Bariatric Flashcards
Overweight BMI
25-29.9
BMI forumula
weight (kg)/height (m^2)
Ideal body weight formula
2.54 cm per inch
height in cm - 100 (men)
height in cm - 105 (women)
Men IBW formula
Height (cm) - 100
Women IBW formula
Height (cm)-105
Calculate the BMI of 440 lb pt that is 5ft 2 inches
81 bmi
hyperinsulinemia pathophys r/t HTN
activates SNS–>Na+ retention–>50-60% increase in incidence of HTN
obesity increases risk of HTN by
50-60%
Closing capacity formula
closing volume + residual volume
relationship at which small airways begin to close
closing volume is
the amount of air in the lungs at which the flow from lower sections of the lungs becomes severely reduced or halts
FRC
reduced due to decreased ERV (FRC = RV +ERV)
ERV
reduced
vital capacity
decreased
total lung capacity
decreased
Decreased FRC is related to
the relationship at which small airways begin to close
Most sensitive indicator of the effect of obesity on pulmonary function
ERV
GA causes FRC to fall by (obesity)
50%
(20% normally)
chronic hypoxemia can lead to (3)
polycythemia
pulmonary HTN
Core pulmanole
Obesity hypoventilation syndrome aka
pickwickian
pickwickian/OHS and resp depressant effeects of anesthesia
increase
RV failure can occur from
hypoxic pulmonary vasoconstriction
Hypopnea
50% reduction in airflow with 4% fall in SaO2–>requires sleep study
Gold standard for OSA diagnosis
Overnight polysomnography (OPS)
Clues to OSA (3)
- BMI >35
- neck circumfrence >16
hyperinsulinemia
elevated glycosylated hemoglobin
STOP BANG
Snoring
Tiredness
Observed stop breathing
Pressure
BMI >35
Age
Neck circum >40
Gender male
> 3 questions yes = high risk for OSA
hypertrophy in obesity
Eccentric
ECG changes
-.Low QRS voltage
-LVH criteria
-left atrial enlargement
-t wave flattening inferior and lateral leads
-prolonged QT interval
Portal triad clamping - mechanism and why
TO reduce blood loss
hepatic artery
portal vein
Common bile duct
WIth previou bariatric surgery, what happens with mebranes
premature rupture of membranes (pregnancy)
Lean body weight on induction
Propofol
Roc
Vec
Remifent
Lean body weight maintancance
Roc
Vec
Remifent
Sufent
fent
total body water obesity
decreased
IV drug delivery obesity
higher CO–>shorter drug circulation time and faster delivery to site of action
good predictors of difficult intubation
BMI with Mallampati >3 with a large neck circumference* and history OSA
Cricoid pressure position
Below thyroid cartiladge, above cricoid cartiladge
FiO2
preoxygenate 100% for 3-5 min
intraop: 50%-80%
PEEP
10-12
TV
6-8 mL/kg iBW
PaCO2 intraop
40-45 (permissive hypercapnia OK)
only parameter that has consistently shown improved rspiraty funciton is
PEEP! up to 10 cm H2O
Fluids should be calculated by
lean body weight
ideal body weight x 1.3
Least invasive bariatric procedsure
restrictive (laprascopic sleeve gastrectomy or gastric. band)
Most common cause of surgical related mortality in obese patients
Anastomotic leak
Top 3 symptoms of anastomotic leak
- tachycardia
- fever
- abdominal/pelvic pain
also SOB, restlessness, L soulder pain, increased thirst, hypotension