Transcript Surgery in the Elderly

The Anaesthetic Assessment of
an Elderly Surgical Patient
Dr. Irwin Foo
Consultant Anaesthetist and Honorary
Clinical Senior Lecturer
Department of Anaesthesia
Western General Hospital
Edinburgh
Scope of the lecture
• Anaesthetic definition of elderly and
workload
• How elderly patients differ from younger
counterparts
• The current state of affairs and why there is
room for improvement
• Importance of good anaesthetic assessment
• Concept of functional reserve/capacity
• Perioperative management
Anaesthetic Definition of ‘Elderly’
• AAGBI document (2001)
– > 80 yrs = elderly
– Physiological changes/functional decline
most marked after 80 years
• Chronological vs biological age
– Chronological age - poor discriminator of
individual surgical risk
– ‘old’ 60 yr old vs ‘young’ 80 yr old
– Heterogenecity - most consistent feature
in the elderly population
Variability of organ function with age
% ORGAN FUNCTION
100
80
‘YOUNG’
60
‘AVERAGE’
40
20
‘OLD’
0
20
30
40
50
60
AGE (YEARS)
70
80
90
Size of the problem
• Increasing numbers
– > 80’s -fastest growing section of the
population
– 2005- >20% of population 65 yrs and
over
• increasing workload
– 50% of elderly will require anaesthesia
for surgical intervention in their lifetime
– surgical/anaesthetic advances
Anaesthetic/Surgical Workload in the
Elderly Population
(%)
26
24
22
20
18
16
14
12
10
Anaesthetised
population
Resident
population
85 86 87 88 89 90 91 92 93 94 (YEAR)
Klopfenstein CE et al. Anesth Analg 1998; 86:1165-70
How do elderly surgical patients
differ from younger counterparts ?
• Anaesthetising the elderly……….
• “Applied clinical pharmacology
with enough patho-physiology
included to confuse the picture”
Comorbidity in the elderly
• Increasing medical conditions with age
No
preoperative
problems
(20%)
% of
patients
60
50
40
30
20
10
0
n = 288
CVS
RS
Vaz FG et al. Age and Ageing 1989; 18: 309-315
CNS
Extent of surgical stress
(patients > 90 yrs; n = 301)
Type of
surgery
Mortality after
2 days (%)
Mortality after
30 days (%)
Major vascular
20.0
20.0
Thoracotomy
12.5
37.5
Biliary, liver
6.7
26.7
Bowel, rectal, anal
3.8
23.8
Hip
TURP, eye
2.7
0.0
8.2
0.0
Warner et al, Ann Surg 1988; 207: 380 -386
Variable physiological ageing in the
elderly
% ORGAN FUNCTION
100
80
‘YOUNG’
60
‘AVERAGE’
40
20
‘OLD’
0
20
30
40
50
60
AGE (YEARS)
70
80
90
The main risk factors determining
outcome in the elderly
• Severity of co-existing disease
• Surgical procedure
• Physiological age
How are we doing?
The Good News…………
Outcome of Anaesthesia and Surgery in
people > 100yrs and older
Warner et al JAGS 1998; 46:988
• Retrospective study
• n = 31 (100-107yrs)
• GA 39% RA 35%
Sedation 26%
• 1 major complication
within 48hrs
• Mortality rates
– 48hrs 0%
– 30 day 16%
– 1 year 36%
The Bad News……….
Highest incidence of mortality and
morbidity- NCEPOD data
Remained constant despite advances
in anaesthesia/surgical techniques
• NCEPOD 1998/1999 -
Likely Explanations
• British surgical patients have on average a
worse ASA status than 10yrs ago
• ASA Physical Status categories:
• Class 1: a normally healthy patient
• Class 2: patient with mild systemic disease
• Class 3: patient with moderate to severe
disease that is not incapacitating
• Class 4: patient with incapacitating disease
that is a constant threat to life
• Class 5: moribund patient- not expected to
survive 24 hrs with or without an
operation
Likely Explanations
• 9 out of 10 patients aged > 60yrs
receiving GA have ASA status of 2 and
over
• 21% > 65yrs developed one or more inhospital postoperative complications
Relevance of postoperative
complications
• Hospital postoperative complications
shortens long-term survival (Manku et al,
2003)
– 7 x  risk in the first 3 months after surgery
•
(3 x without complications)
– In-hospital risk factors:- pulmonary and renal
complications
– Other factors:- history of cancer, ASA>II, age,
history of neurological disease
Hospital postoperative complications
shorten long-term survival
Relative risk of mortality:
0-3 months
No complications
2.9
(1.8-4.6)
With complications
Age > 80 yrs
No complications
7.3
(3.8-14)
1.7
(0.8-3.8)
With complications
6.2
(2.6-14.9)
3-12 months > 12 months
1.3
2.3
(1.04-1.7)
(1.7-3.2)
2.4
(1.2-4.6)
1.9
(1.2-3.1)
1.6
(0.98-2.5)
2.4
(1.06-5.3)
1.1
(0.84-1.6)
2.1
(1.2-3.6)
Room for improvement?
NCEPOD report- extremes of ages
1999
Recommendations
• lack of senior multidisciplinary care
• poor fluid management
• matching of experience of
surgeon/anaesthetist to physical status
of elderly patient
• Appropriate postoperative care
• Effective pain management
Scottish Audit of Surgical Mortality
- Case Assessments Booklet - 2004
• Four hourly bags of iv fluids can
drown an elderly patient
• Elderly patients have limited
physiological reserve
• Cardiovascular collapse during
orthopaedic surgery
• Unnecessary laparotomy on elderly
patient
How we can improve the management
of the elderly surgical patient ?
• Adequate anaesthetic assessment
• identification of failing integrated responses/functional
reserve of individual organs
• plan appropriate anaesthetic technique
• Optimisation preoperatively –
multidisciplinary approach
• Estimate likely outcome of proposed surgery
(alter if necessary)
• ? day or inpatient surgery
• Postoperative placement
Preoperative Assessment
• Assessment of damaging effects of
concurrent medical conditions
• Influence of normal ageing processes
• Functional reserve/capacity
assessment: both intergrated and
individual organs
• Specific elderly issues e.g.
postoperative cognitive dysfunction
(POCD)
The effects of ageing
• Progressive loss of functional reserve in all
integrated and single organ systems
• Invisible loss until 70-80% loss of reserve
has occurred
• Anaesthesia/surgical insult often utilises
50% or more of functional reserve
% Maximal Organ Function
100
80
Maximal
Functional
Reserve
60
40
20
0
Basal
20
30
40
50
60
70
80
90
The effects of ageing
• Clinical signs of failure in any organ system
indicates complete loss of functional reserve
• Confusion/delirium developing
postoperatively suggests poor cognitive
reserve
• Preoperative assessment aim is to identify
systems at risk of failure and to try and
minimise risk (if possible)
Traditional diagnostic approach
History of presenting illness
Medical/Surgical history
Physical examination
Investigations
Diagnosis and Mx plan
CNS
CVS
RS
GI
UGS
Immune
system
Organ-system based approach for preoperative
assessment
Medical and surgical history
Activity level and quality
Physical examination
Investigations
Assessment of organ system reserve
CNS
CVS
RS
GI
UGS
Immune
system
Brief reminder of age-related
changes
Age-related cardiovascular changes
• Reduced autonomic responsiveness
• SNS activity ;Parasympathetic 
• Baroreceptor reflex activity 
• -adrenoceptor responsiveness 
• Decreased maximum heart rate
• Frank-Starling mechanism- major
mechanism for maintaining stroke volume
Priebe H-J. BJA 2000; 85:763 - 78
Age-related cardiovascular changes
• Increased vascular stiffness
–  systolic BP
– widening of pulse pressure
• Left ventricular wall thickening
–  compliance: impairment of diastolic
function
• Greater dependence on atrial function for
ventricular filling
– contribute up to 30% of SV
Priebe H-J. BJA 2000; 85:763 - 78
Age-related respiratory changes
•  Vital capacity /  Residual volume
•
•
•
•
 strength and mobility of muscles
lung elastic recoil 
chest wall compliance 
spinal collapse (anterior wedging)
•  closing volume/capacity
•  V/Q abnormalities →  gas
exchange
Effect of age on closing capacity and
FRC
Lung volume (L)
3
FRC, upright
FRC, supine
2
1
0
30
40
50
60
70
Age (years)
Postoperative PaO2 in the Elderly
Postoperative PaO2 (mmHg)
160
140
120
Oxygen by facemask
100
80
60
No Oxygen supplement
40
20
0
20
30
40
50
60
Patients with no preexisting pulmonary disease
70
80
Age (years)
Age-related respiratory changes
•  hypoxic and hypercapnic reflex
control
• Poor upper airway tone
– snoring almost universal
• Poor cough (7 fold reduction in
sensitivity of cough reflex)
•  risk of aspiration (silent!!)
• Chest wall rigidity  more dependent
on the diaphragm
Age-related neurological changes
•  brain cell mass (10-30% by age 80)
– loss of central cholinergic and
dopaminergic cells
– 70-80% loss of dopaminergic function
required before symptoms seen in
Parkinson’s disease
– ‘Crystallised’ intelligence better
preserved than ‘liquid’ intelligence
• Poor reflex control
– baroreceptor , thermoregulation
Age-related neurological changes
• Blindness
– cataracts, glaucoma
– problem with visual analogue scales
• Deafness
– problems with comprehension
– may be denied by patient
• Cognitive impairment
– dementia present in 22% of over 80’s
– (life expectancy-50% in 5yrs)
Age-related hepatic changes
•  liver mass and blood flow
– 1% loss/yr after 30 yrs
– minor changes in cytochrome P450
activity
– variable effect on Phase I reactions;
Phase II not affected
• Drugs which are flow-limited affected
greater than capacity limited
– lignocaine/bupivacaine, opioids
• Reduced albumin: altered drug binding
Age-related renal changes
• Marked decline in RBF and GFR (1% loss of
function/yr after 30yrs)
• Plasma creatinine: not good guide of renal
function bec. of reduced muscle mass
• Response to Na concn impaired; less able to
excrete Na load
• Reduced ability to dilute/concentrate urine
–  thirst perception
– fear of incontinence
– locomotor problems-inability to get to fluids
Age-related musculoskeletal
changes
• Osteoarthritis/Osteoporosis
– immobile   venous stagnation
– limits ability to exercise
• Poor stability/balance
–  risk of accidents esp. in unfamiliar
surroundings
• Ligamental laxity
– cervical vertebrae slip
Functional Reserve/Capacity
Assessment
Integrated functional reserve
• Metabolic equivalence
– attempt to quantify metabolic (O2 delivery)
capacity of the patient
– estimates the likely outcome of surgery
– predicts the likelihood of postoperative
complications
• patients unable to reach 4 METS
Examples of metabolic equivalents
Score
Activity
1
Eat and dress, walk indoors
around the house
2
Walk a block on the level, do
light work around the house
4
Climb a flight of stairs or walk
uphill, heavy domestic work, run
a short distance
6
Moderate recreational activities
e.g. dancing, golf, doubles tennis
10 Strenuous sports e.g. swimming
Integrated functional reserve
• METS-dependent on patient history
• McGlade et al. Anaesth Intensive Care
2001; 29:520-6
– compared reliability of patients as historians
– used a questionnaire and a simple exercise
test
– 14% of patients who claimed they could climb
a flight of stairs declined to do so
• watching them climb a flight of stairs more
reliable
Cardiopulmonary Exercise Testing in
elderly patients undergoing major
surgery
Older et al. Chest 1999;116:355-62
CPX testing: gold standard for
identifying high-risk patients
• bicycle ergometer/
metabolic cart
– computerised analysis of
gas exchange data/ 12 lead
ECG data
– anaerobic threshold (AT)
– AT < 11ml/min/kg
equivalent to less than 4
METs
CPX testing:as screening test for
perioperative management
CPX testing: gold standard for
identifying high-risk patients?
• excellent predictor of mortality from
cardiopulmonary causes postop
– allows appropriate placement
• good safety record
• Drawbacks
– requires up to 1hr per patient
– not all elderly patients can perform test
Functional reserve of individual organs
• Cardiac assessment– ECG most useful
– abnormality in up to 60%
– asymptomatic systolic murmur require
further investigation: NCEPOD 2001
• aortic valve sclerosis: 48%;
• calcific aortic valve stenosis: 4%
– Normal systolic cardiac failure
• disorder of the elderly
• ? role of brain natriuretic peptide in Dx
Guidelines for Preoperative Resting
Echocardiography
• Previous CCF or MI with a reduction in
functional capacity (< 4 METS)
• Dyspnoea not explicable by pulmonary disease
(on PFTs) or obesity, with an abnormal ECG
• Cardiac murmur with one or more factors below
•
•
•
•
•
•
•
Reduced functional capacity (< 4 METS)
Chest pain
Orthopnoea
PND
Peripheral oedema
Cardiomegaly (on CXR)
Abnormal ECG (arrhythmia, conduction defect, LVH)
Functional reserve of individual organs
• Respiratory assessment– Pulse oximetry on air (lying and standing)
– Hx of snoring should be actively sought
• Renal assessment– use Cockcroft Gault Formula
• converts serum creatinine to creatinine clearance
– CC (ml/min) =(140 - age) x wt (kg) x (1.04 for )llllllllllll
creatinine (μmol/l)
• 88yr old female for colectomy, weighing 40kg with a
serum creatinine of 100 μmol/l.
• Calculated creatinine clearance = 21.6 mls/min
Functional reserve of individual organs
• Neurological assessment – delirium (acute confusional state) is an
independent predictor of adverse
outcomes in older hospital patients
• prolonged hospital stay
• functional decline
•  risk of developing hospital-acquired
complication
– Incidence of postoperative delirium: 1020%
Delirium
• Hx of previous postoperative delirium
indicates incipient brain failure
– ?avoid general anaesthesia/sedation
• Preoperative tests recommended
– AMT
– MMSE
• Serial testing using the AMT useful
– abrupt decline of 2 or more points =
sensitive/specific indicator of delirium
Abbreviated mental test
Age
Time (to the nearest hour)
Address - to recall at the end of the test:
42 West Street (ask patient to repeat the address
to ensure it has been heard correctly)
Year
Name of hospital
Recognition of two persons (e.g. doctor, nurse)
Date of birth
Year of start of the first world war
Name of monarch
Count downwards from 20 to 1
Causes of delirium
•
•
•
•
•
•
•
•
•
•
medications
medications
medications
infection
hypoxia
pain
congestive heart failure
metabolic problems
some combination
something else
Neurological assessment
• If AMT abnormal  MMSE
– dementia likely if score less than 25
– diagnosis of dementia should not be made
lightly (involve care of the elderly)
– Issue of consent: Adult with Incapacity
Act 2000
• Cerebrovascular disease of the
vertebral arteries
• flexion/extension of the neck during
intubation
• test: looking up from sitting position without
feeling dizzy
Laboratory investigations
• Blanket routine preoperative
investigations are inefficient, expensive
and unnecessary
– AAGBI working party publication (2001)
– Age per se is not an indication for
preoperative testing
– Guided by history, clinical examination and
proposed surgery
• NICE guidelines (2003)
Optimisation preoperatively
• Multidisciplinary team approach
– care of the elderly
• mental state
• endocrine
• polypharmacy issues
– cardiology
• murmurs (aortic stenosis)
• intractable cardiac failure
– physiotherapists, nutritionists
Outcome assessment and placement
• Inherent risk of operation
– size of stress response
– is it appropriate surgery?
• matching of experience of
surgeon/anaesthetist to physical status
of elderly patient
• Plan appropriate anaesthetic technique
• Appropriate postoperative care
– ward/HDU/ICU
Day or inpatient surgery?
• Minimises disorientation and stress for the
patient
– Social support must be in place
• Outpatient surgery reduce postoperative
cognitive dysfunction (ISPOCD2 group)
– n = 372; > 60 yrs; no restriction on type of
anaesthetic/analgesia used
– POCD = inpatient: 9.8%; outpatient: 3.5% at 7
days
– Risk factors: age > 70yrs and in vs outpatient
surgery
Preoperative management
• Premedication
– avoid if possible
– no benzodiazepines (esp. diazepam), centrally
active anticholinergics and intramuscular drugs
– avoid pethidine
• Give all regular medications
– including nicotine patches +/- alcohol
• Preoperative fluids (bowel prep)
• Maintain dignity- dentures to remain in
place
Postoperative cognitive deficit (POCD)
• Complex clinical picture that includes
–
–
–
–
disorientation
delirium
dementia
personality changes
• Incidence of POCD - ISPOCD 1 (1998)
–
–
–
–
1100 patients over 60yrs
25.8% deficit at 1 week
9.9% deficit at 3 months
(still 10% at 2yrs)
Postoperative cognitive deficit (POCD)
• Causes of POCD
– Not hypoxia or hypotension
– Not general anaesthesia (ISPOCD 22003) but lab studies: ↑ ß-amyloid
deposition with volatile anaesthetics
– Stress response to surgery
• prolonged hypercortisolaemia
• central catecholamine changes
– Decline in central cholinergic function
– Genetic predisposition (APOE gene) –
negative studies
Futility
• Inappropriate procedure with no
benefit in longevity
– heroic surgical therapy
– ‘senior’ decision to operate
• Palliative surgery must be provided for
symptomatic relief
Case study 1
• 82 yrs
• Scheduled for paraumbilical
hernia repair (laparotomy 15 yrs
ago for small bowel obstruction)
• Preoperative cardiac murmur
and 2 episodes of dizziness
• ECHO- critical aortic stenosis
and moderately impaired LV
• Intermittent abdominal pain
from hernia site
Case study 2
• 72yrs
• Hartmann’s procedure for
perforated diverticular disease 1yr
ago
• ‘Not quite the same - poor
concentration, tends to get
confused and more withdrawn
• Requesting reversal of Hartmanns
as ‘cannot cope with bag’
To sum up………….
Young
Elderly