Workshop 5 - human factors

Question 1

why do we study human factors?

Answer 1

the patient - patient safety and compliance

to determent the risk of injury - safety

age/ mobility

environment eg workplace/ caregivers vs self administration

literacy assuming aged 16 - education on the device

culture or beliefs

Question 2

what are parenteral routes of administration ?

Answer 2

I.V.
S.C.
I.M.
Transdermal/Intradermal
Rectal
Vaginal
Nasal
Intrathecal
Intra-articular
Occular
Ears (Otic)
Intraperitoneal

Question 3

what is the difference between sc and iv routes?

Answer 3

iv
Immediate onset of action - rapid dosing, Specialist training required and Exacerbation/acute/Loading dose. it more painful than sc

sc
Delayed onset of action Prolonged release (reduced frequency of administration/ reduce peak-trough effects), Self-administration at home, allows Management of chronic conditions and
Less painful than i.v.

Question 4

what are maximum injection volumes?

Answer 4

S.C.- Approx. 1-1.5 mL
I.V.- Bolus: 1-5 mL/kg
I.M.- 2-5 mL
Deltoid- 1mL
Gluteal- 2-3 mL

Groups to consider: Elderly, Obese, pre-existing neurological and neuromuscular conditions, paediatrics

Question 5

what re the difference between ampoules, intravenous infusion and subcutaneous pens?

Answer 5

ampoules:
Single use, no preservatives
Specialist use only- clinical setting (i.e. nurse)
>1 ampoule, or fractions may be needed
Vehicle compatibility important
Patient would not be supplied
Counselling on side effects

iv infusion
Specialist, hospital use
Compounding required
Counselling on side effects

sc pens
Suitable for home administration (Parent, caregiver)
Lower risk compared to i.v.
Different PK
Patient counselling on appropriate device use and side effects

Question 6

what are pharmacist counselling points with pens?

Answer 6

Information on the device
Dosage frequency
Storage requirements
Frequent expected AEs
Removal from fridge prior to injection
Visual inspection to rule out precipitate
Device usage (pinching skin, priming, injection site rotation, device use)

Question 7

what human factors should be considered in device selection?

Answer 7

Patient dexterity- Ergonomics
Eyesight- Visual check
Understanding/Literacy- Injection technique, device manipulation, priming for injection

Question 8

what are the advantages and disadvantages of autoinejctors

Answer 8

Advantages of autoinjectors are they are designed to deliver a fixed dose beforehand, reducing the errors of under or overdosing; have safety features to prevent needle accidents; and can improve patient compliance as it reduces patient efforts to administer the dose

Disadvantages are they can be quite bulky so can be difficult to carry around; the speed is mechanically controlled, therefore may be difficult for the patient to control the pain; and it requires the patient to ensure the medication if mixed properly otherwise there is a risk of administering an inadequate dose

Question 9

what are advantages and disadvantages of pre filled syringes ?

Answer 9

Advantages of prefilled syringes is that the dose is accurately measure which provides the patient with precise measured dose required for therapeutic effect and reduces dosing errors; they are small and compact therefore are easy for frequent travellers to carry; and as the medication dose is already made up, it reduces the risk of contamination as the medication is already in the vial.

Disadvantages of prefilled pens are they can be more expensive due to their manufacturing process; are subject to mechanical failure and may not deliver the correct dose; and training for administration can be quite difficult for patient with neurological problems, therefore may require a health professional for administration