Preoperative Assessment in the Older Adult

1
Preoperative Assessment in the Older Adult

• Lisa Caruso, MD, MPH
• Section of Geriatrics
• Boston University Medical Center

2
Goals

• To review the most common physiologic changes in
  the elderly which may impair ones ability to
  compensate for operative stress
• To describe the purpose of the preoperative
  assessment
• To provide strategies to minimize operative risks

3
Cardiovascular System

• Changes in mechanics
• Decrease in myocytes, increase in collagen
  resulting in decreased compliance
• Autonomic tissue replaced by collagen resulting
  in conduction abnormalities
• Decreased compliance of vascular system leading
  to increased systolic blood pressure with
  resulting ventricular hypertrophy

4
Cardiovascular System

• Changes in control mechanisms
• decreased responsiveness to catacholamines due
  probably to impaired receptor function
• decreased heart rate response to changes in
  circulatory volume may lead to congestive heart
  failure or hypotension (COSV x HR gtpreload
  dependency)

5
Pulmonary System

• Reduced chest wall compliance resulting in
• increased work of breathing
• reduced maximal minute ventilation
• Reduced respiratory response to hypoxia by 50 (?
  Due to impaired chemoreceptor function)
• Decreased ciliary function
• Reduced cough and swallowing function

6
Neurologic Changes

• Decrease in cortical gray matter, neuronal
  volume, complexity of neuronal connections,
  synthesis of neurotransmitters
• Neuronal loss and demyelination occur in the
  spinal cord resulting in changes in reflexes and
  reductions in proprioception
• Vision and hearing loss make information
  processing more difficult

7
Renal Changes

• Decline in renal blood flow--10 per decade after
  age 50
• Old kidney has difficulty
• maintaining circulating blood volume
• with sodium homeostasis
• removing excess acid
• adjusting to hypovolemia, hemorrhage, low cardiac
  output and hypotension
• Renal insufficiency may not be appreciated

8
Adverse Drug Reactions (ADR)

• Decrease in lean body mass with increased
  proportion of body fat
• Decreased protein binding of certain drugs
• Alterations in renal, CV, hepatic function may
  change drug concentrations and their duration of
  action
• ADRs increase with number of drugs administered
  and linearly with age

9
(No Transcript)
10
Preoperative Assessment--Purposes

• Not just for clearance
• To identify factors associated with increased
  risks of specific complications related to a
  procedure
• To recommend a management plan to minimize these
  risks

Cassel CK, Leipzig RM, Cohen HJ, et al. Geriatric
Medicine An Evidence Based Approach, 4th ed. New
York Springer 2003.
11
Preoperative Assessment--Components

• Functional Assessment
• Cognitive Assessment
• Nutritional Assessment
• Review of advance directives
• whether and when to withhold or withdraw support

12
Functional Assessment

• American Society of Anesthesiologists (ASA) score
• Class I A normal healthy patient for elective
  operation
• Class II A patient with mild systemic disease
• Class III A patient with severe systemic disease
  that limits activity but is not incapacitating
• Class IV A patient with incapacitating systemic
  disease that is a constant threat to life
• Class V A moribund patient that is not expected
  to survive 24 hrs with or without the operation

13
Functional Assessment

• Exercise capacity
• inactive defined as inability to leave the home
  on ones own at least twice per week
• increased CV risk in patients unable to meet a
  4-MET demand during most daily activities
• Activities of Daily Living
• Correlated with post-op morbidity and mortality

14
Cognitive Assessment

• Not done uniformly
• Dementia is a major predictor of post-op delirium
• Use of Mini-Mental State Exam or orientation and
  recall testing
• Much potential for future research

15
Nutritional Assessment

• Poor nutrition is a risk factor for
• pneumonia
• poor wound-healing
• 30-day mortality
• Hypoalbuminemia (lt3.3mg/dL)
• increased length of stay
• increased rates of readmission
• unfavorable disposition
• increased all-cause mortality

Corti M. Serum albumin level and physical
disability as predictors of mortality in older
persons.JAMA 19942721036.
16
Strategies to Minimize Risk

• Routine screening is low yield
• preop testing should be based on the type of
  surgery
• Manage hypertension
• lower blood pressure to under 180/110
• In patients with dementia, consider placement of
  epidural to control pain without sedation thus
  minimizing risk for delirium
• Avoid long periods without nutrition
• little evidence, but should try to improve
  nutritional status prior to elective surgery

17
Strategies to Minimize Risk

• Perioperative use of ß-blockers
• Mangano, et al., NEJM 1996, RDBPCT
• In patients with or at risk for CAD, does IV
  atenolol decrease periop CV morbidity and
  increase overall survival?
• Cardiac RF included age gt 65, hypertension,
  smoking, cholesterol gt 240, and diabetes.
• 200 pts enrolled IV atenolol 10 mg given 30 min
  prior to surgery, 50-100 mg bid POD 1-7
• 192 followed for 2 yrs

18
Strategies to Minimize Risk
Event-free survival after hospital discharge at 2
years was 68 in the placebo group and 83 in the
atenolol group (p0.008). Not clear yet if age
alone is an indication for use of ß-blockers in
perioperative period.
19
Strategies to Minimize Risk

• Diabetic Postoperative Mortality and Morbidity
  (DIPOM) study
• Perioperative Ischemic Evaluation (POISE) trial
• Metoprolol after Vascular Surgery (MaVS) trial

Http//www.medscape.com/viewarticle/494679
20
Reuben DB, et al. Geriatrics at Your Fingertips
2005, 7th edition. New York, American Geriatrics
Society, 2005.
21
Summary

• Older adults have decreased reserves in multiple
  organ systems.
• Disease burden and functional capacity outweigh
  age when assessing preoperative risk.
• Collaboration among providers helps to identify
  functional, cognitive and nutritional deficits
  and to create management plans to minimize these
  deficits when possible.