准）综合评分〉11.99诊断病理性GER,对RI进行受试者工作特征（ROC）曲线分析,获得最佳诊断界点值（cutoff value）。通过McNemar卡方检验和Kappa检验,评价各种以RI为基准的病理性GER诊断标准所得结果的差异及其吻合度,并进一步评价各种标准诊断GER的敏感度、特异度等指标的差异。结果1994年9月至2006年5月有5000例患儿进行食管pH值监测,有效数据者4109例进入分析,其中男性2692例,女性1417例。新生儿476例,-1岁1553例,-3岁658例,-7岁837例,-12岁513例,-16岁72例。病种构成有13类,依次为：支气管哮喘366例,支气管炎468例,支气管肺炎385例,迁延性肺炎143例,慢性咳嗽184例,慢性咽炎29例,新生儿呼吸暂停102例,新生儿呕吐283例,新生儿肺炎105例,呕吐或伴腹痛1817例,食管裂孔疝140例,非心源性胸痛55例,营养不良32例。ROC曲线分析显示RI最佳诊断界点为2.9,其敏感度为90.4%,特异度为95.6%（假阳性率〈5.0%）。ROC曲线下面积为0.981（95%CI：0.977-0.984）,sx-为0.002,用于诊断病理性GER有统计学意义（P=0.000）。分别以RI≥4.0%（RI 4.0标准）、RI≥2.9%（RI 2.9标准）为病理性GER诊断标准,以手术确诊的140例食管裂孔疝患儿进行分析,与Boix-Ochoa标准进行比较。RI 2.9标准的总体吻合度高于RI 4.0标准（κ系数分别为0.892、0.715,P均=0.000）。除了特异度,RI 2.9标准诊断病理性GER的敏感度、准确性和阴性预测值均明显高于RI 4.0标准,而阳性预测值两者相近。结论RI 2.9标准诊断病理性GER有显著意义,与RI 4.0标准相比,有助于提高儿童病理性GER诊断的敏感度和准确性。     

Serum gastrin concentrations in children with primary gastroesophageal reflux and gastroesophageal reflux secondary to cow's milk allergy

PurposeThe assessment of the serum gastrin concentrations and the role of enterohormone in children with primary acid gastroesophageal reflux (GER) and GER secondary to cow's milk allergy (CMA).Materials/Methods138 children were diagnosed with pathological acid GER on the basis of pH-metric examination. 76 (28.8%) patients had primary GER and 62 (23.5%) patients had GER secondary to CMA.Serum gastrin concentration (fasting and postprandial) was assessed before treatment and 1 and 2 years after initiation of the therapy.ResultsThe children with primary GER had the fasting gastrin concentration 69.46 ± 11.87 μU/ml before treatment, 77.86 ± 26.35 μU/ml after 1 year and 83.78 ± 25.21 μU/ml after 2 years of treatment. The children with GER secondary to CMA had gastrin concentrations 89.61 ± 26.75, 73.17 ± 19.49 and 73.90 ± 20.31 μU/ml respectively. The mean postprandial gastrin concentration after treatment was higher than before treatment in children with both primary and secondary GER. The primary GER group had postprandial gastrin concentration 96.07 ± 33.51 μU/ml before treatment and 116.06 ± 33.95 μU/ml and 118.48 ± 33.96 μU/ml after 1st and 2nd year of therapy respectively. The secondary GER group had postprandial gastrin concentration 85.33 ± 14.12 μU/ml before treatment and 106.55 ± 24.51 μU/ml and 110.36 ± 24.67 μU/ml after 1st and 2nd year of therapy respectively.ConclusionsThe mean fasting serum gastrin concentrations in patients with primary and secondary GER were similar and mean postprandial concentrations were higher than fasting concentrations in both study groups.     

Acid-base equilibrium in exhaled breath condensate of allergic asthmatic children

BACKGROUND: The dysregulation of airway pH control may have a role in asthma pathophysiology. The measurement of exhaled breath condensate (EBC) pH and ammonia levels may be used as a noninvasive method to study acid-base status in the airway of asthmatics. METHODS: Exhaled breath condensate from 29 allergic stable asthmatic children and 13 healthy controls was collected by cooling exhaled air during tidal breathing. Ammonia was measured by high-performance liquid chromatography with fluorescence detection. pH was measured after deaeration of EBC samples by bubbling with argon. The children also underwent FENO measurement. RESULTS: Both pH and ammonia values in EBC were significantly lower in the asthmatics than in the control group [pH: ICS-treated (median and interquartile range) 7.70 (7.62-7.74), steroid-naive 7.53 (7.41-7.68), controls 7.85 (7.80-7.90), P <0.01 and P <0.001, respectively; ammonia: ICS-treated 476.17 microM (282.50-594.80), steroid-naive 253.24 microM (173.43-416.08), controls 788.30 microM (587.29-1310.39), P < 0.05 and P <0.001, respectively]. Both pH and ammonia values were higher in ICS-treated than in steroid-naive asthmatic children. There was a significant correlation between EBC pH and ammonia concentrations. CONCLUSIONS: These data show that EBC pH values of stable asthmatic children are lower compared with those of healthy controls and positively correlated with ammonia concentrations, supporting the hypothesis that airway acidification may have a role in the pathobiology of allergic asthma.     

The efficacy of the upright position on gastro-esophageal reflux and reflux-related respiratory symptoms in infants with chronic respiratory symptoms

Purpose

Gastro-esophageal reflux (GER), particularly non-acid reflux, is common in infants and is a known cause of chronic respiratory symptoms in infancy. Recent guidelines recommended empirical acid suppression therapy and the head-up position in patients with suspected GER. However, the efficacy of the upright position in relieving GER and reflux-related respiratory symptoms in infants is unclear. We conducted this study to investigate the efficacy of the upright position on GER and reflux-related respiratory symptoms in infants with chronic respiratory symptoms.

Methods

Thirty-two infants (21 male; median age, 5 months; range, 0 to 19 months) with unexplained chronic respiratory symptoms underwent multi-channel intraluminal esophageal impedance and pH monitoring. We retrospectively compared the frequencies of GER and reflux-related symptoms according to body position.

Results

A mean of 3.30 episodes of reflux per hour was detected. Overall, refluxes were more frequent during the postprandial period than the emptying period (3.77 vs. 2.79 episodes/hour, respectively; P=0.01). Although there was no significant difference in the total refluxes per hour between the upright and recumbent positions (6.12 vs. 3.77 episodes, P=0.10), reflux-related respiratory symptoms per reflux were significantly fewer in infants kept in an upright position than in a recumbent position during the postprandial period (3.07% vs. 14.75%, P=0.016). Non-acid reflux was the predominant type of reflux in infants, regardless of body position or meal time.

Conclusions

The upright position may reduce reflux-related respiratory symptoms, rather than reflux frequency. Thus, it may be a useful non-pharmacological treatment for infantile GER disease resistant to acid suppressants.     

Gastroesophageal reflux disease

Physiological gastroesophageal reflux (GER) is the passage of gastric contents into the esophagus and occurs up 2/3 of normal infants; and, it resolves spontaneously around 9-12 months of age. When GER causes symptoms or complications is considered gastroesophageal reflux disease (GERD) and it is associated to growth impairment, anemia, apnea, wheezing or other chronic respiratory symptoms, asthma, recurrent pneumonia or sleeping problems. Diagnosis of GERD implies studies as upper gastrointestinal series, upper endoscopy and 24 h esophageal pH monitoring; special cases may require motility and nuclear medicine studies. GER may be successfully treated with prone elevated position (30-45 degrees), shortening the feeding intervals to 3 h and anti-GER high-viscosity formulas. The regular use of prokinetic drugs is not recommended. The efficacy of proton pump inhibitors and H2 histamine receptor antagonists in the treatment of GERD has been demonstrated in children by diminishing de acid secretion of parietal cells, lowering the gastric contents and decreasing its ability to cause peptic-acid damage to the esophagus or to the respiratory tract. Surgical treatment is indicated in chronic recurrent GERD, usually in children 5 years or older with dependent proton pump inhibitor erosive esophagitis, chronic respiratory disease and in risk-selected cases.     

Capillary pH and blood gas determinations in asthmatic children.

Earlobe capillary pH and blood gases in asthmatic children were compared to arterial values. Hyperemia of the earlobe was produced by applying thurfyl nicotinate (Trafuril). Approximately 15 min later capillary blood was obtained simultaneously with a radial arterial sample. Earlobe capillary PO2, PO2, and pH correlated well with arterial values. This technique is simple, safe, and appears to be a satisfactory substitute for arterial blood in normotensive asthmatic children.     

Respiratory response to intraesophageal acid infusion in asthmatic children during sleep

Nocturnal asthma has been associated with nighttime gastroesophageal reflux (GER). To establish whether the presence of acid in the lower esophagus causes bronchoconstriction, nine children with nocturnal asthma and GER underwent intraesophageal acid-infusion challenges during sleep. The patients were divided into two groups on the basis of presence or absence of a positive Bernstein test for esophagitis. The test was considered positive if acid infusion produced symptoms of heartburn. On two occasions, at approximately midnight and 4 to 5 a.m., 30 ml of normal saline was infused over 15 min into the distal esophagus followed by a similar infusion of 0.1N HCl. Respiration was continuously monitored by inductance plethysmography along with clinical evaluation. The saline and midnight acid infusions had no effect in either patient group; however, with the 4 to 5 a.m. acid infusion, all the patients with a positive Bernstein test developed significant changes in their respiratory pattern indicative of bronchoconstriction as well as overt clinical wheezing. In the patients with a negative Bernstein test, the 4 to 5 a.m. acid infusion had no effect. It is concluded that during sleep the presence of acid in the lower esophagus can trigger bronchoconstriction in asthmatic children with a positive Bernstein test and that these children appear to be more susceptible to the bronchoconstrictive effects of intraesophageal acid at 4 to 5 a.m. than at midnight.     

猫下食管括约肌对A型肉毒毒素的反应

目的： 应用A型肉毒毒素（BTA）局部注射于猫下食管括约肌（LES）,通过LES测压、局部乙酰胆碱（Ach）含量和乙酰胆碱酯酶（AchE）活性测定以及光镜、透射电镜观察,研究BTA对LES的作用机制,为临床BTA治疗贲门失弛缓症提供科学依据。方法：在胃镜下对BTA组（10只猫）LES分4点注射BTA,对照组（10只猫）注射生理盐水,分别于注射前、注射后1周测定LES的压力。处死猫后取LES,测定LES中Ach的含量和AchE活性;将LES作超薄切片,按Karnovsky-Roots法做AchE染色,在光镜和电镜下观察AchE阳性神经末梢和Ach囊泡的超微结构。结果：（1）BTA组LES压力（9.93±1.06） mmHg显著低于对照组（28.17±3.55) mmHg,P<0.01。（2）BTA组LES Ach含量(75.48±4.67) mg/g组织和AchE活性(38.20±2.17) 103 U/g组织均显著低于对照组,分别为(93.03±4.65) mg/g组织、(69.88±6.73) 103 U/g组织,均P<0.01。（3）在光镜下发现,运动终板色泽变淡,数目减少;在电镜下发现,神经末梢内含Ach的囊泡明显减少,末梢内AchE阳性反应物也明显减少。结论：猫LES局部注射BTA后,可引起LES压力明显下降,其机制可能为BTA破坏局部胆碱能神经末梢运动终板中的囊泡,导致局部Ach含量和AchE活性明显降低。     

The significance of intraepithelial eosinophils in the histologic diagnosis of gastroesophageal reflux

Detection of intraepithelial eosinophils in esophageal mucosal biopsies has been suggested as histologic evidence of symptomatic gastroesophageal reflux (GER) disease in both children and adults. Previous studies have primarily examined symptomatic persons, and only one study included a comparison with normal controls. In the present study, the authors examined esophageal mucosal biopsies obtained by the hydraulic suction technic for the presence of intraepithelial eosinophils from 73 adult patients with subjective and objective evidence of GER disease and 12 asymptomatic adult volunteers in whom a series of esophageal function tests were normal. Intraepithelial eosinophils were identified in 23 (31.5%) of adult patients and in 4 (33.3%) of the asymptomatic volunteers. No clinical aspects in the GER patients correlated with the presence of eosinophils. By crude quantitation, rare eosinophils added little to more conventional assessment of histologic esophagitis and were present in one-third of normal subjects. The authors conclude that rare eosinophils in esophageal biopsies may not be a reliable criterion for the histologic assessment of GER disease.