2004 OPEN FORUM Abstracts
MITIGATION OF OCCUPATIONAL EXPOSURE TO AEROSOLIZED MEDICATIONS.
McPeck BS RRT FAARC, Glenn Samford CNMT, Ross Potter CNMT and
Russell King. Healthline Aerosol Medicine, Baldwin Park CA.
BACKGROUND: Current aerosol drugs administered by small volume nebulizers (SVNs) include beta agonists, anticholinergics, antibiotics, pulmonary vascular regulators, opioids and others. There is sparse data concerning respiratory therapists’ (RTs’) occupational exposure to medicated aerosols. Common sense suggests that inhaling aerosol medications should be avoided or mitigated while providing therapy. The Healthline Medicator® Aerosol Maximizer is claimed to markedly reduce the amount of “Waste Aerosol” (WA), aerosol that is generated but not inhaled, released to the room. It uses a special manifold, unidirectional flow control valve and 1 L latex-free reservoir bag that stores most of the aerosol generated during the patient’s exhalation phase, which would otherwise be vented to the room, and allows it to be inhaled by the patient on the subsequent breath. We sought to determine whether the Medicator® achieves a reduction in WA and, if so, by how much.
METHODS: We tested 9 different models of plastic disposable jet SVNs that were available to us in our facility. Each SVN was loaded with ~3.2 mL of radiolabeled (99mTc) 0.083% unit-dose albuterol and run at 7 L/min with O2. A sine wave ventilator produced a simulated adult breathing pattern (VT = 600 mL; f = 12 BPM, I:E = 1:2) that was used to draw aerosol into a HEPA filter representing the mouth while another HEPA filter captured only WA that would have exited the exhalation port in the absence of a filter. There was no exhaled aerosol in the bench model because all inhaled aerosol was trapped on the inspiratory filter. SVNs were tested on both a Tee setup and when attached to the Medicator® manifold. Each SVN was run until it stopped producing aerosol (~ 9 mins). The SVNs and HEPA filters were measured in a radioisotope counter and the WA fraction (radioactivity on waste filter / radioactivity of initial nebulizer charge) was determined.
RESULTS: The WA for the 9 SVNs varied from 21.7 to 36.0% (mean ±SD = 27.3 ±4.9%) on the Tee setup and from 7.6 to 12.9% (mean ±SD = 9.6 ±2.0%) on the Medicator® (the t-statistic was significant at the .025 critical level, p = .0000 by matched-pairs t-test).
CONCLUSION: Because the Medicator® stores aerosol generated during exhalation in a 1 L reservoir bag and returns it to the patient on the following breath, this appears on the test bench to significantly reduce the amount of WA vented to the room and presumably would mitigate occupational exposure of RTs to aerosolized drugs.