Usefulness of the transcutaneous Po2 monitor during exercise testing in adults.

The usefulness of the transcutaneous Po2 monitor for monitoring during stress testing was evaluated. Seventy-five simultaneous recordings of arterial and transcutaneous Po2 were made on 11 patients with chronic obstructive pulmonary disease while they were undergoing treadmill exercise testing. All arterial blood samples were drawn from an indwelling brachial arterial line and analyzed in duplicate. The range of arterial Po2 measured was 50 to 145 mm Hg. The correlation coefficient (relationship between arterial and transcutaneous Po2) was .96 and the slope of the best fit line was 1.047 (Y = 1.047 x -7.2). The transcutaneous Po2 was an average of 5.99 +/- 4.76 mm Hg below the arterial Po2 in the entire group. The mean difference in transcutaneous and arterial Po2 was greater at low Po2 level, than at high levels. We found the electrode easy to maintain and calibrate, with a low frequency of malfunction. This instrument provides a safe, simple, and reliable noninvasive method for recording serial changes in Po2 during exercise testing.

Cerebral air embolism and cerebral edema: one regimen of treatment.

A case of cerebral air embolism responding immediately to compression to 6 atm is described. The patient, however, developed apparent cerebral edema while being decompressed. Subsequent recompression on oxygen was carried out twice daily at 60 ft (18 m, 2.8 ATA) for 60 min until the patient's symptoms had nearly cleared. While a number of other medications known to affect intracranial pressure were used, objective clinical improvement was noted only after hyperbaric oxygen. A question is raised of whether there is an association between the development of cerebral edema and the administration of intravenous 5% glucose in water.

Interstital lung disease due to contamination of forced air systems.

Eight patients had hypersensitivity pneumonitis due to contaminated home or office forced-air heating or air-conditioning systems. We studied their clinical and laboratory features, and the results indicated that this disease may occur as an acute or insidious form differing in type and intensity of respiratory and systemic symptoms. Thermophilic actinomycetes contaminatinf the forced air systems were identified as the sensitizing agents in most cases. Precipitating antibodies to the organisms could be shown in the serums of the patients and the antigen identified by immunofluorescent studies in the three lung biopsies examined by this method. Inhalation challenge studies with the cultured organism or other materials obtained from the forced air systems reproduced the clinical syndrome in the four patients tested. Avoidance of the contaminated system, and the use of corticosteroids in more severe cases,seems to be appropriate therapy for patients with this disease.

Hypersensitivity studies in popple (Aspen tree) peelers.

In the course of investigation of the relationship between hypersensitivity pneumonitis and the wood industry 45 popple peelers were studied. Four roentgenograms consistent with diffuse lung disease were found. All cases were in examinees who were also dairy farmers. Questionnaires revealed no instance of clinical symptoms of hypersensitivity pneumonitis. Gel immunodiffusion studies were positive to various antigens in eight cases, but no correlation could be made with pulmonary function or chest roentgenogram abnormalities in relation to occupation. Cultures of the wood and the surrounding environment yielded thermophilic fungi as well as other known antigenic material. It is concluded that the occupation of popple peeling does not represent an increased risk of development of hypersensitivity pneumonitis.