Geriatrics

1. Geriatrics Dr. S. Parthasarathy MD., DA., DNB, MD (Acu), Dip. Diab. DCA, Dip. Software statistics, PhD (physio) Mahatma Gandhi Medical college and research institute , puducherry India

2. What is the age ??Patients with more than 65

3. Why should we know ?? • By the year 2040, people aged 65 or older are expected to make up 24% of the population • Half will require surgery before they die, despite being at a 3-fold increased risk for peri operative death compared with younger patients • 160 crores - 40 crores – 20 crores – operation

4. Principles Two important principles • 1.progressive loss of functional reserve in all organ systems • 2. changes vary from person to person

5. Aging is a universal and progressive physiologic process • declining end-organ reserve, • May be normal organs • decreased functional capacity, • increasing imbalance of homeostatic mechanisms, • increasing pathologic processes • Limitation of function evident during stress

6. What is that stress ?? • exercise, • illness, • Surgery

7. Nervous System • Memory decline ( 40 % ) • Cerebral atrophy 15 % loss of neurons ( may be increased with comorbidities) Regional reductions in the neurotransmitters dopamine, acetylcholine, norepinephrine, and serotonin.

8. Anaesthetic implications of CNS changes • increased sensitivity to anaesthetic medications • increased risk for postoperative cognitive dysfunction. • reduction of the area of the epidural space • increased permeability of the dura • decreased volume of cerebrospinal fluid.

9. Cardiovascular System • Heart • Blood vessels • Autonomic control

10. Heart • Decreased contractility, • Increased myocardial stiffness and ventricular filling pressures • Decreased β-adrenergic sensitivity. • Fibrosis of the conduction system and loss of sinoatrial node cells increase the incidence of dysrhythmias, particularly atrial fibrillation and flutter

11. Heart – ctd. • Decreased ventricular compliance and increased afterload combine to cause a compensatory prolongation of myocardial contraction. • This occurs at the expense of a decreased early diastolic filling time. Under these conditions, the contribution of atrial contraction to late ventricular filling is more important • cardiac rhythm other than sinus is often poorly tolerated in elderly individuals.

12. Aortic valve sclerosis and mitral annular calcification are common echocardiographic findings in elderly patients • non–flow-limiting calcifications • Associated CAD

13. CVS • Arterial pressure waves, which normally reflect back towards the heart (arriving during diastole in young, healthy patients), travel more quickly and reach the heart during systole, forcing it to pump against itself and significantly reducing ventricular efficiency

14. Changes in the autonomic system • decrease in response to β-receptor stimulation • Baroreceptor function ?? • exercise or stress is associated with decreased maximal heart rate and decreased peak ejection fraction • increase in sympathetic nervous system activity • Intra operative hemodynamic lability. • Hypotension hypoxia – response ??

15. CCF – think of diastolic cause • No diuretics • No digoxin • adequate filling is key • attempt to maintain a slow heart rate and NSR • optimize blood volume,

16. To summarize

17. Respiratory System • Ventilatory response to hypoxia, hypercarbia Decreased • respiratory depressant effects of benzodiazepines, opioids, and volatile anaesthetics are exaggerated. • loss of elastic recoil • tendency for early collapse of the small airways on exhalation

18. Respiratory System • increases in size of the interalveolar pores of Kohn – less alveolar surface -- 70 % only • In younger individuals, closing capacity is below FRC • But in elderly ,CC above FRC, shunt increases, arterial oxygenation decreases

19. Respiratory System • AGE PaO2 • 20-29 94 • 60-69 81 • HPV is blunted in elderly individuals and may cause difficulty in OLV • Loss of height and calcification of the vertebral column and rib cage lead to a typical barrel chest appearance with diaphragmatic flattening

20. What is in lungs ??

21. Renal and Volume Regulation • Renal mass may decrease 30% by age 80 years • Means less glomuruli • Renal blood flow decrease 10 % / decade • But muscle mass decreases to make creatinine static • Inference ?? • Take BUN

22. Renal and Volume Regulation • ability to concentrate and dilute urine • risk of elderly patients for acute renal failure in the postoperative period. • elderly patient at risk for dehydration and sodium depletion (decreased thirst and salt intake ) fluid management more critical Handle a salt load ??

23. Hepatic Changes • Liver volume decreases approximately 20% to 40% with aging. • Hepatic blood flow decreases about 10% per decade • maintenance dose requirements in drugs that are rapidly metabolized – decreased

24. GIT • Plasma cholinesterase levels are reduced in elderly men. • Gastric pH tends to rise, whereas gastric emptying is prolonged, • although some studies suggest elderly patients have lower gastric volumes than younger patients.

25. Others • Veins are often frail and easily ruptured by intravenous infusion • Arthritic joints may interfere with positioning (eg, lithotomy) or regional anesthesia (eg, subarachnoid block). • Degenerative cervical spine disease can limit neck extension potentially making intubation difficult.

26. Musculoskeletal • Muscle mass is reduced • extrajunctional spread of acetylcholine receptors. • Skin atrophies with age and is prone to trauma from adhesive tape, electrocautery pads, and electrocardiographic electrodes

28. Visual impairment is common in elderly patients Hearing loss occurs linearly with age

29. Elderly and comorbid conditions • hypertension, diabetes mellitus, ischemic heart disease • malignancy. • Parkinson’ s • Old CVA , • Dementia • And associated polypharmacy

30. Consent • Cognitive and sensory difficulties frequently jeopardize informed consent in frail elderly patients. • Dementia, depression, hearing difficulties, and stroke all may interfere with the ability to make independent decisions • How can we explain risk surgeries ??

31. Metabolic & Endocrine Function • Insulin resistance • Heat production decreases, heat loss increases, and hypothalamic temperature-regulating centers may reset at a lower level • Hypothermia – never allow

32. Different presentation • Post op pneumonia • May present with • Confusion ,lethargy , hypoxemia

33.  Criteria Used to Define Frailty • Weight Loss Criterion • Exhaustion Criterion • Physical Activity Criterion • Walk Time Criterion • Grip test • Frailty refers to a loss of physiologic reserve

34. Often asked question-- Is she/he too old for surgery ??

35. Preoperative Evaluation • Routine • Airway – teeth • IV access • Spine access • Organ reserve

36. Pre anaesthetic check up • Background to admission. • Co-existing medical problems • Gastro-oesophageal reflux disease • Medications • social appraisal • Teeth and neck • Back

37. Difficult airway • Airway maintenance may be more difficult because of: • • Osteoporotic mandibles • • Nuisance/peg/loose teeth • • Temporo-mandibular joint stiffness • • Lax oropharyngeal muscle tone and edentulous jaws • • Cervical spondylosis • • Arthritis of atlanto-occipital joint

38. Premed • No atropine • Exception about atropine – dose more • No metoclopramide • Opioids, benz, ranitidine – ok

39. Principles in drug giving • The circulating level of albumin decreases with age, whereas α1-acid glycoprotein levels increase • Alb = acidic drugs • Α1 ag = basic drugs • decrease in lean body mass, an increase in body fat, and a decrease in total body water

40. Anaesthesia from here to there

41. General anaesthesia • Thio decreased – Vd decreased • . A prolonged circulation time delays the onset of intravenous drugs • Brain becomes more sensitive to the effects of propofol with age. • clearance of propofol is reduced • Midazolam 75 % dose

42. MAC decreases approximately 6% per decade • Recovery with a volatile anesthetic may be prolonged • because of an increased volume of distribution decreased hepatic function decreased pulmonary gas exchange. • The rapid elimination of desflurane may make it the inhalation anesthetic of choice for elderly patients.

43. Opioids and NMB s • All opioids almost twice as effective • Neuromuscular blockers : • Almost no change except if there is renal or hepatic problem • Decreased cardiac output and slow muscle blood flow, cause up to a 2-fold prolongation in onset of neuromuscular blockade • Cisatracurium – no change

44. Regional anaesthesia • The time of onset is decreased, • Spread is more extensive with hyperbaric bupivacaine solution • Reduced plasma clearance - beware in drug infusions

45. Regional • No airway • DVT • Pulmonary function • Drugs less esp. in renal and hepatic disease • Blood loss less technique ?? • Hypoxemia – less • Required doses of local anesthesia are reduced in spinals [Cameron et al. Anaesthesia 36: 318, 1981] as well as in epidurals • beware of nerve palsies, paresthesias

46. Postoperative Considerations • Pain = perception less • Functional reserve less • PAIN • Site specific blocks • IV paracetomol • NSAIDs • Opioids

47. Postoperative Considerations • DVT prophyl;axis • Nutrition • Calculated fluid management • Oxygen • Blood sugar monitoring • Temperature and shivers • Delirium

48. The incidence of common postoperative morbidities • In general surgical patients 65 years old and older, is • 17% for atelectasis, • 12% for acute bronchitis, • 10% for pneumonia, • 6% for heart failure or myocardial infarction (or both), • 7% for delirium, and 1% for new focal neurologic signs

49. The incidence of common postoperative morbidities • Type of surgery and presence of co morbidities

50. Future • Newer drugs • Video-assisted muscle-sparing minithoracotomy for major lung resection • Lap surgery