Productive Aging: A Quality of Life Agenda

Although the fact that, in general, the US population is living longer is said to be the public health success story of the 20th century, the boom in the population aged 65 years and older is having and will continue to have major implications for all age groups as well as for the nation's health, social, and economic institutions. The concept of productive aging can provide guidance in addressing these implications. The assumptions of productive aging reflect today's reality that older people are repositories of wisdom and experience and important assets for society; relatively healthy, with the potential for maintaining that condition until late in life; capable of making economic and social contributions that benefit themselves, their families, and their communities; and in need of purposeful and meaningful roles and activities in life. A productive aging activity model emphasizes involvement in paid work, volunteerism, education, fitness and exercise, leisure and travel, advocacy and political action, and consumerism. This article discusses the concept of productive aging, a related activity model, and qualitative focus group research undertaken in conjunction with the 1995 White House Conference on Aging. J Am Diet Assoc. 1998;98:1445–1448.     

Thermal filament continuous thermodilution cardiac output delayed response limits its value during acute hemodynamic instability.

BACKGROUND: It has been suggested that measurement of continuous cardiac output (CCO) is an advancement in the management of critically ill patients. Our objective was to determine the accuracy of CCO during the rapid hemodynamic changes induced by hemorrhage and resuscitation. METHODS: In 12 anesthetized dogs (20.2+/-0.9 kg), pulmonary artery blood flow, our "gold standard" cardiac output, was measured with an sonographic flowprobe, whereas CCO, intermittent bolus cardiac output (ICO), and mixed venous oxygen saturation were measured with a thermodilution fiberoptic pulmonary artery catheter with a thermal filament. A graded hemorrhage (20 mL/min) was produced to a mean arterial pressure of 40 mm Hg, which was maintained at this level for 30 minutes. Total shed blood volume (701+/-53 mL) was retransfused at a rate of 40 mL/min, over 30 minutes, after which a massive hemorrhage (100 mL/min) was produced over 10 minutes. RESULTS: Hemorrhage induced significant decreases in mean arterial pressure, mixed venous oxygen saturation, and oxygen delivery, which were all restored during early resuscitation. However, CCO showed a delayed response after hemorrhage and resuscitation, compared with pulmonary blood flow, throughout the study (r = 0.549), matching only at baseline and at the end of both graded hemorrhage and resuscitation periods. There was a good correlation between ICO and pulmonary artery blood flow (r = 0.964) and no significant differences between them throughout the study. CONCLUSION: CCO has a delayed response during acute hemodynamic changes induced by hemorrhage and resuscitation. When sudden changes in mean arterial pressure or in mixed venous oxygen saturation are detected, cardiac output must be estimated by the standard bolus thermodilution technique, not by CCO.