Calculations Flashcards
Vd/Vt ratio?
Predict PaO2 by age
Calculate Static Compliance
Calculate Dynamic Compliance
Alveolar Gas Equation
AA Gradient
CO?
HR * SV
Stroke Volume 1?
Stroke Volume 2
EF?
MAP?
Pulse Pressure?
SVR?
O2 Carrying Capacity? (CaO2)
O2 Delivering? (DO2)
Coronary Perfusion Pressure?
Maximum Allowable Blood Loss? (MABL)
Cerebral Perfusion Pressure?
Anion Gap?
Plasma Osmolarity ?
Uncuffed ETT for Children
Cuffed ETT for Children?
O2 remaining in tank?
Fraction of inspired oxygen? (FiO2)
How to calculate Hct?
Hgb x 3
LMA sizes?
Max positive pressure ventilation with mask or LMA?
20 cm H2O
Max cuff pressure in LMA?
40- 60 cm H20
Combitube Sizes
Combitube Pressures
Gas Laws
Universal Gas Laws
Burn Fluid Calculations
Fluid Maintenance
Fluid Deficit Calculations?
of Fasting hours * Maintenance rate
Final Products of Soda Lima
Tank Capacities
SpO2 calculation?
SpO2 Wavelengths?
BP cuff calculations?
What is the transpulmonary pressure?
Pressure inside vs outside the lungs
TPP = Alveolar Pressure - Interpleural pressure
MUST stay positive to keep airways open
Normal Dead Space on an adult?
70kg adult = 150mL
Vd = 2mL * kg
Normal Oxygen consumption ? (VO2)
VO2= CO * (CaO2-CvO2) * 10
Normal
3.5ml/kg/min
250mL/min on a 70kg male
What does it mean when the Oxyhemoglobin Dissociation Curve moves left?
Left = Love
The Hgb wants to hold on to the Oxygen
What causes a left shift on the Oxyhemoglobin Dissociation Curve?
Decrease Temp
Decrease 2,3, DPG
Decrease hydrogen
Alkalosis
Increased pH
Decreased Hydrogen
HgbMet
HgbCO
HgbF
What causes a right shift on the Oxyhemoglobin Dissociation Curve?
Increased everything and acidosis
Increased temp
Increased 2,3 DPG
Increased CO
Increased H
Acidosis
Decreased pH
What is the Bohr affect?
An increased partial pressure of CO2 causes the Hgb to release O2
The Bohr scares the O2 off
Glycolysis creates 1 glucose into?
2 Pyruvic acid
(2 ATP)
How much ATP does the krebs cycle produce?
2 ATP
How much ATP does oxidative phosphorylation (electron transport) create?
34 ATP
How is the majority of CO2 transported in the blood?
Bicarb
What is the Haldane effect?
Describes carriage of CO2.
Oxygen causes the erythrocyte to release CO2
Where in the body is the CO2 Dissociation Curve shifted to the Right? To the Left?
Right - Lungs (so the CO2 is eliminated)
Left - capillaries so the CO2 can be loaded on
What causes a Right shift in the CO2 response curve?
Narcs
Anesthetics
NMB
Sleep
Alkalosis
Carotid Enterectomy
What is the pacemaker of normal breathing?
Dorsal Respiratory Center
Ventral is for exhalation
Pneuomotaxic inhibits the DRC while apneustic stimulates the DRC
Neuro control of breathing?
Medulla
What is the central chemoreceptor stimulated by?
pH changes in the CSF
Can CO2 or H diffuse through the BBB?
CO2 - yes
H - no
What do the peripheral chemo receptors respond to ? Where are they? Which nerve?
PaO2 - increases ventilation when drops below 60
Carotid bodies and aortic arch
Hering’s nerve (glossopharyngeal nerve)
Which surgical procedure impairs the hypoxic ventilatory response?
Carotid enterectomy
Which reflex prevents over breathing?
Hering-Breuer Inflation reflex
Which drugs impair HPV?
Volatile anesthetics > 1.5 MAC
Vasodilators
PDE
Hypervolemia
Excessive PEEP
Which electrolyte abnormality is most likely to occur in acute respiratory acidosis?
Hyperkalemia
What is coronary blood flow equation?
CPP = Aortic DPB - LVEDP
What is the most important determinant of coronary vessel diameter?
Local metabolism
Which part of the myocardium is most prone to ischemia?
LV subendocardium
When are the coronaries perfused?
Diastole
When do most periop MI’s occur?
24-48 hours after surgery and have a 20% mortality
