[Safe local anesthesia in patients with bronchial asthma]. / Osobennosti bezopasnogo mestnogo obezbolivaniia u patsientov s bronkhial'noi astmoi.

The paper presents the analysis of studies of local anesthesia in patients with bronchial asthma. It was found that the diagnosis of hypersensitivity to sodium metabisulfite in patients with bronchial asthma must be optimized for development of local anesthesia selection algorithm in outpatient dentistry.

Effect of respiratory protective devices on development of antibody and occupational asthma to an acid anhydride.

STUDY OBJECTIVES: To determine whether the use of respiratory protective equipment would reduce the incidence of occupational asthma due to exposure to hexahydrophthalic anhydride (HHPA). DESIGN: Prospective cohort study. SETTING: A facility that makes an epoxy resin product requiring HHPA for its manufacture. PARTICIPANTS: Sixty-six individuals newly hired at a facility that makes an epoxy resin product requiring HHPA for its manufacture. INTERVENTION: Employees who wished to use respiratory protective equipment could choose from three types of masks: dust mask, half-face organic vapor respirator, or full-face organic vapor respirator. MEASUREMENTS: Workers were evaluated annually for development of positive antibody to HHPA and occupational, immunologic respiratory disease, including occupational asthma. RESULTS: With use of respiratory protective equipment, the rate of developing an occupational immunologic respiratory disease was reduced from approximately 10 to 2% per year. Occupational asthma developed in only three individuals, and they were all in the higher exposure category. Statistically, one respirator was not superior to the others. CONCLUSION: Respiratory protective equipment can reduce the incidence of occupational immunologic respiratory disease, including occupational asthma, in employees exposed to HHPA.

Occupational contact urticaria caused by airborne methylhexahydrophthalic anhydride.

Acid anhydrides are low-molecular weight chemicals known to cause respiratory irritancy and allergy. Skin allergy has on rare occasions been reported. A total of 3 subjects with occupational exposure to methylhexahydrophthalic anhydride (MHHPA) and hexahydrophthalic anhydride (HHPA) from an epoxy resin system were studied to evaluate the nature of their reported skin and nose complaints (work-related anamnesis, specific IgE, contact urticaria examinations, and ambient monitoring). Using a Pharmacia CAP system with a HHPA human serum albumin conjugate, specific IgE antibody was detected in serum from 1 (33.3%) out of the 3 workers. One unsensitized worker displayed nasal pain and rhinorrhea only when loading liquid epoxy resins into the pouring-machine (2.2 mg MHHPA/m3 and 1.2 mg HHPA/m3), probably being an irritant reaction. Two workers had work-related symptoms at relatively low levels of exposure (geometric mean 32-103 microg MHHPA/m3 and 18-59 microg HHPA/m3); one complained of only rhinitis, and the other was sensitized against HHPA and displayed both rhinitis and contact urticaria (the face and neck). The worker's skin symptoms were evidently due to airborne contact, since she had not had any skin contact with liquid epoxy resin or mixtures of MHHPA and HHPA. These urticaria symptoms were confirmed by a 20-min closed patch test for MHHPA, but not by that for HHPA. The causative agent was considered to be MHHPA, although the specific IgE determination to MHHPA was not performed.

Exposure-response relationships in rhinitis and conjunctivitis caused by methyltetrahydrophthalic anhydride.

OBJECTIVE: To examine exposure-response relationships in the occurrence of symptoms of the eyes and airways in workers exposed to methyltetrahydrophthalic anhydride (MTHPA). METHODS: A population of 111 workers from 2 condenser plants (A and B) using epoxy resin with MTHPA underwent a questionnaire survey and serology investigations, and data obtained on 95 subjects in assembly and inspection lines were analyzed for this study. RESULTS: In all, 24 (65%) of 37 workers in plant A and 38 (66%) of 58 workers in plant B had positive MTHPA-specific IgE. The air levels of MTHPA detected in assembly and inspection lines were higher in plant A than in plant B (geometric mean 25.5-63.9 and 4.93-5.49 microg/m3, respectively). IgE-sensitized workers in each plant had significantly (P < 0.05) more complaints regarding the eyes and nose than did unsensitized workers, suggesting that there is an IgE-mediated mechanism in most of these symptoms. The sensitized workers in plant A had higher frequencies for symptoms of the eyes, nose, and pharynx than did those in plant B (P < 0.02). Furthermore, only 15% of persons often displayed work-related symptoms among the 20 symptomatic workers in plant B as compared with 73% of the 26 symptomatic workers in plant A (P < 0.0001). These results can be explained by the difference in the MTHPA levels measured in the lines between the two plants. In plant B the minimal level of MTHPA that was associated with work-related symptoms was 15-22 microg/m3, which was lower than the geometric mean levels detected in assembly and inspection lines in plant A. CONCLUSIONS: These results suggest that MTHPA exposure at levels above 15 microg/m3 should be avoided to prevent the development of occupational allergic diseases in most workers.