Creating greater efficiency in ambulatory surgery.

Ambulatory surgery emerged as a new modality in health care 25 years ago, and it has continued to grow substantially since that time. Several thousand facilities and programs have been established, developed, and expanded, while hundreds of millions of dollars were expended and committed to react to industry demands. Ambulatory surgery growth between 1970 and 1980 (Figure 1) was primarily fueled by patient, physician, and cost considerations. Surgical facilities and programs were initially faced with establishing credibility and legitimacy by demonstrating safety and quality in the outpatient setting. Thus began the competition for the ambulatory surgery patient in the United States. Ambulatory surgery became synonymous with efficiency in that there was a reduction in overnight stays, lowering the cost for the ambulatory surgery patient and providing hospital beds for those who required them. In addition, ambulatory surgery centers' fees were initially considerably less than hospital ambulatory surgery fees. Between 1980 and 1990 (Figure 2), the principal influences in ambulatory surgery expanded from surgeons and patients to include insurance companies and government reimbursement programs, including Medicare and Medicaid. A substantial growth in technology occurred, the investment community discovered ambulatory surgery, and an increase in reimbursement was a result of those marketplace dynamics. From 1990 (Figure 3) to the present, principal influences expanded from surgeons, patients, insurance, and government, to include managed care, creative alliances, affiliations, and employers. The health care industry is now dominated by cost control, competition, exclusionary contracts, changing referral patterns, fragmentation, self-referral legislation, continuing governmental regulations, consumerism, accountability and measurability, over-capacity, capital limitations, and technological advances. Health care clinicians and analysts comfortably project that, by the year 2000, 75% of all surgery will be performed on an ambulatory basis./4+ key/(ABSTRACT TRUNCATED AT 400 WORDS)

Ecologic and Paleoclimatic Implications of Morphologic Variation of Orbulina universa in the Indian Ocean.

Multivariate cluster analysis of various morphologic indices of Orbulina universa populations from the Indian Ocean indicate the existence of two major groups whose geographic distribution corresponds to the equatorial and central water masses. An abrupt change in shell porosity between populations of this planktonic foraminiferal species in plankton as well as sediment samples occurs within or near the 10 degrees S Hydrochemical Front. Orbulina universa is an excellent indicator of oceanographic conditions in the Indian Ocean today, and may be used as an independent check on shifts in water masses during the last glaciation.

Oxygen-18 studies of recent planktonic Foraminifera: comparisons of phenotypes and of test parts.

Oxygen isotopic comparisons of phenotypes of Recent Planktonic Foraminifera with both normal and diminutive final chambers are compatible with a model in which the latter develop as a response to environmental stress. Isotopic evidence shows that Spheroidinella dehiscens is probably not a late-stage, aberrant form of Globogerinoides sacculifer.