Donna Carter | PubMed Health

PubMed2006

Inactive nurses: a source for alleviating the nursing shortage?

OBJECTIVE: This study seeks to provide an understanding of why inactive registered nurses chose to become inactive and what they would require for them to return to nursing. BACKGROUND: In 2000, a shortage of 110,000 (6%) registered nurses existed in the United States. If the current trends continue, the shortage is projected to grow to 29% by 2020. One solution to the nursing shortage may be attracting nurses with inactive licenses back into employment. METHODS: This study used a quantitative, cross-sectional survey design. Data analysis included descriptive and inferential statistics. RESULTS: Inactive nurses (N = 428) younger than 60 years in 1 Southern state were surveyed. A major portion (27.6%) of these nurses left nursing because of a conflict between parenting duties and scheduling requirements (13.5%) at work and indicated that they would return to nursing if given the opportunity to work part-time, especially if shifts were flexible and shorter. CONCLUSION: Although the group of registered nurses younger than 60 years do not constitute a large percentage of nurses in this country, they are a potential source of alleviating, to some extent, the critical nursing shortage. Employers can encourage many of these nurses to return to work by providing more flexible work schedules, including part-time and shorter shifts, as well as decreased workloads.

Adult↗

PubMed2002

Estimation of human corneal oxygen consumption by noninvasive measurement of tear oxygen tension while wearing hydrogel lenses.

PURPOSE: To devise a procedure for direct estimation of corneal oxygen consumption in human subjects. METHODS: Tear oxygen tension (PO2) was measured at the posterior surface of two standard hydrogel contact lenses (38% water, 0.2 and 0.06 mm thick, oxygen transmissibility [Dk/t] = 4.2 and 14 x 10(-9) cm x mL O2/mL x sec x torr) and one newly available hydrogel-silicone polymer lens (Dk/t = 99 x 10(-9)). The oxygen-sensitive dye, Pd-meso-tetra (4-carboxyphenyl) porphine, bound to bovine serum albumin, was incubated with the lenses overnight. The lenses, coated with the protein-dye complex, were placed on four subjects' eyes, and tear PO2 was measured in the open eye and after 5 minutes of eye closure, using a time-domain phosphorescence measurement system. Given the tear PO2, lens Dk/t, and corneal thickness, oxygen consumption (Q(C), in mL O2/cm(3) x sec) could be calculated from established oxygen diffusion models. RESULTS: Protein-dye complex bound to the lens surface enabled reporting of tear PO2 for long periods. As expected, estimated tear PO2 was higher in subjects wearing lenses with higher Dk/t: mean open-eye PO2 = 30.6 +/- 3.1 and 8.1 +/- 1.3 torr for the thin and thick hydrogel lenses, respectively, and 97.6 +/- 22.9 torr for the hydrogel-silicone lens. After 5 minutes of eye closure, tear PO2 was significantly reduced and reached a new steady state in approximately 20 seconds after eye opening. Fitting a single exponential model to the data and extrapolating to t = 0 provided an estimate of PO2 under the closed lid for the thin hydrogel (PO2 = 7 +/- 2.3 torr) and the hydrogel-silicone lens (PO2 = 22.6 +/- 4 torr). After 5 minutes of eye closure with the thick hydrogel lens, tear PO2 remained constant for approximately 10 seconds after eye opening (mean PO2 = 3.9 +/- 0.7) before increasing to a new steady state. This delay could be accounted for by the time needed for oxygen to diffuse to the posterior surface of the lens. Calculated Q(C) ranged from 2.2 x 10(-4) to 3.7 x 10(-6) mL O2/cm(3) x sec) at the highest and lowest PO2s, respectively, and is comparable to previous in vitro and in vivo estimates. CONCLUSIONS: Tear PO2 behind hydrogel lenses can be measured in human subjects using the phosphorescence of the porphyrin-protein complex bound to the lens surface. The method is simple, fast, reliable, and noninvasive, allowing quick and direct estimates of Q(C). In addition to contact lens wear, this method should be useful for examining the effects of disease, surgery, or topical drugs on the corneal oxygen consumption rate.

Adult↗