Respiratory system changes The respiratory system includes the thoracic cage (which encompasses the ribs, thoracic vertebrae, and intercostal muscles), lungs, and diaphragm. It is theorized that, as in the cardiovascular system, a lifetime of cellular stress and damage leads to changes in the lung’s tissue as well as in the thoracic cage and diaphragm, resulting in decreased function of the respiratory system with aging. At a cellular level, there are numerous changes in the lung tissue, or parenchyma, including a decrease in the elastic tissue within the lungs that results in a decrease in the elastic recoil of the lungs as well as a premature closure of small airways during normal breathing. This results in air trapping and an inability to completely empty the lungs (Sharma & Goodwin, 2006). At the same time, cellular changes in the thoracic cage result in an increased stiffness of the intercostal muscles and calcification of the costal cartilages, resulting in decreased ability of the lungs to expand. Osteoporosis and a lifetime of poor posture may also contribute to the development or worsening of kyphotic posture due to reduced height of the thoracic vertebrae and a collapse of the thoracic intervertebral discs (Chester & Rudolph, 2011). As a result of the structural changes in the thoracic cage and an increase in kyphotic This is the amount of air that can be inhaled or exhaled during one respiratory cycle. The normal adult value is 10% of vital capacity, which is approximately 300–500 mL (Physiopedia, 2022). Inspiratory volume This is the amount of air that can be forcibly inhaled after a normal tidal volume. Inspiratory reserve volume (IRV) is usually kept in reserve and is used during deep breathing. The normal adult value is 1,900–3,300mL (Physiopedia, 2022). Expiratory volume This is the volume of air that can be exhaled forcibly after exhalation of normal tidal volume. The normal adult value Endocrine system changes The endocrine system is responsible for regulating the body’s metabolism through the release of hormones that act as signals to cells throughout the body. These chemical messengers act to coordinate a whole-body response among various systems. For example, the release of the hormone insulin from the pancreas results in an increased uptake of glucose in most cells of the body. Aging is associated with numerous changes in the release and regulation of multiple hormones that result in changes in whole-body fat mass, increased inflammation, and increased risk for metabolic diseases such as diabetes (Davan-Wetton et al., 2021). The endocrine system also has complex interrelationships with the brain, immune system, and skeletal muscles (Clegg & Hassan-Smith, 2018). “The brain and endocrine system are intrinsically linked through the hypothalamic-pituitary axis, which controls metabolism and energy use via the signaling of several homeostatic hormones” (Clegg & Hassan-Smith, 2018, p. 744). In addition to the hypothalamic–pituitary axis, vitamin D and insulin resistance might have a potential role in the pathogenesis of frailty (Clegg & Hassan-Smith, 2018). The hypothalamus receives and integrates brain inputs to coordinate the body’s response to stress and inflammation, partly through the control of glucocorticoid secretion (Clegg & Hassan-Smith, 2018). While it is not clear if glucocorticoid secretion increases with age, age-related changes to the hypothalamic–pituitary– adrenal axis are evident in the blunting of the circadian rhythm, reduced suppression of cortisol secretion, and impaired recovery from stress (Clegg & Hassan-Smith, 2018). Glucocorticoids are involved in a range of metabolically active tissues, including skeletal muscle, bone, and the cardiovascular system (Clegg & Hassan-Smith, 2018). It has been shown that glucocorticoids
posture, there is a loss of chest wall compliance, or the ability of the chest to expand with inhalation. The decreased chest wall compliance results in an increased amount of work necessary to bring in a normal volume of air. The increase in kyphotic posture additionally places the diaphragm at a mechanical disadvantage and reduces its efficiency of contraction (Chester & Rudolph, 2011), which, when combined with the decreased strength of the diaphragm that occurs with aging, results in further decreases in the efficiency of breathing (Sharma & Goodwin, 2006). The combination of a loss of elastic recoil in the lungs with a decrease in chest wall compliance, along with functional changes in the ability of the diaphragm to efficiently contract, result in increased work to breathe and decreases physiologic reserve for the respiratory system. Similar to the cardiovascular system, at rest there may be minimal changes in older adults, as they are able to compensate and adapt. One such example of adaptation is seen in the increased respiratory rate that many older adults experience (Cester & Rudolph, 2011). However, with a stressful systemic event, such as surgery or illness, many older adults may be unable to compensate and will experience declines in respiratory function (Chester & Rudolph, 2011). is 700–1200 mL. Expiratory reserve volume (ERV) is reduced with obesity and ascites, as well as following upper abdominal surgery (Physiopedia, 2022). Respiratory rate To assess your own respiratory rate: 1. Sit down and try to relax. It's best to take your respiratory rate while sitting up in a chair or in bed. 2. Measure your breathing rate by counting the number of times your chest or abdomen rises over the course of one minute. 3. Record this number. (Mayo Clinic, 2022) relate proportionately to cortisol, and high cortisol is related to the catabolism of skeletal muscle and accumulation of fat. Total- body fat mass typically increases until age 65 and then either decreases or remains the same (Barzilai et al., 2012). As an individual ages, fat is no longer stored in the subcutaneous fat depot beneath the skin; rather, it is instead stored in other more harmful locations, such as in and around the abdominal organs and underneath the muscle fascia in and between muscle fibers. These alternate locations of fat storage, also known as ectopic fat deposits , result in increased release of proinflammatory cytokines from adipose tissue and increased whole-body inflammation (Barzilai et al., 2012; Davan-Wetton et al., 2021). Increased amounts of adipose tissue release a host of hormones and proinflammatory cytokines that have negative effects on mobility and function in older adults (Clegg & Hassan- Smith, 2018; Marcus et al., 2012). Uncontrolled inflammation has the potential to cause cellular damage, jeopardizing homeostatic regulation of the body at a local and a systemic level (Clegg & Hassan-Smith, 2018). Inflammation is typically a protective response triggered by infections and tissue damage. It is a glucocorticoid response intended to remove noxious stimuli and pathogens, restore physiological homeostasis, and help resolve infections and wound healing (Clegg & Hassan-Smith, 2018). If the mechanisms of inflammatory response are compromised, cellular damage occurs, accelerating the mechanisms of frailty (Clegg & Hassan-Smith, 2018). However, not all adipose tissue is equally harmful. Adipose tissue stored in the subcutaneous tissue poses less of a health risk than adipose tissue stored in the abdominal cavity, which is also known as visceral adipose
Measurement of inspiratory and expiratory volume and respiratory rate Tidal volume
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Book Code: PTNY1024
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