anesthesia final1
Terms
copy deck
 how many psig = 1 atm
 14.7 psig = 1 atm
 1 mmHg = ?? mmH2O
 13.6 mm H2O
 What is the formula for flow:
 F = Q/t
 What is Poiseulle's Law?
 Q=(pi)(P)(d)^4 / 128 n l
 What part of Poiseulle's Law has the greatest effect on flow:
 diameter (it is to the 4th power)
 What is Laplace's Law

pressure gradient across wall of a TUBE = tension/radius
P=t/r  What is Laplace's Law equation for a sphere:
 P = 2t/r
 What is the formula to describe how surfactant affects Laplace's Law?

P = r/ 2t
surfactant reverses Laplaces Law.  Describe flow through a venturi:
 as gas moves throuhg the constriction it creates a change in potential energy to KINETIC energy and with it a huge drop in pressure (subatmospheric) and can be used to entrain air/gas into the system.
 Is the opening of a thorpe tube at LOW flow orificial or tubular, laminar/turbulent? Which quality of the gas is most important in determining flow?
 At low flows the flow is laminar and the opening is tubular. Density is the quality that will most affect flow.
 At high flows via flowmeter is the opening orificial/tubular and is flow laminar/turbulent? Which quality of the gas will most determine flow characteristics?
 At high flow the opening is orificial and flow is turbulent. Viscosity is the key quality that will determine flow.
 Boyles Law:
 at constant temp, pressure and vol are INVERSELY related
 Charles Law:
 at constant pressure, temp and vol are directly related
 Gay Lusac's Law:
 at constant vol, temp and pressure are directly related
 What is the combined gas law:
 P1 V1/ T1 = P2 V2/ T2
 What is Daltons Law of partial pressures

(P)total = P1 + P2 + ....
in a mix of gasses., the partial pressure exerted by each gas is the same as it would exert if it were alone in the container.  What is Avogadros hypoth
 equal volumes of gas at same temp and press have the same # molecules
 What is avogadros #
 6.022 x 10 ^23
 1 mole of a gas at stp will take up what vol?
 22.4L
 Henry's Law:
 at a given temp, the amount of gas dissolved in a liq is directly proportional to the partial pressure of the gas in equilibrium with the liq.
 How does a gas' sol coeff affect it's alveolar partial pressure?
 The lower the solubility, the faster it will develop a high alveolar pressure gradient and hence will have a faster onset of action. This is based on Ficks Law which says that the rate of diffusion will increase as the conc gradient increases.
 Grahms Law:
 the rate of diffusion of a gas is inversely related to the square of it's molec wt
 What is a 1 Normal solution:
 1 GAW/GMW of (nonionized)subst in 1 L of water.
 Raoults Law:
 the depression or reductin in vapour pressure of a *solvent is proportional to the molar conc of the *solute
 How much time do you have left on an Ecylinder of O2 if the gauge reads 700 psig and you're flowing gas at 4LPM?
 Just over an hour, +/ 61 min.
 What is the definition of partition coefficient:
 the ratio of a substance in two phases at equilibrium.
 Is the "failsafe valve" on an Ohmeda machine really foolproof in protecting the pt from a hypoxic mixture of gas?
 No. It merely ensures that the O2 system is pressurized but does not guarantee *FLOW of O2.
 What are some methods we use to prevent hypoxic gas mixture delivery to our pts?

correct gas filling in the tank(not our job)
pin index or diameter index system (connection safety)
"failsafe" valve or OFPD
Link25 or ORMC
FIO2 delivery gas analysis.
Sao2/ABG
Always on 200cc O2 flow.
O2 as last gas on flowmeter assembly.