Day 5 Flashcards
Where are Intra-cranial lines place
Right lateral ventricle line placed for Intra Ventricular pressure of the brain
What must invasive lines be placed in to transduce
Liquid
ICP monitoring, what are the waves?
Intra-Cranial pressure, level to tragus (with patient 30-45 degrees), B waves made from arterial pulse 1-4mmhg, C waves made from respiratory cycle 2-10mmhg.
P1 Percussion wave, P2 tidal wave, P3 Dicrotic wave, will not be able to see on our monitors
An abnormal ICP waveform indicates poor compliance but we can not use this one data point to make a diagnosis.
Important ICP values
ICP
Normal ICP < 15 mmhg
Pathological ICP > 20mmhg
Contents by volume:
Parenchyma 80%
CSF 10%
Blood 10%
Zeroing sentence
(OFF TO THE PATIENT, OPEN TO AIR, ZEROING LINE, CONFIRM LINE HAS BEEN ZEROED)
causes for overdamping
Causes for overdamping: Frequently most common
1. Loose connections or not enough pressure in the pressure bag, or bad is empty
2. Air bubble in the line
3. Kink in line, Overcompliance of tubing
4. Blood clot in catheter
5. Arterial spasm (distal to catheter the body squeezes shut to protect the artery and block blood flow., This will resolve)
causes for underdamping
Causes for underdamping:
1. Catheter whip (artifact)
2. Tight line (if cold or frozen)
3. Hypothermia, Tachycardia
(or patient dying)
Square waveform test
Normal damping is 1.5-2 oscillations on normal patient, overdamped doesn’t bounce, underdamped bounces a lot (wobbly line more than 2 oscillations)
Why do we use distal port for pressure checks
Have to use the Distal port to check waveform as it’s the most direct port to the area being measured
Does CVP equal volume status?
CVP does not equal volume status by itself
What lines do we measure
CVP
ART Line
EVD
Reasons to perform drug therapy
Prevent, Cure, and Control
Pharmacokinetics
what the body does to the drug) Absorption, distribution and redistribution, metabolism, excretion
Pharmacodynamics
Effects, Side-effects, Mechanism of action
Every drug will cross one or more cell membranes, list them
Every drug will have to cross one or more cell membranes
Passive (Concentration Gradient), Small, Lipid-soluble, Non-polar drugs
Facilitated (Channels/Carrier Proteins), Large, Water-soluble, Polar drugs
Active Transport (Against Concentration Gradient)
Bulky Transport (Endocytosis), Very large drug molecules, the cell itself surrounds and takes in the molecule
Bioavailability
How much is available to be used, the fraction of an unchanged drug that reaches circulation in the unchanged form (F)
The drug may not just be metabolized or excreted and that’s why it’s not having an effect, it may no longer be having an effect as it’s been redistributed to another area of the body
What is distribution and what is it dependant on
Distribution: Movement of a drug from the circulation into body tissue
Dependent on:
Tissue blood supply (More rapidly to Brain, Liver &Kidneys, less rapid to the skin, and adipose tissue)
Size and Polarity of the drug (smaller hydrophobic or lipid soluble drugs more easily cross cell membranes, Larger hydrophilic drugs tend to remain in the plasma)
Plasma protein binding (Partly bound to plasma proteins [reservoir] party unbound [free to diffuse into tissue]
Whats a selective barrier? one example
Selective Barriers
Strictly regulated
Restrict large water-soluble drugs
Allows smaller, lipid-soluble drugs to cross
Protects the brain from toxins and pathogens
Regulate brain environment
Whats phase 1 metabolism
Phase 1 Metabolism
-Oxidation (cytochrome P450)
-Reduction
-Hydrolysis
-Converts parent drug to move water-soluble active metabolite by inserting a polar function
Whats phase 2 metabolism
Phase 2 Metabolism
-Glucuronidation, Acetylation, Sulphation
-Converts parent drug to a more water-soluble inactive metabolite but conjugation groups to function, group,
-Renal excreted
-Slow acetylators may have toxic drug levels due to decreased rate of metabolism
First-order Kinetics
The rate of drug metabolism is directly proportional to the concentration of the drug (to a point where it maxes out)
Zero order kinetics
A constant amount of drug metabolism per unit of time (ASA, ethanol, phenytoin) important if patient is drunk cant make a determination until sober
Whats drug clearance?
Volume of plasma in which all drugs appear to be removed in a given time. Can be used to calculate drug half-life, More drug is distribution means a longer time to clearance.
What are the two types of deicing fluid
Type 1 Orange fluid heated fluid melts
Type 4 Green (LIKE MONEY ITS EXPENSIVE LASTS LONGER) Anti icing, adheres to wing that allows aircraft to take off as ice can’t stick (roughly 45min in YVR)
