Exam 1: Obesity

Question 1

BMI for obese, morbidly obese, and super-obese:

Answer 1

30+
40+
50+

Question 2

WHO obesity classes and BMIs:

Answer 2

Class I: 30-34.9
Class II: 35-39.9
Class II: 40+

Question 3

Four post-op DVT risk factors:

Answer 3

Venous stasis
BMI 60+
Truncal obesity
OSA/OHVS

Question 4

Lung volume changes in obesity:

Answer 4

Decreased FRC
Decreased ERV
TV approaching closing capacity

Question 5

Sequelae of decreased FRC r/t induction:

Answer 5

Less safe apnea time

Question 6

Respiratory changes in ventilation:

Answer 6

Increased O2 consumption, CO2 production

High MV d/t inc RR

Dec chest wall compliance

Inc respiratory resistance/restrictive lung disease

Question 7

PFT changes in obesity:

Answer 7

May remain normal until lung disease advances/pulmonary hypertension starts

Question 8

Troublesome positions for obese pts:

Answer 8

Supine
Trendelenberg
Prone

Question 9

% intubation difficulty at neck circumference of 40cm and 60cm:

Answer 9

5% and 35%

Question 10

CO increases by ______ per each ______ of adipose tissue:

Answer 10

.01L/min per KG

Question 11

Arterial HTN and CAD risk is _____ in obese pts:

Answer 11

Doubled

Question 12

How does obesity lead to RH failure?

Answer 12

Increased blood volume and OSA/OHS leads to pulmonary hypertension

Increased CO and PHTN leads to increased RV workload and hypertrophy

Question 13

How does obesity lead to LH failure?

Answer 13

Increased CO leads to increased LV workload,

Which, along with systemic HTN, leads to LV hypertrophy

Which, along with CAD, leads to LV failure

Question 14

OSA characterized by:

Answer 14

Apnea > 10 seconds despite repiratory effort

Hypopnea episodes resulting in 4%+ drop in arterial O2

Question 15

Mild/moderate/severe OSA:

Answer 15

Mild: 5-14 episodes/hr
Moderate: 15-30
Severe: 31+

Question 16

OSA risk factors:

Answer 16

Middle age
Male
Obese
ETOH use
Drug sleep aids
Abdominal fat
Neck girth (16+ women, 17+ men)

Question 17

Another name for obesity hypoventilation syndrome:

Answer 17

Pickwickian syndrome

Question 18

OHS characterized by:

Answer 18

Loss of hypercarbic drive due to progressive desensitization of respiratory centers to nocturnal hypercarbia

Sudden death during sleep

Question 19

GI effects of obesity:

Answer 19

GERD
Hiatal hernia
Increased gastric volume
Increased intragastric pressure
Increased gastric acidity

Question 20

Thromboembolic effects of obesity:

Answer 20

DVT risk doubled
Polycythemia
Increased intra-abdominal pressure
Immobility

Question 21

Gastric risk factors for aspiration pneumonitis:

Answer 21

Volumes > 25ml

pH < 2.5

Question 22

Hepatic effects of obesity:

Answer 22

Fatty liver

Abnormal LFTs

Question 23

Metabolic effects of obesity:

Answer 23

Insulin resistance

Adult onset DM

Question 24

A fasting BG above _____ is a problem pre-op.

Answer 24

200

Question 25

Reglan is contraindicated in what condition?

Answer 25

Bowel obstruction

Question 26

What can reverse elevated LFTs due to obesity?

Answer 26

Weight loss

Question 27

How do obesity-related elevatd LFTs affect clearance?

Answer 27

Normal clearance

Question 28

Pre-op labs for obesity:

Answer 28

LFTs
Albumin level
Glucose
Clotting studies if risk factors

Question 29

What position provides the longest safe apnea period for the obese pt?

Answer 29

Head-up Trendelenberg

Question 30

Prone position for obese patients has these effects:

Answer 30

Increases intra-abd pressure
Worsens caval/aortic compression
Decreases FRC further

Question 31

Aspiration prophylaxis for obese pts:

Answer 31

H2 antagonists
Bicitra
Reglan
Omeprazole