Pacific Northwest survey: posttympanostomy tube water precautions.

OBJECTIVES: To determine what recommendations are given to patients or parents of patients with tympanostomy tubes regarding water exposure and to elucidate any recommendation differences between primary care and specialty care physicians. DESIGN: Clinical survey. SETTING: General community in the Pacific Northwest, including Washington, Oregon, and Idaho. PARTICIPANTS: Physician surveys (N = 1116) were mailed to otolaryngologists, pediatricians, and family practitioners in the Pacific Northwest. Questions included what, if any, water precautions are given to patients or parents of patients who underwent tympanostomy tube insertion. Data were tabulated and compared among the 3 physician groups. MAIN OUTCOME MEASURES: Recommendations regarding water exposure. RESULTS: A response rate of 23.5% (n = 263) was obtained. Most respondents were self-described otolaryngologists (n = 150) followed by family practitioners (n = 77) and pediatricians (n = 36). chi(2) Analysis of the responses from each specialty group showed an overall significant difference about swimming precautions (P < .001). Further analysis of these data shows that many otolaryngologists (47% [n = 71]) and most primary care physicians (73% [n = 83]) recommend the use of barrier devices for swimming. Another 47% of otolaryngologist respondents allow swimming without any water precautions. With regard to depth of dive, there was no statistical significance found between the physician groups. CONCLUSIONS: Recommendations for swimming precautions are not universal among the physician groups that routinely see patients with tympanostomy tubes. Most primary care physicians and many otolaryngologists continue to prescribe water precautions to patients or parents of patients with tympanostomy tubes, despite published articles that have shown no reduction in the incidence of otorrhea from the use of barrier devices or from the avoidance of swimming.

Intracellular calcium activity in isolated bovine adrenal chromaffin cells in the presence and absence of 60 Hz magnetic fields.

This study examined whether 60 Hz magnetic field (MF) exposure alters intracellular calcium levels ([Ca(2+)](i)) in isolated bovine adrenal chromaffin cells, a classic model of neural responses. [Ca(2+)](i) was monitored by fluorescence video imaging of cells loaded with the calcium indicator fluo-4 during exposures to magnetic flux densities of 0.01, 0.1, 1.0, 1.4, or 2.0 mT. MFs generated by Helmholtz coils constructed from bifilar wire allowed both 60 Hz field and sham exposures. Following a 5 min monitoring period to establish baseline patterns, cells were subjected for 10 min to a 60 Hz MF, sham field or no field. Reference calcium responses and assessment of cell excitability were obtained by the sequential addition of the nicotinic cholinergic receptor agonist dimethylphenylpiperazinium (DMPP) and a depolarizing concentration of KCl. Throughout an 8 day culture period, cells exhibited spontaneous fluctuations in [Ca(2+)](i). Comparisons of the number of cells exhibiting transients, the number and types of calcium transients, as well as the time during monitoring when transients occurred showed no significant differences between MF exposed cells and either sham exposed or nonexposed cells. With respect to the percentage of cells responding to DMPP, differences between 1 and 2 mT exposed cells and both nonexposed and sham exposed cells reached statistical significance during the first day in culture. No statistically significant differences were observed for responses to KCl. In summary, our data indicate that [Ca(2+)](i) in chromaffin cells is unaffected by the specific 60 Hz MF intensities used in this study. On the other hand, plasma membrane nicotinic receptors may be affected in a manner that is important for ligand-receptor interactions.