Improving compliance with nasal CPAP and vigilance in older adults with OAHS.

The present study examined the efficacy of a cognitive-behavioral intervention at improving compliance with CPAP and vigilance in older adults with obstructive sleep apnea/hypopnea syndrome (OSAHS). Participants included 12 subjects who were randomized into one of two groups controlling for age, education, disease severity, and vigilance. The experimental group received two 45-min sessions designed to educate subjects on the consequences of OSAHS and the efficacy of CPAP. The control group received the same extent of therapist contact but did not receive information on OSAHS or CPAP. All subjects were administered a test of vigilance both before and after the study. Compliance data were collected using CPAP devices with internal microprocessors at were read at 1, 4, and 12 weeks after treatment initiation. The results showed that the experimental condition did not enhance compliance after 1 week of treatment but did so by the 12-week follow-up. Subjects in the experimental condition had a run time of 3.2-h per night longer than did those in the control group. Those using CPAP more regularly at 12 weeks also showed greater improvement on vigilance at follow-up. Performance on vigilance testing before the introduction of CPAP was predictive of CPAP use at 12 weeks. In conclusion, a modest cognitive-behavioral intervention may substantially increase CPAP use and vigilance in older adults.

Bronchial provocation tests before and after cessation of smoking.

We studied the effect of smoking cessation on airway reactivity. We recruited cigarette smokers who were attempting to stop smoking. Entry criteria required each subject to be smoking at least 10 cigarettes each day and report a chronic cough. Exclusion criteria included significant airflow obstruction or the presence of any medical condition contraindicating challenge testing. Carbachol challenge was performed to assess airway reactivity according to a standardized method. Baseline measurements of forced expiratory volume in 1 s (FEV1), specific airway conductance (SGaw) and the provocative dose of carbachol causing a 35% reduction in SGaw (PD35), and a 20% reduction in FEV1 (PD20) were established on entry while each subject was still smoking. Thereafter, repeat measurements were performed after 2 and 6 months of smoking cessation. Adherence to smoking cessation was checked by self-report and verified by measurement of alveolar carbon monoxide levels at each session. Of the 34 subjects who gave consent, 13 relapsed prior to the 2nd month and an additional 8 relapsed before the 6th month. Thirteen of the 34 remained abstinent throughout the 6-month study. All 13 subjects had complete resolution of their cough. The difference in reactivity on entry to that at the 2nd and 6th month was not significant. We conclude that (1) the symptom of chronic cough resolved completely after 2 months of smoking cessation, and (2) airway reactivity remained unchanged at 2 and 6 months of smoking cessation.

Inhaled metaproterenol is superior to inhaled cromolyn in protecting against cold-air-induced bronchospasm.

Eucapneic hyperventilation of cold air (EHCA) provokes bronchospasm in asthmatics. Although inhaled cromolyn powder and sympathomimetic solutions have attenuated the bronchospasm induced by EHCA, comparison of both drugs in solution has not been performed. We performed a prospective double-blind study comparing cromolyn solution, metaproterenol solution, and placebo (normal saline) given prior to EHCA. Eight asthmatics defined by a 20% reduction in forced expiratory volume in 1s (FEV1) after EHCA consented to the study. Patients were tested on 3 separate occasions at a similar time of day. Each session began with a determination of FEV1 followed by a randomized double-blind treatment. A repeat FEV1 (pre-EHCA) was performed 20 min after drug inhalation. Twelve minutes of EHCA was performed consisting of 4 min of tidal breathing, 4 min of eucapneic hyperventilation (60-70% of the predicted MVV) and a final 4 min of tidal breathing. FEV1 was performed immediately, 5 min, and 10 min after EHCA. The lowest value was defined as the post-EHCA FEV1. The pre-EHCA FEV1 was significantly larger after metaproterenol pretreatment compared to the pre-EHCA FEV1 following cromolyn (p = 0.01) and saline (p = 0.04). Metaproterenol pretreatment had a significant protective effect in comparison to placebo pretreatment (p less than 0.01). No other paired comparisons (cromolyn vs. placebo, cromolyn vs. metaproterenol) achieved statistical significance at a 0.05 level. In conclusion, metaproterenol is superior to cromolyn in protecting against cold-air-induced bronchospasm.

Hyperthyroidism protects against carbachol-induced bronchospasm.

We studied the effect of increased thyroid function on airway reactivity. Carbachol challenge was performed to assess airway reactivity according to a standardized method. Measurements of forced expiratory volume-1 second (FEV1), specific airway conductance (SGaw), the provocative dose of carbachol for a 20 percent decrease in FEV1 (PD-20) and that for a 35 percent decrease in SGaw (PD-35) were established upon entry when each subject was hyperthyroid, and subsequently, after the subjects had returned to the euthyroid state. It was concluded that hyperthyroidism reduced the severity of carbachol-induced changes in airway reactivity as measured by SGaw.

Value of chest ultrasonography versus decubitus roentgenography for thoracentesis.

Chest ultrasonography (CU) has been advocated as an effective tool for diagnosis and localization of pleural fluid. Studies to date supporting the technique have been anecdotal and nonrandomized. To determine if CU was beneficial when thoracentesis was performed by clinicians or house staff, we evaluated prospectively 205 patients presenting with pleural effusion at 2 community teaching hospitals. Decubitus roentgenograms were obtained on all patients, but CU with targeting by skin marker was performed on a randomized basis. Results were evaluated as to (1) whether the quantity of fluid obtained was sufficient for the intent of the procedure, (2) the number of needle insertions required to obtain the fluid, and (3) the incidence of complications such as pneumothorax. One hundred three effusions were evaluated by CU and 102 by roentgenography alone. The effusions in each group were stratified as small (obliteration of less than half of the hemidiaphragm on roentgenogram) or large. Small effusions were further stratified as free flowing or loculated (no layering of fluid on decubitus roentgenograms). By chi-square test, CU was significantly superior to decubitus roentgenograms alone for obtaining adequate fluid samples in small effusions (p less than 0.01). This was true regardless of whether the effusion was loculated (p less than 0.02) or free flowing (p less than 0.05). The technique had no such advantage in large effusions. We did not find that CU significantly reduced the need for multiple attempts nor incidence of complications in any group.

Differentiation of tuberculous from nontuberculous cavitary lung disease.

Tuberculous and nontuberculous cavitary lung disease is often initially misdiagnosed, delaying therapy. To identify findings which might help avoid such delays, we performed a retrospective review of all patients admitted to two community hospitals over a 6-year period for infectious cavitary disease of the upper lobe or apical segment of the lower lobe. 10 patients with tuberculosis and 16 with nontuberculous infections were identified. Delays in initiating therapy were common to both. Most signs and symptoms were nonspecific. The mean duration of symptoms was greater in tuberculosis (72 days) compared to nontuberculous infections (18 days). Putrid sputum was found only in nontuberculous infections (11/16). Roentgenographic features of fibronodular infiltration and atelectasis occurred only in tuberculosis. Air fluid levels were seen only in nontuberculous disease (10/16). Leukocytosis with immature neutrophils was found only in patients with nontuberculous cavities. We conclude that the previously described clinical, laboratory, and roentgenographic features may be useful in correctly diagnosing infectious cavitary lung disease.

The protective effect of methylprednisolone on carbachol-induced bronchospasm.

We studied the effect of acute treatment with methylprednisolone in 12 asthmatics not dependent on steroids. Carbachol challenge was performed according to a standardized method. Baseline measurements of forced expiratory volume in one second (FEV1), specific airway conductance (SGaw), the provocative dose of carbachol for a 20% decrease in FEV1 (PD20), and that for a 35% decrease in SGaw (PD35) were established. Thereafter, patients returned for retesting at 2, 4, and 6 wk. Prior to each visit, the patients received 1 of 3 treatments: placebo, low-dose (32 mg) methylprednisolone, or high-dose (128 mg) methylprednisolone given orally and distributed in a randomized double-blind fashion. Blood levels confirmed compliance in all subjects. All subjects remained stable throughout the study, with intrasubject FEV1 values agreeing within 5% at the start of each session. The pairwise differences for low-dose methylprednisolone versus placebo were significantly different for both PD20 (p = 0.0004) and PD35 (p = 0.0068). The pairwise differences for high-dose methylprednisolone versus placebo were also significantly different for PD20 (p = 0.04) and PD35 (p = 0.0034). Blocked comparisons of the 2 different methylprednisolone doses were not significantly different. We conclude that methylprednisolone has a protective effect on carbachol-induced bronchospasm, and that this effect is not dose-related at the two doses studied.

Sensitivity, specificity, and predictive values of closed pleural biopsy.

To determine the clinical value of a nonspecific pleural biopsy specimen and fluid in malignant neoplasm and tuberculosis, we retrospectively reviewed records of all patients with pleural effusions undergoing the procedure at three community hospitals over six years. Two hundred eleven patients underwent biopsies. Adequate tissue was obtained in 207. The results were compared with the ultimate clinical and pathologic outcome by follow-up for 12 to 72 months. The initial procedure was diagnostic of malignant neoplasm in 54 patients and granulomatous disease in ten. A nonspecific or normal result was found in 143 (68%). Malignant neoplasms or tuberculosis was eventually established in 30 and excluded in 101 of the 143 patients. In 12 patients, no diagnosis was made. The procedure's sensitivities were 65% (malignant neoplasm) and 90% (tuberculosis). One false-positive result occurred in a patient with nontuberculous granulomatous pleuritis. The specificity and positive predictive value were 99% and 98%, respectively. The negative predictive value was 77%. Closed pleural biopsy with simultaneous fluid analysis is a valuable diagnostic procedure in community hospital patients, but a nonspecific result does not exclude malignant disease.

Haemophilus parainfluenzae lung abscess.

To our knowledge, Haemophilus parainfluenzae lung abscess has not been described previously. Such a case is presented in the setting of diabetes mellitus. The implications of diagnosis and management are discussed.

Abnormal mucociliary transport in allergic patients with antigen-induced bronchospasm: role of slow reacting substance of anaphylaxis.

We evaluated the possible role of slow reacting substance of anaphylaxis (SRS-A) in mediating mucociliary dysfunction in allergic asthma. In 6 asymptomatic nonsmokers with ragweed asthma, we measured specific airway conductance (SGaw) and tracheal mucous velocity (TMV) before and after bronchial challenge with ragweed extract, with or without pretreatment with 0.5% and 1% FPL-55712 (SRS-A antagonist). Mean baseline TMV was 8.9 mm/min (SD, 1.1). Placebo and FPL-55712 per se had no effect on TMV. With placebo pretreatment, the doses of ragweed extract that resulted in a decrease in SGaw by more than 35% from baseline, led to an immediate decrease in TMV to 74% of baseline (p less than 0.05), returning to baseline within 2 h. With 0.5% and 1% FPL-55712 pretreatment, doses of ragweed extract that resulted in a similar decrease in SGaw led to an increase in TMV to 130% and 126% of baseline (p less than 0.05), respectively, immediately after antigen challenge and returned to baseline 2 h postchallenge. Inhalation of 1% FPL-55712 immediately after antigen challenge prevented the decrease in TMV. These results indicate that (a) SRS-A liberated during airway anaphylaxis impairs mucous transport, and (b) the antigen-induced increase in TMV after pretreatment with an SRS-A antagonist may reflect a stimulatory effect of other chemical mediators of anaphylaxis.