Lec 2- Aseptic

Question 1

What contamination

Answer 1

• Prevent infection (micro-organism)
• Prevent Phlebitis (particulate effects)
• Avoid an ADR

Question 2

anInflammation of a vein- Phlebitis

Answer 2

• Several factors may initiate the process by increasing pressure on and within a vein
• Increase intra-abdominal pressure can lead to partial obstruction of blood flow through the pressure into the legs and if prolonged it can stretch and damage the walls of the veins with resulting inflammation and thrombosis
• Periods of inactivity such as in long haul air travel or being confined to bed can also cause intravenous thrombosis from back pressure and stasis. Changes in levels of oxygen in the blood during prolonged flights can add to the effects of stasis
• Varicose veins are caused by the absence of or damage to the valves within a vein which allows significant back pressure and stasis of blood within the legs. Back pressure transmits to the smaller superficial veins and can result in superficial thrombophlebitis in the lower leg
• Obstruction in the chest or neck from malignancy or other diseases can impede the flow of blood from the upper limbs and result in thrombophlebitis although it is much less common in upper than lower
• Damage to the vein wall from the injection of irritant substances and injection using infected needles can cause thrombophlebitis as can prolonged insertion of cannulae for IV infusion

Question 3

Phlebitis

Answer 3

• Varicose veins are caused by the absence of or damage to the valves within a vein which allows significant back pressure and stasis of blood within the legs. The back pressure transmits to the smaller superficial veins and can result in superficial thrombophlebitis in the lower leg
• Obstruction in the chest or neck from malignancy or other diseases can impede the flow of blood from the upper limbs and result in thrombophlebitis although it is much less common in the upper than the lower limbs
• Damage to the vein wall from the injection of irritant substances, and injection using infected needles can cause thrombophlebitis as can prolonged insertion of cannulae for IV infusion

Question 4

Human contamination

Answer 4

• You are very dirty
  
  • Walking 5,000,000 skin squames
  • Moving 1,000,000 skin squames
  • Sitting 100,000 skin squames
  • Standing 100,000
• Enforce a strict SOP to stop squame entry to the clean room

Question 5

Handwashing

Answer 5

• Face
• Hair
• Full body
• Wounds
• Tattoo, rings, long nails

Question 6

Contamination

Answer 6

• 15% of contamination is from poor filtration- HEPA filters not working as efficiently as they should do
• 25% equipment- bringing in equpiment (vials, injections etc) from other often lower grade areas can result in contamination if not cleaned properly- not steralised/wiped
• 60% from human error

Question 7

Viable Contaminants

1) Bacterial

Answer 7

• Pseudomonas
  
  • Rod shaped bacteria, plate colour “Earthy green” on plate
• Staphylococcus
  
  • Cocci= spherical. Blood rich agar “creamy gold” on plate

Question 8

Viable Contaminants

2) Fungus

Answer 8

• Sporotrichosis
  
  • Fungi must send to histology can’t follow colour of the plate

Question 9

Viable Contaminants

3) Viral

Answer 9

• Herpes simplex virus
• Pay attention to slide colour- Green
• Fluorescing outer cell membranes under microscope indicate HSV presence

Question 10

Viable Contaminants

4) Endotoxin- Exotoxin

Answer 10

• Endotoxin
  
  • Protein complexes released at cell lysis
  • Non-specific toxicity cause pyrexia
  • Heat stable
  • G -Ve
  • E.g. E.coli
• Exotoxin
  
  • Proteins excreted from the cell
  • Specific in action- toxic
  • Heat-labile
  • G +Ve
  • E.g. Vibro cholera

Question 11

Typical TPN bag

Answer 11

• Has 2.5 million particles
• You would prefer they are non-viable

Question 12

Cleaning a clean room

Answer 12

• Clean rooms will become contaminated people working produce particles
• Cleaning- removal of visible items
• Decontamination- Removal of contamination that cannot be seen
• Disinfection- Destruction of micro-organisms
• Steralise-
  
  • Absolute term: Destruction of ALL micro-organisms
  • Must be conform to BP sterility test requirements i

Question 13

Disinfection- Decontamination

Answer 13

• The equipment
  
  • Vacuum
  • Mop
  • Buckets
  • Wipes
• Supplies
  
  • Water (sterile for irrigation)
  • Detergents
  • Disinfectants

Question 14

How often do you clean

Answer 14

• Grade A- every time you work with it
• Grade B- Every time you work the area- before and after
• Grade C- Start and end of the day
• Floors, walls, ceilings need decontaminating and disinfecting weekly (or monthly depending on work lead)
• All of this is required to control contamination and keep it at its lowest

Question 15

Not enough time to clean

Answer 15

• Particle contamination goes up
  
  • In a single bag of TPN (Total Parenteral Nutrition) 2.5 million particles have been found
  • In a bad bag, it could be almost double or worse