IV Cannulation

What are common veins for IV cannulation?

Digital veins, metacarpal veins, cephalic vein, basilic vein, and median vein.

What are the signs of a suitable vein for cannulation?

Bouncy, soft, large enough to accept the cannula, straight path, and no pulse.

What is the risk associated with IV cannulation?

Bacteraemia which can lead to sepsis.

What does ANTT stand for?

Aseptic Non-Touch Technique.

What are contraindications for IV cannulation?

Local trauma, phlebitis, infection, sclerosed vein, AVF, IV infiltration, and haematoma formation.

What is CI-AKI?

Contrast-Induced Acute Kidney Injury.

What types of medications are used to treat anxiety?

Antianxiety medications such as Diazepam.

Epidermis

Outer layer and least sensitive containing dead squamous cells.

The dermis

Thicker layer more sensitive with blood vessels.

Vein - tunica externa

Outermost layer, a strong outer layer with collagen and elastic fibres allowing vessels to stretch.

Vein - tunica media

Middle layer. Smooth muscle which contains nerve fibres that allow veins to contract or relax in response to temperature.

Veins- tunica intima

Inner layer. Contains valves to ensure blood flows in one direction.

Cannula

Should be placed in direction of blood flow. Valves can be found at branches of the vein and prevent advancing cannula into the lumen

Don’t canulate when

Hard veins, bumpy, flat, inflamed, small of fragile

Flashback chamber

To know you are in a vein you should get flashback in the flashback chamber. When flushing there shouldn’t be discomfort.

Bacteraemia

Can turn into sepsis and can be life threatening. Bacteria in the blood

Indications for IV cannula

• introduction of contrast

• Drugs/fluids

• Ambling

• Transfusion

Contraindications for IV cannula

• local trauma

• Phlebitis - inflammation of vein, results in swelling

• Infection

• Sclerosed vein - spider vein

• Artiovenous fistula

• IV infiltration

• Haematoma formation - similar to extravasation

Cannula sizes

14g - orange for trauma patients

16g - grey ideal for rapid fluid infusions

18g - green standard adult

20g - pink standard ideal for ct

22g - blue small adult

24g - yellow paediatrics

Osmosis

The movement of water across a semi-permeable membrane

Osmotic activity

Process where water diffuses across a cell brand in response to solution

Osmolality

The number of milliosmoles per kilogram of water, concentration of molecules per weight of water

Osmolarity

The number of miliosmoles per litre of solution

Triodinated benzoic acid

The most frequently used contrast will be a derivative of this

GI tract

Barium sulphate is used. Prefered contrast media, provides more visualisation without local effects.

Barium sulphate

Cannot be used intravenously. Contra dictied if patient is suspected to have a perforation because not absorbed through serous a of abdomen

Gadolinium 64 - paramagnetic

Compounds rapidly distribute into intracellular and extravascular spaces. Good at CNS lesions

Gadopentete salts - paramagnetic

Are used in renal, hepatic,myocardial and musocoskeletal imaging

Iron 26 - paramagnetic

These compounds contain iron particles that are highly paramagnetic, stay in blood stream, for long. Used to demonstrate hepatic and lymphoid tissue lesions.

Manganese 25 - paramagnetic

High paramagnetic and have high affinity for hepatic cells. It is primarily used for identifying cancers that have hepaocytes in their matrix.

Ultrasound microbubble agent.

These contrast agents have acoustic properties to enhance the ultrasound image. Octafluoroproane is prepared in a microsphere which is essentially an emulsion gas.

Asthma

Increased risk of severe contrast reactions. Contraindications.

Renal disease

If a patient has renal impairment then all contrast agents ate nephrotoxic

CI-AKI - contrast induced acute kidney injury

Anything relating to nephrotoxicty caused by contrast agents is termed as

Risk factors for CI-AKI

• chronic kidney disease (low egfr)

• Heart failure

• Renal transplant

• 75 YO+

• Hypovolaemia - loss of salt and water

Metformin

• blood thinner used for diabetics with renal impairment. Only stop metformin for 48 hours if egfr is beyond limit

Hyperthyroidism

Is patient has hyperthyroidism no contrast. If patient has underachieve thyroid give contrast.

Contrast reactions - skin

Skin reactions up to a week after the administration of contrast. Common with iodine-based contrast.

Contrast reactions -

Nausea/vomitting

Urticaria - hives

Contrast reactions - bronchospasm

Difficultly to breathe because of sudden spasm/constriction of bronchioles.

To combat. Oxygen mask, adrenaline elevate patients legs administration 0.1-0.3mg intramuscularly.

Contrast reactions - laryngeal oedema

Where fluid builds up abnormally in the tissues of the larynx, causing swelling.

To combat use oxygen mask, repeat as needed

Contrast reaction - hypotension

Low blood pressure.

To combat: oxygen mask, intravenous fluid rapidly, saline or lactated ringers solution.

Contrast reaction - anaphylactic reaction

Allergic reaction:

• call resus team

• Suction airway if needed

• Elevate patient legs if hypertensive

• Oxygen by mask

• Adrenaline 0.5mg

• Cardiac arrest when patient can’t breathe

Dose contrast - adult

O.5mg / 500micrograms 1:1000 solution

Contrast dose - paeds over 12

0.5mg 1:1000 solution

Contrast dose - paeds 6-12

0.3mg 1:1000 solution

Contrast dose - paeds under 6

6months - 6 years - 0.15mg

Under 6 months. - 0.01mg

Biopharmaceutics

Large molecule drugs

• suspensions

• Powders

• Capsules

• Tablets

• Enteric coated tablets

Pharmacokinetics

Process of when a drug is administered to when it is excreted/ eliminated from the body

Parameters- absorption

Starts gwen its administered and ingested by the patient via IV or orally

Parameters - distribution

Transportation throughout the blood stream

Parameters - metabolism (biotransformation)

Liver metabolises most drugs, process of chemical changing and drug to metabolite to excrete from the body

Parameters - excretion

Removal of an active drug or metabolite. They filter the blood and remove unbound water soluable compounds.

step 1 of excretion through kidneys - glomerular filtration

Once water and solutes in plasma pass from blood across the glomerular capillaries into glomerular capsule, this fluid empties into renal tubule

Step 2 excretion through kidneys - tubular secretion

The fluid in the tubule will receive secretions (waste) from the tubule and duct cells. These materials include, drugs, wast producrs

Step 3 of excretion through kidneys - tubular resorption

Filtered fluid in the tubule contains water and useful solutes that are reabsorbed (production of urine)

Pharmacodynamics

Involves the effect drugs have on the body at a molecular, biochemical, physiological level after it’s absorbed and distributed to its target.