Anesthesia Medication Safety

Pharmacology and Principles of Anesthetics

• CRNAs are required to minimize infection risk for patients per AANA Standard IX.
• The "One & Only" campaign (one needle, one syringe, only one time) was developed by the CDC and endorsed by the AANA & APSF.

Factors Contributing to Medication Errors in the OR

• Production pressures and emergency/trauma cases increase the risk of errors.
• Multiple medications administered perioperatively and high-risk medications contribute to errors.
• A fast-paced, distracting, complex perioperative environment heightens error potential.
• High-risk patient populations and patients' inability to respond due to sedation/anesthesia add to risk.
• The sole responsibility of anesthesia providers in medication processes is a factor.

Strategies for OR Medication Safety

• Computerized prescriber order entry and barcode technology reduce errors.
• Avoidance of similar-sounding or looking drugs and dedicated OR pharmacists improve safety.
• Adherence to correct labeling of syringes/infusions and proper sterile techniques helps.
• Minimizing verbal orders with read-back techniques and heightened awareness of risks are crucial.
• Medication standardization and American Society of Anesthesiologists color-coded labels promote safety.
• Reinforcing the One & Only campaign is key.

Pharmacokinetics

• Describes what the drug does to the body.
• Receptor activation occurs when drugs bind to specific receptors.
• There are structure-activity relationships.
• Receptor activation is similar to a lock-key mechanism.
• Receptor responsiveness is the body's variable intrinsic sensitivity to a drug.
• Physiological changes like aging impact receptor responsiveness over time.
• Pharmacokinetics describe what the body does to the drug.

Pharmacokinetics

• Defines what the body does to a drug.
• Absorption, or bioavailability, measures the unchanged drug portion reaching systemic circulation.
• Influential absorption factors include administration route (oral, IM, sub-Q, IV), drug formulations, and physiological conditions like gastric pH or motility.
• Small intestine is the main absorption site due to its large surface area.
• Distribution determines how much drug reaches the action site location.
• A drug's capacity to cross membranes depends on its properties like lipophilicity, and molecule size.
• Factors affecting distribution include tissue blood flow and protein binding, like albumin.
• Primary metabolism site occurs in the liver via CYP450 enzymes.
• Some drugs can convert to active metabolites, which may enhance or prolong drug effects, it depends on genetics.
• Excretion primarily occurs via kidneys, also liver via bile, and lungs via exhalation.
• Impaired renal or hepatic function can lead to drug accumulation and toxicity.

Routes of Administration: Oral

• Common, convenient, and inexpensive with increased patient compliance
• Uncommon for anesthesia pre & intraoperatively and causes drug destruction by digestive enzymes and unpredictable absorption.
• The drug can be destroyed by digestive enzymes,. GI conditions affect rate/extent of absorption.

Routes of Administration: Sublingual/Buccal

• Rapid entry to circulation and onset, with no first pass effect, and rapid delivery to the superior vena cava.
• Excessive salivation affects absorption.

Routes of Administration: Nasal

• Similar to sublingual, it avoids first pass metabolism and is convenient for emergencies.
• Absorption relies on nasal mucosa integrity, and administration may be unpleasant/irritating.

Routes of Administration: Rectal

• Systemic absorption quickly.
• Includes first pass hepatic effect with variable drug effect which depends on location
• Proximal administration causes absorption via the superior hemorrhoidal vein through the portal system and may undergo first pass in the liver leading to an unpredictable response, whereas, distal avoids systemic elimination.
• Rectal indomethacin assists in decreasing the increase of post-ERCP pancreatitis.

Routes of Administration: Topical/Transdermal

• Sustains plasma levels from one dose.
• Can be limited to systemic circulation, with possible dermatitis.
• Stratum corneum regeneration occurs every 7 days, impacting update of absorption.

Routes of Administration: Subcutaneous

• Faster absorption vs. transdermal/topical.
• Can cause local tissue necrosis.

Routes of Administration: Intramuscular

• Faster absorption than subcutaneous
• Risk of local tissue necrosis, pain especially with reduced subcutaneous perfusion.

Routes of Administration: Intraosseous

• IO access pursued when traditional access is hard.
• All meds and blood injected through this route
• Risk of infection and with limited sites.

Routes of Administration: Intralingual

• Rapid absorption on with a rapid response.
• Specific training required for approach.

Routes of Administration: I.V

• Fastest rate without absorption and systemic circulation.
• Used most by providers
• Specific training for administration

Routes of Administration: Intra-arterial

• Useful diagnostically or therapeutically with systemic effects.
• Can cause lower vascular irritation not used in anesthesia
• Vasodilators shown to impede artery spasm, while heparin avoids thrombus creation.

Routes of Administration: Inhalation

• Administration without IV access
• Useful for gases, volatile agents and aerosolized substances.
• Drugs quickly reach the blood stream and the lungs allow for uptake
• Affected by lung diseases.

Bioavailability

• It relates to the systemic absorption level and is the extent to the drug meets its effect site destination.

Extent to which a drug reaches its effect site

• Intravenous is 100% Topical is 0-100%
• Sublingual is 60 to 100%
• Oral is 5 to 100%
• Intrathecal is low
• Rectal is 30 to 100%
• Intramuscular is 75 to 100%
• Intraosseous is upto 100% depending on the site.
• Inhalation is 5 to 100%
• All are limited due to the capacity.

Absorption

• This stage supports drugs that will target bodily organs
• Drug must use biological transportation
• Types include:
• Simple diffusion: utilizes high concentrated movement without any assistance
• Active transport: Requires energy
• Pinocytosis: engulf liquid from the enviornment
• Facilitated diffusion: lipid substances will diffuse in the cell with glucose and carbines.

Factors affecting absorption:

• Degree of ionization is determined by Pka
• Drugs appear in both ionized and nonionized solutions
• Water soluble: screw in and they go through metabolism
• Fat Solubles: no hepatic metabolism
• Acid/Bases are ionized in PH

Acidic Drug in a solution

• Acid will donate H with basic solutions
• Acid will do what it does always
• Acid drugs such as barbs at a high pH with opioids and local anesthetic with acidity
• Acidic is for water and Basic is for water except the pH

Trapping

• The drug is Lipid and can produce some activity with mono addition
• Anesthetic, weak, bases nonionised can travel through placenta
• Fetus has a lower pH
• There are medications that come into play with the medications that can reduce effects and others

Henderson Hasselbach Equation

• pH = pKa + log [A-]/[HA]
• A- (Conjugate Base)
• HA (Weak Acid)
• pH = pKa + log [A-]/[HA]
• Ka = !.X 10-5 For acetic acid
• PKA +Log(5)/(5) or negative number.

Distribution

• Initial: medication dispersed with injection with bodily dilution.
• Attraction: molecules link with other sites.
• Polar mixes with water

Perfussion

• Nonpolar mixes with fat
• Injection goes directly to any blood flow, liver, kidneys, brain: rich in vessels.
• Fat does its job in the limited blood

Anesthetic Properties

• Many contain poor water mixture content
• Vessel rich receives 75% of cardiac output verse the 10%
• 25% for muscle, poor, fat (2x mass)
• Solubility: alters drug with bodily mixing
• More to pour= leading for tissue

Volume Mixing:

• Definition
• Represents with post intravenous administration of distrubution of drugs
• Aids in the process of dose loading with a stable state
• Helps understand compartments: plasma, inter fluid, cell, and the whole body

Theoretical Compartments and Volumes

• Total cell water is 40
• Plasma is at 4L, if 23 % in the chart
• Inter is L and extra is combining all
• Cell has 28 L
• Whole contains the other 3 combined (14(E)
• Normal with 70 kg
• Can divide 42 over the 70kg - 0.6L

Large Volume( >0/6L)

• If exceeds, drugs contain TBW
• The body water contains fats
• It has better does at concentration

Small Volume

• If les then TBW
• Volume stays below
• Needs a lower dose

Impact

• How volume changes: Higher concentration of the medication, decrease the body water, and its a small value
• Intially, fat slow for supply However then the timer will be less for drug to mix and will end up in the tissue Patients feel effects during elimination V of D during steady varies from the injection: in time LOWER HIGH MIXING

Modals

• Define bodily distinct sections into the tissue
• Used to forecast the changes in other fluids

Single:

• Has one compartment

• Does not differentiate among all throughout body

• 2x: vessels

• Contain the lungs, the major organs.

  • The C contains 10 percent of the body but gets 75 percent.

Model Groups

• Peripheral: Vessels
• Contains muscle bone
• Body gets is in the phase
• Phase: Drug enters leave
• The main volume is the small volume.

Protien Binding

• Intro by meds with the proteins
• Cant across cell membrane Hydrophill and Solube mix more P- acid mix with albumin

Power

• Albunmin: mix drugs, binds to increase concentrate
• An increase of concentration for the DRUG Conditions
• What reduced for albumin Aging. disease can hurt all that, but it gets less when the protein bound with albumin 2.8 bound will be freed
• Zero

KINETICS

• Constant and A mounts Levels need complete System Rate proportion to The greatest when higher.

Metabolism

• Turn fluids into water Changes due to side effect -Activate – Enzyme – The site metabolizes. Important to have –Liver

Hepatic Microsomes Enzymes

• Enzyme: absorb the site Enzyme: Mixed functions

IsoEnzymes

• Cypt C and it can effects.

phase:

• Water fluids to give the best Enzymes: – Non cypt and oxygen

Reaction catalyzed – Mole comes into it and oxidizes it to eliminate it as a factor

Reduction

• Electrons for the molecules when low The process involves additions for compounds, makes them easier to use

Hydro: – Added to a compound spilt APART The addition makes a get alcohol Will add and get it.

Zone 2

• Makes it work with kidneys Syntech: has little or no reaction DRUG : has I-II Or S II

Phase2 E: –Transfer to the liver with the right Acetyl: has great water. -Cypt or enzymes

Inhibitors

• Stimulus with the E Increased dose with the R

Hepatic Time Pass -Affects with Oral

Process

• Organs are at good level
• The body: is from organs and body fluids Important: to organs and metabolism is what are the organs functions Important: to organs or what did they do?
• Life depends on conctation

Kinetics

• Rate on half life and concratation and the times D: 4to5 - 2 of clearness On the first to make sure of levels

The time is has a small value is Amount depends what model will follow. Parameter: –H time level has concentration: it is not a long term.

Clearance

• Oargns are for liver and kidneys -Rate is the blood level of the organs
• Volume of the volume during the type

The 2 things is to keep a a good steady rate Water helps with hydro –Does –Hepatic

Cleans

– Perfision

• Increases : –high to great –depends on the function

• Related to the suppression

• Related to the flow of the main processes

–Renal is filtration to keep some drugs

• The aids when the tubes flow -Amount helps helps

Other Affect

• Age increases when its poor. It gets better.
• The is 25-30 percent it has a rate is still with alcohol.
• Metabolism decreases with blood –Decrease increase -Has high high. -The have a little effect

Imparas With

• High fluids , with kidney this means high effect to fix it or treat with the drugs .
• This means it also reduces fluid intake

The Goal

The process and is also with its action structure of : are used to explore the drug interaction

Receptors:

• Definition of protein binding which chemicals are in the system

They also show what drugs are not working or what chemicals are binding together or how does this drug does

• Drug receptor and their bond is what is the duration.

receptor

• A- Strong - Weak: is with hydrophobic ion -B- Ago: has the has to be or an action.

• C An -A: only with activity blocked.

partial

• D: Is Non: it blocks or can't get in