Obesity Flashcards
What BMI is considered being overweight?
What BMI is considered being obese?
What BMI is considered morbidly obese?
BMI > 30
BMI > 30 -35
BMI > 40
Obesity is considered being greater than ____% ideal body weight.
20%
What is the waist size (M/F) for an obese person?
40 male /35 female
Morbidly obese is ___ times ideal body weight.
2
What diseases are linked to obesity? (10)
- diabetes
- heart disease
- HTN
- stroke
- arthritis
- GERD
- cancer (endometrial, breast, prostate, colon)
- high cholesterol
- endocrine disease
- REDUCED FERTILITY
What are the types of bariatric surgeries?
gastric restriction (AKA gastroplasty)
adjustable gastric banding
gastric restriction with bypass
This is known as:
gastric restriction, gastroplasty
What type of gastric restriction is this?
adjustable gastric banding
Gastric restriction, both methods, decrease stomach contents by how much?
10-20 cc
What is the most common bariatric procedure in Australia and Europe?
adjustable banding
Which method is associated with a decreased rate of weight loss?
adjustable banding
What is the most common bariatric procedure in the US?
gastric bypass
What type of gastric surgery is this?
What is the extension limb called?
gastric bypass
Roux limb varies between 75-150 cm
A shorter Roux limb results in greater weight loss. True or false?
false, longer one
What is the gold standard of weight loss surgery?
bypass
What is the “metabolic syndrome”?
Triad of:
Obesity
HTN
Type II DM
Excess body mass leads to what regarding metabolic demand and cardiac output?
Increased metabolic demand
Increased CO
What is a result of increased CO with respect to workload and pulmonary flow?
Increased workload leading to LVH
Pulmonary HTN → Cor Pulmonale → right heart failure
in short, increases pulmonary flow
What are cardiovascular issues that may result from obesity? (5)
Increased risk of arrhythmias
Hypertrophy
Hypoxemia
Fatty infiltration of conduction system
Increased catecholamines
How much CO is needed for each kg of fat? (L/min)
0.01 L/min
During cardiac evaluation of obese pt, assess for: (4)
prior MI
HTN
angina
PVD
Sudden cardiac death is more prevalent with: (2)
LVH
ventricular ectopy
What do you need to evaluate in EKG for obese patients? (2)
axis deviation
atrial tachyarrhythmias
What does this strip indicate?
LVH in lead V5
Severely obese total body water is ____ %.
Estimated blood volume in obese patient is about ____ mL/kg of actual body weight.
40%
50 mL/kg
What do you consider when replacing fluid in an obese patient?
avoid rapid rehydration
hetastarch at ideal body weight
albumin 5-25% as indicated
crystalloid for blood loss 3:1
What are the respiratory consequences of obesity?
Increased CO2 production
Increased O2 consumption
In obese patients, treat like they have restrictive lung disease. As a result, you may be encountered with these issues:
decreased chest wall compliance
diaphragm forced cephalad
decreased lung volumes
FRC may fall below closing capacity resulting in alveolar collapse and V/Q mismatch
What is the Desaturation Theory?
FRC is reduced by 1.5 L with changing body position.
If BMI > 43, time to desaturate is < ____ minutes.
2
What is the primary source of oxygen reserve during apnea?
expiratory reserve volume
What changes will be affected from least to greatest in pulmonary function tests?
tidal volume
inspiratory reserve volume
expiratory reserve volume greatly reduced
What is obesity-hypoventilation called?
Pickwickian syndrome
What are the consequences of Pickwickian syndrome?
hypercapnia
cyanotic from hypoxemia
polycythemia
pulmonary HTN
somnolence
sleep apnea OSA
biventricular failure
What are GI concerns for obese patients? (4)
SEVERE RISK OF ASPIRATION
GERD
hiatal hernia
increased abdominal pressure
What is the best treatment for obese patients regarding GI issues?
pre-op with H2 blockers night before surgery!
What are pharmacological considerations for obese patients?
increased volume distribution
increased GFR and clearance of untransformed drugs
increased requirements
Des results in quicker wake up than Sevo. True or false?
false
Since increased volume of distribution in obese patient, what will we do as a result for our induction anesthetics?
give larger loading dose and less frequent maintenance dose
What drugs do we dose on ideal body weight and why?
rocuronium
water soluble
What drugs do we dose on total body weight and why?
propofol, except on induction (use IBW)
Sux
Versed but will cause somnolence
To decrease the risk of aspiration pneumonitis, consider what 2 drugs?
H2 antagonist
metoclopramide
Difficult ventilation will be attributable to what factors?
age > 55
snoring
lack of teeth
BMI > 26
Important induction airway equipment not to forget:
glidescope
nasal trumpet
introducer
What are the 6 D’s of difficult airways?
Disproportion
Distortion
Decreased thyromental distance
Decreased inter-incisor (mouth opening distance)
Decreased ROM
Dental overbite
When will we need higher FiO2 with regards to positioning in obese pts?
trendelenberg
lithotomy
prone
What is the best intraoperative position for an obese patient?
reverse trendelenberg
