Search PubMed⌕ Search

Biomedical subjects

R A Malone

Publications and source records attributed to R A Malone.

4 recordsLinked to original sources
PubMed1993

Optimal duration of nebulized albuterol therapy.

The output from a jet nebulizer was analyzed for aerosol profile, solution output, and delivery of albuterol at three different initial volume fills to determine the changes that occur during the course of nebulization. Increasing diluent volume led to significantly greater delivery of the albuterol initially placed in the nebulizer. Albuterol delivery from the nebulizer ceased completely following the onset of inconsistent nebulization (sputtering) as determined audibly and by laser particle analysis. Aerosol output rate declined by one-half within 20 s of the onset of sputtering. The albuterol concentration in the nebulizer solution increased significantly once the aerosol output declined. The weight of solution delivered as determined by change in weight of the nebulizer could not be fully accounted for as aerosol volume. It appeared that this discrepancy represented loss of water by evaporation. Aerosolization past the point of initial jet nebulizer sputtering is unproductive.

Administration, Inhalation↗
PubMed1991

Extreme variability in aerosol output of the DeVilbiss 646 jet nebulizer.

Ten new jet nebulizers (DeVilbiss 646) were studied to determine their consistency of output. Each nebulizer, containing 2 ml of saline solution, was run for 1 min in triplicate at four different straw (capillary tube) positions, keeping all other variables constant. Total output in milliliters per minute and volume of aerosol in the respirable range (1.0 to 5.0 microns) were measured. There was significant variability in output and volume of output in the respirable range (VORR) for every nebulizer at each of the tested straw positions (p less than 0.0001). Irregularities in manufacture of the bowl and straw appear to be responsible for this significant variability. In summary, there is considerable intranebulizer and internebulizer variability that could influence both patient care and medical use for diagnostic purposes.

Confidence Intervals↗
PubMed1977

Plasma osmotic changes during major abdominal surgery.

Fluid balance across the capillary membrane is maintained normally by a balance of hydrostatic and colloid osmotic pressures (COP). In 12 patients having major intra-abdominal procedures, the COP was followed during the operative and immediate postoperative periods. The patients' intraoperative fluid management consisted of replacing shed blood with blood and following Shires' concept of crystalloid replacement. Significant decreases in COP to approximately two thirds of the initial value occurred in patients having intra-abdominal procedures versus only a 10 percent decrease in those having peripheral procedures (greater than .001). As a result of this decrease in COP, the balance between hydrostatic and colloid osmotic pressures is lost and risk of pulmonary intersitial edema is increased.

Abdomen↗