4/12/2010
Consequences
of
Obesity and Respiratory
Respiratory
Health
Obesity
The Medical Update Group
Burrenchobay Hall
University of Mauritius
07.04.2010
Dr H K Makker DM FRCP
Consultant Chest Physician
September 10, 2008
himender@makker.freeserve.co.uk
NAT--CON, New Delhi
NAT
University
y College
g London Hospital
p
1
4/12/2010
Respiratory Consequences of
Obesity
z
20th Century
C t
Fi
Firstt Half
H lf –Respiratory
R
i t
infections/ Tuberculosis
z
20th century second half –smoking related
respiratory diseases –COPD, Lung Cancer
z
21ST Century Respiratory consequences of
obesity
2
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3
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Prevalence of Smoking in
World
4
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Prevalence of Smoking in
England
Prevalence of smoking is declining in England
5
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Prevalence of Smoking in
India
17% of Smokers in the World are in India
30% of men smoke in India
6
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Obesity (Globicity)
z
World -400 Million (WH0 2006)
z
Developed world -7% of Disease burden
(WHO 2002)
Stroke, CHD –33%
z Hypertension –60%
z Western Europe –63% of Heart attacks
z
7
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Prevalence of obesity in the UK
z
Obesity rates (BMI of more than 30 kg/m2)
z
z
z
England
23% and 24%
Scotland
22% and 26%
Wales 17% and 18%
z
Deaths 30,000/year
z
C t NHS 70 billion
Cost
billi
8
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Prevalence of Obesity in the World
Prevalence of obesity is very high in Western World
but also rising in other parts of the world
9
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Prevalence of Obesity in
Mauritius (WHO)
Males
Age
25--74
25
Sample Size (n) Prevalence (%)
1,555
34.7
Females
Age
g
25--74
25
Sample
p Size ((n)Prevalence
)
((%))
1,794
45.6
10
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Obesity--BMI
Obesity
z
W i ht in
Weight
i Kilo
Kil per square meter
t off h
height
i ht
z
z
z
(Weight) kg/ (Height m)2
(75) kg/ (1.75m)2
= 25
BMI (WHO)
z
z
z
z
20-25
2025--Normal
25--30 Overweight
25
30--40 Obese
30
>40 M
Morbidly
bidl obese
b
11
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Obesity –Body Fat
Measurement
z
B d ffatt >30%
Body
30% men, 25% iin women
Sophisticated Tests
z
z
z
z
CT scan
MRI scan
D l energy X
Dual
X--ray absorptiometry
b
ti
t (DXA)
Simple Test
z
z
Skin fold test
Bioelectric impedance analysis
12
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Obesity -Fat distribution
z
A t i l site
Anatomical
it
z
z
z
z
Neck
Chest
Abdomen
Anatomical planes
z
z
Subcutaneous
Visceral
13
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Obesity -Fat distribution
Vi
Visceral
l Abd
Abdominal
i l Obesity
Ob it
(Central Obesity/
Male--type or apple type)
Male
z
Metabolic syndrome
(Insulin resistance)
z
Cardiovascular Risk
Waist (>102 cm in men and >88
cm in women) or
Waist/hip (>0.9 for men and
>0.85 for women)
14
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Respiratory Consequences of
Neck Obesity
Upper Airway Narrowing
Imaging-MRI
Normal
Obese
•Reduction in upper
airway size
size, shape
and volume
•Floppy
15
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Respiratory Consequences of
Thoracic Obesity
Physiological effects
Subcutaneous Fat
Thoracic Compliance (Stiff)
ERV
FRC
VC
Muscle Fat
Weak+ increase in load
16
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Respiratory Consequences of
Abdominal Obesity
Physiological
y
g
Effects
Visceral Fat
Diaphragm
FRC=closing volume
Closure of small airway
Basal atelectasis
V/Q mismatch
Hypoxia
ypo a
Subcutaneous Fat
17
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Respiratory Consequences of
Thoracic and Abdominal
Obesity
P l
Pulmonary
Physiology
Ph i l
Summary
Reduction in FRC
z V/Q mismatch at bases
z Reduced respiratory muscle strength and
endurance
z Increase work of breathing
z
Reduced Pulmonary Reserve
18
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Respiratory Consequences of
Thoracic and Abdominal Obesity
At Rest
Cli i l Features
Clinical
F t
z
Symptoms
z
z
Examination
z
z
z
z
z
Nil
Tachypnoea
yp
Reduced chest wall expansion
Dullness on Percussion at lung bases
Reduced breath sounds at lung bases
CXR
z
Raised diaphragm,
p g , small and g
grey
y lungs,
g , apparent
pp
cardiomegaly
g y
19
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Respiratory Consequences of
Obesity - Exercise
z
High cost of breathing
Breathlessness on exertion
z
z
z
Obese vs. non
non--obese 80% vs. 16% Proportion to BMI
Disproportionately
p p
y high
g if associated COPD and
asthma
Unexplained breathlessness on exertion
z
z
z
No associated respiratory symptoms
Normal cardiocardio-respiratory examination
Mild extraextra-pulmonary restriction.
20
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Respiratory Consequences of
Neck, Thoracic and Abdominal Obesity
Supine
p
z
Upper airways
z
z
upper airway size
Lower airways
z
z
z
FRC
V/Q mismatch
SaO2 (Hypoxia)
21
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Respiratory Consequences of Neck,
Thoracic and Abdominal Obesity
Supine
z
Clinical Consequences
Anaesthesia
z
z
z
z
Induction –Hypoxia (Reduced Pulmonary reserve)
–Pre
Pre--oxygenation
yg
Intubation Difficult/ Failure of Intubation (Narrow
Upper airway)
Extubation /Post
/Post--operative period – Upper airway
obstruction – apnoeas
Prolonged bed rest (fracture, illness)
z
Basal atelectalsis (FRC), Respiratory infections,
Respiratory failure
22
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Respiratory Consequences of
Obesity: Supine +Sleep
z
z
Sleep
Sl
(St
(Stage related)
l t d)
Upper airway
Respiratory drive
z
Apnoea
z
z
z
longer duration,
deeper desaturation
Respiratory rate and tidal volume
z
N t
Nocturnal
lh
hypercapnia
i
23
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24
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Obstructive Sleep Apnoea
z
z
C
Common
– 1-9%
Health Consequences
z
z
z
z
Social consequences
z
z
z
z
Cardiovascular/ Cerebrovascular
Neuropsychological
M t lit
Mortality
Snoring
Excessive daytime sleepiness
R dT
Road
Traffic
ffi Accidents
A id t
Under--diagnosed & Under
Under
Under--treated
25
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GP
Sleep
Clinic
26
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Management of Respiratory
Consequences of Obesity
Obstructive Sleep Apnoea
z
z
z
z
z
Continuous Positive Airway Pressure(CPAP)
Mandibular advancement splint (MAS)
Tracheostomy
Mandibular--Maxillary Advancement
Mandibular
Uvulo--p
Uvulo
palato--pharngoplasty
palato
p
g p
y
27
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Obstructive Sleep Apnoea
Management: CPAP
28
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Management of Respiratory Consequences of
Obesity Obstructive Sleep Apnoea: UPPP
29
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30
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Obesity Hypoventilation
Visilab
z
Case DB–
DB–17.4.44
Pulmonary Function Test
Predicted
FEV1 3.77
FVC 4.70
4 70
TLC 7.30
FRC 3.58
Actual
1.32(35%)
2 08(44%)
2.08(44%)
4.61 (63%)
2.64(73%)
ABG-- p
ABG
pCO2 9.2,, PO2 7.4,, Ph 7.38,, SaO2 87%,, BE –11
31
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Obesity Hypoventilation Syndrome
Pickwickian syndrome
Presentation
z
Non-specific symptoms
Nonz Fatigue, Hypersomnolence, Impaired
Neuropsychological function, Headaches
z
Acute Hypercapnic Respiratory FailureFailureA&E
z Drowsy,
z
confusion, comatose
Chronic Respiratory Failure
z Peripheral
oedema, Pulmonary Hypertension
Cor Pulmonale, CCF
32
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Obesity Hypoventilation Syndrome
Management -BiPAP
Non--invasive Ventilation (NIV) BiPAP
Non
33
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Obesity Hypoventilation
Syndrome
Treatment
Standard Treatment BiPAP
Randomised Trial BiPAP vs CPAP
(Piper AJ.Thorax 2008;63 May)
z Rationale CPAP simpler
simpler, cheaper
cheaper, and easier to
use than BiPAP
z 36 OHS -SaO2>80%, CO2 retention (<10 mm Hg)
z Randomised –either CPAP (18) or BiPAP (18) for
three months
z Both equally effective in improving daytime
hypercapnia
34
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Obesity Hypoventilation Syndrome
Pickwickian syndromesyndrome-Mechanism
OBESITY
25%
OHS (rare)
OSA (1-4%)
Normal
35
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Obesity Hypoventilation Syndrome
Pickwickian syndromesyndrome-Mechanism
Co-factors
Fat Distribution Neck Size
Mandible size and shape
Oestrogen/Testosterone
OSA (1-4%)
+
OBESITY
25%
Normal
36
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Obesity Hypoventilation Syndrome
Pickwickian syndromesyndrome-Mechanism
OBESITY
25%
OHS (rare)
Age
Gender(F)
BMI
PFT (VC)
61 yr
30%
40
79%
OSA (1-4%)
53
10%
32
91%
37
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Obesity Hypoventilation Syndrome
Pickwickian syndrome Mechanism
z
Central Control of Respiratory Drive
(Hypoxic and hypercapnic ventilatory response)
Prader Willi Syndrome
z
z
Most common genetic abnormality –Obesity
Obese PWS vs obese control
z
z
z
Hypercapnic response blunted
Hypoxic ventilatory response –absent
Genetically
y Obese mice ((ob/ob))
z
z
Hypoventilation related to low levels of leptin
Correction of Leptin
z
restoration of ventilatory response to hypercapnia
independent of change in BW
38
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39
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Management of Respiratory
Consequences of Obesity
Weight Reduction
Diet
z Exercise
z Pharmacological (Orlistat, Rimonabent)
z Surgical
z Psychological: Behaviour Modification
z
40
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Outcome of Bariatric Surgery
Meta analysis
analysis--JAMA. 2004;292:1724
2004;292:1724--1737.
z
z
136 Studies,
St di
22,000
22 000 patients
ti t Age
A
39 yr, M:F
M F 1:3
1 3
Outcomes
z
z
z
Weight loss
Operative mortality
Obesity co
co--morbidities
z
z
diabetes,hyperlipidemia,
yp
p
hypertension,
yp
obstructive sleep
p apnea
p
Outcomes
z
z
z
Weight loss 5050-70%
Operative mortality 0.10.1-1%
4 Obesity co
co--morbidities
z Diabetes
resolved
z Hyperlipidemia
improved
z hypertension
resolved
z OSA
resolved
77%
70%
62%
87%
41
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Respiratory Consequences of
Obesity and their management Summaryy
z
Reduced Pulmonary ReserveReserve- Increase
risk of respiratory complication
z
Obstructive Sleep Apnoea –CPAP
z
Obesityy-Hypoventilation
Obesityyp
Syndrome
y
–Acute
and Chronic Hypercapnic Respiratory
Failure-- NIV/BiPAP
Failure
42