Obesity Flashcards
What is phentermine?
A weight-loss drug (appetite suppressant) that some patients may be on
How is obesity defined?
Weighing 20% more than your ideal body weight
or
BMI > 30 kg/m2
A BMI > ____ is associated with morbidity due to stroke, ischemic heart disease, DM, and certain cancers
30
Obese people have a high incidence of ____ within 30 days of surgery.
PE
More likely to die from it if BMI > 40
New research suggests SQ heparin for 3 weeks after surgery
NPO status for obese patients
Need to be NPO for a longer period of time because they have delayed gastric emptying, increased gastric volume, and lower gastric pH
4 major risk factors for post-op PE
BMI > 30, truncal obesity, venous stasis disease, and OSA or OHS (obesity hypoventilation syndrome)
Respiratory conditions associated with obesity
OSA/OHS
Restrictive lung disease
Pulmonary HTN
CV conditions associated with obesity
HTN Cardiomegaly Ischemic heart disease Cerebrovascular disease PVD DVT HLD Sudden death
Endocrine conditions associated with obesity
DM
Hypothyroidism
Cushing Syndrome
Musculoskeletal conditions associated with obesity
Arthritis of weight bearing joints
Back pain
Malignancies conditions associated with obesity
Colorectal Breast Prostate Uterine Cervical
Resp volume changes associated with obesity
Decreased FRC, ERV, and TV. TV may fall into the range of the closing capacity (cc).
RV is unchanged.
What is closing capacity?
The volume in the lungs at which the alveoli collapse
Obese people should be put to sleep in this position
Reverse-T
What effect does the decreased expiratory reserve volume have?
Faster closure of small airways
What should we try to avoid giving to obese patients?
Muscle relaxants. They do not have a long safe apnea time.
Minute ventilation for obese pts are higher/lower than normal
Higher. Remember that obese people have increased oxygen consumption and CO2 production due to increased body mass/tissue.
Do we want to get PFTs on obese pts?
Not usually.
Changes in PFTs don’t occur until the obesity worsens to the point where they have restrictive lung disease of pulmonary HTN.
What test of pulmonary function do we normally want to get on the obese?
ABG
What will happen if an obese pt has anesthesia induced in the supine position?
Rapid desaturation***
All obese patients should have these on during the case to prevent PE
TEDs and SCDs
Why do obese patients have more strain on their hearts?
Increased CO and expanded blood volume (more tissue). Also, if OSA is present, can cause polycythemia, and increased blood viscosity.
Obese patients have limited reserve for
Hypotension
HTN
Tachycardia
Fluid overload
HLD associated with obesity can lead to
Atherosclerosis -> premature CAD and PVD.
Pancreatitis.