New Approach for Managing Blood Waste
- Captures blood waste and saline wash into a sealed bag
- Waste does not enter fraction collector
- No cleanup of fraction collector cold well
- Everything is now disposable from animal to waste
- Suitable for studies with radioisotopes
- Reduces operator’s exposure to blood
- Better approach for studies using infectious agents
Disposing of Waste Blood
The BASi Culex ® Automated Blood Sampler uses sterile catheters connected to sterile disposable tubing on the instrument to (a) withdraw blood from the animal, (b) divert an aliquot to the collection vials, (c) and return any blood remaining in the catheter to the animal with a following flush of sterile saline to replace the fluids withdrawn. Using the standard BASi Culex ® software* there is 50µL of blood remaining in the fraction collector tubing at the end of each sampling sequence. This is considered “waste” and is not returned to the animal. Instead, it is flushed with saline into a waste line which starts inside the fraction collector and terminates at a waste collection bottle underneath the cart.
This approach to waste management requires that the user routinely clean out the fraction collector line after each experiment. The procedure involves removal of the sample carousel, a squeeze bottle with a long nozzle, and a cotton swab. The cleaning solution is 10% bleach (10 mL Chlorox bleach** in 90 mL water). The goal is to flush any blood residue down the collection line and prevent the growth of microbes in the waste line.
Problems Associated with Cleaning The Waste Line
In our experience, this cleanout procedure is sometimes overlooked, which can create a problem with blockage due to vigorous microbial growth in the waste line. In other cases, the cleanup is actually too vigorous and some users have sprayed or spilled cleaning solution into other parts of the fraction collector, compromising the function of temperature sensors and electronics. In some cases, users have used other cleaning solutions containing organic solvents (e.g. alchohols) which have dissolved the adhesives used to support the waste line and created leakage inside the fraction collector.
Using Radioisotopes or Infected Animal Models
Some users have developed specific needs which are not well served by the aforementioned cleaning method. The present cleaning method could expose the user to blood from the animal and this is not desirable when:
- Dosing with drugs labeled with radioactive isotopes
- Using animal models in which the blood contains viable microorganisms (virus, bacteria or parasites)
A New Approach
We have developed another approach to deal with blood waste. This is currently considered “experimental”. We are seeking feedback from BASi Culex ® users to determine how successfully this approach can be transferred to other laboratories. If the feedback is positive, we will incorporate this new approach by modifying the contents of the standard BASi Culex ® tubing set. This new approach accomplishes the following goals:
- Diverts all blood waste to a bag mounted outside the fraction collector.
- No blood or saline from the BASi Culex ® is dispensed into the cold well
- Waste fluids are now contained in a completely disposable system.
- Both the inside and outside of the fraction collector needle are washed between samples to further reduce possible cross-contamination between samples
- The only fluid running down the old waste line inside of the fraction collector is clean water produced by condensation of water vapor in the room air.
- Still permits collection of blood samples into sealed vials
- Still permits use of “no-waste” blood methods
Potential Problems
This new approach also requires caution by users. The BASi Culex ® tubing set was intended to be used for one animal, and is warranted for that purpose. We have found some laboratories reusing the same tubing sets for several animals. Repeated use of the new blood waste technique beyond an estimated maximum of 30 samples will probably lead to failure of the waste collection technique. Thirty samples should be more than enough to accommodate the use of one rodent, even with duplicate sets of blood samples as in a bioavailability study. Users who continue to re-use the same tubing set will encounter serious problems with leakage of waste material into the fraction collector.
CX-5030 BASi Culex ® Waste Containment Kit
Each waste containment kit includes the following 4 components:
- Glass waste vial with plastic hat
- Waste line with luer needle
- Fraction Collector Needle with Two Cannulae
- Bag hook
The 4th component required for this kit is a waste bag. The best choice is to recycle an old saline bag from a previous BASi Culex ® experiment. Please do not use glass serum bottles!
Instructions for Use
- Set aside the fraction collector needle provided with the BASi Culex ® tubing set
- Insert the new dual-cannula needle into the fraction collector
- Attach the BASi Culex ® tubing set to the vertical cannula (smallest diameter cannula)
- Locate the yellow sleeve on the end of the waste tubing
- Attach the yellow sleeve to the angled cannula (largest diameter cannula) on the needle
- The angled cannula on the needle should slip inside the yellow sleeve and also slip inside the rigid tube on that sleeve. Twist and slide the yellow sleeve until the cannula can enter the rigid tube, and the yellow sleeve covers the entire cannula, as shown.
- Remove the cover from the purple luer needle and use it to poke a hole between the two ports on the saline bag for the bag hook.
- Insert the purple luer needle through the septum of the waste bag.
- Use the waste hook to suspend the bag on the BASi Culex ® cart partition. Please note the position of the bag relative to the fraction collector. Do not place it higher, or lower than shown.
- Set aside the standard waste vial (plastic vial with hole in the bottom) from the BASi Culex ® tubing set
- Place the glass waste vial with the plastic hat into the W position on the fraction collector carousel.
- Place the needle DOWN into the waste vial.
- The waste vial and the whole length of waste tubing up to the waste bag should be filled with heparinized saline (about 1200 µL) prior to introducing blood into the vial (just to be safe). Also filling the waste line with saline will assure that pressure is equalized so there is no chance of affecting the accuracy of the blood collection in the first vial.
- You may now connect the animal to the BASi Culex ® tubing set as usual.
- After you withdraw sufficient blood to capture the air bubble in the line and test catheter patency, return the blood to the animal first (using ~ 300µL of saline to flush the catheter) and then flush blood from the waste line (using ~ 500µL of saline).
- Place the BASi Culex ® on TEND
- After each programmed blood sample, the waste blood will be flushed into the vial and then out of the vial through the waste line and into the bag. Between samples, air bubbles will appear every time the needle is withdrawn from the waste vial and moved to the sample vial. These bubbles only appear in the waste line connected to the waste bag and help to move the blood waste and saline and clean that line.
* New software employing the “no-waste” method -- which leaves no blood in this line ---- was developed for mice and is now being developed for rats (Win/98 and Win X/P version) for a January, 2004. New users (and old users getting software upgrades) will notice a prototype version on their BASi Culex ® software disk
** Bleach is the common name for sodium hypochlorite -- NaOCl
