Geriatrics

·         The "thermostat" within the hypothalamus is less responsive to changes in both skin temperature and core temperature and therefore signals shivering to begin at a lower temperature. Shivering in the elderly does generate normal amounts of heat, but the loss of subcutaneous tissue with aging results in a loss of insulation, leading to more rapid loss or gain of heat. Additionally, the basal metabolic rate of the older person is lower, resulting in less heat to conserve. Finally, some older people may have a reduced drive to microacclimatize (put on warm clothing) when the surroundings are cold. All of these small changes (especially in the presence of impaired cognition or sedative medications) can add up to a large risk of accidental hypothermia.

·         Blood flow decreases in both the arterial and portal systems IN LIVER, contributing to increases in the half-life of certain agents and narrowing the oral dose/parenteral dose discrepancies for drugs that are heavily metabolized during the "first pass" through the liver

·         Phase I reactions, oxidations and reductions, decrease

·         Phase II reactions, acetylations and glucuronidations, are generally unchanged

·         There is no age-associated decrease in hemoglobin in healthy men and women.

·         Older persons spend more time in stage I (light sleep/sleep-awake transition) and less time in stage IV sleep.

·         The Diogenes syndrome is a condition of self-neglect, independent of depression and cognitive impairment, that may represent the evolution of a personality disorder. Individuals are unkempt and may often exhibit hoarding behavior. As they retreat socially, their behavior may preclude proper nutrition so that malnutrition is common. The 1-year mortality rate may be as high as 50%.

·         Diastolic dysfunction results from impaired relaxation in heart failure with preserved ejection fracture and may account for half of all cases of heart failure in people over 80. Clinically, the symptoms may be similar to those of systolic dysfunction, but the traditional therapy for systolic dysfunction can actually worsen ventricular filling and increase the risk of orthostasis and syncope. Treatment for diastolic dysfunction may include calcium channel blockers or beta blockers.

·         An S4 likely results from the decreased compliance of the ventricular septum and is very common in older persons and usually of limited clinical significance. The presence of an S3 gallop, however, is never normal in an older person and is characteristic of CHF.

·         Aortic sclerosis is the source of many benign murmurs in the elderly, resulting from hardening and fibrosis of the aortic cusps, and is not hemodynamically significant.

·         A fifth agent, memantine, targets acetylbuterase and also appears to slow the progression of the AD.

An advanced directive is a personal written or oral statement indicating preferences for end-of-life therapies. A living will is an example of an advanced directive. Living wills typically state that a person does not want life-sustaining treatments such as artificial ventilation or resuscitation started or continued if he or she has a terminal illness without the hope of effective treatment. A durable power of health care (DPAHC) designates the medical decision maker for a person who is unable to make his or her own treatment decisions because of incapacity or severe medical illness.