Exam 3: Obesity Flashcards
(73 cards)
1
Q
What is the #1 cause of medically-related preventable deaths?
A
Smoking
Obesity is #2.
S2
2
Q
Calculation for BMI
A
Kg/m^2
S3
3
Q
Shortcommings of the BMI calculation
A
- Doesn’t differentiate between overweight and overfat
- Doesn’t account for waist circumference, waist-hip ratio or age
S3
4
Q
What is the android body fat distribution, and what is it associated with?
A
- “central” or truncal obsity
- ↑ O₂ consumption
- CV disease
S4
5
Q
Gynecoid body fat distributions are described as ____ obstity around the ____. This shape is ____ metabolically active and not as associated with ____ disease.
A
Gynecoid body fat distributions are described as peripheral obestity around the hips, butt and thighs. This shape is less metabolically active and not as associated with CV disease.
S4
6
Q
Total blood volume is ____ in obesity.
A
increased
because of increased mass
S5
7
Q
Obesity blood volume to weight ratio is typically lower than ____ mL/kg.
A
50 mL/kg
most volume gets distributed to adipose tissue
S5
8
Q
What occurs with cardiac output in obese patients?
A
CO will ↑ by 20-30 mL per kg of excess body fat.
CO increases due to LV dilation and ↑ stroke volume.
S5
9
Q
What causes an increase in cardiac dysrhythmias in the obese patient?
A
- Fatty infiltrates in the conduction system
- CAD
S5
10
Q
What EKG changes are typical of the obese patient?
A
- ↓ QRS voltage
- LV hypertrophy
- Left axis deviation
S5
11
Q
Increased levels of what coagulative factors are noted in obesity?
A
- Fibrinogen
- Factor VII
- Factor VIII
- Von Willebrand
Increased levels = hypercoagulability.
S6
12
Q
Why does endothelial dysfunction occur in the obese patient?
A
Due to ↑ factor VIII and von Willebrand.
S6
13
Q
Gastric ____ and ____ are increased in the obese patient.
A
Gastric volume and acidity are increased.
S7
14
Q
What intubation risk factors are present in an Obese patient due to changes in the GI system?
A
- Delayed gastric emptying
- ↑ chance of gastric volume > 25mL
- ↑ chance of pH < 2.5
The low pH and increased gastric volume increase chance for aspiration pneumonitis
S7
Hepatic function is altered = drug metabolism altered
15
Q
What are the results of increased intragastric pressure secondary to obesity?
A
- LES relaxation
- Hiatal hernia formation (often asymptomatic)
S7
16
Q
Glomerular ____ occurs with obesity due to increased renal blood flow.
A
hyperfiltration
S8
17
Q
What are the consequences of increased renal tubular reabsorption secondary to obesity?
A
- Impaired natriuresis
- RAAS activation = therefore increased systemic BP
S8
18
Q
What are the endocrine effects of obesity?
A
- ↑ SNS activity
- Insulin resistance/impaired glucose metabolism
- Enhanced NE and Angiotensin II activity
- Na⁺ retention (coupled with poor diet contributes to HTN)
- Thyroid hormone resistance = hypothyroidism in 25% of morbidly obese pts
INSET
S9
19
Q
Common diseases seen in association with obesity
A
- Type 2 diabetes mellitus
- Obstructive sleep apnea (side effect of the underlying process)
- Asthma
- Chronic obstructive pulmonary disease
- Hypertension
- Cardiovascular disease
- Cancer
- Osteoarthritis (increased wear/tear on the body bc of increased weight)
D10
20
Q
Metabolic syndrome diagnosis requires 3 of the following:
A
- Abdominal obesity
- ↓ HDL levels
- ↑ Triglycerides
- Hyperinsulinemia
- Glucose intolerance
- Hypertension
- Inflammatory state
- Thrombotic state
S11
21
Q
Risk factors for metabolic syndrome
A
- Increased age
- Men
- Hispanics and South Asians
HIM
S12
22
Q
What drugs may cause metabolic syndrome?
A
- Chronic corticosteroids
- Antidepressants
- Antipsychotics
- Protease inhibitors
S12
23
Q
With metabolic syndrome, pts have an increased risk of
A
- CV disease
- DM2
- PCOS
- Non-ETOH fatty liver disease
- Improper immune responses
98% resolved with bariatric surgery and achieving weight loss goal
S13
24
Q
Differentiate OSA and hypopnea.
A
- OSA: Complete cessation of breathing lasting 10 seconds or more (5 times or more an hour) decreased sat by 4%
- Hypopnea: Airflow reduction by ≥ 50% lasting 10 seconds or more (15 times or more an hour) decreased sat by 4%
S14
25
What is a sleep study called
polysomnography
| S15
26
What would a mild apnea/hypopnea index be?
5 - 15 events/hour
| S15
27
What would a moderate apnea/hypopnea index be?
15 - 30 events/hour
| S15
28
What would a severe apnea/hypopnea index be?
More than 30 events/hour
| S15
29
CPAP is necessary for treatment of moderate or severe OSAHS (Obstructive sleep apnea and hypopnea syndrome) due to risk of what complications?
- Systemic/Pulmonary HTN
- LVH
- Dysrhythmias
- Cognitive impairment
Saul Left Dracula Carefully
| S15
30
What's another name for Obesity Hypoventilation Syndrome?
Pickwickian Syndrome
| S16
31
What causes Pickwickian syndrome?
Long-term OSA
*5-10% of mobidly obese*
| S16
32
What does Pickwickian syndrome cause?
Pulm HTN and Cor Pulmonale
| S16
33
How is Pickwickian syndrome diagnosed?
- > 30 BMI
- Awake hypercapnia
| S16
34
What drug(s) classes are used to treat obesity?
- Phentermine
- Orlistat
- OTC Herbals
- GLP-1 Agonists
| S17
35
How does Phentermine work?
What are it's side effects?
- Sympathomimetic that decreases appetite
- ↑HR, palpitations, HTN, dependence, abuse
| S17
36
How does Orlistat work?
What are the adverse effects associated with it?
- Orlistat blocks absorption of dietary fat
- *do I remember with Dr. T that orlistat is a 5HT3 inhibitor?*
- *Lipase inhibitor, not 5HT3 inhibitor*
- *oh sibutramine is the 5HT3/NE inhibitor...*
- Liquid, fatty stools, urgency, flatulence, cramping and malnourishment.
- Fat soluble vitamin deficiencies
| S17
37
How can Orlistat precipitate coagulopathy?
Possible Vit K deficiency → prolonged PT
| S17
38
Which herbals are pancreatic lipase inhibitors?
Caffeine
Green Tea
| S17
39
How do ginseng, ephedra, and sunflower oil "treat" obesity?
Appetite suppression
| S17
40
What berry is an OTC herbal energy stimulant?
Acai
| S17
41
What OTC Herbals regulate lipid metabolism?
- Soybean Oil
- Fish Oil
- Oolong tea
| S17
42
For patients taking a GLP-1 Agonist on a weekly basis, it is recommended to hold the dose for ____ prior to surgery.
1 week
| S18
43
How would a patient be treated if they forgot to hold their GLP-1 Agonist prior to surgery?
The patient is to be treated as a full stomach or gastric contents need to be evaluated by US.
| S19
44
What to focus on with an obese pt in your preop eval
- HTN
- DM
- HF
- Hypoventilation syndrome or OSA
| S24
45
CPAP pressures usage of > ____ cmH₂O are associated with difficult mask ventilation.
10 cmH₂O
*Corn says to make them very awake for induction and emergence*
| S24
46
Preop eval surgical history things to focus on
| FYI slide
- compare past vs current weight
- ease vs difficult intubations based on past notes
- IV access
- do they need an ICU admission?
- what were the surgical outcomes?
*Even if they have lost weight, they may still have some comorbidities associated with obesity - these pts tend to do poorly with sx (bad wound healing etc)*
| S25
47
Considerations for obese pts going to the OR
| FYI slide
- continue home meds (except antihypertensives, insulin and oral hypoglycemics)
- ABX
- DVT prophylaxis
- Aspiration prophylaxis (pepcid or more)
| S26
48
Ventilation abnormalities we should expect in an obese pt
- decreased VC
- decreased IC
- decreased ERV
- decreased FRV
- low compliance
| S27
49
How does closing capacity compare to tidal breathing in the morbidly obese patient?
Closing capacity ≈ Tidal breathing
*Especially when recumbent/supine - we will see rapid desatting*.
| S27
50
Plan for these things with your intraoperative care of an obese pt
| (FYI and duh)
- **Positioning (can be difficult)**
- Airway management (plan for the worst - glidescope)
- Monitoring
- Choice of anesthetic technique
- Pain control
- Fluid management
| S29
51
What is the most important respiratory/ventilatory intervention that can be done for the obese patient prior to intubation?
**Preoxygenate**.
| Corn
52
Complications of the supine position with an obese pt
- Ventilatory impairment
- Compression of IVC and Aorta
- **Rhabdomyolysis of the gluteal muscles** - leads to renal failure and death
| S30
53
Is prone or lateral decubitus positioning preferred in the obese patient?
Lateral decubitus
| S30
54
What oropharynx change occurs with obesity?
Oropharynx shape becomes elliptical w/ a short transverse and long AP axis.
| S35
55
Increased ____ ____ deposited into the airways can complicate airway management.
Adipose tissue
| S35
56
What is the relationship between degree of obesity and pharyngeal area?
Inverse relationship
*More obese = Less pharyngeal area*.
| S35
57
What predictors of difficult intubation are of particular importance in the obese patient?
- BMI (though not all the time)
- Small mouth opening
- Large Teeth
- Limited neck mobility
- Retrognathia or micrognathia
| S36
58
What axes need to line up for intubation?
Laryngeal, Pharyngeal, and oropharyngeal
*with obese pts, don't just lift up the head, their shoulders need lifting up too and neck extension*
| S37
59
How quickly will a patient with a normal BMI desaturate from 100% to 90% SpO₂?
6 minutes
| Andy
60
How quickly will a patient with a morbidly obese BMI desaturate from 100% to 90% SpO₂?
3 minutes or less
| Andy
61
What is the best positioning on an OR table for recruitment in an obese patient?
1. **30° Reverse Trendelenburg**
2. 25-30° with the head up
| S41
62
What measures should be taken for alveolar recruitment to prevent atelectasis and desaturation in the obese patient?
1. CPAP 10 cmH₂O during preoxygenation
2. Positioning
3. Recruiting maneuvers **then** PEEP 10cm
4. Mechnical ventilation after induction
| S41
63
Which drug classes have exaggerated responses in obese patients (particularly those with OSA) ?
- Opioids
- Benzo's
- Propofol
| S45
64
Which agents are preferred in obese OSA patients?
Short-acting Opioids
- Remifentanil
- Fentanyl
- and α2 agonists…dexmedetomidine
| S45
65
What dose of propofol would you use for induction in an obese pt?
Trick Question: Volatiles are preferred over prop because you have more control - but these pts do hang onto volatiles longer **desflurane is targeted for these pts**
| S45
66
____ is not a favored volatile in obese patients due to their greater O₂ demand.
N₂O
*but Corn likes it because it's off faster*
| S45
67
What drug class (in general) will diminish ventilatory response to CO₂?
Volatile anesthetics
| S45
68
Initial dosing of drugs in obese patients should be based on ____
Lipid solubility of the drug
| S46
69
Which common anesthetic drugs are dosed based on Ideal Body Weight (IBW)?
- Propofol
- Vecuronium
- Rocuronium
- Remifentanil
I PRRV (this is slide 69...Perv)
| S46
70
Ideal Body weight Calculation
| *I have a feeling they may be tricky and ask this....*
Men IBW = 50kg + 2.3 kg for each inch over 5 feet
Women IBW = 45.5 + 2.3 kg for each inch over 5 feet
| Dr. T
71
Which common anesthetic drugs are dosed based on Total Body Weight (IBW)?
- Midazolam
- Succinylcholine
- Cisatracurium
- Fentanyl
- Sufentanil
MS Combs Found Sue
| S46
72
Why do obese pts get cold quicker?
Larger surface area
*be aware of your thermal management*
| S47
73
IV fluids requirements are ____ than what's predicted in order to prevent acute tubular necrosis in the obese patient.
greater
| S48
