Obesity & Its Anesthetic Considerations Flashcards
What percent of the US population is overweight?
50
What percent of the US population is obese?
22
True or false: Obesity is the second most common cause of death in the US
True
Define overweight, obese, and morbidly obese in terms of BMI
BMI > 24 = overweight
BMI 28-35 = obese
BMI > 40 = morbid obesity
List some diseases linked to obesity
Diabetes Coronary heart disease High blood pressure Stroke GERD Arthritis Cancer High cholesterol Endocrine diseases
What is the most common bariatric procedure in Australia and Europe?
Adjustable Gastric banding
What is the most common bariatric procedure in the US?
Roux en Y
What is metabolic syndrome?
The triad of obesity, Hypertension, And type II diabetes
What effect does obesity have on cardiovascular pathophysiology?
It increases the metabolic demand therefore increasing the cardiac output
For every 13.5 kg of fat gained What happens to the vascularization and cardiac output?
2.5 miles of neovascularization occurs
Increased cardiac output of 0.01 L/min for each kg of fat
What should you assess in the cardiac evaluation of an obese patient?
History of prior MI
HTN
Angina
PVD
Which lead looks at the largest amount of muscle mass for the left ventricle?
V5
What is indicative of LVH on EKG?
Peaked R waves
What is the difference in total body water percentage in the average adult versus the severely obese
The adult total body water percentage is 60 to 65%
Severely obese total body water is 40%
How does the estimated blood volume it differ in an obese patient versus a nonobese
Estimated blood volume in an obese patient is 45 to 55 mL/kg actual bodyweight
70 mL/kg for the non-obese
What effect does obesity have on respiratory pathophysiology
Increases CO2 production and oxygen consumption
Obese people are more susceptible to what type of lung disease
Restrictive lung disease
Why is pre-oxygenation so important in obese patients?
Because they have a decreased FRC
FRC is composed of what
FRC = ERV + RV
What is Pickwickian syndrome?
Obesity usually extreme Hypercapnia Polycythemia Hypoxemia Pulmonary hypertension Somnolence OSA
What effects does obesity have G.I. pathophysiology?
Increased risk for aspiration
Increased incidence of GERD and hernias
What are some pharmacological considerations for obese patients?
Increased volume of distribution
Increased GFR
Increased fat stores
What are some anesthetic considerations for induction on an obese patient
Prepare for difficult intubation
Prepare for difficult mask ventilation
Induction may cause airway collapse
Increased risk for aspiration
What is one way to help facilitate intubation on an obese patient
Ramping
What do you always want to have in prior to extubation for an obese patient
Airway!
NAW or OAW
What are the six D’s of a difficult airway?
- Disproportion of tongue size
- Distortion (neck mass)
- Decreased thyromental distance
- Decreased Mouth opening
- Decreased motion of the C-spine
- Dental overbite
What is the best intraoperative position for obese patients
Reverse Trendelenburg
What are two important considerations after extubation of an obese patient
Keep their head up and supply oxygen
