1
Pathophysiological changes in the elderly

https://doi.org/10.1016/S1521-6896(03)00010-7Get rights and content

Abstract

Demographic data indicate an increasing workload of geriatric anaesthesia due to advancing life expectancy and reduced thresholds for high-invasive and high-risk surgery in the elderly. Chronological and biological age may be inconsistent, and the existence of age-related changes may vary between organ systems in the same individual. Age itself is not an illness, but is the most important contributing factor for perioperative complications and adverse outcome when the overall narrowed margins of organ function reserve are transgressed during the perioperative period. Age-related changes in the cardiovascular, pulmonary, nervous, metabolic and locomotive systems that are frequently present in the elderly are discussed with regard to their potential relevance to anaesthesiology.

In conclusion, listing current diagnoses will not be sufficient in the assessment of the geriatric patient because age-related changes do not necessarily manifest as pathological entities. Rather, pre-operative examination should focus on determination of individual margins of organ function reserve.

Section snippets

Increasing life expectancy

In recent decades life expectancy in the USA and Europe has been prolonged in men and women to approximately 74 years and 80 years, respectively. Many factors contribute to this development, but medical progress seems to be the most effective one.1 Demographical data indicate that the elderly are the most rapidly growing segment of the population in industrialized countries.

Currently, in Europe, inhabitants aged 65 and older represent 15–19% of the population. It is estimated for the year 2025

Heart

Age-related cardiovascular morbidity and mortality has been determined to be the main contributor in cases of overall adverse perioperative outcome.18

Cardiovascular reserve is strongly affected by ageing. Stress factors—such as increased flow demand by physical exercise, or post-operative demand due to acute autonomic reflex control (e.g. change of posture) or severe disease with hyperdynamic response (myocardial ischaemia, tachyarrhythmia, uncontrolled hypertension)—may induce a rapid

Changes in volumes

Ageing is characterized by a loss of elastic recoil of the lungs and impaired thoracic movement for inducing intrathoracic volume changes, resulting in a shift of the pressure–volume curve to the left.45 Static lung compliance increases with age, whereas dynamic compliance becomes more frequency dependent. Airway conductance is not altered by ageing.46

The total lung capacity is not subject to change during the course of life, but it is important to note changes of functional volumes reflected

Kidneys

The kidneys are characterized by a progressive reduction of renal mass with ageing due to glomerulosclerosis, paralleled by thickening of the vascular intima, fibrosis of the stoma and chronic infiltration by inflammatory cells. Glomerulosclerosis results in a decline in renal plasma flow (RPF) and glomerular filtration rate (GFR).51 Because GFR diminishes less than RPF, the filtration fraction increases to a state of hyperfiltration that, to some extent, represents a mechanism for adaptation

Drug therapy

Ageing of the nervous system is characterized by a general loss of neuronal substance. The most obvious sign is a reduced average brain weight in the elderly; brain weight was reported to be 1375 g at age 20 and 1200 g at age 80.76 The number of peripheral neurons also decreases, and muscles become innervated, overall, by fewer axons, possibly leading to denervation atrophy. A particular neuromuscular junction is not functionally changed with ageing. The plasma concentration of pancuronium

The locomotive system

Shrinkage of body height with ageing occurs because of the tendency of the cervical and thoracal spine towards hyperlordosis due to atrophy of the muscle groups of the back that usually erect the spine. Additionally, there is a reduction in height of the intervertebral discs due to changes in collagen content and architecture which add up to a reduction in height of about 5 to 7 cm when comparing age 20 with age 70; this occasionally increases the technical difficulties of spinal anaesthesia.92

Conclusion

Old age can be characterized as a continuation of life with decreasing capacities for adaptation.101 Changes in organ function may not be apparent in normal life, but may be revealed by narrowed margins of reserve to unusual exertion during surgery and anaesthesia. This is also true for the care-givers of anaesthesia themselves; although, in general, physicians tend to deny issues involving their own ageing, 80% of anaesthesiologists older than 50 were reported to have already planned their

References (104)

  • P.E Macintyre et al.

    Age is the best predictor of postoperative morphine requirements

    Pain

    (1996)
  • J.T Moller et al.

    Long-term postoperative cognitive dysfunction in the elderly: ISPOCD 1 Study

    Lancet

    (1998)
  • M.J Tessler et al.

    The performance of spinal anaesthesia is marginally more difficult in the elderly

    Regional Anaesthesia and Pain Medicine

    (1999)
  • E.L Schneider

    Aging in the third Millennium

    Science

    (1999)
  • The World Health Report : Life in the 21st Century–a Vision for All

    (1998)
  • G.A Rooke et al.

    Anesthesiology and geriatric medicine

    Anesthesiology

    (2002)
  • Statistical Abstracts of the United States

    (1993)
  • J.C Day

    Current Population Report, Bureau of the Census

    (1996)
  • B.T Veering

    Management of anaesthesia in elderly patients

    Current Opinion in Anaesthesiology

    (1999)
  • C.E Klopfenstein et al.

    The influence of an ageing surgical population on the anaesthesia workload: a ten-year survey

    Anaesthesia and Analgesia

    (1998)
  • F Clergue et al.

    French survey of anaesthesia in 1996

    Anesthesiology

    (1999)
  • V.S Musunuru

    The geriatric patient

  • N Burns-Cox et al.

    Surgical care and outcome for patients in their nineties

    British Journal of Surgery

    (1997)
  • International Classification of Diseases, 10th Revision. Geneva: World Health Organization,...
  • G.A Rooke et al.

    Hemodynamic response and change in organ blood volume during spinal anaesthesia in elderly men with cardiac disease

    Anaesthesia and Analgesia

    (1997)
  • H.H Lim et al.

    The use of intravenous atropine after a saline infusion in the prevention of spinal anaesthesia-induced hypotension in the elderly

    Anaesthesia and Analgesia

    (2000)
  • C.A Polanczyk et al.

    Impact of age on perioperative complications and length of stay in patients undergoing noncardiac surgery

    Annals of Internal Medicine

    (2001)
  • D.R Thomas et al.

    Preoperative assessment of older adults

    Journal of the American Geriatric Society

    (1995)
  • M.Y Rady et al.

    Perioperative determinants of morbidity and mortality in elderly patients undergoing cardiac surgery

    Critical Care Medicine

    (1998)
  • D.T Mangano

    Perioperative cardiac morbidity

    Anesthesiology

    (1990)
  • H.J Priebe

    The aged cardiovascular risk patient

    British Journal of Anaesthesia

    (2001)
  • E.G Lakatta

    Changes in cardiovascular function with aging

    European Heart Journal

    (1990)
  • G Olivetti et al.

    Cardiomyopathy of the aging human heart. Myocyte loss and reactive cellular hypertrophy

    Circulation Research

    (1991)
  • E.G Lakatta

    Cardiovascular aging research: the next horizons

    Journal of the American Geriatric Society

    (1999)
  • D Amar et al.

    Older age is the strongest predictor of postoperative atrial fibrillation

    Anesthesiology

    (2002)
  • D.T Wong et al.

    Carotid endarterectomy and abdominal aortic aneurysm repair: are these reasonable treatments for patients over age 80

    American Journal of Surgery

    (1998)
  • P Kolh et al.

    Cardiac surgery in octogenarians—peri-operative outcome and long-term results

    European Heart Journal

    (2001)
  • A Kudoh et al.

    Endocrine response to surgical stress in three patients over 100 yr

    Canadian Journal of Anaesthesia

    (2001)
  • M White et al.

    Age-related changes in beta-adrenergic neuroeffector systems in the human heart

    Circulation

    (1994)
  • P.A van Zwieten

    Pharmacological backgrounds of hypertension in the elderly

    Blood Pressure

    (1995)
  • S.C Montamat et al.

    Physiological response to isoproterenol and coupling of beta-adrenergic receptors in young and elderly human subjects

    Journal of Gerontology

    (1989)
  • D Fitzgerald et al.

    Cardiac sensitivity to isoprenaline, lymphocyte beta-adrenoceptors and age

    Clinical Science

    (1984)
  • J.A Heinsimer et al.

    The impact of aging on adrenergic receptor function: clinical and biochemical aspects

    Journal of the American Geriatric Society

    (1986)
  • R.D Feldman et al.

    G-protein alterations in hypertension and aging

    Hypertension

    (1995)
  • P.M Colangelo et al.

    Age and beta-adrenergic receptor sensitivity to S(−) and R,S (+/−)-propranolol in humans

    Clinical Pharmacological Therapy

    (1992)
  • R.E Vestal et al.

    Reduced beta-adrenoceptor sensivity in the elderly

    Clinical Pharmacological Therapy

    (1979)
  • J.A Taylor et al.

    Lesser vagal withdrawal during isometric exercise with age

    Journal of Applied Physiology

    (1995)
  • T.J Ebert et al.

    Effects of aging on baroreflex regulation of sympathetic activity in humans

    Journal of Applied Physiology

    (1992)
  • T.B.J Kuo et al.

    Effect of aging on gender differences in neural control of heart rate

    Journal of Applied Physiology

    (1999)
  • M.G Hopkins et al.

    Enhanced beta-adrenergic-mediated cardiovascular response in endurance athletes

    Journal of Applied Physiology

    (1996)
  • Cited by (0)

    View full text