Surgical Drains Flashcards
What actions do penrose drains rely on? (4)
- Capillary action
- Gravity
- Overflow
- Fluctuations in pressure of space
What wound is a penrose drain best suited for?
Smaller, superficial wounds with low to moderate exudate.
Where does the drainage occur with a penrose drain?
Along outside of tube
What ratio does a penrose drain provide?
High SA:Vol
Penrose drain:
A) Where does it exit?
B) Exit wound size?
C) Where does the proximal end of the drain lie?
D) How much of the drain should exit?
A) Dependent part of wound
B) exit hole slightly wider than circumference of drain
C) Deep tissues
D) 2-3 cm
How is a penrose drain secured?
To exit point with simple interrupted monofilament nylon
Why should a penrose drain not exit at both ends?
It precludes having the drain in the deep tissues and creates an entry point for bacteria
What is the exception to the rule that penrose drains shouldn’t exit both ends of wounds?
- inguinal
- axillary
(1 exit = acts as a 1 way valve)
Vaccuum drain:
= Where does the tube exit?
= is it dependent?
The tube exits the skin adjacent to the wound and does not have to be dependent.
Vacuum drain:
- Where is the fenestrated portion placed?
in the wound. It should be placed in the deepest part of the wound and can extend along the length of the wound.
How is a vacuum drain secured?
The tube is secured to the skin with a purse-string suture and Chinese fingertrap suture.
How is a vacuum created after placing the drain?
A compressible silicone grenade is attached to the tube. The grenade is squeezed to evacuate air then the vent hole is closed to establish a vacuum.
Penrose or vacuum:
This drain mechanism results in a higher risk of contamination
Penrose
Penrose or vacuum:
This drain mechanism results in a lower risk of excoriation
Vacuum
Penrose or vacuum:
This drain mechanism allows the volume of fluid produced to be quantified
Vacuum
Penrose or vacuum:
This drain mechanism results in negative pressure being created
Vacuum
What law describes laminar flow through a drain? What does this mean practically?
Poiseuille’s law
This means that doubling the diameter of the drain increases flow 16 times, and halving the length doubles the flow.
When should compressible grenades be emptied?
- every 6 hours
- When they fil to 20-30%